Merge branch 'master' of https://github.com/Proxmark/proxmark3

[proxmark3-svn] / armsrc / iso14443.c

diff --git a/armsrc/iso14443.c b/armsrc/iso14443.c
index 4d7d4fa8f2ee8ccd0f32339a60f708f5bd177aee..d570bf2d000c6cc97e37f8dc9464f9fa0e09cad3 100644 (file)
--- a/armsrc/iso14443.c
+++ b/armsrc/iso14443.c
@@ -10,20 +10,20 @@
 // supported.
 //-----------------------------------------------------------------------------
 
 // supported.
 //-----------------------------------------------------------------------------
 

-#include "proxmark3.h"
+#include "../include/proxmark3.h"

 #include "apps.h"
 #include "util.h"
 #include "string.h"
 
 #include "apps.h"
 #include "util.h"
 #include "string.h"
 

-#include "iso14443crc.h"
+#include "../common/iso14443crc.h"

 
 //static void GetSamplesFor14443(int weTx, int n);
 
 
 //static void GetSamplesFor14443(int weTx, int n);
 

-#define DEMOD_TRACE_SIZE 4096
+/*#define DEMOD_TRACE_SIZE 4096

 #define READER_TAG_BUFFER_SIZE 2048
 #define TAG_READER_BUFFER_SIZE 2048
 #define DEMOD_DMA_BUFFER_SIZE 1024
 #define READER_TAG_BUFFER_SIZE 2048
 #define TAG_READER_BUFFER_SIZE 2048
 #define DEMOD_DMA_BUFFER_SIZE 1024

-
+*/

 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using
 // a UART kind of thing that's implemented in software. When we get a
 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using
 // a UART kind of thing that's implemented in software. When we get a


@@ -39,87 +39,87 @@
 //-----------------------------------------------------------------------------
 static void CodeIso14443bAsTag(const uint8_t *cmd, int len)
 {
 //-----------------------------------------------------------------------------
 static void CodeIso14443bAsTag(const uint8_t *cmd, int len)
 {

-    int i;
-
-    ToSendReset();
-
-    // Transmit a burst of ones, as the initial thing that lets the
-    // reader get phase sync. This (TR1) must be > 80/fs, per spec,
-    // but tag that I've tried (a Paypass) exceeds that by a fair bit,
-    // so I will too.
-    for(i = 0; i < 20; i++) {
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-    }
-
-    // Send SOF.
-    for(i = 0; i < 10; i++) {
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-    }
-    for(i = 0; i < 2; i++) {
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-    }
-
-    for(i = 0; i < len; i++) {
-        int j;
-        uint8_t b = cmd[i];
-
-        // Start bit
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-
-        // Data bits
-        for(j = 0; j < 8; j++) {
-            if(b & 1) {
-                ToSendStuffBit(1);
-                ToSendStuffBit(1);
-                ToSendStuffBit(1);
-                ToSendStuffBit(1);
-            } else {
-                ToSendStuffBit(0);
-                ToSendStuffBit(0);
-                ToSendStuffBit(0);
-                ToSendStuffBit(0);
-            }
-            b >>= 1;
-        }
-
-        // Stop bit
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-    }
-
-    // Send SOF.
-    for(i = 0; i < 10; i++) {
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-        ToSendStuffBit(0);
-    }
-    for(i = 0; i < 10; i++) {
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-    }
-
-    // Convert from last byte pos to length
-    ToSendMax++;
-
-    // Add a few more for slop
-    ToSendMax += 2;
+       int i;
+
+       ToSendReset();
+
+       // Transmit a burst of ones, as the initial thing that lets the
+       // reader get phase sync. This (TR1) must be > 80/fs, per spec,
+       // but tag that I've tried (a Paypass) exceeds that by a fair bit,
+       // so I will too.
+       for(i = 0; i < 20; i++) {
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+       }
+
+       // Send SOF.
+       for(i = 0; i < 10; i++) {
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+       }
+       for(i = 0; i < 2; i++) {
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+       }
+
+       for(i = 0; i < len; i++) {
+               int j;
+               uint8_t b = cmd[i];
+
+               // Start bit
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+
+               // Data bits
+               for(j = 0; j < 8; j++) {
+                       if(b & 1) {
+                               ToSendStuffBit(1);
+                               ToSendStuffBit(1);
+                               ToSendStuffBit(1);
+                               ToSendStuffBit(1);
+                       } else {
+                               ToSendStuffBit(0);
+                               ToSendStuffBit(0);
+                               ToSendStuffBit(0);
+                               ToSendStuffBit(0);
+                       }
+                       b >>= 1;
+               }
+
+               // Stop bit
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+       }
+
+       // Send SOF.
+       for(i = 0; i < 10; i++) {
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+               ToSendStuffBit(0);
+       }
+       for(i = 0; i < 10; i++) {
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+       }
+
+       // Convert from last byte pos to length
+       ToSendMax++;
+
+       // Add a few more for slop
+       ToSendMax += 2;

