Merge pull request #909 from pwpiwi/fix_button_break

[proxmark3-svn] / armsrc / iso14443a.c

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index a4632aa543cff67e05fb3b1d4c74cc56c95ca76a..31a3e4ccc1e2bc48415d22a04501ad927a8b0cdb 100644 (file)
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -10,22 +10,81 @@
 // Routines to support ISO 14443 type A.
 //-----------------------------------------------------------------------------
 
 // Routines to support ISO 14443 type A.
 //-----------------------------------------------------------------------------
 

+#include "iso14443a.h"
+
+#include <stdio.h>
+#include <string.h>

 #include "proxmark3.h"
 #include "apps.h"
 #include "util.h"
 #include "proxmark3.h"
 #include "apps.h"
 #include "util.h"

-#include "string.h"

 #include "cmd.h"
 #include "cmd.h"

-

 #include "iso14443crc.h"
 #include "iso14443crc.h"

-#include "iso14443a.h"
-#include "crapto1.h"
+#include "crapto1/crapto1.h"

 #include "mifareutil.h"
 #include "mifareutil.h"

+#include "mifaresniff.h"
+#include "BigBuf.h"
+#include "protocols.h"
+#include "parity.h"
+#include "fpgaloader.h"
+
+typedef struct {
+       enum {
+               DEMOD_UNSYNCD,
+               // DEMOD_HALF_SYNCD,
+               // DEMOD_MOD_FIRST_HALF,
+               // DEMOD_NOMOD_FIRST_HALF,
+               DEMOD_MANCHESTER_DATA
+       } state;
+       uint16_t twoBits;
+       uint16_t highCnt;
+       uint16_t bitCount;
+       uint16_t collisionPos;
+       uint16_t syncBit;
+       uint8_t  parityBits;
+       uint8_t  parityLen;
+       uint16_t shiftReg;
+       uint16_t samples;
+       uint16_t len;
+       uint32_t startTime, endTime;
+       uint8_t  *output;
+       uint8_t  *parity;
+} tDemod;
+
+typedef enum {
+       MOD_NOMOD = 0,
+       MOD_SECOND_HALF,
+       MOD_FIRST_HALF,
+       MOD_BOTH_HALVES
+       } Modulation_t;
+
+typedef struct {
+       enum {
+               STATE_UNSYNCD,
+               STATE_START_OF_COMMUNICATION,
+               STATE_MILLER_X,
+               STATE_MILLER_Y,
+               STATE_MILLER_Z,
+               // DROP_NONE,
+               // DROP_FIRST_HALF,
+               } state;
+       uint16_t shiftReg;
+       int16_t  bitCount;
+       uint16_t len;
+       uint16_t byteCntMax;
+       uint16_t posCnt;
+       uint16_t syncBit;
+       uint8_t  parityBits;
+       uint8_t  parityLen;
+       uint32_t fourBits;
+       uint32_t startTime, endTime;
+       uint8_t *output;
+       uint8_t *parity;
+} tUart;

 
 static uint32_t iso14a_timeout;
 
 static uint32_t iso14a_timeout;

-uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET;
+#define MAX_ISO14A_TIMEOUT 524288
+

 int rsamples = 0;
 int rsamples = 0;

-int traceLen = 0;
-int tracing = TRUE;

 uint8_t trigger = 0;
 // the block number for the ISO14443-4 PCB
 static uint8_t iso14_pcb_blocknum = 0;
 uint8_t trigger = 0;
 // the block number for the ISO14443-4 PCB
 static uint8_t iso14_pcb_blocknum = 0;


@@ -35,9 +94,9 @@ static uint8_t iso14_pcb_blocknum = 0;
 //
 // minimum time between the start bits of consecutive transfers from reader to tag: 7000 carrier (13.56Mhz) cycles
 #define REQUEST_GUARD_TIME (7000/16 + 1)
 //
 // minimum time between the start bits of consecutive transfers from reader to tag: 7000 carrier (13.56Mhz) cycles
 #define REQUEST_GUARD_TIME (7000/16 + 1)

-// minimum time between last modulation of tag and next start bit from reader to tag: 1172 carrier cycles 
-#define FRAME_DELAY_TIME_PICC_TO_PCD (1172/16 + 1) 
-// bool LastCommandWasRequest = FALSE;
+// minimum time between last modulation of tag and next start bit from reader to tag: 1172 carrier cycles
+#define FRAME_DELAY_TIME_PICC_TO_PCD (1172/16 + 1)
+// bool LastCommandWasRequest = false;

 
 //
 // Total delays including SSC-Transfers between ARM and FPGA. These are in carrier clock cycles (1/13,56MHz)
 
 //
 // Total delays including SSC-Transfers between ARM and FPGA. These are in carrier clock cycles (1/13,56MHz)


@@ -48,8 +107,8 @@ static uint8_t iso14_pcb_blocknum = 0;
 // 8 ticks until bit_to_arm is assigned from curbit
 // 8*16 ticks for the transfer from FPGA to ARM
 // 4*16 ticks until we measure the time
 // 8 ticks until bit_to_arm is assigned from curbit
 // 8*16 ticks for the transfer from FPGA to ARM
 // 4*16 ticks until we measure the time

-// - 8*16 ticks because we measure the time of the previous transfer 
-#define DELAY_AIR2ARM_AS_READER (3 + 16 + 8 + 8*16 + 4*16 - 8*16) 
+// - 8*16 ticks because we measure the time of the previous transfer
+#define DELAY_AIR2ARM_AS_READER (3 + 16 + 8 + 8*16 + 4*16 - 8*16)

 
 // When the PM acts as a reader and is sending, it takes
 // 4*16 ticks until we can write data to the sending hold register
 
 // When the PM acts as a reader and is sending, it takes
 // 4*16 ticks until we can write data to the sending hold register


@@ -66,10 +125,10 @@ static uint8_t iso14_pcb_blocknum = 0;
 // 8 ticks until the SSC samples the first data
 // 7*16 ticks to complete the transfer from FPGA to ARM
 // 8 ticks until the next ssp_clk rising edge
 // 8 ticks until the SSC samples the first data
 // 7*16 ticks to complete the transfer from FPGA to ARM
 // 8 ticks until the next ssp_clk rising edge

-// 4*16 ticks until we measure the time 
-// - 8*16 ticks because we measure the time of the previous transfer 
+// 4*16 ticks until we measure the time
+// - 8*16 ticks because we measure the time of the previous transfer

 #define DELAY_AIR2ARM_AS_TAG (2 + 3 + 8 + 8 + 7*16 + 8 + 4*16 - 8*16)
 #define DELAY_AIR2ARM_AS_TAG (2 + 3 + 8 + 8 + 7*16 + 8 + 4*16 - 8*16)

- 
+

 // The FPGA will report its internal sending delay in
 uint16_t FpgaSendQueueDelay;
 // the 5 first bits are the number of bits buffered in mod_sig_buf
 // The FPGA will report its internal sending delay in
 uint16_t FpgaSendQueueDelay;
 // the 5 first bits are the number of bits buffered in mod_sig_buf


@@ -77,13 +136,13 @@ uint16_t FpgaSendQueueDelay;
 #define DELAY_FPGA_QUEUE (FpgaSendQueueDelay<<1)
 
 // When the PM acts as tag and is sending, it takes
 #define DELAY_FPGA_QUEUE (FpgaSendQueueDelay<<1)
 
 // When the PM acts as tag and is sending, it takes

-// 4*16 ticks until we can write data to the sending hold register
+// 4*16 + 8 ticks until we can write data to the sending hold register

 // 8*16 ticks until the SHR is transferred to the Sending Shift Register
 // 8*16 ticks until the SHR is transferred to the Sending Shift Register

-// 8 ticks until the first transfer starts
-// 8 ticks later the FPGA samples the data
-// + a varying number of ticks in the FPGA Delay Queue (mod_sig_buf)
+// 8 ticks later the FPGA samples the first data
+// + 16 ticks until assigned to mod_sig

 // + 1 tick to assign mod_sig_coil
 // + 1 tick to assign mod_sig_coil

-#define DELAY_ARM2AIR_AS_TAG (4*16 + 8*16 + 8 + 8 + DELAY_FPGA_QUEUE + 1)
+// + a varying number of ticks in the FPGA Delay Queue (mod_sig_buf)
+#define DELAY_ARM2AIR_AS_TAG (4*16 + 8 + 8*16 + 8 + 16 + 1 + DELAY_FPGA_QUEUE)

 
 // When the PM acts as sniffer and is receiving tag data, it takes
 // 3 ticks A/D conversion
 
 // When the PM acts as sniffer and is receiving tag data, it takes
 // 3 ticks A/D conversion


@@ -91,16 +150,16 @@ uint16_t FpgaSendQueueDelay;
 // 8 ticks (on average) until the result is stored in to_arm
 // + the delays in transferring data - which is the same for
 // sniffing reader and tag data and therefore not relevant
 // 8 ticks (on average) until the result is stored in to_arm
 // + the delays in transferring data - which is the same for
 // sniffing reader and tag data and therefore not relevant

-#define DELAY_TAG_AIR2ARM_AS_SNIFFER (3 + 14 + 8) 
- 
+#define DELAY_TAG_AIR2ARM_AS_SNIFFER (3 + 14 + 8)
+

 // When the PM acts as sniffer and is receiving reader data, it takes
 // When the PM acts as sniffer and is receiving reader data, it takes

-// 2 ticks delay in analogue RF receiver (for the falling edge of the 
+// 2 ticks delay in analogue RF receiver (for the falling edge of the

 // start bit, which marks the start of the communication)
 // 3 ticks A/D conversion
 // 8 ticks on average until the data is stored in to_arm.
 // + the delays in transferring data - which is the same for
 // sniffing reader and tag data and therefore not relevant
 // start bit, which marks the start of the communication)
 // 3 ticks A/D conversion
 // 8 ticks on average until the data is stored in to_arm.
 // + the delays in transferring data - which is the same for
 // sniffing reader and tag data and therefore not relevant

-#define DELAY_READER_AIR2ARM_AS_SNIFFER (2 + 3 + 8) 
+#define DELAY_READER_AIR2ARM_AS_SNIFFER (2 + 3 + 8)

 
 //variables used for timing purposes:
 //these are in ssp_clk cycles:
 
 //variables used for timing purposes:
 //these are in ssp_clk cycles:


@@ -118,59 +177,33 @@ static uint32_t LastProxToAirDuration;
 // Sequence X: 00001100 drop after half a period
 // Sequence Y: 00000000 no drop
 // Sequence Z: 11000000 drop at start
 // Sequence X: 00001100 drop after half a period
 // Sequence Y: 00000000 no drop
 // Sequence Z: 11000000 drop at start

-#define        SEC_D 0xf0
-#define        SEC_E 0x0f
-#define        SEC_F 0x00
-#define        SEC_X 0x0c
-#define        SEC_Y 0x00
-#define        SEC_Z 0xc0
-
-const uint8_t OddByteParity[256] = {
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
-};
-
+#define SEC_D 0xf0
+#define SEC_E 0x0f
+#define SEC_F 0x00
+#define SEC_X 0x0c
+#define SEC_Y 0x00
+#define SEC_Z 0xc0

 
 void iso14a_set_trigger(bool enable) {
        trigger = enable;
 }
 
 
 void iso14a_set_trigger(bool enable) {
        trigger = enable;
 }
 

-void iso14a_clear_trace() {
-       memset(trace, 0x44, TRACE_SIZE);
-       traceLen = 0;
-}

 
 

-void iso14a_set_tracing(bool enable) {
-       tracing = enable;
+void iso14a_set_timeout(uint32_t timeout) {
+       // adjust timeout by FPGA delays and 2 additional ssp_frames to detect SOF
+       iso14a_timeout = timeout + (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8) + 2;
+       if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", timeout, timeout / 106);

 }
 
 }
 

-void iso14a_set_timeout(uint32_t timeout) {
-       iso14a_timeout = timeout;
+
+uint32_t iso14a_get_timeout(void) {
+       return iso14a_timeout - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8) - 2;

 }
 
 //-----------------------------------------------------------------------------
 // Generate the parity value for a byte sequence
 //
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------
 // Generate the parity value for a byte sequence
 //
 //-----------------------------------------------------------------------------

-byte_t oddparity (const byte_t bt)
-{
-       return OddByteParity[bt];
-}
-

 void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par)
 {
        uint16_t paritybit_cnt = 0;
 void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par)
 {
        uint16_t paritybit_cnt = 0;


@@ -179,10 +212,10 @@ void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par)
 
        for (uint16_t i = 0; i < iLen; i++) {
                // Generate the parity bits
 
        for (uint16_t i = 0; i < iLen; i++) {
                // Generate the parity bits

-               parityBits |= ((OddByteParity[pbtCmd[i]]) << (7-paritybit_cnt));
+               parityBits |= ((oddparity8(pbtCmd[i])) << (7-paritybit_cnt));

                if (paritybit_cnt == 7) {
                if (paritybit_cnt == 7) {

-                       par[paritybyte_cnt] = parityBits;       // save 8 Bits parity
-                       parityBits = 0;                                         // and advance to next Parity Byte
+                       par[paritybyte_cnt] = parityBits;   // save 8 Bits parity
+                       parityBits = 0;                     // and advance to next Parity Byte

                        paritybyte_cnt++;
                        paritybit_cnt = 0;
                } else {
                        paritybyte_cnt++;
                        paritybit_cnt = 0;
                } else {


@@ -192,7 +225,7 @@ void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par)
 
        // save remaining parity bits
        par[paritybyte_cnt] = parityBits;
 
        // save remaining parity bits
        par[paritybyte_cnt] = parityBits;

-       
+

 }
 
 void AppendCrc14443a(uint8_t* data, int len)
 }
 
 void AppendCrc14443a(uint8_t* data, int len)


@@ -200,233 +233,185 @@ void AppendCrc14443a(uint8_t* data, int len)
        ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
 }
 
        ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
 }
 

-// The function LogTrace() is also used by the iClass implementation in iClass.c
-bool RAMFUNC LogTrace(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_start, uint32_t timestamp_end, uint8_t *parity, bool readerToTag)
+static void AppendCrc14443b(uint8_t* data, int len)

 {
 {

-       if (!tracing) return FALSE;
-       
-       uint16_t num_paritybytes = (iLen-1)/8 + 1;      // number of valid paritybytes in *parity
-       uint16_t duration = timestamp_end - timestamp_start;
-
-       // Return when trace is full
-       if (traceLen + sizeof(iLen) + sizeof(timestamp_start) + sizeof(duration) + num_paritybytes + iLen >= TRACE_SIZE) {
-               tracing = FALSE;        // don't trace any more
-               return FALSE;
-       }
-       
-       // Traceformat:
-       // 32 bits timestamp (little endian)
-       // 16 bits duration (little endian)
-       // 16 bits data length (little endian, Highest Bit used as readerToTag flag)
-       // y Bytes data
-       // x Bytes parity (one byte per 8 bytes data)
-       
-       // timestamp (start)
-       trace[traceLen++] = ((timestamp_start >> 0) & 0xff);
-       trace[traceLen++] = ((timestamp_start >> 8) & 0xff);
-       trace[traceLen++] = ((timestamp_start >> 16) & 0xff);
-       trace[traceLen++] = ((timestamp_start >> 24) & 0xff);
-       
-       // duration
-       trace[traceLen++] = ((duration >> 0) & 0xff);
-       trace[traceLen++] = ((duration >> 8) & 0xff);
-
-       // data length
-       trace[traceLen++] = ((iLen >> 0) & 0xff);
-       trace[traceLen++] = ((iLen >> 8) & 0xff);
-
-       // readerToTag flag
-       if (!readerToTag) {
-               trace[traceLen - 1] |= 0x80;
-       }
-
-       // data bytes
-       if (btBytes != NULL && iLen != 0) {
-               memcpy(trace + traceLen, btBytes, iLen);
-       }
-       traceLen += iLen;
-
-       // parity bytes
-       if (parity != NULL && iLen != 0) {
-               memcpy(trace + traceLen, parity, num_paritybytes);
-       }
-       traceLen += num_paritybytes;
-
-       return TRUE;
+       ComputeCrc14443(CRC_14443_B,data,len,data+len,data+len+1);

 }
 
 }
 

+

 //=============================================================================
 // ISO 14443 Type A - Miller decoder
 //=============================================================================
 // Basics:
 // This decoder is used when the PM3 acts as a tag.
 //=============================================================================
 // ISO 14443 Type A - Miller decoder
 //=============================================================================
 // Basics:
 // This decoder is used when the PM3 acts as a tag.

-// The reader will generate "pauses" by temporarily switching of the field. 
-// At the PM3 antenna we will therefore measure a modulated antenna voltage. 
+// The reader will generate "pauses" by temporarily switching of the field.
+// At the PM3 antenna we will therefore measure a modulated antenna voltage.

 // The FPGA does a comparison with a threshold and would deliver e.g.:
 // ........  1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1  .......
 // The Miller decoder needs to identify the following sequences:
 // The FPGA does a comparison with a threshold and would deliver e.g.:
 // ........  1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1  .......
 // The Miller decoder needs to identify the following sequences:

-// 2 (or 3) ticks pause followed by 6 (or 5) ticks unmodulated:        pause at beginning - Sequence Z ("start of communication" or a "0")
-// 8 ticks without a modulation:                                                                       no pause - Sequence Y (a "0" or "end of communication" or "no information")
-// 4 ticks unmodulated followed by 2 (or 3) ticks pause:                       pause in second half - Sequence X (a "1")
+// 2 (or 3) ticks pause followed by 6 (or 5) ticks unmodulated:     pause at beginning - Sequence Z ("start of communication" or a "0")
+// 8 ticks without a modulation:                                    no pause - Sequence Y (a "0" or "end of communication" or "no information")
+// 4 ticks unmodulated followed by 2 (or 3) ticks pause:            pause in second half - Sequence X (a "1")

 // Note 1: the bitstream may start at any time. We therefore need to sync.
 // Note 2: the interpretation of Sequence Y and Z depends on the preceding sequence.
 //-----------------------------------------------------------------------------
 static tUart Uart;
 
 // Lookup-Table to decide if 4 raw bits are a modulation.
 // Note 1: the bitstream may start at any time. We therefore need to sync.
 // Note 2: the interpretation of Sequence Y and Z depends on the preceding sequence.
 //-----------------------------------------------------------------------------
 static tUart Uart;
 
 // Lookup-Table to decide if 4 raw bits are a modulation.