 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------


@@ -127,19 +127,19 @@ static void CodeIso14443bAsTag(const uint8_t *cmd, int len)
 // variables.
 //-----------------------------------------------------------------------------
 static struct {
 // variables.
 //-----------------------------------------------------------------------------
 static struct {

-    enum {
-        STATE_UNSYNCD,
-        STATE_GOT_FALLING_EDGE_OF_SOF,
-        STATE_AWAITING_START_BIT,
-        STATE_RECEIVING_DATA,
-        STATE_ERROR_WAIT
-    }       state;
-    uint16_t    shiftReg;
-    int     bitCnt;
-    int     byteCnt;
-    int     byteCntMax;
-    int     posCnt;
-    uint8_t   *output;
+       enum {
+               STATE_UNSYNCD,
+               STATE_GOT_FALLING_EDGE_OF_SOF,
+               STATE_AWAITING_START_BIT,
+               STATE_RECEIVING_DATA,
+               STATE_ERROR_WAIT
+       }       state;
+       uint16_t    shiftReg;
+       int     bitCnt;
+       int     byteCnt;
+       int     byteCntMax;
+       int     posCnt;
+       uint8_t   *output;

 } Uart;
 
 /* Receive & handle a bit coming from the reader.
 } Uart;
 
 /* Receive & handle a bit coming from the reader.


@@ -153,126 +153,126 @@ static struct {
  */
 static int Handle14443UartBit(int bit)
 {
  */
 static int Handle14443UartBit(int bit)
 {

-    switch(Uart.state) {
-        case STATE_UNSYNCD:
-               LED_A_OFF();
-            if(!bit) {
-                // we went low, so this could be the beginning
-                // of an SOF
-                Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF;
-                Uart.posCnt = 0;
-                Uart.bitCnt = 0;
-            }
-            break;
-
-        case STATE_GOT_FALLING_EDGE_OF_SOF:
-            Uart.posCnt++;
-            if(Uart.posCnt == 2) {
-                if(bit) {
-                    if(Uart.bitCnt >= 10) {
-                        // we've seen enough consecutive
-                        // zeros that it's a valid SOF
-                        Uart.posCnt = 0;
-                        Uart.byteCnt = 0;
-                        Uart.state = STATE_AWAITING_START_BIT;
-                        LED_A_ON(); // Indicate we got a valid SOF
-                    } else {
-                        // didn't stay down long enough
-                        // before going high, error
-                        Uart.state = STATE_ERROR_WAIT;
-                    }
-                } else {
-                    // do nothing, keep waiting
-                }
-                Uart.bitCnt++;
-            }
-            if(Uart.posCnt >= 4) Uart.posCnt = 0;
-            if(Uart.bitCnt > 14) {
-                // Give up if we see too many zeros without
-                // a one, too.
-                Uart.state = STATE_ERROR_WAIT;
-            }
-            break;
-
-        case STATE_AWAITING_START_BIT:
-            Uart.posCnt++;
-            if(bit) {
-                if(Uart.posCnt > 25) {
-                    // stayed high for too long between
-                    // characters, error
-                    Uart.state = STATE_ERROR_WAIT;
-                }
-            } else {
-                // falling edge, this starts the data byte
-                Uart.posCnt = 0;
-                Uart.bitCnt = 0;
-                Uart.shiftReg = 0;
-                Uart.state = STATE_RECEIVING_DATA;
-                LED_A_ON(); // Indicate we're receiving
-            }
-            break;
-
-        case STATE_RECEIVING_DATA:
-            Uart.posCnt++;
-            if(Uart.posCnt == 2) {
-                // time to sample a bit
-                Uart.shiftReg >>= 1;
-                if(bit) {
-                    Uart.shiftReg |= 0x200;
-                }
-                Uart.bitCnt++;
-            }
-            if(Uart.posCnt >= 4) {
-                Uart.posCnt = 0;
-            }
-            if(Uart.bitCnt == 10) {
-                if((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001))
-                {
-                    // this is a data byte, with correct
-                    // start and stop bits
-                    Uart.output[Uart.byteCnt] = (Uart.shiftReg >> 1) & 0xff;
-                    Uart.byteCnt++;
-
-                    if(Uart.byteCnt >= Uart.byteCntMax) {
-                        // Buffer overflowed, give up
-                        Uart.posCnt = 0;
-                        Uart.state = STATE_ERROR_WAIT;
-                    } else {
-                        // so get the next byte now
-                        Uart.posCnt = 0;
-                        Uart.state = STATE_AWAITING_START_BIT;
-                    }
-                } else if(Uart.shiftReg == 0x000) {
-                    // this is an EOF byte
-                       LED_A_OFF(); // Finished receiving
-                    return TRUE;
-                } else {
-                    // this is an error
-                    Uart.posCnt = 0;
-                    Uart.state = STATE_ERROR_WAIT;
-                }
-            }
-            break;
-
-        case STATE_ERROR_WAIT:
-            // We're all screwed up, so wait a little while
-            // for whatever went wrong to finish, and then
-            // start over.
-            Uart.posCnt++;
-            if(Uart.posCnt > 10) {
-                Uart.state = STATE_UNSYNCD;
-            }
-            break;
-
-        default:
-            Uart.state = STATE_UNSYNCD;
-            break;
-    }
-
-    // This row make the error blew circular buffer in hf 14b snoop
-    //if (Uart.state == STATE_ERROR_WAIT) LED_A_OFF(); // Error
-
-    return FALSE;
+       switch(Uart.state) {
+               case STATE_UNSYNCD:
+                       LED_A_OFF();
+                       if(!bit) {
+                               // we went low, so this could be the beginning
+                               // of an SOF
+                               Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF;
+                               Uart.posCnt = 0;
+                               Uart.bitCnt = 0;
+                       }
+                       break;
+
+               case STATE_GOT_FALLING_EDGE_OF_SOF:
+                       Uart.posCnt++;
+                       if(Uart.posCnt == 2) {
+                               if(bit) {
+                                       if(Uart.bitCnt >= 10) {
+                                               // we've seen enough consecutive
+                                               // zeros that it's a valid SOF
+                                               Uart.posCnt = 0;
+                                               Uart.byteCnt = 0;
+                                               Uart.state = STATE_AWAITING_START_BIT;
+                                               LED_A_ON(); // Indicate we got a valid SOF
+                                       } else {
+                                               // didn't stay down long enough
+                                               // before going high, error
+                                               Uart.state = STATE_ERROR_WAIT;
+                                       }
+                               } else {
+                                       // do nothing, keep waiting
+                               }
+                               Uart.bitCnt++;
+                       }
+                       if(Uart.posCnt >= 4) Uart.posCnt = 0;
+                       if(Uart.bitCnt > 14) {
+                               // Give up if we see too many zeros without
+                               // a one, too.
+                               Uart.state = STATE_ERROR_WAIT;
+                       }
+                       break;
+
+               case STATE_AWAITING_START_BIT:
+                       Uart.posCnt++;
+                       if(bit) {
+                               if(Uart.posCnt > 25) {
+                                       // stayed high for too long between
+                                       // characters, error
+                                       Uart.state = STATE_ERROR_WAIT;
+                               }
+                       } else {
+                               // falling edge, this starts the data byte
+                               Uart.posCnt = 0;
+                               Uart.bitCnt = 0;
+                               Uart.shiftReg = 0;
+                               Uart.state = STATE_RECEIVING_DATA;
+                               LED_A_ON(); // Indicate we're receiving
+                       }
+                       break;
+
+               case STATE_RECEIVING_DATA:
+                       Uart.posCnt++;
+                       if(Uart.posCnt == 2) {
+                               // time to sample a bit
+                               Uart.shiftReg >>= 1;
+                               if(bit) {
+                                       Uart.shiftReg |= 0x200;
+                               }
+                               Uart.bitCnt++;
+                       }
+                       if(Uart.posCnt >= 4) {
+                               Uart.posCnt = 0;
+                       }
+                       if(Uart.bitCnt == 10) {
+                               if((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001))
+                               {
+                                       // this is a data byte, with correct
+                                       // start and stop bits
+                                       Uart.output[Uart.byteCnt] = (Uart.shiftReg >> 1) & 0xff;
+                                       Uart.byteCnt++;
+
+                                       if(Uart.byteCnt >= Uart.byteCntMax) {
+                                               // Buffer overflowed, give up
+                                               Uart.posCnt = 0;
+                                               Uart.state = STATE_ERROR_WAIT;
+                                       } else {
+                                               // so get the next byte now
+                                               Uart.posCnt = 0;
+                                               Uart.state = STATE_AWAITING_START_BIT;
+                                       }
+                               } else if(Uart.shiftReg == 0x000) {
+                                       // this is an EOF byte
+                                       LED_A_OFF(); // Finished receiving
+                                       return TRUE;
+                               } else {
+                                       // this is an error
+                                       Uart.posCnt = 0;
+                                       Uart.state = STATE_ERROR_WAIT;
+                               }
+                       }
+                       break;
+
+               case STATE_ERROR_WAIT:
+                       // We're all screwed up, so wait a little while
+                       // for whatever went wrong to finish, and then
+                       // start over.
+                       Uart.posCnt++;
+                       if(Uart.posCnt > 10) {
+                               Uart.state = STATE_UNSYNCD;
+                       }
+                       break;
+
+               default:
+                       Uart.state = STATE_UNSYNCD;
+                       break;
+       }
+
+       // This row make the error blew circular buffer in hf 14b snoop
+       //if (Uart.state == STATE_ERROR_WAIT) LED_A_OFF(); // Error
+
+       return FALSE;