-// We accept two or three consecutive "0" in any position with the rest "1"
+// We accept the following:
+// 0001  -   a 3 tick wide pause
+// 0011  -   a 2 tick wide pause, or a three tick wide pause shifted left
+// 0111  -   a 2 tick wide pause shifted left
+// 1001  -   a 2 tick wide pause shifted right

 const bool Mod_Miller_LUT[] = {
 const bool Mod_Miller_LUT[] = {

-       TRUE,  TRUE,  FALSE, TRUE,  FALSE, FALSE, FALSE, FALSE,
-       TRUE,  TRUE,  FALSE, FALSE, TRUE,  FALSE, FALSE, FALSE
+       false,  true, false, true,  false, false, false, true,
+       false,  true, false, false, false, false, false, false

 };
 };

-#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x00F0) >> 4])
-#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x000F)])
+#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x000000F0) >> 4])
+#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x0000000F)])

 
 

-void UartReset()
-{
+static void UartReset() {

        Uart.state = STATE_UNSYNCD;
        Uart.bitCount = 0;
        Uart.state = STATE_UNSYNCD;
        Uart.bitCount = 0;

-       Uart.len = 0;                                           // number of decoded data bytes
-       Uart.parityLen = 0;                                     // number of decoded parity bytes
-       Uart.shiftReg = 0;                                      // shiftreg to hold decoded data bits
-       Uart.parityBits = 0;                            // holds 8 parity bits
-       Uart.twoBits = 0x0000;                          // buffer for 2 Bits
-       Uart.highCnt = 0;
-       Uart.startTime = 0;
-       Uart.endTime = 0;
+       Uart.len = 0;                       // number of decoded data bytes
+       Uart.parityLen = 0;                 // number of decoded parity bytes
+       Uart.shiftReg = 0;                  // shiftreg to hold decoded data bits
+       Uart.parityBits = 0;                // holds 8 parity bits

 }
 
 }
 

-void UartInit(uint8_t *data, uint8_t *parity)
-{
+static void UartInit(uint8_t *data, uint8_t *parity) {

        Uart.output = data;
        Uart.parity = parity;
        Uart.output = data;
        Uart.parity = parity;

+       Uart.fourBits = 0x00000000;         // clear the buffer for 4 Bits
+       Uart.startTime = 0;
+       Uart.endTime = 0;

        UartReset();
 }
 
 // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time
        UartReset();
 }
 
 // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time

-static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
-{
-
-       Uart.twoBits = (Uart.twoBits << 8) | bit;
-       
-       if (Uart.state == STATE_UNSYNCD) {                                                                                              // not yet synced
-               if (Uart.highCnt < 7) {                                                                                                 // wait for a stable unmodulated signal
-                       if (Uart.twoBits == 0xffff) {
-                               Uart.highCnt++;
-                       } else {
-                               Uart.highCnt = 0;
-                       }
-               } else {        
-                       Uart.syncBit = 0xFFFF; // not set
-                       // look for 00xx1111 (the start bit)
-                       if              ((Uart.twoBits & 0x6780) == 0x0780) Uart.syncBit = 7; 
-                       else if ((Uart.twoBits & 0x33C0) == 0x03C0) Uart.syncBit = 6;
-                       else if ((Uart.twoBits & 0x19E0) == 0x01E0) Uart.syncBit = 5;
-                       else if ((Uart.twoBits & 0x0CF0) == 0x00F0) Uart.syncBit = 4;
-                       else if ((Uart.twoBits & 0x0678) == 0x0078) Uart.syncBit = 3;
-                       else if ((Uart.twoBits & 0x033C) == 0x003C) Uart.syncBit = 2;
-                       else if ((Uart.twoBits & 0x019E) == 0x001E) Uart.syncBit = 1;
-                       else if ((Uart.twoBits & 0x00CF) == 0x000F) Uart.syncBit = 0;
-                       if (Uart.syncBit != 0xFFFF) {
-                               Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
-                               Uart.startTime -= Uart.syncBit;
-                               Uart.endTime = Uart.startTime;
-                               Uart.state = STATE_START_OF_COMMUNICATION;
-                       }
+static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) {
+
+       Uart.fourBits = (Uart.fourBits << 8) | bit;
+
+       if (Uart.state == STATE_UNSYNCD) {                                          // not yet synced
+
+               Uart.syncBit = 9999;                                                    // not set
+               // The start bit is one ore more Sequence Y followed by a Sequence Z (... 11111111 00x11111). We need to distinguish from
+               // Sequence X followed by Sequence Y followed by Sequence Z (111100x1 11111111 00x11111)
+               // we therefore look for a ...xx11111111111100x11111xxxxxx... pattern
+               // (12 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's)
+               #define ISO14443A_STARTBIT_MASK     0x07FFEF80                          // mask is    00000111 11111111 11101111 10000000
+               #define ISO14443A_STARTBIT_PATTERN  0x07FF8F80                          // pattern is 00000111 11111111 10001111 10000000
+               if      ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 0)) == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 1)) == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 2)) == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 3)) == ISO14443A_STARTBIT_PATTERN >> 3) Uart.syncBit = 4;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 4)) == ISO14443A_STARTBIT_PATTERN >> 4) Uart.syncBit = 3;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 5)) == ISO14443A_STARTBIT_PATTERN >> 5) Uart.syncBit = 2;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 6)) == ISO14443A_STARTBIT_PATTERN >> 6) Uart.syncBit = 1;
+               else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 7)) == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0;
+
+               if (Uart.syncBit != 9999) {                                             // found a sync bit
+                       Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
+                       Uart.startTime -= Uart.syncBit;
+                       Uart.endTime = Uart.startTime;
+                       Uart.state = STATE_START_OF_COMMUNICATION;
+                       LED_B_ON();

                }
 
        } else {
 
                }
 
        } else {
 

-               if (IsMillerModulationNibble1(Uart.twoBits >> Uart.syncBit)) {                  
-                       if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) {          // Modulation in both halves - error
+               if (IsMillerModulationNibble1(Uart.fourBits >> Uart.syncBit)) {
+                       if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {     // Modulation in both halves - error
+                               LED_B_OFF();

                                UartReset();
                                UartReset();

-                               Uart.highCnt = 6;
-                       } else {                                                                                                                        // Modulation in first half = Sequence Z = logic "0"
-                               if (Uart.state == STATE_MILLER_X) {                                                             // error - must not follow after X
+                       } else {                                                            // Modulation in first half = Sequence Z = logic "0"
+                               if (Uart.state == STATE_MILLER_X) {                             // error - must not follow after X
+                                       LED_B_OFF();

                                        UartReset();
                                        UartReset();

-                                       Uart.highCnt = 6;

                                } else {
                                        Uart.bitCount++;
                                } else {
                                        Uart.bitCount++;

-                                       Uart.shiftReg = (Uart.shiftReg >> 1);                                           // add a 0 to the shiftreg
+                                       Uart.shiftReg = (Uart.shiftReg >> 1);                       // add a 0 to the shiftreg

                                        Uart.state = STATE_MILLER_Z;
                                        Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 6;
                                        Uart.state = STATE_MILLER_Z;
                                        Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 6;

-                                       if(Uart.bitCount >= 9) {                                                                        // if we decoded a full byte (including parity)
+                                       if(Uart.bitCount >= 9) {                                    // if we decoded a full byte (including parity)

                                                Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
                                                Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);

-                                               Uart.parityBits <<= 1;                                                                  // make room for the parity bit
-                                               Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);               // store parity bit
+                                               Uart.parityBits <<= 1;                                  // make room for the parity bit
+                                               Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);       // store parity bit

                                                Uart.bitCount = 0;
                                                Uart.shiftReg = 0;
                                                Uart.bitCount = 0;
                                                Uart.shiftReg = 0;

-                                               if((Uart.len&0x0007) == 0) {                                                    // every 8 data bytes
-                                                       Uart.parity[Uart.parityLen++] = Uart.parityBits;        // store 8 parity bits
+                                               if((Uart.len&0x0007) == 0) {                            // every 8 data bytes
+                                                       Uart.parity[Uart.parityLen++] = Uart.parityBits;    // store 8 parity bits

                                                        Uart.parityBits = 0;
                                                }
                                        }
                                }
                        }
                } else {
                                                        Uart.parityBits = 0;
                                                }
                                        }
                                }
                        }
                } else {

-                       if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) {          // Modulation second half = Sequence X = logic "1"
+                       if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {     // Modulation second half = Sequence X = logic "1"

                                Uart.bitCount++;
                                Uart.bitCount++;

-                               Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100;                                   // add a 1 to the shiftreg
+                               Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100;                   // add a 1 to the shiftreg

                                Uart.state = STATE_MILLER_X;
                                Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 2;
                                Uart.state = STATE_MILLER_X;
                                Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 2;

-                               if(Uart.bitCount >= 9) {                                                                                // if we decoded a full byte (including parity)
+                               if(Uart.bitCount >= 9) {                                        // if we decoded a full byte (including parity)

                                        Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
                                        Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);

-                                       Uart.parityBits <<= 1;                                                                          // make room for the new parity bit
-                                       Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);                       // store parity bit
+                                       Uart.parityBits <<= 1;                                      // make room for the new parity bit
+                                       Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);           // store parity bit

                                        Uart.bitCount = 0;
                                        Uart.shiftReg = 0;
                                        Uart.bitCount = 0;
                                        Uart.shiftReg = 0;

-                                       if ((Uart.len&0x0007) == 0) {                                                           // every 8 data bytes
-                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;                // store 8 parity bits
+                                       if ((Uart.len&0x0007) == 0) {                               // every 8 data bytes
+                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;        // store 8 parity bits

                                                Uart.parityBits = 0;
                                        }
                                }
                                                Uart.parityBits = 0;
                                        }
                                }

-                       } else {                                                                                                                        // no modulation in both halves - Sequence Y
-                               if (Uart.state == STATE_MILLER_Z || Uart.state == STATE_MILLER_Y) {     // Y after logic "0" - End of Communication
+                       } else {                                                            // no modulation in both halves - Sequence Y
+                               if (Uart.state == STATE_MILLER_Z || Uart.state == STATE_MILLER_Y) { // Y after logic "0" - End of Communication
+                                       LED_B_OFF();

                                        Uart.state = STATE_UNSYNCD;
                                        Uart.state = STATE_UNSYNCD;

-                                       Uart.bitCount--;                                                                                        // last "0" was part of EOC sequence
-                                       Uart.shiftReg <<= 1;                                                                            // drop it
-                                       if(Uart.bitCount > 0) {                                                                         // if we decoded some bits
-                                               Uart.shiftReg >>= (9 - Uart.bitCount);                                  // right align them
-                                               Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);               // add last byte to the output
-                                               Uart.parityBits <<= 1;                                                                  // add a (void) parity bit
-                                               Uart.parityBits <<= (8 - (Uart.len&0x0007));                    // left align parity bits
-                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;                // and store it
-                                               return TRUE;
-                                       } else if (Uart.len & 0x0007) {                                                         // there are some parity bits to store
-                                               Uart.parityBits <<= (8 - (Uart.len&0x0007));                    // left align remaining parity bits
-                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;                // and store them
+                                       Uart.bitCount--;                                            // last "0" was part of EOC sequence
+                                       Uart.shiftReg <<= 1;                                        // drop it
+                                       if(Uart.bitCount > 0) {                                     // if we decoded some bits
+                                               Uart.shiftReg >>= (9 - Uart.bitCount);                  // right align them
+                                               Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);       // add last byte to the output
+                                               Uart.parityBits <<= 1;                                  // add a (void) parity bit
+                                               Uart.parityBits <<= (8 - (Uart.len&0x0007));            // left align parity bits
+                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;        // and store it
+                                               return true;
+                                       } else if (Uart.len & 0x0007) {                             // there are some parity bits to store
+                                               Uart.parityBits <<= (8 - (Uart.len&0x0007));            // left align remaining parity bits
+                                               Uart.parity[Uart.parityLen++] = Uart.parityBits;        // and store them

                                        }
                                        if (Uart.len) {
                                        }
                                        if (Uart.len) {

-                                               return TRUE;                                                                                    // we are finished with decoding the raw data sequence
+                                               return true;                                            // we are finished with decoding the raw data sequence

                                        } else {
                                        } else {

-                                               UartReset();                                                                                    // Nothing received - try again
+                                               UartReset();                                            // Nothing received - start over

                                        }
                                }
                                        }
                                }

-                               if (Uart.state == STATE_START_OF_COMMUNICATION) {                               // error - must not follow directly after SOC
+                               if (Uart.state == STATE_START_OF_COMMUNICATION) {               // error - must not follow directly after SOC
+                                       LED_B_OFF();

                                        UartReset();
                                        UartReset();

-                                       Uart.highCnt = 6;
-                               } else {                                                                                                                // a logic "0"
+                               } else {                                                        // a logic "0"

                                        Uart.bitCount++;
                                        Uart.bitCount++;

-                                       Uart.shiftReg = (Uart.shiftReg >> 1);                                           // add a 0 to the shiftreg
+                                       Uart.shiftReg = (Uart.shiftReg >> 1);                       // add a 0 to the shiftreg

                                        Uart.state = STATE_MILLER_Y;
                                        Uart.state = STATE_MILLER_Y;

-                                       if(Uart.bitCount >= 9) {                                                                        // if we decoded a full byte (including parity)
+                                       if(Uart.bitCount >= 9) {                                    // if we decoded a full byte (including parity)

                                                Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
                                                Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);

-                                               Uart.parityBits <<= 1;                                                                  // make room for the parity bit
-                                               Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);               // store parity bit
+                                               Uart.parityBits <<= 1;                                  // make room for the parity bit
+                                               Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);       // store parity bit

                                                Uart.bitCount = 0;
                                                Uart.shiftReg = 0;
                                                Uart.bitCount = 0;
                                                Uart.shiftReg = 0;

-                                               if ((Uart.len&0x0007) == 0) {                                                   // every 8 data bytes
-                                                       Uart.parity[Uart.parityLen++] = Uart.parityBits;        // store 8 parity bits
+                                               if ((Uart.len&0x0007) == 0) {                           // every 8 data bytes
+                                                       Uart.parity[Uart.parityLen++] = Uart.parityBits;    // store 8 parity bits

                                                        Uart.parityBits = 0;
                                                }
                                        }
                                }
                        }
                }
                                                        Uart.parityBits = 0;
                                                }
                                        }
                                }
                        }
                }

-                       
-       } 

 
 

-    return FALSE;      // not finished yet, need more data
+       }
+
+       return false;   // not finished yet, need more data

 }
 
 
 }
 
 


@@ -440,10 +425,10 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
 // at the reader antenna will be modulated as well. The FPGA detects the modulation for us and would deliver e.g. the following:
 // ........ 0 0 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .......
 // The Manchester decoder needs to identify the following sequences:
 // at the reader antenna will be modulated as well. The FPGA detects the modulation for us and would deliver e.g. the following:
 // ........ 0 0 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .......
 // The Manchester decoder needs to identify the following sequences:

-// 4 ticks modulated followed by 4 ticks unmodulated:  Sequence D = 1 (also used as "start of communication")
-// 4 ticks unmodulated followed by 4 ticks modulated:  Sequence E = 0
-// 8 ticks unmodulated:                                                                        Sequence F = end of communication
-// 8 ticks modulated:                                                                  A collision. Save the collision position and treat as Sequence D
+// 4 ticks modulated followed by 4 ticks unmodulated:   Sequence D = 1 (also used as "start of communication")
+// 4 ticks unmodulated followed by 4 ticks modulated:   Sequence E = 0
+// 8 ticks unmodulated:                                 Sequence F = end of communication
+// 8 ticks modulated:                                   A collision. Save the collision position and treat as Sequence D

 // Note 1: the bitstream may start at any time. We therefore need to sync.
 // Note 2: parameter offset is used to determine the position of the parity bits (required for the anticollision command only)
 static tDemod Demod;
 // Note 1: the bitstream may start at any time. We therefore need to sync.
 // Note 2: parameter offset is used to determine the position of the parity bits (required for the anticollision command only)
 static tDemod Demod;


@@ -451,53 +436,49 @@ static tDemod Demod;
 // Lookup-Table to decide if 4 raw bits are a modulation.
 // We accept three or four "1" in any position
 const bool Mod_Manchester_LUT[] = {
 // Lookup-Table to decide if 4 raw bits are a modulation.
 // We accept three or four "1" in any position
 const bool Mod_Manchester_LUT[] = {

-       FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE,
-       FALSE, FALSE, FALSE, TRUE,  FALSE, TRUE,  TRUE,  TRUE
+       false, false, false, false, false, false, false, true,
+       false, false, false, true,  false, true,  true,  true

 };
 
 #define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4])
 #define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)])
 
 
 };
 
 #define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4])
 #define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)])
 
 

-void DemodReset()
-{
+static void DemodReset() {

        Demod.state = DEMOD_UNSYNCD;
        Demod.state = DEMOD_UNSYNCD;

-       Demod.len = 0;                                          // number of decoded data bytes
+       Demod.len = 0;                      // number of decoded data bytes

        Demod.parityLen = 0;
        Demod.parityLen = 0;

-       Demod.shiftReg = 0;                                     // shiftreg to hold decoded data bits
-       Demod.parityBits = 0;                           // 
-       Demod.collisionPos = 0;                         // Position of collision bit
-       Demod.twoBits = 0xffff;                         // buffer for 2 Bits
+       Demod.shiftReg = 0;                 // shiftreg to hold decoded data bits
+       Demod.parityBits = 0;               //
+       Demod.collisionPos = 0;             // Position of collision bit
+       Demod.twoBits = 0xffff;             // buffer for 2 Bits

        Demod.highCnt = 0;
        Demod.startTime = 0;
        Demod.endTime = 0;
 }
 
        Demod.highCnt = 0;
        Demod.startTime = 0;
        Demod.endTime = 0;
 }
 

-
-void DemodInit(uint8_t *data, uint8_t *parity)
-{
+static void DemodInit(uint8_t *data, uint8_t *parity) {

        Demod.output = data;
        Demod.parity = parity;
        DemodReset();
 }
 
 // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time
        Demod.output = data;
        Demod.parity = parity;
        DemodReset();
 }
 
 // use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time

-static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time)
-{
+static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time) {

 
        Demod.twoBits = (Demod.twoBits << 8) | bit;
 
        Demod.twoBits = (Demod.twoBits << 8) | bit;

-       
+

        if (Demod.state == DEMOD_UNSYNCD) {
 
        if (Demod.state == DEMOD_UNSYNCD) {
 

-               if (Demod.highCnt < 2) {                                                                                        // wait for a stable unmodulated signal
+               if (Demod.highCnt < 2) {                                            // wait for a stable unmodulated signal

                        if (Demod.twoBits == 0x0000) {
                                Demod.highCnt++;
                        } else {
                                Demod.highCnt = 0;
                        }
                } else {
                        if (Demod.twoBits == 0x0000) {
                                Demod.highCnt++;
                        } else {
                                Demod.highCnt = 0;
                        }
                } else {

-                       Demod.syncBit = 0xFFFF;                 // not set
-                       if              ((Demod.twoBits & 0x7700) == 0x7000) Demod.syncBit = 7; 
+                       Demod.syncBit = 0xFFFF;         // not set
+                       if      ((Demod.twoBits & 0x7700) == 0x7000) Demod.syncBit = 7;

                        else if ((Demod.twoBits & 0x3B80) == 0x3800) Demod.syncBit = 6;
                        else if ((Demod.twoBits & 0x1DC0) == 0x1C00) Demod.syncBit = 5;
                        else if ((Demod.twoBits & 0x0EE0) == 0x0E00) Demod.syncBit = 4;
                        else if ((Demod.twoBits & 0x3B80) == 0x3800) Demod.syncBit = 6;
                        else if ((Demod.twoBits & 0x1DC0) == 0x1C00) Demod.syncBit = 5;
                        else if ((Demod.twoBits & 0x0EE0) == 0x0E00) Demod.syncBit = 4;


@@ -508,72 +489,74 @@ static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non
                        if (Demod.syncBit != 0xFFFF) {
                                Demod.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
                                Demod.startTime -= Demod.syncBit;
                        if (Demod.syncBit != 0xFFFF) {
                                Demod.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
                                Demod.startTime -= Demod.syncBit;

-                               Demod.bitCount = offset;                        // number of decoded data bits
+                               Demod.bitCount = offset;            // number of decoded data bits

                                Demod.state = DEMOD_MANCHESTER_DATA;
                                Demod.state = DEMOD_MANCHESTER_DATA;

+                               LED_C_ON();

                        }
                }
 
        } else {
 
                        }
                }
 
        } else {
 

-               if (IsManchesterModulationNibble1(Demod.twoBits >> Demod.syncBit)) {            // modulation in first half
-                       if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {    // ... and in second half = collision
+               if (IsManchesterModulationNibble1(Demod.twoBits >> Demod.syncBit)) {        // modulation in first half
+                       if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {    // ... and in second half = collision

                                if (!Demod.collisionPos) {
                                        Demod.collisionPos = (Demod.len << 3) + Demod.bitCount;
                                }
                                if (!Demod.collisionPos) {
                                        Demod.collisionPos = (Demod.len << 3) + Demod.bitCount;
                                }

-                       }                                                                                                                       // modulation in first half only - Sequence D = 1
+                       }                                                           // modulation in first half only - Sequence D = 1

                        Demod.bitCount++;
                        Demod.bitCount++;

-                       Demod.shiftReg = (Demod.shiftReg >> 1) | 0x100;                         // in both cases, add a 1 to the shiftreg
-                       if(Demod.bitCount == 9) {                                                                       // if we decoded a full byte (including parity)
+                       Demod.shiftReg = (Demod.shiftReg >> 1) | 0x100;             // in both cases, add a 1 to the shiftreg
+                       if(Demod.bitCount == 9) {                                   // if we decoded a full byte (including parity)

                                Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);
                                Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);

-                               Demod.parityBits <<= 1;                                                                 // make room for the parity bit
-                               Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01);     // store parity bit
+                               Demod.parityBits <<= 1;                                 // make room for the parity bit
+                               Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01);     // store parity bit

                                Demod.bitCount = 0;
                                Demod.shiftReg = 0;
                                Demod.bitCount = 0;
                                Demod.shiftReg = 0;

-                               if((Demod.len&0x0007) == 0) {                                                   // every 8 data bytes
-                                       Demod.parity[Demod.parityLen++] = Demod.parityBits;     // store 8 parity bits
+                               if((Demod.len&0x0007) == 0) {                           // every 8 data bytes
+                                       Demod.parity[Demod.parityLen++] = Demod.parityBits; // store 8 parity bits

                                        Demod.parityBits = 0;
                                }
                        }
                        Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1) - 4;
                                        Demod.parityBits = 0;
                                }
                        }
                        Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1) - 4;

-               } else {                                                                                                                // no modulation in first half
-                       if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {    // and modulation in second half = Sequence E = 0
+               } else {                                                        // no modulation in first half
+                       if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {    // and modulation in second half = Sequence E = 0

                                Demod.bitCount++;
                                Demod.bitCount++;

-                               Demod.shiftReg = (Demod.shiftReg >> 1);                                 // add a 0 to the shiftreg
-                               if(Demod.bitCount >= 9) {                                                               // if we decoded a full byte (including parity)
+                               Demod.shiftReg = (Demod.shiftReg >> 1);                 // add a 0 to the shiftreg
+                               if(Demod.bitCount >= 9) {                               // if we decoded a full byte (including parity)

                                        Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);
                                        Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);

-                                       Demod.parityBits <<= 1;                                                         // make room for the new parity bit
+                                       Demod.parityBits <<= 1;                             // make room for the new parity bit

                                        Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); // store parity bit
                                        Demod.bitCount = 0;
                                        Demod.shiftReg = 0;
                                        Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); // store parity bit
                                        Demod.bitCount = 0;
                                        Demod.shiftReg = 0;

-                                       if ((Demod.len&0x0007) == 0) {                                          // every 8 data bytes
-                                               Demod.parity[Demod.parityLen++] = Demod.parityBits;     // store 8 parity bits1
+                                       if ((Demod.len&0x0007) == 0) {                      // every 8 data bytes
+                                               Demod.parity[Demod.parityLen++] = Demod.parityBits; // store 8 parity bits1

                                                Demod.parityBits = 0;
                                        }
                                }
                                Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1);
                                                Demod.parityBits = 0;
                                        }
                                }
                                Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1);

-                       } else {                                                                                                        // no modulation in both halves - End of communication
-                               if(Demod.bitCount > 0) {                                                                // there are some remaining data bits
-                                       Demod.shiftReg >>= (9 - Demod.bitCount);                        // right align the decoded bits
-                                       Demod.output[Demod.len++] = Demod.shiftReg & 0xff;      // and add them to the output
-                                       Demod.parityBits <<= 1;                                                         // add a (void) parity bit
-                                       Demod.parityBits <<= (8 - (Demod.len&0x0007));          // left align remaining parity bits
-                                       Demod.parity[Demod.parityLen++] = Demod.parityBits;     // and store them
-                                       return TRUE;
-                               } else if (Demod.len & 0x0007) {                                                // there are some parity bits to store
-                                       Demod.parityBits <<= (8 - (Demod.len&0x0007));          // left align remaining parity bits
-                                       Demod.parity[Demod.parityLen++] = Demod.parityBits;     // and store them
+                       } else {                                                    // no modulation in both halves - End of communication
+                               LED_C_OFF();
+                               if(Demod.bitCount > 0) {                                // there are some remaining data bits
+                                       Demod.shiftReg >>= (9 - Demod.bitCount);            // right align the decoded bits
+                                       Demod.output[Demod.len++] = Demod.shiftReg & 0xff;  // and add them to the output
+                                       Demod.parityBits <<= 1;                             // add a (void) parity bit
+                                       Demod.parityBits <<= (8 - (Demod.len&0x0007));      // left align remaining parity bits
+                                       Demod.parity[Demod.parityLen++] = Demod.parityBits; // and store them
+                                       return true;
+                               } else if (Demod.len & 0x0007) {                        // there are some parity bits to store
+                                       Demod.parityBits <<= (8 - (Demod.len&0x0007));      // left align remaining parity bits
+                                       Demod.parity[Demod.parityLen++] = Demod.parityBits; // and store them

                                }
                                if (Demod.len) {
                                }
                                if (Demod.len) {

-                                       return TRUE;                                                                            // we are finished with decoding the raw data sequence
-                               } else {                                                                                                // nothing received. Start over
+                                       return true;                                        // we are finished with decoding the raw data sequence
+                               } else {                                                // nothing received. Start over

                                        DemodReset();
                                }
                        }
                }
                                        DemodReset();
                                }
                        }
                }

-                       
-       } 

 
 

-    return FALSE;      // not finished yet, need more data
+       }
+
+       return false;   // not finished yet, need more data

 }
 
 //=============================================================================
 }
 
 //=============================================================================


@@ -590,61 +573,61 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
        // param:
        // bit 0 - trigger from first card answer
        // bit 1 - trigger from first reader 7-bit request
        // param:
        // bit 0 - trigger from first card answer
        // bit 1 - trigger from first reader 7-bit request

-       
+

        LEDsoff();
        LEDsoff();

-       // init trace buffer
-       iso14a_clear_trace();
-       iso14a_set_tracing(TRUE);
+       LED_A_ON();
+
+       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+       // Allocate memory from BigBuf for some buffers
+       // free all previous allocations first
+       BigBuf_free();

 
 

-       // We won't start recording the frames that we acquire until we trigger;
-       // a good trigger condition to get started is probably when we see a
-       // response from the tag.
-       // triggered == FALSE -- to wait first for card
-       bool triggered = !(param & 0x03); 
-       

        // The command (reader -> tag) that we're receiving.
        // The command (reader -> tag) that we're receiving.

-       // The length of a received command will in most cases be no more than 18 bytes.
-       // So 32 should be enough!
-       uint8_t *receivedCmd = ((uint8_t *)BigBuf) + RECV_CMD_OFFSET;
-       uint8_t *receivedCmdPar = ((uint8_t *)BigBuf) + RECV_CMD_PAR_OFFSET;
-       
+       uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+       uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+

        // The response (tag -> reader) that we're receiving.
        // The response (tag -> reader) that we're receiving.

-       uint8_t *receivedResponse = ((uint8_t *)BigBuf) + RECV_RESP_OFFSET;
-       uint8_t *receivedResponsePar = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET;
-       
-       // As we receive stuff, we copy it from receivedCmd or receivedResponse
-       // into trace, along with its length and other annotations.
-       //uint8_t *trace = (uint8_t *)BigBuf;
-       
+       uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
+       uint8_t *receivedResponsePar = BigBuf_malloc(MAX_PARITY_SIZE);
+

        // The DMA buffer, used to stream samples from the FPGA
        // The DMA buffer, used to stream samples from the FPGA

-       uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET;
+       uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+
+       // init trace buffer
+       clear_trace();
+       set_tracing(true);
+

        uint8_t *data = dmaBuf;
        uint8_t previous_data = 0;
        int maxDataLen = 0;
        int dataLen = 0;
        uint8_t *data = dmaBuf;
        uint8_t previous_data = 0;
        int maxDataLen = 0;
        int dataLen = 0;

-       bool TagIsActive = FALSE;
-       bool ReaderIsActive = FALSE;
-       
-       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+       bool TagIsActive = false;
+       bool ReaderIsActive = false;

 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);
 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);

-       
+

        // Set up the demodulator for the reader -> tag commands
        UartInit(receivedCmd, receivedCmdPar);
        // Set up the demodulator for the reader -> tag commands
        UartInit(receivedCmd, receivedCmdPar);

-       
+

        // Setup and start DMA.
        FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
        // Setup and start DMA.
        FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);

-       
+
+       // We won't start recording the frames that we acquire until we trigger;
+       // a good trigger condition to get started is probably when we see a
+       // response from the tag.
+       // triggered == false -- to wait first for card
+       bool triggered = !(param & 0x03);
+

        // And now we loop, receiving samples.
        // And now we loop, receiving samples.

-       for(uint32_t rsamples = 0; TRUE; ) {
+       for (uint32_t rsamples = 0; true; ) {

 
 

-               if(BUTTON_PRESS()) {
+               if (BUTTON_PRESS()) {

                        DbpString("cancelled by button");
                        break;
                }
 
                        DbpString("cancelled by button");
                        break;
                }
 

-               LED_A_ON();

                WDT_HIT();
 
                int register readBufDataP = data - dmaBuf;
                WDT_HIT();
 
                int register readBufDataP = data - dmaBuf;


@@ -657,7 +640,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
                // test for length of buffer
                if(dataLen > maxDataLen) {
                        maxDataLen = dataLen;
                // test for length of buffer
                if(dataLen > maxDataLen) {
                        maxDataLen = dataLen;

-                       if(dataLen > 400) {
+                       if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {

                                Dbprintf("blew circular buffer! dataLen=%d", dataLen);
                                break;
                        }
                                Dbprintf("blew circular buffer! dataLen=%d", dataLen);
                                break;
                        }


@@ -676,54 +659,47 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
                        AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
                }
 
                        AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
                }
 

-               LED_A_OFF();
-               
-               if (rsamples & 0x01) {                          // Need two samples to feed Miller and Manchester-Decoder
+               if (rsamples & 0x01) {              // Need two samples to feed Miller and Manchester-Decoder

 
 

-                       if(!TagIsActive) {              // no need to try decoding reader data if the tag is sending
+                       if(!TagIsActive) {      // no need to try decoding reader data if the tag is sending

                                uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
                                if (MillerDecoding(readerdata, (rsamples-1)*4)) {
                                uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
                                if (MillerDecoding(readerdata, (rsamples-1)*4)) {

-                                       LED_C_ON();
-

                                        // check - if there is a short 7bit request from reader
                                        // check - if there is a short 7bit request from reader

-                                       if ((!triggered) && (param & 0x02) && (Uart.len == 1) && (Uart.bitCount == 7)) triggered = TRUE;
-
+                                       if ((!triggered) && (param & 0x02) && (Uart.len == 1) && (Uart.bitCount == 7)) {
+                                               triggered = true;
+                                       }

                                        if(triggered) {
                                        if(triggered) {

-                                               if (!LogTrace(receivedCmd, 
-                                                                               Uart.len, 
+                                               if (!LogTrace(receivedCmd,
+                                                                               Uart.len,

                                                                                Uart.startTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
                                                                                Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
                                                                                Uart.startTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
                                                                                Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,

-                                                                               Uart.parity, 
-                                                                               TRUE)) break;
+                                                                               Uart.parity,
+                                                                               true)) break;

                                        }
                                        /* And ready to receive another command. */
                                        UartReset();
                                        /* And also reset the demod code, which might have been */
                                        /* false-triggered by the commands from the reader. */
                                        DemodReset();
                                        }
                                        /* And ready to receive another command. */
                                        UartReset();
                                        /* And also reset the demod code, which might have been */
                                        /* false-triggered by the commands from the reader. */
                                        DemodReset();

-                                       LED_B_OFF();

                                }
                                ReaderIsActive = (Uart.state != STATE_UNSYNCD);
                        }
 
                                }
                                ReaderIsActive = (Uart.state != STATE_UNSYNCD);
                        }
 

-                       if(!ReaderIsActive) {           // no need to try decoding tag data if the reader is sending - and we cannot afford the time
+                       if (!ReaderIsActive) {      // no need to try decoding tag data if the reader is sending - and we cannot afford the time

                                uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
                                uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);

-                               if(ManchesterDecoding(tagdata, 0, (rsamples-1)*4)) {
-                                       LED_B_ON();
-
-                                       if (!LogTrace(receivedResponse, 
-                                                                       Demod.len, 
-                                                                       Demod.startTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER, 
+                               if (ManchesterDecoding(tagdata, 0, (rsamples-1)*4)) {
+                                       if (!LogTrace(receivedResponse,
+                                                                       Demod.len,
+                                                                       Demod.startTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER,

                                                                        Demod.endTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER,
                                                                        Demod.parity,
                                                                        Demod.endTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER,
                                                                        Demod.parity,

-                                                                       FALSE)) break;
-
-                                       if ((!triggered) && (param & 0x01)) triggered = TRUE;
-
+                                                                       false)) break;
+                                       if ((!triggered) && (param & 0x01)) triggered = true;

                                        // And ready to receive another response.
                                        DemodReset();
                                        // And ready to receive another response.
                                        DemodReset();

-                                       LED_C_OFF();
-                               } 
+                                       // And reset the Miller decoder including itS (now outdated) input buffer
+                                       UartInit(receivedCmd, receivedCmdPar);
+                               }

                                TagIsActive = (Demod.state != DEMOD_UNSYNCD);
                        }
                }
                                TagIsActive = (Demod.state != DEMOD_UNSYNCD);
                        }
                }


@@ -736,19 +712,18 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
                }
        } // main cycle
 
                }
        } // main cycle
 

-       DbpString("COMMAND FINISHED");
-

        FpgaDisableSscDma();
        FpgaDisableSscDma();

-       Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len);
-       Dbprintf("traceLen=%d, Uart.output[0]=%08x", traceLen, (uint32_t)Uart.output[0]);

        LEDsoff();
        LEDsoff();

+
+       DbpString("COMMAND FINISHED");
+       Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len);
+       Dbprintf("traceLen=%d, Uart.output[0]=%08x", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]);

 }
 
 //-----------------------------------------------------------------------------
 // Prepare tag messages
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------
 // Prepare tag messages
 //-----------------------------------------------------------------------------

-static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity)
-{
+static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity) {

        ToSendReset();
 
        // Correction bit, might be removed when not needed
        ToSendReset();
 
        // Correction bit, might be removed when not needed


@@ -760,17 +735,16 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *par
        ToSendStuffBit(0);
        ToSendStuffBit(0);
        ToSendStuffBit(0);
        ToSendStuffBit(0);
        ToSendStuffBit(0);
        ToSendStuffBit(0);

-       
+

        // Send startbit
        ToSend[++ToSendMax] = SEC_D;
        // Send startbit
        ToSend[++ToSendMax] = SEC_D;

-       

        LastProxToAirDuration = 8 * ToSendMax - 4;
 
        LastProxToAirDuration = 8 * ToSendMax - 4;
 

-       for(uint16_t i = 0; i < len; i++) {
+       for (uint16_t i = 0; i < len; i++) {

                uint8_t b = cmd[i];
 
                // Data bits
                uint8_t b = cmd[i];
 
                // Data bits

-               for(uint16_t j = 0; j < 8; j++) {
+               for (uint16_t j = 0; j < 8; j++) {

                        if(b & 1) {
                                ToSend[++ToSendMax] = SEC_D;
                        } else {
                        if(b & 1) {
                                ToSend[++ToSendMax] = SEC_D;
                        } else {


@@ -796,17 +770,8 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *par
        ToSendMax++;
 }
 
        ToSendMax++;
 }
 

-static void CodeIso14443aAsTag(const uint8_t *cmd, uint16_t len)
-{
-       uint8_t par[MAX_PARITY_SIZE];
-       
-       GetParity(cmd, len, par);
-       CodeIso14443aAsTagPar(cmd, len, par);
-}
-

 
 

-static void Code4bitAnswerAsTag(uint8_t cmd)
-{
+static void Code4bitAnswerAsTag(uint8_t cmd) {

        int i;
 
        ToSendReset();
        int i;
 
        ToSendReset();


@@ -825,7 +790,7 @@ static void Code4bitAnswerAsTag(uint8_t cmd)
        ToSend[++ToSendMax] = SEC_D;
 
        uint8_t b = cmd;
        ToSend[++ToSendMax] = SEC_D;
 
        uint8_t b = cmd;

-       for(i = 0; i < 4; i++) {
+       for (i = 0; i < 4; i++) {

                if(b & 1) {
                        ToSend[++ToSendMax] = SEC_D;
                        LastProxToAirDuration = 8 * ToSendMax - 4;
                if(b & 1) {
                        ToSend[++ToSendMax] = SEC_D;
                        LastProxToAirDuration = 8 * ToSendMax - 4;


@@ -843,65 +808,80 @@ static void Code4bitAnswerAsTag(uint8_t cmd)
        ToSendMax++;
 }
 
        ToSendMax++;
 }
 

+
+static uint8_t *LastReaderTraceTime = NULL;
+
+static void EmLogTraceReader(void) {
+       // remember last reader trace start to fix timing info later
+       LastReaderTraceTime = BigBuf_get_addr() + BigBuf_get_traceLen();
+       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, true);
+}
+
+
+static void FixLastReaderTraceTime(uint32_t tag_StartTime) {
+       uint32_t reader_EndTime = Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG;
+       uint32_t reader_StartTime = Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG;
+       uint16_t reader_modlen = reader_EndTime - reader_StartTime;
+       uint16_t approx_fdt = tag_StartTime - reader_EndTime;
+       uint16_t exact_fdt = (approx_fdt - 20 + 32)/64 * 64 + 20;
+       reader_StartTime = tag_StartTime - exact_fdt - reader_modlen;
+       LastReaderTraceTime[0] = (reader_StartTime >> 0) & 0xff;
+       LastReaderTraceTime[1] = (reader_StartTime >> 8) & 0xff;
+       LastReaderTraceTime[2] = (reader_StartTime >> 16) & 0xff;
+       LastReaderTraceTime[3] = (reader_StartTime >> 24) & 0xff;
+}
+
+
+static void EmLogTraceTag(uint8_t *tag_data, uint16_t tag_len, uint8_t *tag_Parity, uint32_t ProxToAirDuration) {
+       uint32_t tag_StartTime = LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG;
+       uint32_t tag_EndTime = (LastTimeProxToAirStart + ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG;
+       LogTrace(tag_data, tag_len, tag_StartTime, tag_EndTime, tag_Parity, false);
+       FixLastReaderTraceTime(tag_StartTime);
+}
+
+

 //-----------------------------------------------------------------------------
 // Wait for commands from reader
 // Stop when button is pressed
 //-----------------------------------------------------------------------------
 // Wait for commands from reader
 // Stop when button is pressed

-// Or return TRUE when command is captured
+// Or return true when command is captured

 //-----------------------------------------------------------------------------
 //-----------------------------------------------------------------------------

-static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len)
-{
-    // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
-    // only, since we are receiving, not transmitting).
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len) {
+       // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
+       // only, since we are receiving, not transmitting).
+       // Signal field is off with the appropriate LED
+       LED_D_OFF();
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);

 
 

-    // Now run a `software UART' on the stream of incoming samples.
+       // Now run a `software UART' on the stream of incoming samples.

        UartInit(received, parity);
 
        // clear RXRDY:
        UartInit(received, parity);
 
        // clear RXRDY:

-    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+       uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+
+       for (;;) {
+               WDT_HIT();

 
 

-    for(;;) {
-        WDT_HIT();
+               if(BUTTON_PRESS()) return false;

 
 

-        if(BUTTON_PRESS()) return FALSE;
-               
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;

                        if(MillerDecoding(b, 0)) {
                                *len = Uart.len;
                        if(MillerDecoding(b, 0)) {
                                *len = Uart.len;

-                               return TRUE;
+                               EmLogTraceReader();
+                               return true;

                        }
                        }

-               }
-    }
+               }
+       }

 }
 
 }
 

-static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNeeded);
-int EmSend4bitEx(uint8_t resp, bool correctionNeeded);
+

 int EmSend4bit(uint8_t resp);
 int EmSend4bit(uint8_t resp);

-int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, bool correctionNeeded, uint8_t *par);
-int EmSendCmdEx(uint8_t *resp, uint16_t respLen, bool correctionNeeded);
+static int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, uint8_t *par);

 int EmSendCmd(uint8_t *resp, uint16_t respLen);
 int EmSendCmd(uint8_t *resp, uint16_t respLen);

-int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par);
-bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint8_t *reader_Parity,
-                                uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_t *tag_Parity);
+int EmSendPrecompiledCmd(tag_response_info_t *response_info);

 
 

-static uint8_t* free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
-
-typedef struct {
-  uint8_t* response;
-  size_t   response_n;
-  uint8_t* modulation;
-  size_t   modulation_n;
-  uint32_t ProxToAirDuration;
-} tag_response_info_t;
-
-void reset_free_buffer() {
-  free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
-}

 
 

-bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) {
+static bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) {

        // Example response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes
        // This will need the following byte array for a modulation sequence
        //    144        data bits (18 * 8)
        // Example response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes
        // This will need the following byte array for a modulation sequence
        //    144        data bits (18 * 8)


@@ -912,41 +892,49 @@ bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffe
        // ----------- +
        //    166 bytes, since every bit that needs to be send costs us a byte
        //
        // ----------- +
        //    166 bytes, since every bit that needs to be send costs us a byte
        //

-  
+
+

   // Prepare the tag modulation bits from the message
   // Prepare the tag modulation bits from the message

-  CodeIso14443aAsTag(response_info->response,response_info->response_n);
-  
+  GetParity(response_info->response, response_info->response_n, &(response_info->par));
+  CodeIso14443aAsTagPar(response_info->response,response_info->response_n, &(response_info->par));
+

   // Make sure we do not exceed the free buffer space
   if (ToSendMax > max_buffer_size) {
   // Make sure we do not exceed the free buffer space
   if (ToSendMax > max_buffer_size) {

-    Dbprintf("Out of memory, when modulating bits for tag answer:");
-    Dbhexdump(response_info->response_n,response_info->response,false);
-    return false;
+       Dbprintf("Out of memory, when modulating bits for tag answer:");
+       Dbhexdump(response_info->response_n, response_info->response, false);
+       return false;

   }
   }

-  
+

   // Copy the byte array, used for this modulation to the buffer position
   // Copy the byte array, used for this modulation to the buffer position

-  memcpy(response_info->modulation,ToSend,ToSendMax);
-  
+  memcpy(response_info->modulation, ToSend, ToSendMax);
+

   // Store the number of bytes that were used for encoding/modulation and the time needed to transfer them
   response_info->modulation_n = ToSendMax;
   response_info->ProxToAirDuration = LastProxToAirDuration;
   // Store the number of bytes that were used for encoding/modulation and the time needed to transfer them
   response_info->modulation_n = ToSendMax;
   response_info->ProxToAirDuration = LastProxToAirDuration;