 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------


@@ -286,42 +286,42 @@ static int Handle14443UartBit(int bit)
 //-----------------------------------------------------------------------------
 static int GetIso14443CommandFromReader(uint8_t *received, int *len, int maxLen)
 {
 //-----------------------------------------------------------------------------
 static int GetIso14443CommandFromReader(uint8_t *received, int *len, int maxLen)
 {

-    uint8_t mask;
-    int i, bit;
-
-    // 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_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);
-
-
-    // Now run a `software UART' on the stream of incoming samples.
-    Uart.output = received;
-    Uart.byteCntMax = maxLen;
-    Uart.state = STATE_UNSYNCD;
-
-    for(;;) {
-        WDT_HIT();
-
-        if(BUTTON_PRESS()) return FALSE;
-
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = 0x00;
-        }
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-
-            mask = 0x80;
-            for(i = 0; i < 8; i++, mask >>= 1) {
-                bit = (b & mask);
-                if(Handle14443UartBit(bit)) {
-                    *len = Uart.byteCnt;
-                    return TRUE;
-                }
-            }
-        }
-    }
+       uint8_t mask;
+       int i, bit;
+
+       // 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_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);
+
+
+       // Now run a `software UART' on the stream of incoming samples.
+       Uart.output = received;
+       Uart.byteCntMax = maxLen;
+       Uart.state = STATE_UNSYNCD;
+
+       for(;;) {
+               WDT_HIT();
+
+               if(BUTTON_PRESS()) return FALSE;
+
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x00;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       mask = 0x80;
+                       for(i = 0; i < 8; i++, mask >>= 1) {
+                               bit = (b & mask);
+                               if(Handle14443UartBit(bit)) {
+                                       *len = Uart.byteCnt;
+                                       return TRUE;
+                               }
+                       }
+               }
+       }

 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------


@@ -330,99 +330,99 @@ static int GetIso14443CommandFromReader(uint8_t *received, int *len, int maxLen)
 //-----------------------------------------------------------------------------
 void SimulateIso14443Tag(void)
 {
 //-----------------------------------------------------------------------------
 void SimulateIso14443Tag(void)
 {

-    static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
-    static const uint8_t response1[] = {
-        0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22,
-        0x00, 0x21, 0x85, 0x5e, 0xd7
-    };
+       static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
+       static const uint8_t response1[] = {
+               0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22,
+               0x00, 0x21, 0x85, 0x5e, 0xd7
+       };

 
 

-    uint8_t *resp;
-    int respLen;
+       uint8_t *resp;
+       int respLen;

 
 

-    uint8_t *resp1 = (((uint8_t *)BigBuf) + 800);
-    int resp1Len;
+       uint8_t *resp1 = BigBuf_get_addr() + 800;
+       int resp1Len;

 
 

-    uint8_t *receivedCmd = (uint8_t *)BigBuf;
-    int len;
+       uint8_t *receivedCmd = BigBuf_get_addr();
+       int len;

 
 

-    int i;
+       int i;

 
 

-    int cmdsRecvd = 0;
+       int cmdsRecvd = 0;

 
 

-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-    memset(receivedCmd, 0x44, 400);
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       memset(receivedCmd, 0x44, 400);

 
 

-    CodeIso14443bAsTag(response1, sizeof(response1));
-    memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
+       CodeIso14443bAsTag(response1, sizeof(response1));
+       memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;

 
 

-    // We need to listen to the high-frequency, peak-detected path.
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-    FpgaSetupSsc();
+       // We need to listen to the high-frequency, peak-detected path.
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+       FpgaSetupSsc();

 
 

-    cmdsRecvd = 0;
+       cmdsRecvd = 0;

 
 

-    for(;;) {
-        uint8_t b1, b2;
+       for(;;) {
+               uint8_t b1, b2;

 
 

-        if(!GetIso14443CommandFromReader(receivedCmd, &len, 100)) {
+               if(!GetIso14443CommandFromReader(receivedCmd, &len, 100)) {

                Dbprintf("button pressed, received %d commands", cmdsRecvd);
                break;
                Dbprintf("button pressed, received %d commands", cmdsRecvd);
                break;

-        }
-
-        // Good, look at the command now.
-
-        if(len == sizeof(cmd1) && memcmp(receivedCmd, cmd1, len)==0) {
-            resp = resp1; respLen = resp1Len;
-        } else {
-            Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd);
-            // And print whether the CRC fails, just for good measure
-            ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
-            if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
-                // Not so good, try again.
-                DbpString("+++CRC fail");
-            } else {
-                DbpString("CRC passes");
-            }
-            break;
-        }
-
-        memset(receivedCmd, 0x44, 32);
-
-        cmdsRecvd++;
-
-        if(cmdsRecvd > 0x30) {
-            DbpString("many commands later...");
-            break;
-        }
-
-        if(respLen <= 0) continue;
-
-        // Modulate BPSK
-        // Signal field is off with the appropriate LED
-        LED_D_OFF();
-        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK);
-        AT91C_BASE_SSC->SSC_THR = 0xff;
-        FpgaSetupSsc();
-
-        // Transmit the response.
-        i = 0;
-        for(;;) {
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-                uint8_t b = resp[i];
-
-                AT91C_BASE_SSC->SSC_THR = b;
-
-                i++;
-                if(i > respLen) {
-                    break;
-                }
-            }
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-                volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-                (void)b;
-            }
-        }
-    }
+               }
+
+               // Good, look at the command now.
+
+               if(len == sizeof(cmd1) && memcmp(receivedCmd, cmd1, len)==0) {
+                       resp = resp1; respLen = resp1Len;
+               } else {
+                       Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd);
+                       // And print whether the CRC fails, just for good measure
+                       ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
+                       if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
+                               // Not so good, try again.
+                               DbpString("+++CRC fail");
+                       } else {
+                               DbpString("CRC passes");
+                       }
+                       break;
+               }
+
+               memset(receivedCmd, 0x44, 32);
+
+               cmdsRecvd++;
+
+               if(cmdsRecvd > 0x30) {
+                       DbpString("many commands later...");
+                       break;
+               }
+
+               if(respLen <= 0) continue;
+
+               // Modulate BPSK
+               // Signal field is off with the appropriate LED
+               LED_D_OFF();
+               FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK);
+               AT91C_BASE_SSC->SSC_THR = 0xff;
+               FpgaSetupSsc();
+
+               // Transmit the response.
+               i = 0;
+               for(;;) {
+                       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                               uint8_t b = resp[i];
+
+                               AT91C_BASE_SSC->SSC_THR = b;
+
+                               i++;
+                               if(i > respLen) {
+                                       break;
+                               }
+                       }
+                       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                               volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+                               (void)b;
+                       }
+               }
+       }

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


@@ -433,25 +433,25 @@ void SimulateIso14443Tag(void)
 //=============================================================================
 
 static struct {
 //=============================================================================
 