-  
+

   return true;
 }
 
   return true;
 }
 

-bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
+
+// "precompile" responses. There are 7 predefined responses with a total of 28 bytes data to transmit.
+// Coded responses need one byte per bit to transfer (data, parity, start, stop, correction)
+// 28 * 8 data bits, 28 * 1 parity bits, 7 start bits, 7 stop bits, 7 correction bits for the modulation
+// -> need 273 bytes buffer
+#define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 273
+
+bool prepare_allocated_tag_modulation(tag_response_info_t* response_info, uint8_t **buffer, size_t *max_buffer_size) {
+

   // Retrieve and store the current buffer index
   // Retrieve and store the current buffer index

-  response_info->modulation = free_buffer_pointer;
-  
-  // Determine the maximum size we can use from our buffer
-  size_t max_buffer_size = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + FREE_BUFFER_SIZE) - free_buffer_pointer;
-  
+  response_info->modulation = *buffer;
+

   // Forward the prepare tag modulation function to the inner function
   // Forward the prepare tag modulation function to the inner function

-  if (prepare_tag_modulation(response_info,max_buffer_size)) {
-    // Update the free buffer offset
-    free_buffer_pointer += ToSendMax;
-    return true;
+  if (prepare_tag_modulation(response_info, *max_buffer_size)) {
+       // Update the free buffer offset and the remaining buffer size
+       *buffer += ToSendMax;
+       *max_buffer_size -= ToSendMax;
+       return true;

   } else {
   } else {

-    return false;
+       return false;

   }
 }
 
   }
 }
 


@@ -954,17 +942,13 @@ bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
 // Main loop of simulated tag: receive commands from reader, decide what
 // response to send, and send it.
 //-----------------------------------------------------------------------------
 // Main loop of simulated tag: receive commands from reader, decide what
 // response to send, and send it.
 //-----------------------------------------------------------------------------

-void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
-{
-       // Enable and clear the trace
-       iso14a_clear_trace();
-       iso14a_set_tracing(TRUE);
+void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) {

 
        uint8_t sak;
 
        // The first response contains the ATQA (note: bytes are transmitted in reverse order).
        uint8_t response1[2];
 
        uint8_t sak;
 
        // The first response contains the ATQA (note: bytes are transmitted in reverse order).
        uint8_t response1[2];

-       
+

        switch (tagType) {
                case 1: { // MIFARE Classic
                        // Says: I am Mifare 1k - original line
        switch (tagType) {
                case 1: { // MIFARE Classic
                        // Says: I am Mifare 1k - original line


@@ -990,17 +974,24 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                        response1[1] = 0x00;
                        sak = 0x28;
                } break;
                        response1[1] = 0x00;
                        sak = 0x28;
                } break;

+               case 5: { // MIFARE TNP3XXX
+                       // Says: I am a toy
+                       response1[0] = 0x01;
+                       response1[1] = 0x0f;
+                       sak = 0x01;
+               } break;

                default: {
                        Dbprintf("Error: unkown tagtype (%d)",tagType);
                        return;
                } break;
        }
                default: {
                        Dbprintf("Error: unkown tagtype (%d)",tagType);
                        return;
                } break;
        }

-       
+

        // The second response contains the (mandatory) first 24 bits of the UID
        // The second response contains the (mandatory) first 24 bits of the UID

-       uint8_t response2[5];
+       uint8_t response2[5] = {0x00};

 
        // Check if the uid uses the (optional) part
 
        // Check if the uid uses the (optional) part

-       uint8_t response2a[5];
+       uint8_t response2a[5] = {0x00};
+

        if (uid_2nd) {
                response2[0] = 0x88;
                num_to_bytes(uid_1st,3,response2+1);
        if (uid_2nd) {
                response2[0] = 0x88;
                num_to_bytes(uid_1st,3,response2+1);


@@ -1021,18 +1012,18 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
        response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
 
        // Prepare the mandatory SAK (for 4 and 7 byte UID)
        response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
 
        // Prepare the mandatory SAK (for 4 and 7 byte UID)

-       uint8_t response3[3];
+       uint8_t response3[3]  = {0x00};

        response3[0] = sak;
        ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
 
        // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit
        response3[0] = sak;
        ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
 
        // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit

-       uint8_t response3a[3];
+       uint8_t response3a[3]  = {0x00};

        response3a[0] = sak & 0xFB;
        ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
 
        uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
        response3a[0] = sak & 0xFB;
        ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
 
        uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce

-       uint8_t response6[] = { 0x04, 0x58, 0x80, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS: 
-       // Format byte = 0x58: FSCI=0x08 (FSC=256), TA(1) and TC(1) present, 
+       uint8_t response6[] = { 0x04, 0x58, 0x80, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS:
+       // Format byte = 0x58: FSCI=0x08 (FSC=256), TA(1) and TC(1) present,

        // TA(1) = 0x80: different divisors not supported, DR = 1, DS = 1
        // TB(1) = not present. Defaults: FWI = 4 (FWT = 256 * 16 * 2^4 * 1/fc = 4833us), SFGI = 0 (SFG = 256 * 16 * 2^0 * 1/fc = 302us)
        // TC(1) = 0x02: CID supported, NAD not supported
        // TA(1) = 0x80: different divisors not supported, DR = 1, DS = 1
        // TB(1) = not present. Defaults: FWI = 4 (FWT = 256 * 16 * 2^4 * 1/fc = 4833us), SFGI = 0 (SFG = 256 * 16 * 2^0 * 1/fc = 302us)
        // TC(1) = 0x02: CID supported, NAD not supported


@@ -1061,14 +1052,25 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                .modulation = dynamic_modulation_buffer,
                .modulation_n = 0
        };
                .modulation = dynamic_modulation_buffer,
                .modulation_n = 0
        };

-  
-       // Reset the offset pointer of the free buffer
-       reset_free_buffer();
-  
+
+       // We need to listen to the high-frequency, peak-detected path.
+       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+       BigBuf_free_keep_EM();
+
+       // allocate buffers:
+       uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+       uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+       uint8_t *free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE);
+       size_t free_buffer_size = ALLOCATED_TAG_MODULATION_BUFFER_SIZE;
+       // clear trace
+       clear_trace();
+       set_tracing(true);
+

        // Prepare the responses of the anticollision phase
        // there will be not enough time to do this at the moment the reader sends it REQA
        for (size_t i=0; i<TAG_RESPONSE_COUNT; i++) {
        // Prepare the responses of the anticollision phase
        // there will be not enough time to do this at the moment the reader sends it REQA
        for (size_t i=0; i<TAG_RESPONSE_COUNT; i++) {

-               prepare_allocated_tag_modulation(&responses[i]);
+               prepare_allocated_tag_modulation(&responses[i], &free_buffer_pointer, &free_buffer_size);

        }
 
        int len = 0;
        }
 
        int len = 0;


@@ -1082,65 +1084,50 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
        int happened2 = 0;
        int cmdsRecvd = 0;
 
        int happened2 = 0;
        int cmdsRecvd = 0;
 

-       // We need to listen to the high-frequency, peak-detected path.
-       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
-       // buffers used on software Uart:
-       uint8_t *receivedCmd = ((uint8_t *)BigBuf) + RECV_CMD_OFFSET;
-       uint8_t *receivedCmdPar = ((uint8_t *)BigBuf) + RECV_CMD_PAR_OFFSET;
-

        cmdsRecvd = 0;
        tag_response_info_t* p_response;
 
        LED_A_ON();
        cmdsRecvd = 0;
        tag_response_info_t* p_response;
 
        LED_A_ON();

-       for(;;) {
+       for (;;) {

                // Clean receive command buffer
                // Clean receive command buffer

-               

                if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
                        DbpString("Button press");
                        break;
                }
 
                p_response = NULL;
                if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
                        DbpString("Button press");
                        break;
                }
 
                p_response = NULL;

-               
+

                // Okay, look at the command now.
                lastorder = order;
                if(receivedCmd[0] == 0x26) { // Received a REQUEST
                        p_response = &responses[0]; order = 1;
                } else if(receivedCmd[0] == 0x52) { // Received a WAKEUP
                        p_response = &responses[0]; order = 6;
                // Okay, look at the command now.
                lastorder = order;
                if(receivedCmd[0] == 0x26) { // Received a REQUEST
                        p_response = &responses[0]; order = 1;
                } else if(receivedCmd[0] == 0x52) { // Received a WAKEUP
                        p_response = &responses[0]; order = 6;

-               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) {   // Received request for UID (cascade 1)
+               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) {   // Received request for UID (cascade 1)

                        p_response = &responses[1]; order = 2;
                        p_response = &responses[1]; order = 2;

-               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) {   // Received request for UID (cascade 2)
+               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) {   // Received request for UID (cascade 2)

                        p_response = &responses[2]; order = 20;
                        p_response = &responses[2]; order = 20;

-               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x93) {   // Received a SELECT (cascade 1)
+               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x93) {   // Received a SELECT (cascade 1)

                        p_response = &responses[3]; order = 3;
                        p_response = &responses[3]; order = 3;

-               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x95) {   // Received a SELECT (cascade 2)
+               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x95) {   // Received a SELECT (cascade 2)

                        p_response = &responses[4]; order = 30;
                        p_response = &responses[4]; order = 30;

-               } else if(receivedCmd[0] == 0x30) {     // Received a (plain) READ
-                       EmSendCmdEx(data+(4*receivedCmd[1]),16,false);
+               } else if(receivedCmd[0] == 0x30) { // Received a (plain) READ
+                       EmSendCmd(data+(4*receivedCmd[1]),16);

                        // Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
                        // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
                        p_response = NULL;
                        // Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
                        // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
                        p_response = NULL;

-               } else if(receivedCmd[0] == 0x50) {     // Received a HALT
-//                     DbpString("Reader requested we HALT!:");
-                       if (tracing) {
-                               LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                       }
+               } else if(receivedCmd[0] == 0x50) { // Received a HALT

                        p_response = NULL;
                        p_response = NULL;

-               } else if(receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61) {   // Received an authentication request
+               } else if(receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61) {   // Received an authentication request

                        p_response = &responses[5]; order = 7;
                        p_response = &responses[5]; order = 7;

-               } else if(receivedCmd[0] == 0xE0) {     // Received a RATS request
-                       if (tagType == 1 || tagType == 2) {     // RATS not supported
+               } else if(receivedCmd[0] == 0xE0) { // Received a RATS request
+                       if (tagType == 1 || tagType == 2) { // RATS not supported

                                EmSend4bit(CARD_NACK_NA);
                                p_response = NULL;
                        } else {
                                p_response = &responses[6]; order = 70;
                        }
                } else if (order == 7 && len == 8) { // Received {nr] and {ar} (part of authentication)
                                EmSend4bit(CARD_NACK_NA);
                                p_response = NULL;
                        } else {
                                p_response = &responses[6]; order = 70;
                        }
                } else if (order == 7 && len == 8) { // Received {nr] and {ar} (part of authentication)

-                       if (tracing) {
-                               LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                       }

                        uint32_t nr = bytes_to_num(receivedCmd,4);
                        uint32_t ar = bytes_to_num(receivedCmd+4,4);
                        Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
                        uint32_t nr = bytes_to_num(receivedCmd,4);
                        uint32_t ar = bytes_to_num(receivedCmd+4,4);
                        Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);


@@ -1168,7 +1155,7 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                                  dynamic_response_info.response[0] = receivedCmd[0] ^ 0x11;
                                  dynamic_response_info.response_n = 2;
                                } break;
                                  dynamic_response_info.response[0] = receivedCmd[0] ^ 0x11;
                                  dynamic_response_info.response_n = 2;
                                } break;

-                                 
+

                                case 0xBA: { //
                                  memcpy(dynamic_response_info.response,"\xAB\x00",2);
                                  dynamic_response_info.response_n = 2;
                                case 0xBA: { //
                                  memcpy(dynamic_response_info.response,"\xAB\x00",2);
                                  dynamic_response_info.response_n = 2;


@@ -1182,16 +1169,13 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
 
                                default: {
                                        // Never seen this command before
 
                                default: {
                                        // Never seen this command before

-                                       if (tracing) {
-                                               LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       }

                                        Dbprintf("Received unknown command (len=%d):",len);
                                        Dbhexdump(len,receivedCmd,false);
                                        // Do not respond
                                        dynamic_response_info.response_n = 0;
                                } break;
                        }
                                        Dbprintf("Received unknown command (len=%d):",len);
                                        Dbhexdump(len,receivedCmd,false);
                                        // Do not respond
                                        dynamic_response_info.response_n = 0;
                                } break;
                        }

-      
+

                        if (dynamic_response_info.response_n > 0) {
                                // Copy the CID from the reader query
                                dynamic_response_info.response[1] = receivedCmd[1];
                        if (dynamic_response_info.response_n > 0) {
                                // Copy the CID from the reader query
                                dynamic_response_info.response[1] = receivedCmd[1];


@@ -1199,12 +1183,9 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                                // Add CRC bytes, always used in ISO 14443A-4 compliant cards
                                AppendCrc14443a(dynamic_response_info.response,dynamic_response_info.response_n);
                                dynamic_response_info.response_n += 2;
                                // Add CRC bytes, always used in ISO 14443A-4 compliant cards
                                AppendCrc14443a(dynamic_response_info.response,dynamic_response_info.response_n);
                                dynamic_response_info.response_n += 2;

-        
+

                                if (prepare_tag_modulation(&dynamic_response_info,DYNAMIC_MODULATION_BUFFER_SIZE) == false) {
                                        Dbprintf("Error preparing tag response");
                                if (prepare_tag_modulation(&dynamic_response_info,DYNAMIC_MODULATION_BUFFER_SIZE) == false) {
                                        Dbprintf("Error preparing tag response");

-                                       if (tracing) {
-                                               LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       }

                                        break;
                                }
                                p_response = &dynamic_response_info;
                                        break;
                                }
                                p_response = &dynamic_response_info;


@@ -1224,23 +1205,10 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                cmdsRecvd++;
 
                if (p_response != NULL) {
                cmdsRecvd++;
 
                if (p_response != NULL) {

-                       EmSendCmd14443aRaw(p_response->modulation, p_response->modulation_n, receivedCmd[0] == 0x52);
-                       // do the tracing for the previous reader request and this tag answer:
-                       uint8_t par[MAX_PARITY_SIZE];
-                       GetParity(p_response->response, p_response->response_n, par);
-                       EmLogTrace(Uart.output, 
-                                               Uart.len, 
-                                               Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                                               Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                                               Uart.parity,
-                                               p_response->response, 
-                                               p_response->response_n,
-                                               LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
-                                               (LastTimeProxToAirStart + p_response->ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
-                                               par);
-               }
-               
-               if (!tracing) {
+                       EmSendPrecompiledCmd(p_response);
+               }
+
+               if (!get_tracing()) {

                        Dbprintf("Trace Full. Simulation stopped.");
                        break;
                }
                        Dbprintf("Trace Full. Simulation stopped.");
                        break;
                }


@@ -1248,17 +1216,17 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
 
        Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
        LED_A_OFF();
 
        Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
        LED_A_OFF();

+       BigBuf_free_keep_EM();

 }
 
 
 // prepare a delayed transfer. This simply shifts ToSend[] by a number
 // of bits specified in the delay parameter.
 }
 
 
 // prepare a delayed transfer. This simply shifts ToSend[] by a number
 // of bits specified in the delay parameter.

-void PrepareDelayedTransfer(uint16_t delay)
-{
+static void PrepareDelayedTransfer(uint16_t delay) {

        uint8_t bitmask = 0;
        uint8_t bits_to_shift = 0;
        uint8_t bits_shifted = 0;
        uint8_t bitmask = 0;
        uint8_t bits_to_shift = 0;
        uint8_t bits_shifted = 0;

-       
+

        delay &= 0x07;
        if (delay) {
                for (uint16_t i = 0; i < delay; i++) {
        delay &= 0x07;
        if (delay) {
                for (uint16_t i = 0; i < delay; i++) {


@@ -1279,45 +1247,35 @@ void PrepareDelayedTransfer(uint16_t delay)
 // Transmit the command (to the tag) that was placed in ToSend[].
 // Parameter timing:
 // if NULL: transfer at next possible time, taking into account
 // Transmit the command (to the tag) that was placed in ToSend[].
 // Parameter timing:
 // if NULL: transfer at next possible time, taking into account

-//                     request guard time and frame delay time
-// if == 0:    transfer immediately and return time of transfer
+//          request guard time, startup frame guard time and frame delay time
+// if == 0: transfer immediately and return time of transfer

 // if != 0: delay transfer until time specified
 //-------------------------------------------------------------------------------------
 // if != 0: delay transfer until time specified
 //-------------------------------------------------------------------------------------

-static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing)
-{
-       
+static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing) {
+       LED_B_ON();
+       LED_D_ON();

        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
 
        uint32_t ThisTransferTime = 0;
 
        if (timing) {
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
 
        uint32_t ThisTransferTime = 0;
 
        if (timing) {

-               if(*timing == 0) {                                                                              // Measure time
+               if (*timing == 0) {                                      // Measure time

                        *timing = (GetCountSspClk() + 8) & 0xfffffff8;
                } else {
                        *timing = (GetCountSspClk() + 8) & 0xfffffff8;
                } else {

-                       PrepareDelayedTransfer(*timing & 0x00000007);           // Delay transfer (fine tuning - up to 7 MF clock ticks)
+                       PrepareDelayedTransfer(*timing & 0x00000007);       // Delay transfer (fine tuning - up to 7 MF clock ticks)

                }
                }

-               if(MF_DBGLEVEL >= 4 && GetCountSspClk() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
-               while(GetCountSspClk() < (*timing & 0xfffffff8));               // Delay transfer (multiple of 8 MF clock ticks)
+               if (MF_DBGLEVEL >= 4 && GetCountSspClk() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
+               while (GetCountSspClk() < (*timing & 0xfffffff8));      // Delay transfer (multiple of 8 MF clock ticks)

                LastTimeProxToAirStart = *timing;
        } else {
                ThisTransferTime = ((MAX(NextTransferTime, GetCountSspClk()) & 0xfffffff8) + 8);
                LastTimeProxToAirStart = *timing;
        } else {
                ThisTransferTime = ((MAX(NextTransferTime, GetCountSspClk()) & 0xfffffff8) + 8);

-               while(GetCountSspClk() < ThisTransferTime);
+               while (GetCountSspClk() < ThisTransferTime);

                LastTimeProxToAirStart = ThisTransferTime;
        }
                LastTimeProxToAirStart = ThisTransferTime;
        }

-       
-       // clear TXRDY
-       AT91C_BASE_SSC->SSC_THR = SEC_Y;
-
-       // for(uint16_t c = 0; c < 10;) {       // standard delay for each transfer (allow tag to be ready after last transmission)
-               // if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-                       // AT91C_BASE_SSC->SSC_THR = SEC_Y;     
-                       // c++;
-               // }
-       // }

 
        uint16_t c = 0;
 
        uint16_t c = 0;

-       for(;;) {
-               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+       for (;;) {
+               if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {

                        AT91C_BASE_SSC->SSC_THR = cmd[c];
                        c++;
                        if(c >= len) {
                        AT91C_BASE_SSC->SSC_THR = cmd[c];
                        c++;
                        if(c >= len) {


@@ -1325,17 +1283,16 @@ static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing
                        }
                }
        }
                        }
                }
        }

-       
+

        NextTransferTime = MAX(NextTransferTime, LastTimeProxToAirStart + REQUEST_GUARD_TIME);
        NextTransferTime = MAX(NextTransferTime, LastTimeProxToAirStart + REQUEST_GUARD_TIME);

-       
+       LED_B_OFF();

 }
 
 
 //-----------------------------------------------------------------------------
 // Prepare reader command (in bits, support short frames) to send to FPGA
 //-----------------------------------------------------------------------------
 }
 
 
 //-----------------------------------------------------------------------------
 // Prepare reader command (in bits, support short frames) to send to FPGA
 //-----------------------------------------------------------------------------

-void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8_t *parity)
-{
+static void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8_t *parity) {

        int i, j;
        int last;
        uint8_t b;
        int i, j;
        int last;
        uint8_t b;


@@ -1375,7 +1332,7 @@ void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8
                }
 
                // Only transmit parity bit if we transmitted a complete byte
                }
 
                // Only transmit parity bit if we transmitted a complete byte

-               if (j == 8) {
+               if (j == 8 && parity != NULL) {

                        // Get the parity bit
                        if (parity[i>>3] & (0x80 >> (i&0x0007))) {
                                // Sequence X
                        // Get the parity bit
                        if (parity[i>>3] & (0x80 >> (i&0x0007))) {
                                // Sequence X


@@ -1412,326 +1369,344 @@ void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8
        ToSendMax++;
 }
 
        ToSendMax++;
 }
 

-//-----------------------------------------------------------------------------
-// Prepare reader command to send to FPGA
-//-----------------------------------------------------------------------------
-void CodeIso14443aAsReaderPar(const uint8_t *cmd, uint16_t len, const uint8_t *parity)
-{
-  CodeIso14443aBitsAsReaderPar(cmd, len*8, parity);
-}

 
 //-----------------------------------------------------------------------------
 // Wait for commands from reader
 // Stop when button is pressed (return 1) or field was gone (return 2)
 // Or return 0 when command is captured
 //-----------------------------------------------------------------------------
 
 //-----------------------------------------------------------------------------
 // Wait for commands from reader
 // Stop when button is pressed (return 1) or field was gone (return 2)
 // Or return 0 when command is captured
 //-----------------------------------------------------------------------------

-static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity)
-{
+int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity) {
+       uint32_t field_off_time = -1;
+       uint32_t samples = 0;
+       int ret = 0;
+       uint8_t b = 0;;
+       uint8_t dmaBuf[DMA_BUFFER_SIZE];
+       uint8_t *upTo = dmaBuf;
+

        *len = 0;
 
        *len = 0;
 

-       uint32_t timer = 0, vtime = 0;
-       int analogCnt = 0;
-       int analogAVG = 0;
+       // Run a 'software UART' on the stream of incoming samples.
+       UartInit(received, parity);
+
+       // start ADC
+       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
+
+       // Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN
+       while (GetCountSspClk() < LastTimeProxToAirStart + LastProxToAirDuration + (FpgaSendQueueDelay>>3) - 8 - 3) /* wait */ ;

 
        // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
        // only, since we are receiving, not transmitting).
 
        // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
        // only, since we are receiving, not transmitting).

-       // Signal field is off with the appropriate LED
-       LED_D_OFF();

        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 

-       // Set ADC to read field strength
-       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
-       AT91C_BASE_ADC->ADC_MR =
-                               ADC_MODE_PRESCALE(32) |
-                               ADC_MODE_STARTUP_TIME(16) |
-                               ADC_MODE_SAMPLE_HOLD_TIME(8);
-       AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
-       // start ADC
-       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
-       
-       // Now run a 'software UART' on the stream of incoming samples.
-       UartInit(received, parity);
+       // clear receive register, measure time of next transfer
+       uint32_t temp = AT91C_BASE_SSC->SSC_RHR; (void) temp;
+       while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)) ;
+       uint32_t start_time = GetCountSspClk() & 0xfffffff8;

 
 

-       // Clear RXRDY:
-    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+       // Setup and start DMA.
+       FpgaSetupSscDma(dmaBuf, DMA_BUFFER_SIZE);

 
        for(;;) {
 
        for(;;) {

-               WDT_HIT();
+               uint16_t behindBy = ((uint8_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (DMA_BUFFER_SIZE-1);
+
+               if (behindBy == 0) continue;

 
 

-               if (BUTTON_PRESS()) return 1;
-
-               // test if the field exists
-               if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF)) {
-                       analogCnt++;
-                       analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
-                       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
-                       if (analogCnt >= 32) {
-                               if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
-                                       vtime = GetTickCount();
-                                       if (!timer) timer = vtime;
-                                       // 50ms no field --> card to idle state
-                                       if (vtime - timer > 50) return 2;
-                               } else
-                                       if (timer) timer = 0;
-                               analogCnt = 0;
-                               analogAVG = 0;
+               b = *upTo++;
+
+               if(upTo >= dmaBuf + DMA_BUFFER_SIZE) {                   // we have read all of the DMA buffer content.
+                       upTo = dmaBuf;                                       // start reading the circular buffer from the beginning
+                       if(behindBy > (9*DMA_BUFFER_SIZE/10)) {
+                               Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy);
+                               ret = 1;
+                               break;

                        }
                }
                        }
                }

+               if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_ENDRX)) {        // DMA Counter Register had reached 0, already rotated.
+                       AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;    // refresh the DMA Next Buffer and
+                       AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;      // DMA Next Counter registers
+               }

 
 

-               // receive and test the miller decoding
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-                       if(MillerDecoding(b, 0)) {
-                               *len = Uart.len;
-                               return 0;
+               if (BUTTON_PRESS()) {
+                       ret = 1;
+                       break;
+               }
+
+               // check reader's HF field
+               if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF_LOW)) {
+                       if ((MAX_ADC_HF_VOLTAGE_LOW * AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF_LOW]) >> 10 < MF_MINFIELDV) {
+                               if (GetTickCount() - field_off_time > 50) {
+                                       ret = 2; // reader has switched off HF field for more than 50ms. Timeout
+                                       break;
+                               }
+                       } else {
+                               field_off_time = GetTickCount(); // HF field is still there. Reset timer

                        }
                        }

-        }
+                       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; // restart ADC
+               }
+
+               if (MillerDecoding(b, start_time + samples*8)) {
+                       *len = Uart.len;
+                       EmLogTraceReader();
+                       ret = 0;
+                       break;
+               }

 
 

+               samples++;

        }
        }

+
+       FpgaDisableSscDma();
+       return ret;

 }
 
 
 }
 
 

-static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNeeded)
-{
+static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen) {
+       LED_C_ON();
+

        uint8_t b;
        uint16_t i = 0;
        uint8_t b;
        uint16_t i = 0;

-       uint32_t ThisTransferTime;
-       
+       bool correctionNeeded;
+

        // Modulate Manchester
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
 
        // include correction bit if necessary
        // Modulate Manchester
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
 
        // include correction bit if necessary

-       if (Uart.parityBits & 0x01) {
-               correctionNeeded = TRUE;
+       if (Uart.bitCount == 7)
+       {
+               // Short tags (7 bits) don't have parity, determine the correct value from MSB
+               correctionNeeded = Uart.output[0] & 0x40;

        }
        }

-       if(correctionNeeded) {
+       else
+       {
+               // Look at the last parity bit
+               correctionNeeded = Uart.parity[(Uart.len-1)/8] & (0x80 >> ((Uart.len-1) & 7));
+       }
+
+       if (correctionNeeded) {

                // 1236, so correction bit needed
                i = 0;
        } else {
                i = 1;
        }
 
                // 1236, so correction bit needed
                i = 0;
        } else {
                i = 1;
        }
 

-       // clear receiving shift register and holding register
-       while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+       // clear receiving shift register and holding register

        b = AT91C_BASE_SSC->SSC_RHR; (void) b;
        b = AT91C_BASE_SSC->SSC_RHR; (void) b;

-       while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+       while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));

        b = AT91C_BASE_SSC->SSC_RHR; (void) b;
        b = AT91C_BASE_SSC->SSC_RHR; (void) b;

-       
+

        // wait for the FPGA to signal fdt_indicator == 1 (the FPGA is ready to queue new data in its delay line)
        // wait for the FPGA to signal fdt_indicator == 1 (the FPGA is ready to queue new data in its delay line)

-       for (uint16_t j = 0; j < 5; j++) {      // allow timeout - better late than never
-               while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+       for (uint16_t j = 0; j < 5; j++) {  // allow timeout - better late than never
+               while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));

                if (AT91C_BASE_SSC->SSC_RHR) break;
        }
 
                if (AT91C_BASE_SSC->SSC_RHR) break;
        }
 

-       while ((ThisTransferTime = GetCountSspClk()) & 0x00000007);
-
-       // Clear TXRDY:
-       AT91C_BASE_SSC->SSC_THR = SEC_F;
+       LastTimeProxToAirStart = (GetCountSspClk() & 0xfffffff8) + (correctionNeeded?8:0);

 
        // send cycle
 
        // send cycle

-       for(; i <= respLen; ) {
+       for (; i < respLen; ) {

                if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
                        AT91C_BASE_SSC->SSC_THR = resp[i++];
                        FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
                }
                if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
                        AT91C_BASE_SSC->SSC_THR = resp[i++];
                        FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
                }

-       
+

                if(BUTTON_PRESS()) {
                        break;
                }
        }
 
                if(BUTTON_PRESS()) {
                        break;
                }
        }
 

-       // Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again:
-       for (i = 0; i < 2 ; ) {
-               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-                       AT91C_BASE_SSC->SSC_THR = SEC_F;
-                       FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-                       i++;
-               }
-       }
-       
-       LastTimeProxToAirStart = ThisTransferTime + (correctionNeeded?8:0);
-
+       LED_C_OFF();

        return 0;
 }
 
        return 0;
 }
 

-int EmSend4bitEx(uint8_t resp, bool correctionNeeded){
+
+int EmSend4bit(uint8_t resp){

        Code4bitAnswerAsTag(resp);
        Code4bitAnswerAsTag(resp);

-       int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
-       // do the tracing for the previous reader request and this tag answer:
-       uint8_t par[1];
-       GetParity(&resp, 1, par);
-       EmLogTrace(Uart.output, 
-                               Uart.len, 
-                               Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                               Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                               Uart.parity,
-                               &resp, 
-                               1, 
-                               LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
-                               (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
-                               par);
+       int res = EmSendCmd14443aRaw(ToSend, ToSendMax);
+       // Log this tag answer and fix timing of previous reader command:
+       EmLogTraceTag(&resp, 1, NULL, LastProxToAirDuration);

        return res;
 }
 
        return res;
 }
 

-int EmSend4bit(uint8_t resp){
-       return EmSend4bitEx(resp, false);
-}

 
 

-int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, bool correctionNeeded, uint8_t *par){
+static int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, uint8_t *par){

        CodeIso14443aAsTagPar(resp, respLen, par);
        CodeIso14443aAsTagPar(resp, respLen, par);

-       int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
-       // do the tracing for the previous reader request and this tag answer:
-       EmLogTrace(Uart.output, 
-                               Uart.len, 
-                               Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                               Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
-                               Uart.parity,
-                               resp, 
-                               respLen, 
-                               LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
-                               (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
-                               par);
+       int res = EmSendCmd14443aRaw(ToSend, ToSendMax);
+       // Log this tag answer and fix timing of previous reader command:
+       EmLogTraceTag(resp, respLen, par, LastProxToAirDuration);

        return res;
 }
 
        return res;
 }
 

-int EmSendCmdEx(uint8_t *resp, uint16_t respLen, bool correctionNeeded){
-       uint8_t par[MAX_PARITY_SIZE];
-       GetParity(resp, respLen, par);
-       return EmSendCmdExPar(resp, respLen, correctionNeeded, par);
-}

 
 int EmSendCmd(uint8_t *resp, uint16_t respLen){
        uint8_t par[MAX_PARITY_SIZE];
        GetParity(resp, respLen, par);
 
 int EmSendCmd(uint8_t *resp, uint16_t respLen){
        uint8_t par[MAX_PARITY_SIZE];
        GetParity(resp, respLen, par);

-       return EmSendCmdExPar(resp, respLen, false, par);
+       return EmSendCmdExPar(resp, respLen, par);

 }
 
 }
 

+

 int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par){
 int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par){

-       return EmSendCmdExPar(resp, respLen, false, par);
+       return EmSendCmdExPar(resp, respLen, par);

 }
 
 }
 

-bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint8_t *reader_Parity,
-                                uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_t *tag_Parity)
-{
-       if (tracing) {
-               // we cannot exactly measure the end and start of a received command from reader. However we know that the delay from
-               // end of the received command to start of the tag's (simulated by us) answer is n*128+20 or n*128+84 resp.
-               // with n >= 9. The start of the tags answer can be measured and therefore the end of the received command be calculated:
-               uint16_t reader_modlen = reader_EndTime - reader_StartTime;
-               uint16_t approx_fdt = tag_StartTime - reader_EndTime;
-               uint16_t exact_fdt = (approx_fdt - 20 + 32)/64 * 64 + 20;
-               reader_EndTime = tag_StartTime - exact_fdt;
-               reader_StartTime = reader_EndTime - reader_modlen;
-               if (!LogTrace(reader_data, reader_len, reader_StartTime, reader_EndTime, reader_Parity, TRUE)) {
-                       return FALSE;
-               } else return(!LogTrace(tag_data, tag_len, tag_StartTime, tag_EndTime, tag_Parity, FALSE));
-       } else {
-               return TRUE;
-       }
+
+int EmSendPrecompiledCmd(tag_response_info_t *response_info) {
+       int ret = EmSendCmd14443aRaw(response_info->modulation, response_info->modulation_n);
+       // Log this tag answer and fix timing of previous reader command:
+       EmLogTraceTag(response_info->response, response_info->response_n, &(response_info->par), response_info->ProxToAirDuration);
+       return ret;

 }
 
 }
 

+

 //-----------------------------------------------------------------------------
 // Wait a certain time for tag response
 //-----------------------------------------------------------------------------
 // Wait a certain time for tag response

-//  If a response is captured return TRUE
-//  If it takes too long return FALSE
+//  If a response is captured return true
+//  If it takes too long return false

 //-----------------------------------------------------------------------------
 //-----------------------------------------------------------------------------

-static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receivedResponsePar, uint16_t offset)
-{
+static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receivedResponsePar, uint16_t offset) {

        uint32_t c;
        uint32_t c;

-       
+

        // Set FPGA mode to "reader listen mode", no modulation (listen
        // only, since we are receiving, not transmitting).
        // Signal field is on with the appropriate LED
        LED_D_ON();
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
        // Set FPGA mode to "reader listen mode", no modulation (listen
        // only, since we are receiving, not transmitting).
        // Signal field is on with the appropriate LED
        LED_D_ON();
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);

-       
+

        // Now get the answer from the card
        DemodInit(receivedResponse, receivedResponsePar);
 
        // clear RXRDY:
        // Now get the answer from the card
        DemodInit(receivedResponse, receivedResponsePar);
 
        // clear RXRDY:

-    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-       
+       uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+

        c = 0;
        c = 0;

-       for(;;) {
+       for (;;) {

                WDT_HIT();
 
                WDT_HIT();
 

-               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+               if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {

                        b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
                        b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;

-                       if(ManchesterDecoding(b, offset, 0)) {
+                       if (ManchesterDecoding(b, offset, 0)) {

                                NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD);
                                NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD);

-                               return TRUE;
-                       } else if (c++ > iso14a_timeout) {
-                               return FALSE; 
+                               return true;
+                       } else if (c++ > iso14a_timeout && Demod.state == DEMOD_UNSYNCD) {
+                               return false;

                        }
                }
        }
 }
 
                        }
                }
        }
 }
 

-void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing)
-{
+
+void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing) {

 
        CodeIso14443aBitsAsReaderPar(frame, bits, par);
 
        CodeIso14443aBitsAsReaderPar(frame, bits, par);

-  
+

        // Send command to tag
        TransmitFor14443a(ToSend, ToSendMax, timing);
        // Send command to tag
        TransmitFor14443a(ToSend, ToSendMax, timing);

-       if(trigger)
+       if (trigger)

                LED_A_ON();
                LED_A_ON();

-  
+

        // Log reader command in trace buffer
        // Log reader command in trace buffer

-       if (tracing) {
-               LogTrace(frame, nbytes(bits), LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_READER, (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_READER, par, TRUE);
-       }
+       LogTrace(frame, nbytes(bits), LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_READER, (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_READER, par, true);

 }
 
 }
 

-void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing)
-{
-  ReaderTransmitBitsPar(frame, len*8, par, timing);
+
+void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing) {
+       ReaderTransmitBitsPar(frame, len*8, par, timing);

 }
 
 }
 

-void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing)
-{
+
+static void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) {

   // Generate parity and redirect
   uint8_t par[MAX_PARITY_SIZE];
   GetParity(frame, len/8, par);
   ReaderTransmitBitsPar(frame, len, par, timing);
 }
 
   // Generate parity and redirect
   uint8_t par[MAX_PARITY_SIZE];
   GetParity(frame, len/8, par);
   ReaderTransmitBitsPar(frame, len, par, timing);
 }
 

-void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing)
-{
+
+void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing) {

   // Generate parity and redirect
   uint8_t par[MAX_PARITY_SIZE];
   GetParity(frame, len, par);
   ReaderTransmitBitsPar(frame, len*8, par, timing);
 }
 
   // Generate parity and redirect
   uint8_t par[MAX_PARITY_SIZE];
   GetParity(frame, len, par);
   ReaderTransmitBitsPar(frame, len*8, par, timing);
 }
 

-int ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset, uint8_t *parity)
-{
-       if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, offset)) return FALSE;
-       if (tracing) {
-               LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
-       }
+
+static int ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset, uint8_t *parity) {
+       if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, offset)) return false;
+       LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, false);

        return Demod.len;
 }
 
        return Demod.len;
 }
 

-int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity)
-{
-       if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, 0)) return FALSE;
-       if (tracing) {
-               LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
-       }
+
+int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) {
+       if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, 0)) return false;
+
+       LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, false);

        return Demod.len;
 }
 
        return Demod.len;
 }
 

-/* performs iso14443a anticollision procedure
- * fills the uid pointer unless NULL
- * fills resp_data unless NULL */
-int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr) {
-       uint8_t wupa[]       = { 0x52 };  // 0x26 - REQA  0x52 - WAKE-UP
+
+static void iso14a_set_ATS_times(uint8_t *ats) {
+
+       uint8_t tb1;
+       uint8_t fwi, sfgi;
+       uint32_t fwt, sfgt;
+
+       if (ats[0] > 1) {                           // there is a format byte T0
+               if ((ats[1] & 0x20) == 0x20) {          // there is an interface byte TB(1)
+                       if ((ats[1] & 0x10) == 0x10) {      // there is an interface byte TA(1) preceding TB(1)
+                               tb1 = ats[3];
+                       } else {
+                               tb1 = ats[2];
+                       }
+                       fwi = (tb1 & 0xf0) >> 4;            // frame waiting time integer (FWI)
+                       if (fwi != 15) {
+                               fwt = 256 * 16 * (1 << fwi);    // frame waiting time (FWT) in 1/fc
+                               iso14a_set_timeout(fwt/(8*16));
+                       }
+                       sfgi = tb1 & 0x0f;                  // startup frame guard time integer (SFGI)
+                       if (sfgi != 0 && sfgi != 15) {
+                               sfgt = 256 * 16 * (1 << sfgi);  // startup frame guard time (SFGT) in 1/fc
+                               NextTransferTime = MAX(NextTransferTime, Demod.endTime + (sfgt - DELAY_AIR2ARM_AS_READER - DELAY_ARM2AIR_AS_READER)/16);
+                       }
+               }
+       }
+}
+
+
+static int GetATQA(uint8_t *resp, uint8_t *resp_par) {
+
+#define WUPA_RETRY_TIMEOUT  10  // 10ms
+       uint8_t wupa[]       = {ISO14443A_CMD_WUPA};  // 0x26 - REQA  0x52 - WAKE-UP
+
+       uint32_t save_iso14a_timeout = iso14a_get_timeout();
+       iso14a_set_timeout(1236/(16*8)+1);      // response to WUPA is expected at exactly 1236/fc. No need to wait longer.
+
+       uint32_t start_time = GetTickCount();
+       int len;
+
+       // we may need several tries if we did send an unknown command or a wrong authentication before...
+       do {
+               // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+               ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
+               // Receive the ATQA
+               len = ReaderReceive(resp, resp_par);
+       } while (len == 0 && GetTickCount() <= start_time + WUPA_RETRY_TIMEOUT);
+
+       iso14a_set_timeout(save_iso14a_timeout);
+       return len;
+}
+
+
+// performs iso14443a anticollision (optional) and card select procedure
+// fills the uid and cuid pointer unless NULL
+// fills the card info record unless NULL
+// if anticollision is false, then the UID must be provided in uid_ptr[]
+// and num_cascades must be set (1: 4 Byte UID, 2: 7 Byte UID, 3: 10 Byte UID)
+// requests ATS unless no_rats is true
+int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades, bool no_rats) {

        uint8_t sel_all[]    = { 0x93,0x20 };
        uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
        uint8_t rats[]       = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
        uint8_t sel_all[]    = { 0x93,0x20 };
        uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
        uint8_t rats[]       = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0

-       uint8_t *resp = ((uint8_t *)BigBuf) + RECV_RESP_OFFSET;
-       uint8_t *resp_par = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET;
+       uint8_t resp[MAX_FRAME_SIZE]; // theoretically. A usual RATS will be much smaller
+       uint8_t resp_par[MAX_PARITY_SIZE];

        byte_t uid_resp[4];
        size_t uid_resp_len;
 
        byte_t uid_resp[4];
        size_t uid_resp_len;
 


@@ -1739,68 +1714,89 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
        int cascade_level = 0;
        int len;
 
        int cascade_level = 0;
        int len;
 

-       // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
-    ReaderTransmitBitsPar(wupa,7,0, NULL);
-       
-       // Receive the ATQA
-       if(!ReaderReceive(resp, resp_par)) return 0;
-       //Dbprintf("atqa: %02x %02x",resp[1],resp[0]);
+       // init card struct
+       if (p_hi14a_card) {
+               p_hi14a_card->uidlen = 0;
+               memset(p_hi14a_card->uid, 0, 10);
+               p_hi14a_card->ats_len = 0;
+       }

 
 

-       if(p_hi14a_card) {
+       if (!GetATQA(resp, resp_par)) {
+               return 0;
+       }
+
+       if (p_hi14a_card) {

                memcpy(p_hi14a_card->atqa, resp, 2);
                memcpy(p_hi14a_card->atqa, resp, 2);

-               p_hi14a_card->uidlen = 0;
-               memset(p_hi14a_card->uid,0,10);

        }
 
        }
 

-       // clear uid
-       if (uid_ptr) {
-               memset(uid_ptr,0,10);
+       if (anticollision) {
+               // clear uid
+               if (uid_ptr) {
+                       memset(uid_ptr,0,10);
+               }
+       }
+
+       // check for proprietary anticollision:
+       if ((resp[0] & 0x1F) == 0) {
+               return 3;

        }
 
        // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
        // which case we need to make a cascade 2 request and select - this is a long UID
        }
 
        // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
        // which case we need to make a cascade 2 request and select - this is a long UID

-       // While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
-       for(; sak & 0x04; cascade_level++) {
+       // While the UID is not complete, the 3rd bit (from the right) is set in the SAK.
+       for (; sak & 0x04; cascade_level++) {

                // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
                sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
 
                // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
                sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
 

-               // SELECT_ALL
-               ReaderTransmit(sel_all, sizeof(sel_all), NULL);
-               if (!ReaderReceive(resp, resp_par)) return 0;
-
-               if (Demod.collisionPos) {                       // we had a collision and need to construct the UID bit by bit
-                       memset(uid_resp, 0, 4);
-                       uint16_t uid_resp_bits = 0;
-                       uint16_t collision_answer_offset = 0;
-                       // anti-collision-loop:
-                       while (Demod.collisionPos) {
-                               Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos);
-                               for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) {      // add valid UID bits before collision point
-                                       uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01;
-                                       uid_resp[uid_resp_bits & 0xf8] |= UIDbit << (uid_resp_bits % 8);
+               if (anticollision) {
+                       // SELECT_ALL
+                       ReaderTransmit(sel_all, sizeof(sel_all), NULL);
+                       if (!ReaderReceive(resp, resp_par)) {
+                               return 0;
+                       }
+
+                       if (Demod.collisionPos) {           // we had a collision and need to construct the UID bit by bit
+                               memset(uid_resp, 0, 4);
+                               uint16_t uid_resp_bits = 0;
+                               uint16_t collision_answer_offset = 0;
+                               // anti-collision-loop:
+                               while (Demod.collisionPos) {
+                                       Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos);
+                                       for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) {  // add valid UID bits before collision point
+                                               uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01;
+                                               uid_resp[uid_resp_bits / 8] |= UIDbit << (uid_resp_bits % 8);
+                                       }
+                                       uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8);                  // next time select the card(s) with a 1 in the collision position
+                                       uid_resp_bits++;
+                                       // construct anticollosion command:
+                                       sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07);     // length of data in bytes and bits
+                                       for (uint16_t i = 0; i <= uid_resp_bits/8; i++) {
+                                               sel_uid[2+i] = uid_resp[i];
+                                       }
+                                       collision_answer_offset = uid_resp_bits%8;
+                                       ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL);
+                                       if (!ReaderReceiveOffset(resp, collision_answer_offset, resp_par)) {
+                                               return 0;
+                                       }

                                }
                                }

-                               uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8);                                  // next time select the card(s) with a 1 in the collision position
-                               uid_resp_bits++;
-                               // construct anticollosion command:
-                               sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07);     // length of data in bytes and bits
-                               for (uint16_t i = 0; i <= uid_resp_bits/8; i++) {
-                                       sel_uid[2+i] = uid_resp[i];
+                               // finally, add the last bits and BCC of the UID
+                               for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) {
+                                       uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01;
+                                       uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8);

                                }
                                }

-                               collision_answer_offset = uid_resp_bits%8;
-                               ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL);
-                               if (!ReaderReceiveOffset(resp, collision_answer_offset, resp_par)) return 0;
+
+                       } else {        // no collision, use the response to SELECT_ALL as current uid
+                               memcpy(uid_resp, resp, 4);

                        }
                        }

-                       // finally, add the last bits and BCC of the UID
-                       for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) {
-                               uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01;
-                               uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8);
+               } else {
+                       if (cascade_level < num_cascades - 1) {
+                               uid_resp[0] = 0x88;
+                               memcpy(uid_resp+1, uid_ptr+cascade_level*3, 3);
+                       } else {
+                               memcpy(uid_resp, uid_ptr+cascade_level*3, 4);

                        }
                        }

-
-               } else {                // no collision, use the response to SELECT_ALL as current uid
-                       memcpy(uid_resp, resp, 4);

                }
                uid_resp_len = 4;
                }
                uid_resp_len = 4;

-               //Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);

 
                // calculate crypto UID. Always use last 4 Bytes.
                if(cuid_ptr) {
 
                // calculate crypto UID. Always use last 4 Bytes.
                if(cuid_ptr) {


@@ -1808,33 +1804,29 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
                }
 
                // Construct SELECT UID command
                }
 
                // Construct SELECT UID command

-               sel_uid[1] = 0x70;                                                                                                      // transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC)
-               memcpy(sel_uid+2, uid_resp, 4);                                                                         // the UID
-               sel_uid[6] = sel_uid[2] ^ sel_uid[3] ^ sel_uid[4] ^ sel_uid[5];         // calculate and add BCC
-               AppendCrc14443a(sel_uid, 7);                                                                            // calculate and add CRC
+               sel_uid[1] = 0x70;                                                  // transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC)
+               memcpy(sel_uid+2, uid_resp, 4);                                     // the UID received during anticollision, or the provided UID
+               sel_uid[6] = sel_uid[2] ^ sel_uid[3] ^ sel_uid[4] ^ sel_uid[5];     // calculate and add BCC
+               AppendCrc14443a(sel_uid, 7);                                        // calculate and add CRC

                ReaderTransmit(sel_uid, sizeof(sel_uid), NULL);
 
                // Receive the SAK
                ReaderTransmit(sel_uid, sizeof(sel_uid), NULL);
 
                // Receive the SAK

-               if (!ReaderReceive(resp, resp_par)) return 0;
+               if (!ReaderReceive(resp, resp_par)) {
+                       return 0;
+               }

                sak = resp[0];
 
                sak = resp[0];
 

-               // Test if more parts of the uid are comming
+               // Test if more parts of the uid are coming

                if ((sak & 0x04) /* && uid_resp[0] == 0x88 */) {
                        // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
                        // http://www.nxp.com/documents/application_note/AN10927.pdf
                if ((sak & 0x04) /* && uid_resp[0] == 0x88 */) {
                        // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
                        // http://www.nxp.com/documents/application_note/AN10927.pdf

-                       // This was earlier:
-                       //memcpy(uid_resp, uid_resp + 1, 3);
-                       // But memcpy should not be used for overlapping arrays, 
-                       // and memmove appears to not be available in the arm build. 
-                       // Therefore:

                        uid_resp[0] = uid_resp[1];
                        uid_resp[1] = uid_resp[2];
                        uid_resp[0] = uid_resp[1];
                        uid_resp[1] = uid_resp[2];

-                       uid_resp[2] = uid_resp[3]; 
-
+                       uid_resp[2] = uid_resp[3];

                        uid_resp_len = 3;
                }
 
                        uid_resp_len = 3;
                }
 

-               if(uid_ptr) {
+               if(uid_ptr && anticollision) {

                        memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
                }
 
                        memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
                }
 


@@ -1846,34 +1838,40 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 
        if(p_hi14a_card) {
                p_hi14a_card->sak = sak;
 
        if(p_hi14a_card) {
                p_hi14a_card->sak = sak;

-               p_hi14a_card->ats_len = 0;

        }
 
        }
 

-       if( (sak & 0x20) == 0) {
-               return 2; // non iso14443a compliant tag
-       }
+       // PICC compilant with iso14443a-4 ---> (SAK & 0x20 != 0)
+       if( (sak & 0x20) == 0) return 2;

 
 

-       // Request for answer to select
-       AppendCrc14443a(rats, 2);
-       ReaderTransmit(rats, sizeof(rats), NULL);
+       if (!no_rats) {
+               // Request for answer to select
+               AppendCrc14443a(rats, 2);
+               ReaderTransmit(rats, sizeof(rats), NULL);

 
 

-       if (!(len = ReaderReceive(resp, resp_par))) return 0;
+               if (!(len = ReaderReceive(resp, resp_par))) {
+                       return 0;
+               }

 
 

-       if(p_hi14a_card) {
-               memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
-               p_hi14a_card->ats_len = len;
-       }
+               if(p_hi14a_card) {
+                       memcpy(p_hi14a_card->ats, resp, len);
+                       p_hi14a_card->ats_len = len;
+               }
+
+               // reset the PCB block number
+               iso14_pcb_blocknum = 0;
+
+               // set default timeout and delay next transfer based on ATS
+               iso14a_set_ATS_times(resp);

 
 

-       // reset the PCB block number
-       iso14_pcb_blocknum = 0;
-       
-       return 1;       
+       }
+       return 1;

 }
 
 }
 

+

 void iso14443a_setup(uint8_t fpga_minor_mode) {
        FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
        // Set up the synchronous serial port
 void iso14443a_setup(uint8_t fpga_minor_mode) {
        FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
        // Set up the synchronous serial port

-       FpgaSetupSsc();
+       FpgaSetupSsc(FPGA_MAJOR_MODE_HF_ISO14443A);

        // connect Demodulated Signal to ADC:
        SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
        // connect Demodulated Signal to ADC:
        SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 


@@ -1886,103 +1884,233 @@ void iso14443a_setup(uint8_t fpga_minor_mode) {
        }
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode);
 
        }
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode);
 

+       // Set ADC to read field strength
+       AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
+       AT91C_BASE_ADC->ADC_MR =
+                               ADC_MODE_PRESCALE(63) |
+                               ADC_MODE_STARTUP_TIME(1) |
+                               ADC_MODE_SAMPLE_HOLD_TIME(15);
+       AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF_LOW);
+

        // Start the timer
        StartCountSspClk();
        // Start the timer
        StartCountSspClk();

-       
+

        DemodReset();
        UartReset();
        DemodReset();
        UartReset();

+       LastTimeProxToAirStart = 0;
+       FpgaSendQueueDelay = 0;
+       LastProxToAirDuration = 20; // arbitrary small value. Avoid lock in EmGetCmd()

        NextTransferTime = 2*DELAY_ARM2AIR_AS_READER;
        NextTransferTime = 2*DELAY_ARM2AIR_AS_READER;

-       iso14a_set_timeout(1050); // 10ms default
+       iso14a_set_timeout(1060); // 10ms default

 }
 
 }
 

-int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) {
+/* Peter Fillmore 2015
+Added card id field to the function
+ info from ISO14443A standard
+b1 = Block Number
+b2 = RFU (always 1)
+b3 = depends on block
+b4 = Card ID following if set to 1
+b5 = depends on block type
+b6 = depends on block type
+b7,b8 = block type.
+Coding of I-BLOCK:
+b8 b7 b6 b5 b4 b3 b2 b1
+0  0  0  x  x  x  1  x
+b5 = chaining bit
+Coding of R-block:
+b8 b7 b6 b5 b4 b3 b2 b1
+1  0  1  x  x  0  1  x
+b5 = ACK/NACK
+Coding of S-block:
+b8 b7 b6 b5 b4 b3 b2 b1
+1  1  x  x  x  0  1  0
+b5,b6 = 00 - DESELECT
+               11 - WTX
+*/
+int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, bool send_chaining, void *data, uint8_t *res) {

        uint8_t parity[MAX_PARITY_SIZE];
        uint8_t parity[MAX_PARITY_SIZE];

-       uint8_t real_cmd[cmd_len+4];
-       real_cmd[0] = 0x0a; //I-Block
-       // put block number into the PCB
-       real_cmd[0] |= iso14_pcb_blocknum;
-       real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
-       memcpy(real_cmd+2, cmd, cmd_len);
-       AppendCrc14443a(real_cmd,cmd_len+2);
- 
-       ReaderTransmit(real_cmd, cmd_len+4, NULL);
+       uint8_t real_cmd[cmd_len + 4];
+
+       if (cmd_len) {
+               // ISO 14443 APDU frame: PCB [CID] [NAD] APDU CRC PCB=0x02
+               real_cmd[0] = 0x02; // bnr,nad,cid,chn=0; i-block(0x00)
+               if (send_chaining) {
+                       real_cmd[0] |= 0x10;
+               }
+               // put block number into the PCB
+               real_cmd[0] |= iso14_pcb_blocknum;
+               memcpy(real_cmd + 1, cmd, cmd_len);
+       } else {
+               // R-block. ACK
+               real_cmd[0] = 0xA2; // r-block + ACK
+               real_cmd[0] |= iso14_pcb_blocknum;
+       }
+       AppendCrc14443a(real_cmd, cmd_len + 1);
+
+       ReaderTransmit(real_cmd, cmd_len + 3, NULL);
+

        size_t len = ReaderReceive(data, parity);
        uint8_t *data_bytes = (uint8_t *) data;
        size_t len = ReaderReceive(data, parity);
        uint8_t *data_bytes = (uint8_t *) data;

-       if (!len)
+
+       if (!len) {

                return 0; //DATA LINK ERROR
                return 0; //DATA LINK ERROR

-       // if we received an I- or R(ACK)-Block with a block number equal to the
-       // current block number, toggle the current block number
-       else if (len >= 4 // PCB+CID+CRC = 4 bytes
-                && ((data_bytes[0] & 0xC0) == 0 // I-Block
-                    || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
-                && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
-       {
-               iso14_pcb_blocknum ^= 1;
+       } else {
+               // S-Block WTX
+               while (len && ((data_bytes[0] & 0xF2) == 0xF2)) {
+                       uint32_t save_iso14a_timeout = iso14a_get_timeout();
+                       // temporarily increase timeout
+                       iso14a_set_timeout(MAX((data_bytes[1] & 0x3f) * save_iso14a_timeout, MAX_ISO14A_TIMEOUT));
+                       // Transmit WTX back
+                       // byte1 - WTXM [1..59]. command FWT=FWT*WTXM
+                       data_bytes[1] = data_bytes[1] & 0x3f; // 2 high bits mandatory set to 0b
+                       // now need to fix CRC.
+                       AppendCrc14443a(data_bytes, len - 2);
+                       // transmit S-Block
+                       ReaderTransmit(data_bytes, len, NULL);
+                       // retrieve the result again (with increased timeout)
+                       len = ReaderReceive(data, parity);
+                       data_bytes = data;
+                       // restore timeout
+                       iso14a_set_timeout(save_iso14a_timeout);
+               }
+
+               // if we received an I- or R(ACK)-Block with a block number equal to the
+               // current block number, toggle the current block number
+               if (len >= 3 // PCB+CRC = 3 bytes
+                        && ((data_bytes[0] & 0xC0) == 0 // I-Block
+                                || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
+                        && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
+               {
+                       iso14_pcb_blocknum ^= 1;
+               }
+
+               // if we received I-block with chaining we need to send ACK and receive another block of data
+               if (res)
+                       *res = data_bytes[0];
+
+               // crc check
+               if (len >= 3 && !CheckCrc14443(CRC_14443_A, data_bytes, len)) {
+                       return -1;
+               }
+
+       }
+
+       if (len) {
+               // cut frame byte
+               len -= 1;
+               // memmove(data_bytes, data_bytes + 1, len);
+               for (int i = 0; i < len; i++)
+                       data_bytes[i] = data_bytes[i + 1];

        }
 
        return len;
 }
 
        }
 
        return len;
 }
 

+

 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
 //
 //-----------------------------------------------------------------------------
 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
 //
 //-----------------------------------------------------------------------------

-void ReaderIso14443a(UsbCommand *c)
-{
+void ReaderIso14443a(UsbCommand *c) {
+

        iso14a_command_t param = c->arg[0];
        uint8_t *cmd = c->d.asBytes;
        iso14a_command_t param = c->arg[0];
        uint8_t *cmd = c->d.asBytes;

-       size_t len = c->arg[1];
-       size_t lenbits = c->arg[2];
+       size_t len = c->arg[1] & 0xffff;
+       size_t lenbits = c->arg[1] >> 16;
+       uint32_t timeout = c->arg[2];

        uint32_t arg0 = 0;
        uint32_t arg0 = 0;

-       byte_t buf[USB_CMD_DATA_SIZE];
+       byte_t buf[USB_CMD_DATA_SIZE] = {0};

        uint8_t par[MAX_PARITY_SIZE];
        uint8_t par[MAX_PARITY_SIZE];

-  
-       if(param & ISO14A_CONNECT) {
-               iso14a_clear_trace();
-       }
+       bool cantSELECT = false;

 
 

-       iso14a_set_tracing(TRUE);
+       set_tracing(true);
+
+       if(param & ISO14A_CLEAR_TRACE) {
+               clear_trace();
+       }

 
        if(param & ISO14A_REQUEST_TRIGGER) {
 
        if(param & ISO14A_REQUEST_TRIGGER) {

-               iso14a_set_trigger(TRUE);
+               iso14a_set_trigger(true);

        }
 
        if(param & ISO14A_CONNECT) {
        }
 
        if(param & ISO14A_CONNECT) {

+               LED_A_ON();

                iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN);
                if(!(param & ISO14A_NO_SELECT)) {
                        iso14a_card_select_t *card = (iso14a_card_select_t*)buf;
                iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN);
                if(!(param & ISO14A_NO_SELECT)) {
                        iso14a_card_select_t *card = (iso14a_card_select_t*)buf;

-                       arg0 = iso14443a_select_card(NULL,card,NULL);
+                       arg0 = iso14443a_select_card(NULL, card, NULL, true, 0, param & ISO14A_NO_RATS);
+
+                       // if we cant select then we cant send data
+                       if (arg0 != 1 && arg0 != 2) {
+                               // 1 - all is OK with ATS, 2 - without ATS
+                               cantSELECT = true;
+                       }
+                       FpgaDisableTracing();
+                       LED_B_ON();

                        cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t));
                        cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t));

+                       LED_B_OFF();

                }
        }
 
        if(param & ISO14A_SET_TIMEOUT) {
                }
        }
 
        if(param & ISO14A_SET_TIMEOUT) {

-               iso14a_timeout = c->arg[2];
+               iso14a_set_timeout(timeout);

        }
 
        }
 

-       if(param & ISO14A_APDU) {
-               arg0 = iso14_apdu(cmd, len, buf);
-               cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
+       if(param & ISO14A_APDU && !cantSELECT) {
+               uint8_t res;
+               arg0 = iso14_apdu(cmd, len, (param & ISO14A_SEND_CHAINING), buf, &res);
+               FpgaDisableTracing();
+               LED_B_ON();
+               cmd_send(CMD_ACK, arg0, res, 0, buf, sizeof(buf));
+               LED_B_OFF();

        }
 
        }
 

-       if(param & ISO14A_RAW) {
+       if(param & ISO14A_RAW && !cantSELECT) {

                if(param & ISO14A_APPEND_CRC) {
                if(param & ISO14A_APPEND_CRC) {

-                       AppendCrc14443a(cmd,len);
+                       if(param & ISO14A_TOPAZMODE) {
+                               AppendCrc14443b(cmd,len);
+                       } else {
+                               AppendCrc14443a(cmd,len);
+                       }

                        len += 2;
                        if (lenbits) lenbits += 16;
                }
                        len += 2;
                        if (lenbits) lenbits += 16;
                }

-               if(lenbits>0) {
-                       GetParity(cmd, lenbits/8, par);
-                       ReaderTransmitBitsPar(cmd, lenbits, par, NULL);
-               } else {
-                       ReaderTransmit(cmd,len, NULL);
+               if(lenbits>0) {             // want to send a specific number of bits (e.g. short commands)
+                       if(param & ISO14A_TOPAZMODE) {
+                               int bits_to_send = lenbits;
+                               uint16_t i = 0;
+                               ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 7), NULL, NULL);     // first byte is always short (7bits) and no parity
+                               bits_to_send -= 7;
+                               while (bits_to_send > 0) {
+                                       ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 8), NULL, NULL); // following bytes are 8 bit and no parity
+                                       bits_to_send -= 8;
+                               }
+                       } else {
+                               GetParity(cmd, lenbits/8, par);
+                               ReaderTransmitBitsPar(cmd, lenbits, par, NULL);                         // bytes are 8 bit with odd parity
+                       }
+               } else {                    // want to send complete bytes only
+                       if(param & ISO14A_TOPAZMODE) {
+                               uint16_t i = 0;
+                               ReaderTransmitBitsPar(&cmd[i++], 7, NULL, NULL);                        // first byte: 7 bits, no paritiy
+                               while (i < len) {
+                                       ReaderTransmitBitsPar(&cmd[i++], 8, NULL, NULL);                    // following bytes: 8 bits, no paritiy
+                               }
+                       } else {
+                               ReaderTransmit(cmd,len, NULL);                                          // 8 bits, odd parity
+                       }

                }
                arg0 = ReaderReceive(buf, par);
                }
                arg0 = ReaderReceive(buf, par);

+               FpgaDisableTracing();
+
+               LED_B_ON();

                cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
                cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));

+               LED_B_OFF();

        }
 
        if(param & ISO14A_REQUEST_TRIGGER) {
        }
 
        if(param & ISO14A_REQUEST_TRIGGER) {

-               iso14a_set_trigger(FALSE);
+               iso14a_set_trigger(false);

        }
 
        if(param & ISO14A_NO_DISCONNECT) {
        }
 
        if(param & ISO14A_NO_DISCONNECT) {


@@ -1997,7 +2125,7 @@ void ReaderIso14443a(UsbCommand *c)
 // Determine the distance between two nonces.
 // Assume that the difference is small, but we don't know which is first.
 // Therefore try in alternating directions.
 // Determine the distance between two nonces.
 // Assume that the difference is small, but we don't know which is first.
 // Therefore try in alternating directions.

-int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
+static int32_t dist_nt(uint32_t nt1, uint32_t nt2) {

 
        uint16_t i;
        uint32_t nttmp1, nttmp2;
 
        uint16_t i;
        uint32_t nttmp1, nttmp2;


@@ -2006,14 +2134,14 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 
        nttmp1 = nt1;
        nttmp2 = nt2;
 
        nttmp1 = nt1;
        nttmp2 = nt2;

-       
+

        for (i = 1; i < 32768; i++) {
                nttmp1 = prng_successor(nttmp1, 1);
                if (nttmp1 == nt2) return i;
                nttmp2 = prng_successor(nttmp2, 1);
        for (i = 1; i < 32768; i++) {
                nttmp1 = prng_successor(nttmp1, 1);
                if (nttmp1 == nt2) return i;
                nttmp2 = prng_successor(nttmp2, 1);

-                       if (nttmp2 == nt1) return -i;
+               if (nttmp2 == nt1) return -i;

                }
                }

-       
+

        return(-99999); // either nt1 or nt2 are invalid nonces
 }
 
        return(-99999); // either nt1 or nt2 are invalid nonces
 }
 


@@ -2031,42 +2159,44 @@ void ReaderMifare(bool first_try)
        uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
        static uint8_t mf_nr_ar3;
 
        uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
        static uint8_t mf_nr_ar3;
 

-       uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + RECV_RESP_OFFSET);
-       uint8_t* receivedAnswerPar = (((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET);
+       uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
+       uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
+
+       iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+
+       // free eventually allocated BigBuf memory. We want all for tracing.
+       BigBuf_free();

 
 

-       iso14a_clear_trace();
-       iso14a_set_tracing(TRUE);
+       clear_trace();
+       set_tracing(true);

 
 

-       byte_t nt_diff = 0;
-       uint8_t par[1] = {0};   // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
-       static byte_t par_low = 0;
-       bool led_on = TRUE;
+       uint8_t nt_diff = 0;
+       uint8_t par[1] = {0};   // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
+       static uint8_t par_low = 0;
+       bool led_on = true;

        uint8_t uid[10]  ={0};
        uint32_t cuid;
 
        uint32_t nt = 0;
        uint32_t previous_nt = 0;
        static uint32_t nt_attacked = 0;
        uint8_t uid[10]  ={0};
        uint32_t cuid;
 
        uint32_t nt = 0;
        uint32_t previous_nt = 0;
        static uint32_t nt_attacked = 0;

-       byte_t par_list[8] = {0,0,0,0,0,0,0,0};
-       byte_t ks_list[8] = {0,0,0,0,0,0,0,0};
+       uint8_t par_list[8] = {0x00};
+       uint8_t ks_list[8] = {0x00};

 
 

-       static uint32_t sync_time;
-       static uint32_t sync_cycles;
+       #define PRNG_SEQUENCE_LENGTH  (1 << 16);
+       uint32_t sync_time = GetCountSspClk() & 0xfffffff8;
+       static int32_t sync_cycles;

        int catch_up_cycles = 0;
        int last_catch_up = 0;
        int catch_up_cycles = 0;
        int last_catch_up = 0;

+       uint16_t elapsed_prng_sequences;

        uint16_t consecutive_resyncs = 0;
        int isOK = 0;
 
        uint16_t consecutive_resyncs = 0;
        int isOK = 0;
 

-
-
-       if (first_try) { 
+       if (first_try) {

                mf_nr_ar3 = 0;
                mf_nr_ar3 = 0;

-               iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
-               sync_time = GetCountSspClk() & 0xfffffff8;
-               sync_cycles = 65536;                                                                    // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
+               par[0] = par_low = 0;
+               sync_cycles = PRNG_SEQUENCE_LENGTH;                         // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the tag nonces).

                nt_attacked = 0;
                nt_attacked = 0;

-               nt = 0;
-               par[0] = 0;

        }
        else {
                // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
        }
        else {
                // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)


@@ -2078,38 +2208,90 @@ void ReaderMifare(bool first_try)
        LED_A_ON();
        LED_B_OFF();
        LED_C_OFF();
        LED_A_ON();
        LED_B_OFF();
        LED_C_OFF();

-       
-  
-       for(uint16_t i = 0; TRUE; i++) {
-               
+
+
+       #define MAX_UNEXPECTED_RANDOM   4       // maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up.
+       #define MAX_SYNC_TRIES          32
+       #define SYNC_TIME_BUFFER        16      // if there is only SYNC_TIME_BUFFER left before next planned sync, wait for next PRNG cycle
+       #define NUM_DEBUG_INFOS         8       // per strategy
+       #define MAX_STRATEGY            3
+       uint16_t unexpected_random = 0;
+       uint16_t sync_tries = 0;
+       int16_t debug_info_nr = -1;
+       uint16_t strategy = 0;
+       int32_t debug_info[MAX_STRATEGY][NUM_DEBUG_INFOS];
+       uint32_t select_time;
+       uint32_t halt_time;
+
+       for (uint16_t i = 0; true; i++) {
+
+               LED_C_ON();

                WDT_HIT();
 
                // Test if the action was cancelled
                if(BUTTON_PRESS()) {
                WDT_HIT();
 
                // Test if the action was cancelled
                if(BUTTON_PRESS()) {

+                       isOK = -1;

                        break;
                }
                        break;
                }

-               
-               LED_C_ON();

 
 

-               if(!iso14443a_select_card(uid, NULL, &cuid)) {
-                       if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Can't select card");
-                       continue;
+               if (strategy == 2) {
+                       // test with additional hlt command
+                       halt_time = 0;
+                       int len = mifare_sendcmd_short(NULL, false, 0x50, 0x00, receivedAnswer, receivedAnswerPar, &halt_time);
+                       if (len && MF_DBGLEVEL >= 3) {
+                               Dbprintf("Unexpected response of %d bytes to hlt command (additional debugging).", len);
+                       }

                }
 
                }
 

-               sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
-               catch_up_cycles = 0;
+               if (strategy == 3) {
+                       // test with FPGA power off/on
+                       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+                       SpinDelay(200);
+                       iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+                       SpinDelay(100);
+               }

 
 

-               // if we missed the sync time already, advance to the next nonce repeat
-               while(GetCountSspClk() > sync_time) {
-                       sync_time = (sync_time & 0xfffffff8) + sync_cycles;
+               if(!iso14443a_select_card(uid, NULL, &cuid, true, 0, true)) {
+                       if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Can't select card");
+                       continue;

                }
                }

+               select_time = GetCountSspClk();

 
 

-               // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) 
-               ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+               elapsed_prng_sequences = 1;
+               if (debug_info_nr == -1) {
+                       sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
+                       catch_up_cycles = 0;
+
+                       // if we missed the sync time already or are about to miss it, advance to the next nonce repeat
+                       while(sync_time < GetCountSspClk() + SYNC_TIME_BUFFER) {
+                               elapsed_prng_sequences++;
+                               sync_time = (sync_time & 0xfffffff8) + sync_cycles;
+                       }
+
+                       // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
+                       ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+               } else {
+                       // collect some information on tag nonces for debugging:
+                       #define DEBUG_FIXED_SYNC_CYCLES PRNG_SEQUENCE_LENGTH
+                       if (strategy == 0) {
+                               // nonce distances at fixed time after card select:
+                               sync_time = select_time + DEBUG_FIXED_SYNC_CYCLES;
+                       } else if (strategy == 1) {
+                               // nonce distances at fixed time between authentications:
+                               sync_time = sync_time + DEBUG_FIXED_SYNC_CYCLES;
+                       } else if (strategy == 2) {
+                               // nonce distances at fixed time after halt:
+                               sync_time = halt_time + DEBUG_FIXED_SYNC_CYCLES;
+                       } else {
+                               // nonce_distances at fixed time after power on
+                               sync_time = DEBUG_FIXED_SYNC_CYCLES;
+                       }
+                       ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+               }

 
                // Receive the (4 Byte) "random" nonce
                if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {
 
                // Receive the (4 Byte) "random" nonce
                if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {

-                       if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Couldn't receive tag nonce");
+                       if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Couldn't receive tag nonce");

                        continue;
                  }
 
                        continue;
                  }
 


@@ -2123,49 +2305,75 @@ void ReaderMifare(bool first_try)
                        int nt_distance = dist_nt(previous_nt, nt);
                        if (nt_distance == 0) {
                                nt_attacked = nt;
                        int nt_distance = dist_nt(previous_nt, nt);
                        if (nt_distance == 0) {
                                nt_attacked = nt;

-                       }
-                       else {
-                               if (nt_distance == -99999) { // invalid nonce received, try again
-                                       continue;
+                       } else {
+                               if (nt_distance == -99999) { // invalid nonce received
+                                       unexpected_random++;
+                                       if (unexpected_random > MAX_UNEXPECTED_RANDOM) {
+                                               isOK = -3;      // Card has an unpredictable PRNG. Give up
+                                               break;
+                                       } else {
+                                               continue;       // continue trying...
+                                       }
+                               }
+                               if (++sync_tries > MAX_SYNC_TRIES) {
+                                       if (strategy > MAX_STRATEGY || MF_DBGLEVEL < 3) {
+                                               isOK = -4;          // Card's PRNG runs at an unexpected frequency or resets unexpectedly
+                                               break;
+                                       } else {                // continue for a while, just to collect some debug info
+                                               debug_info[strategy][debug_info_nr] = nt_distance;
+                                               debug_info_nr++;
+                                               if (debug_info_nr == NUM_DEBUG_INFOS) {
+                                                       strategy++;
+                                                       debug_info_nr = 0;
+                                               }
+                                               continue;
+                                       }
+                               }
+                               sync_cycles = (sync_cycles - nt_distance/elapsed_prng_sequences);
+                               if (sync_cycles <= 0) {
+                                       sync_cycles += PRNG_SEQUENCE_LENGTH;
+                               }
+                               if (MF_DBGLEVEL >= 3) {
+                                       Dbprintf("calibrating in cycle %d. nt_distance=%d, elapsed_prng_sequences=%d, new sync_cycles: %d\n", i, nt_distance, elapsed_prng_sequences, sync_cycles);

                                }
                                }

-                               sync_cycles = (sync_cycles - nt_distance);
-                               if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);

                                continue;
                        }
                }
 
                                continue;
                        }
                }
 

-               if ((nt != nt_attacked) && nt_attacked) {       // we somehow lost sync. Try to catch up again...
+               if ((nt != nt_attacked) && nt_attacked) {   // we somehow lost sync. Try to catch up again...

                        catch_up_cycles = -dist_nt(nt_attacked, nt);
                        catch_up_cycles = -dist_nt(nt_attacked, nt);

-                       if (catch_up_cycles == 99999) {                 // invalid nonce received. Don't resync on that one.
+                       if (catch_up_cycles == 99999) {         // invalid nonce received. Don't resync on that one.

                                catch_up_cycles = 0;
                                continue;
                        }
                                catch_up_cycles = 0;
                                continue;
                        }

+                       catch_up_cycles /= elapsed_prng_sequences;

                        if (catch_up_cycles == last_catch_up) {
                                consecutive_resyncs++;
                        }
                        else {
                                last_catch_up = catch_up_cycles;
                        if (catch_up_cycles == last_catch_up) {
                                consecutive_resyncs++;
                        }
                        else {
                                last_catch_up = catch_up_cycles;

-                           consecutive_resyncs = 0;
+                               consecutive_resyncs = 0;

                        }
                        if (consecutive_resyncs < 3) {
                                if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, -catch_up_cycles, consecutive_resyncs);
                        }
                        }
                        if (consecutive_resyncs < 3) {
                                if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, -catch_up_cycles, consecutive_resyncs);
                        }

-                       else {  
+                       else {

                                sync_cycles = sync_cycles + catch_up_cycles;
                                if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles);
                                sync_cycles = sync_cycles + catch_up_cycles;
                                if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles);

+                               last_catch_up = 0;
+                               catch_up_cycles = 0;
+                               consecutive_resyncs = 0;

                        }
                        continue;
                }
                        }
                        continue;
                }

- 
+

                consecutive_resyncs = 0;
                consecutive_resyncs = 0;

-               
+

                // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
                // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding

-               if (ReaderReceive(receivedAnswer, receivedAnswerPar))
-               {
-                       catch_up_cycles = 8;    // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
-       
-                       if (nt_diff == 0)
-                       {
+               if (ReaderReceive(receivedAnswer, receivedAnswerPar)) {
+                       catch_up_cycles = 8;    // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
+
+                       if (nt_diff == 0) {

                                par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change
                        }
 
                                par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change
                        }
 


@@ -2188,6 +2396,10 @@ void ReaderMifare(bool first_try)
                        if (nt_diff == 0 && first_try)
                        {
                                par[0]++;
                        if (nt_diff == 0 && first_try)
                        {
                                par[0]++;

+                               if (par[0] == 0x00) {       // tried all 256 possible parities without success. Card doesn't send NACK.
+                                       isOK = -2;
+                                       break;
+                               }

                        } else {
                                par[0] = ((par[0] & 0x1F) + 1) | par_low;
                        }
                        } else {
                                par[0] = ((par[0] & 0x1F) + 1) | par_low;
                        }


@@ -2196,530 +2408,39 @@ void ReaderMifare(bool first_try)
 
 
        mf_nr_ar[3] &= 0x1F;
 
 
        mf_nr_ar[3] &= 0x1F;

-       
-       byte_t buf[28];
-       memcpy(buf + 0,  uid, 4);
-       num_to_bytes(nt, 4, buf + 4);
-       memcpy(buf + 8,  par_list, 8);
-       memcpy(buf + 16, ks_list, 8);
-       memcpy(buf + 24, mf_nr_ar, 4);
-               
-       cmd_send(CMD_ACK,isOK,0,0,buf,28);
-
-       // Thats it...
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       LEDsoff();
-
-       iso14a_set_tracing(FALSE);
-}
-
-/**
-  *MIFARE 1K simulate.
-  *
-  *@param flags :
-  *    FLAG_INTERACTIVE - In interactive mode, we are expected to finish the operation with an ACK
-  * 4B_FLAG_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that
-  * 7B_FLAG_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that
-  *    FLAG_NR_AR_ATTACK  - means we should collect NR_AR responses for bruteforcing later
-  *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is inifite
-  */
-void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain)
-{
-       int cardSTATE = MFEMUL_NOFIELD;
-       int _7BUID = 0;
-       int vHf = 0;    // in mV
-       int res;
-       uint32_t selTimer = 0;
-       uint32_t authTimer = 0;
-       uint16_t len = 0;
-       uint8_t cardWRBL = 0;
-       uint8_t cardAUTHSC = 0;
-       uint8_t cardAUTHKEY = 0xff;  // no authentication
-       uint32_t cardRr = 0;
-       uint32_t cuid = 0;
-       //uint32_t rn_enc = 0;
-       uint32_t ans = 0;
-       uint32_t cardINTREG = 0;
-       uint8_t cardINTBLOCK = 0;
-       struct Crypto1State mpcs = {0, 0};
-       struct Crypto1State *pcs;
-       pcs = &mpcs;
-       uint32_t numReads = 0;//Counts numer of times reader read a block
-       uint8_t* receivedCmd = get_bigbufptr_recvcmdbuf();
-       uint8_t* receivedCmd_par = receivedCmd + MAX_FRAME_SIZE;
-       uint8_t* response = get_bigbufptr_recvrespbuf();
-       uint8_t* response_par = response + MAX_FRAME_SIZE;
-       
-       uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
-       uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
-       uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
-       uint8_t rSAK[] = {0x08, 0xb6, 0xdd};
-       uint8_t rSAK1[] = {0x04, 0xda, 0x17};
-
-       uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
-       uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
-               
-       //Here, we collect UID,NT,AR,NR,UID2,NT2,AR2,NR2
-       // This can be used in a reader-only attack.
-       // (it can also be retrieved via 'hf 14a list', but hey...
-       uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0};
-       uint8_t ar_nr_collected = 0;
-
-       // clear trace
-    iso14a_clear_trace();
-       iso14a_set_tracing(TRUE);
-
-       // Authenticate response - nonce
-       uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
-       
-       //-- Determine the UID
-       // Can be set from emulator memory, incoming data
-       // and can be 7 or 4 bytes long
-       if (flags & FLAG_4B_UID_IN_DATA)
-       {
-               // 4B uid comes from data-portion of packet
-               memcpy(rUIDBCC1,datain,4);
-               rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
-
-       } else if (flags & FLAG_7B_UID_IN_DATA) {
-               // 7B uid comes from data-portion of packet
-               memcpy(&rUIDBCC1[1],datain,3);
-               memcpy(rUIDBCC2, datain+3, 4);
-               _7BUID = true;
-       } else {
-               // get UID from emul memory
-               emlGetMemBt(receivedCmd, 7, 1);
-               _7BUID = !(receivedCmd[0] == 0x00);
-               if (!_7BUID) {                     // ---------- 4BUID
-                       emlGetMemBt(rUIDBCC1, 0, 4);
-               } else {                           // ---------- 7BUID
-                       emlGetMemBt(&rUIDBCC1[1], 0, 3);
-                       emlGetMemBt(rUIDBCC2, 3, 4);
-               }
-       }
-
-       /*
-        * Regardless of what method was used to set the UID, set fifth byte and modify
-        * the ATQA for 4 or 7-byte UID
-        */
-       rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
-       if (_7BUID) {
-               rATQA[0] = 0x44;
-               rUIDBCC1[0] = 0x88;
-               rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
-       }
-
-       // We need to listen to the high-frequency, peak-detected path.
-       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-

 
 

-       if (MF_DBGLEVEL >= 1)   {
-               if (!_7BUID) {
-                       Dbprintf("4B UID: %02x%02x%02x%02x", 
-                               rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3]);
-               } else {
-                       Dbprintf("7B UID: (%02x)%02x%02x%02x%02x%02x%02x%02x",
-                               rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3],
-                               rUIDBCC2[0], rUIDBCC2[1] ,rUIDBCC2[2], rUIDBCC2[3]);
-               }
-       }
-
-       bool finished = FALSE;
-       while (!BUTTON_PRESS() && !finished) {
-               WDT_HIT();
-
-               // find reader field
-               // Vref = 3300mV, and an 10:1 voltage divider on the input
-               // can measure voltages up to 33000 mV
-               if (cardSTATE == MFEMUL_NOFIELD) {
-                       vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
-                       if (vHf > MF_MINFIELDV) {
-                               cardSTATE_TO_IDLE();
-                               LED_A_ON();
-                       }
-               } 
-               if(cardSTATE == MFEMUL_NOFIELD) continue;
-
-               //Now, get data
-
-               res = EmGetCmd(receivedCmd, &len, receivedCmd_par);
-               if (res == 2) { //Field is off!
-                       cardSTATE = MFEMUL_NOFIELD;
-                       LEDsoff();
-                       continue;
-               } else if (res == 1) {
-                       break;  //return value 1 means button press
-               }
-                       
-               // REQ or WUP request in ANY state and WUP in HALTED state
-               if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) {
-                       selTimer = GetTickCount();
-                       EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52));
-                       cardSTATE = MFEMUL_SELECT1;
-
-                       // init crypto block
-                       LED_B_OFF();
-                       LED_C_OFF();
-                       crypto1_destroy(pcs);
-                       cardAUTHKEY = 0xff;
-                       continue;
-               }
-               
-               switch (cardSTATE) {
-                       case MFEMUL_NOFIELD:
-                       case MFEMUL_HALTED:
-                       case MFEMUL_IDLE:{
-                               LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                               break;
-                       }
-                       case MFEMUL_SELECT1:{
-                               // select all
-                               if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) {
-                                       if (MF_DBGLEVEL >= 4)   Dbprintf("SELECT ALL received");
-                                       EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1));
-                                       break;
+       if (isOK == -4) {
+               if (MF_DBGLEVEL >= 3) {
+                       for (uint16_t i = 0; i <= MAX_STRATEGY; i++) {
+                               for (uint16_t j = 0; j < NUM_DEBUG_INFOS; j++) {
+                                       Dbprintf("collected debug info[%d][%d] = %d", i, j, debug_info[i][j]);

                                }
                                }

-
-                               if (MF_DBGLEVEL >= 4 && len == 9 && receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 )
-                               {
-                                       Dbprintf("SELECT %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]);
-                               }
-                               // select card
-                               if (len == 9 && 
-                                               (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
-                                       EmSendCmd(_7BUID?rSAK1:rSAK, _7BUID?sizeof(rSAK1):sizeof(rSAK));
-                                       cuid = bytes_to_num(rUIDBCC1, 4);
-                                       if (!_7BUID) {
-                                               cardSTATE = MFEMUL_WORK;
-                                               LED_B_ON();
-                                               if (MF_DBGLEVEL >= 4)   Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
-                                               break;
-                                       } else {
-                                               cardSTATE = MFEMUL_SELECT2;
-                                       }
-                               }
-                               break;

                        }
                        }

-                       case MFEMUL_AUTH1:{
-                               if( len != 8)
-                               {
-                                       cardSTATE_TO_IDLE();
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-                               uint32_t ar = bytes_to_num(receivedCmd, 4);
-                               uint32_t nr = bytes_to_num(&receivedCmd[4], 4);
-
-                               //Collect AR/NR
-                               if(ar_nr_collected < 2){
-                                       if(ar_nr_responses[2] != ar)
-                                       {// Avoid duplicates... probably not necessary, ar should vary. 
-                                               ar_nr_responses[ar_nr_collected*4] = cuid;
-                                               ar_nr_responses[ar_nr_collected*4+1] = nonce;
-                                               ar_nr_responses[ar_nr_collected*4+2] = ar;
-                                               ar_nr_responses[ar_nr_collected*4+3] = nr;
-                                               ar_nr_collected++;
-                                       }
-                               }
-
-                               // --- crypto
-                               crypto1_word(pcs, ar , 1);
-                               cardRr = nr ^ crypto1_word(pcs, 0, 0);
-
-                               // test if auth OK
-                               if (cardRr != prng_successor(nonce, 64)){
-                                       if (MF_DBGLEVEL >= 2) Dbprintf("AUTH FAILED for sector %d with key %c. cardRr=%08x, succ=%08x",
-                                                       cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
-                                                       cardRr, prng_successor(nonce, 64));
-                                       // Shouldn't we respond anything here?
-                                       // Right now, we don't nack or anything, which causes the
-                                       // reader to do a WUPA after a while. /Martin
-                                       // -- which is the correct response. /piwi
-                                       cardSTATE_TO_IDLE();
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-
-                               ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
-
-                               num_to_bytes(ans, 4, rAUTH_AT);
-                               // --- crypto
-                               EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
-                               LED_C_ON();
-                               cardSTATE = MFEMUL_WORK;
-                               if (MF_DBGLEVEL >= 4)   Dbprintf("AUTH COMPLETED for sector %d with key %c. time=%d", 
-                                       cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
-                                       GetTickCount() - authTimer);
-                               break;
-                       }
-                       case MFEMUL_SELECT2:{
-                               if (!len) { 
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-                               if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
-                                       EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
-                                       break;
-                               }
-
-                               // select 2 card
-                               if (len == 9 && 
-                                               (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) {
-                                       EmSendCmd(rSAK, sizeof(rSAK));
-                                       cuid = bytes_to_num(rUIDBCC2, 4);
-                                       cardSTATE = MFEMUL_WORK;
-                                       LED_B_ON();
-                                       if (MF_DBGLEVEL >= 4)   Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
-                                       break;
-                               }
-                               
-                               // i guess there is a command). go into the work state.
-                               if (len != 4) {
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-                               cardSTATE = MFEMUL_WORK;
-                               //goto lbWORK;
-                               //intentional fall-through to the next case-stmt
-                       }
-
-                       case MFEMUL_WORK:{
-                               if (len == 0) {
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-                               
-                               bool encrypted_data = (cardAUTHKEY != 0xFF) ;
+               }
+       }

 
 

-                               if(encrypted_data) {
-                                       // decrypt seqence
-                                       mf_crypto1_decrypt(pcs, receivedCmd, len);
-                               }
-                               
-                               if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
-                                       authTimer = GetTickCount();
-                                       cardAUTHSC = receivedCmd[1] / 4;  // received block num
-                                       cardAUTHKEY = receivedCmd[0] - 0x60;
-                                       crypto1_destroy(pcs);//Added by martin
-                                       crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
-
-                                       if (!encrypted_data) { // first authentication
-                                               if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY  );
-
-                                               crypto1_word(pcs, cuid ^ nonce, 0);//Update crypto state
-                                               num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce
-                                       } else { // nested authentication
-                                               if (MF_DBGLEVEL >= 4) Dbprintf("Reader doing nested authentication for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY );
-                                               ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); 
-                                               num_to_bytes(ans, 4, rAUTH_AT);
-                                       }
-                                       EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
-                                       //Dbprintf("Sending rAUTH %02x%02x%02x%02x", rAUTH_AT[0],rAUTH_AT[1],rAUTH_AT[2],rAUTH_AT[3]);
-                                       cardSTATE = MFEMUL_AUTH1;
-                                       break;
-                               }
-                               
-                               // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued
-                               // BUT... ACK --> NACK
-                               if (len == 1 && receivedCmd[0] == CARD_ACK) {
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       break;
-                               }
-                               
-                               // rule 12 of 7.5.3. in ISO 14443-4. R(NAK) --> R(ACK)
-                               if (len == 1 && receivedCmd[0] == CARD_NACK_NA) {
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-                                       break;
-                               }
-                               
-                               if(len != 4) {
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
+       FpgaDisableTracing();

 
 

-                               if(receivedCmd[0] == 0x30 // read block
-                                               || receivedCmd[0] == 0xA0 // write block
-                                               || receivedCmd[0] == 0xC0 // inc
-                                               || receivedCmd[0] == 0xC1 // dec
-                                               || receivedCmd[0] == 0xC2 // restore
-                                               || receivedCmd[0] == 0xB0) { // transfer
-                                       if (receivedCmd[1] >= 16 * 4) {
-                                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
-                                               break;
-                                       }
+       uint8_t buf[32];
+       memcpy(buf + 0,  uid, 4);
+       num_to_bytes(nt, 4, buf + 4);
+       memcpy(buf + 8,  par_list, 8);
+       memcpy(buf + 16, ks_list, 8);
+       memcpy(buf + 24, mf_nr_ar, 8);

 
 

-                                       if (receivedCmd[1] / 4 != cardAUTHSC) {
-                                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC);
-                                               break;
-                                       }
-                               }
-                               // read block
-                               if (receivedCmd[0] == 0x30) {
-                                       if (MF_DBGLEVEL >= 4) {
-                                               Dbprintf("Reader reading block %d (0x%02x)",receivedCmd[1],receivedCmd[1]);
-                                       }
-                                       emlGetMem(response, receivedCmd[1], 1);
-                                       AppendCrc14443a(response, 16);
-                                       mf_crypto1_encrypt(pcs, response, 18, response_par);
-                                       EmSendCmdPar(response, 18, response_par);
-                                       numReads++;
-                                       if(exitAfterNReads > 0 && numReads == exitAfterNReads) {
-                                               Dbprintf("%d reads done, exiting", numReads);
-                                               finished = true;
-                                       }
-                                       break;
-                               }
-                               // write block
-                               if (receivedCmd[0] == 0xA0) {
-                                       if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0xA0 write block %d (%02x)",receivedCmd[1],receivedCmd[1]);
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-                                       cardSTATE = MFEMUL_WRITEBL2;
-                                       cardWRBL = receivedCmd[1];
-                                       break;
-                               }
-                               // increment, decrement, restore
-                               if (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2) {
-                                       if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x inc(0xC1)/dec(0xC0)/restore(0xC2) block %d (%02x)",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
-                                       if (emlCheckValBl(receivedCmd[1])) {
-                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate on block, but emlCheckValBl failed, nacking");
-                                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                               break;
-                                       }
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-                                       if (receivedCmd[0] == 0xC1)
-                                               cardSTATE = MFEMUL_INTREG_INC;
-                                       if (receivedCmd[0] == 0xC0)
-                                               cardSTATE = MFEMUL_INTREG_DEC;
-                                       if (receivedCmd[0] == 0xC2)
-                                               cardSTATE = MFEMUL_INTREG_REST;
-                                       cardWRBL = receivedCmd[1];
-                                       break;
-                               }
-                               // transfer
-                               if (receivedCmd[0] == 0xB0) {
-                                       if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x transfer block %d (%02x)",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
-                                       if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1]))
-                                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       else
-                                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-                                       break;
-                               }
-                               // halt
-                               if (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00) {
-                                       LED_B_OFF();
-                                       LED_C_OFF();
-                                       cardSTATE = MFEMUL_HALTED;
-                                       if (MF_DBGLEVEL >= 4)   Dbprintf("--> HALTED. Selected time: %d ms",  GetTickCount() - selTimer);
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                                       break;
-                               }
-                               // RATS
-                               if (receivedCmd[0] == 0xe0) {//RATS
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       break;
-                               }
-                               // command not allowed
-                               if (MF_DBGLEVEL >= 4)   Dbprintf("Received command not allowed, nacking");
-                               EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                               break;
-                       }
-                       case MFEMUL_WRITEBL2:{
-                               if (len == 18){
-                                       mf_crypto1_decrypt(pcs, receivedCmd, len);
-                                       emlSetMem(receivedCmd, cardWRBL, 1);
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-                                       cardSTATE = MFEMUL_WORK;
-                               } else {
-                                       cardSTATE_TO_IDLE();
-                                       LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                               }
-                               break;
-                       }
-                       
-                       case MFEMUL_INTREG_INC:{
-                               mf_crypto1_decrypt(pcs, receivedCmd, len);
-                               memcpy(&ans, receivedCmd, 4);
-                               if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       cardSTATE_TO_IDLE();
-                                       break;
-                               } 
-                               LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                               cardINTREG = cardINTREG + ans;
-                               cardSTATE = MFEMUL_WORK;
-                               break;
-                       }
-                       case MFEMUL_INTREG_DEC:{
-                               mf_crypto1_decrypt(pcs, receivedCmd, len);
-                               memcpy(&ans, receivedCmd, 4);
-                               if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       cardSTATE_TO_IDLE();
-                                       break;
-                               }
-                               LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                               cardINTREG = cardINTREG - ans;
-                               cardSTATE = MFEMUL_WORK;
-                               break;
-                       }
-                       case MFEMUL_INTREG_REST:{
-                               mf_crypto1_decrypt(pcs, receivedCmd, len);
-                               memcpy(&ans, receivedCmd, 4);
-                               if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
-                                       EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                       cardSTATE_TO_IDLE();
-                                       break;
-                               }
-                               LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
-                               cardSTATE = MFEMUL_WORK;
-                               break;
-                       }
-               }
-       }
+       cmd_send(CMD_ACK, isOK, 0, 0, buf, 32);

 
 

+       // Thats it...

        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        LEDsoff();
 
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
        LEDsoff();
 

-       if(flags & FLAG_INTERACTIVE)// Interactive mode flag, means we need to send ACK
-       {
-               //May just aswell send the collected ar_nr in the response aswell
-               cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_responses,ar_nr_collected*4*4);
-       }
-
-       if(flags & FLAG_NR_AR_ATTACK)
-       {
-               if(ar_nr_collected > 1) {
-                       Dbprintf("Collected two pairs of AR/NR which can be used to extract keys from reader:");
-                       Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
-                                        ar_nr_responses[0], // UID
-                                       ar_nr_responses[1], //NT
-                                       ar_nr_responses[2], //AR1
-                                       ar_nr_responses[3], //NR1
-                                       ar_nr_responses[6], //AR2
-                                       ar_nr_responses[7] //NR2
-                                       );
-               } else {
-                       Dbprintf("Failed to obtain two AR/NR pairs!");
-                       if(ar_nr_collected >0) {
-                               Dbprintf("Only got these: UID=%08x, nonce=%08x, AR1=%08x, NR1=%08x",
-                                               ar_nr_responses[0], // UID
-                                               ar_nr_responses[1], //NT
-                                               ar_nr_responses[2], //AR1
-                                               ar_nr_responses[3] //NR1
-                                               );
-                       }
-               }
-       }
-       if (MF_DBGLEVEL >= 1)   Dbprintf("Emulator stopped. Tracing: %d  trace length: %d ",    tracing, traceLen);
+       set_tracing(false);

 }
 
 
 }
 
 

-

 //-----------------------------------------------------------------------------
 //-----------------------------------------------------------------------------

-// MIFARE sniffer. 
-// 
+// MIFARE sniffer.
+//

 //-----------------------------------------------------------------------------
 void RAMFUNC SniffMifare(uint8_t param) {
        // param:
 //-----------------------------------------------------------------------------
 void RAMFUNC SniffMifare(uint8_t param) {
        // param:


@@ -2728,33 +2449,33 @@ void RAMFUNC SniffMifare(uint8_t param) {
 
        // C(red) A(yellow) B(green)
        LEDsoff();
 
        // C(red) A(yellow) B(green)
        LEDsoff();

+       LED_A_ON();
+

        // init trace buffer
        // init trace buffer

-       iso14a_clear_trace();
-       iso14a_set_tracing(TRUE);
+       clear_trace();
+       set_tracing(true);

 
        // The command (reader -> tag) that we're receiving.
        // The length of a received command will in most cases be no more than 18 bytes.
        // So 32 should be enough!
 
        // The command (reader -> tag) that we're receiving.
        // The length of a received command will in most cases be no more than 18 bytes.
        // So 32 should be enough!

-       uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
-       uint8_t *receivedCmdPar = ((uint8_t *)BigBuf) + RECV_CMD_PAR_OFFSET;
+       uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE];
+       uint8_t receivedCmdPar[MAX_MIFARE_PARITY_SIZE];

        // The response (tag -> reader) that we're receiving.
        // The response (tag -> reader) that we're receiving.

-       uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RESP_OFFSET);
-       uint8_t *receivedResponsePar = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET;
+       uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE];
+       uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE];

 
 

-       // As we receive stuff, we copy it from receivedCmd or receivedResponse
-       // into trace, along with its length and other annotations.
-       //uint8_t *trace = (uint8_t *)BigBuf;
-       
-       // The DMA buffer, used to stream samples from the FPGA
-       uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET;
+       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+       // free eventually allocated BigBuf memory
+       BigBuf_free();
+       // allocate the DMA buffer, used to stream samples from the FPGA
+       uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);

        uint8_t *data = dmaBuf;
        uint8_t previous_data = 0;
        int maxDataLen = 0;
        int dataLen = 0;
        uint8_t *data = dmaBuf;
        uint8_t previous_data = 0;
        int maxDataLen = 0;
        int dataLen = 0;

-       bool ReaderIsActive = FALSE;
-       bool TagIsActive = FALSE;
-
-       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+       bool ReaderIsActive = false;
+       bool TagIsActive = false;

 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);
 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);


@@ -2765,47 +2486,44 @@ void RAMFUNC SniffMifare(uint8_t param) {
        // Setup for the DMA.
        FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer.
 
        // Setup for the DMA.
        FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer.
 

-       LED_D_OFF();
-       

        // init sniffer
        MfSniffInit();
 
        // And now we loop, receiving samples.
        // init sniffer
        MfSniffInit();
 
        // And now we loop, receiving samples.

-       for(uint32_t sniffCounter = 0; TRUE; ) {
-       
+       for (uint32_t sniffCounter = 0; true; ) {
+

                if(BUTTON_PRESS()) {
                if(BUTTON_PRESS()) {

-                       DbpString("cancelled by button");
+                       DbpString("Canceled by button.");

                        break;
                }
 
                        break;
                }
 

-               LED_A_ON();

                WDT_HIT();
                WDT_HIT();

-               
-               if ((sniffCounter & 0x0000FFFF) == 0) { // from time to time
+
+               if ((sniffCounter & 0x0000FFFF) == 0) { // from time to time

                        // check if a transaction is completed (timeout after 2000ms).
                        // if yes, stop the DMA transfer and send what we have so far to the client
                        // check if a transaction is completed (timeout after 2000ms).
                        // if yes, stop the DMA transfer and send what we have so far to the client

-                       if (MfSniffSend(2000)) {                        
+                       if (MfSniffSend(2000)) {

                                // Reset everything - we missed some sniffed data anyway while the DMA was stopped
                                sniffCounter = 0;
                                data = dmaBuf;
                                maxDataLen = 0;
                                // Reset everything - we missed some sniffed data anyway while the DMA was stopped
                                sniffCounter = 0;
                                data = dmaBuf;
                                maxDataLen = 0;

-                               ReaderIsActive = FALSE;
-                               TagIsActive = FALSE;
+                               ReaderIsActive = false;
+                               TagIsActive = false;

                                FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer.
                        }
                }
                                FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer.
                        }
                }

-               
-               int register readBufDataP = data - dmaBuf;      // number of bytes we have processed so far
+
+               int register readBufDataP = data - dmaBuf;  // number of bytes we have processed so far

                int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; // number of bytes already transferred
                int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; // number of bytes already transferred

-               if (readBufDataP <= dmaBufDataP){                       // we are processing the same block of data which is currently being transferred
-                       dataLen = dmaBufDataP - readBufDataP;   // number of bytes still to be processed
-               } else {                                                                        
+               if (readBufDataP <= dmaBufDataP){           // we are processing the same block of data which is currently being transferred
+                       dataLen = dmaBufDataP - readBufDataP;   // number of bytes still to be processed
+               } else {

                        dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP; // number of bytes still to be processed
                }
                // test for length of buffer
                        dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP; // number of bytes still to be processed
                }
                // test for length of buffer

-               if(dataLen > maxDataLen) {                                      // we are more behind than ever...
-                       maxDataLen = dataLen;                                   
-                       if(dataLen > 400) {
+               if(dataLen > maxDataLen) {                  // we are more behind than ever...
+                       maxDataLen = dataLen;
+                       if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {

                                Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
                                break;
                        }
                                Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
                                break;
                        }


@@ -2824,34 +2542,33 @@ void RAMFUNC SniffMifare(uint8_t param) {
                        AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
                }
 
                        AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
                }
 

-               LED_A_OFF();
-               

                if (sniffCounter & 0x01) {
 
                if (sniffCounter & 0x01) {
 

-                       if(!TagIsActive) {              // no need to try decoding tag data if the reader is sending
+                       if(!TagIsActive) {      // no need to try decoding tag data if the reader is sending

                                uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
                                if(MillerDecoding(readerdata, (sniffCounter-1)*4)) {
                                uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
                                if(MillerDecoding(readerdata, (sniffCounter-1)*4)) {

-                                       LED_C_INV();
-                                       if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break;
+
+                                       if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, true)) break;

 
                                        /* And ready to receive another command. */
 
                                        /* And ready to receive another command. */

-                                       UartReset();
-                                       
+                                       UartInit(receivedCmd, receivedCmdPar);
+

                                        /* And also reset the demod code */
                                        DemodReset();
                                }
                                ReaderIsActive = (Uart.state != STATE_UNSYNCD);
                        }
                                        /* And also reset the demod code */
                                        DemodReset();
                                }
                                ReaderIsActive = (Uart.state != STATE_UNSYNCD);
                        }

-                       
-                       if(!ReaderIsActive) {           // no need to try decoding tag data if the reader is sending
+
+                       if(!ReaderIsActive) {       // no need to try decoding tag data if the reader is sending

                                uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
                                if(ManchesterDecoding(tagdata, 0, (sniffCounter-1)*4)) {
                                uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
                                if(ManchesterDecoding(tagdata, 0, (sniffCounter-1)*4)) {

-                                       LED_C_INV();

 
 

-                                       if (MfSniffLogic(receivedResponse, Demod.len, Demod.parity, Demod.bitCount, FALSE)) break;
+                                       if (MfSniffLogic(receivedResponse, Demod.len, Demod.parity, Demod.bitCount, false)) break;

 
                                        // And ready to receive another response.
                                        DemodReset();
 
                                        // And ready to receive another response.
                                        DemodReset();

+                                       // And reset the Miller decoder including its (now outdated) input buffer
+                                       UartInit(receivedCmd, receivedCmdPar);

                                }
                                TagIsActive = (Demod.state != DEMOD_UNSYNCD);
                        }
                                }
                                TagIsActive = (Demod.state != DEMOD_UNSYNCD);
                        }


@@ -2866,11 +2583,13 @@ void RAMFUNC SniffMifare(uint8_t param) {
 
        } // main cycle
 
 
        } // main cycle
 

-       DbpString("COMMAND FINISHED");
-
+       FpgaDisableTracing();

        FpgaDisableSscDma();
        FpgaDisableSscDma();

+       LEDsoff();
+
+       DbpString("COMMAND FINISHED.");
+

        MfSniffEnd();
        MfSniffEnd();

-       
+

        Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len);
        Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len);

-       LEDsoff();

 }
 }