 static struct {

-    enum {
-        DEMOD_UNSYNCD,
-        DEMOD_PHASE_REF_TRAINING,
-        DEMOD_AWAITING_FALLING_EDGE_OF_SOF,
-        DEMOD_GOT_FALLING_EDGE_OF_SOF,
-        DEMOD_AWAITING_START_BIT,
-        DEMOD_RECEIVING_DATA,
-        DEMOD_ERROR_WAIT
-    }       state;
-    int     bitCount;
-    int     posCount;
-    int     thisBit;
-    int     metric;
-    int     metricN;
-    uint16_t    shiftReg;
-    uint8_t   *output;
-    int     len;
-    int     sumI;
-    int     sumQ;
+       enum {
+               DEMOD_UNSYNCD,
+               DEMOD_PHASE_REF_TRAINING,
+               DEMOD_AWAITING_FALLING_EDGE_OF_SOF,
+               DEMOD_GOT_FALLING_EDGE_OF_SOF,
+               DEMOD_AWAITING_START_BIT,
+               DEMOD_RECEIVING_DATA,
+               DEMOD_ERROR_WAIT
+       }       state;
+       int     bitCount;
+       int     posCount;
+       int     thisBit;
+       int     metric;
+       int     metricN;
+       uint16_t    shiftReg;
+       uint8_t   *output;
+       int     len;
+       int     sumI;
+       int     sumQ;

 } Demod;
 
 /*
 } Demod;
 
 /*


@@ -467,154 +467,179 @@ static struct {
  */
 static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
 {
  */
 static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
 {

-    int v;
+       int v;

 
 

-    // The soft decision on the bit uses an estimate of just the
-    // quadrant of the reference angle, not the exact angle.
+       // The soft decision on the bit uses an estimate of just the
+       // quadrant of the reference angle, not the exact angle.

 #define MAKE_SOFT_DECISION() { \
 #define MAKE_SOFT_DECISION() { \

-        if(Demod.sumI > 0) { \
-            v = ci; \
-        } else { \
-            v = -ci; \
-        } \
-        if(Demod.sumQ > 0) { \
-            v += cq; \
-        } else { \
-            v -= cq; \
-        } \
-    }
-
-    switch(Demod.state) {
-        case DEMOD_UNSYNCD:
-            v = ci;
-            if(v < 0) v = -v;
-            if(cq > 0) {
-                v += cq;
-            } else {
-                v -= cq;
-            }
-            if(v > 40) {
-                Demod.posCount = 0;
-                Demod.state = DEMOD_PHASE_REF_TRAINING;
-                Demod.sumI = 0;
-                Demod.sumQ = 0;
-            }
-            break;
-
-        case DEMOD_PHASE_REF_TRAINING:
-            if(Demod.posCount < 8) {
-                Demod.sumI += ci;
-                Demod.sumQ += cq;
-            } else if(Demod.posCount > 100) {
-                // error, waited too long
-                Demod.state = DEMOD_UNSYNCD;
-            } else {
-                MAKE_SOFT_DECISION();
-                if(v < 0) {
-                    Demod.state = DEMOD_AWAITING_FALLING_EDGE_OF_SOF;
-                    Demod.posCount = 0;
-                }
-            }
-            Demod.posCount++;
-            break;
-
-        case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
-            MAKE_SOFT_DECISION();
-            if(v < 0) {
-                Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
-                Demod.posCount = 0;
-            } else {
-                if(Demod.posCount > 100) {
-                    Demod.state = DEMOD_UNSYNCD;
-                }
-            }
-            Demod.posCount++;
-            break;
-
-        case DEMOD_GOT_FALLING_EDGE_OF_SOF:
-            MAKE_SOFT_DECISION();
-            if(v > 0) {
-                if(Demod.posCount < 12) {
-                    Demod.state = DEMOD_UNSYNCD;
-                } else {
-                    LED_C_ON(); // Got SOF
-                    Demod.state = DEMOD_AWAITING_START_BIT;
-                    Demod.posCount = 0;
-                    Demod.len = 0;
-                    Demod.metricN = 0;
-                    Demod.metric = 0;
-                }
-            } else {
-                if(Demod.posCount > 100) {
-                    Demod.state = DEMOD_UNSYNCD;
-                }
-            }
-            Demod.posCount++;
-            break;
-
-        case DEMOD_AWAITING_START_BIT:
-            MAKE_SOFT_DECISION();
-            if(v > 0) {
-                if(Demod.posCount > 10) {
-                    Demod.state = DEMOD_UNSYNCD;
-                }
-            } else {
-                Demod.bitCount = 0;
-                Demod.posCount = 1;
-                Demod.thisBit = v;
-                Demod.shiftReg = 0;
-                Demod.state = DEMOD_RECEIVING_DATA;
-            }
-            break;
-
-        case DEMOD_RECEIVING_DATA:
-            MAKE_SOFT_DECISION();
-            if(Demod.posCount == 0) {
-                Demod.thisBit = v;
-                Demod.posCount = 1;
-            } else {
-                Demod.thisBit += v;
-
-                if(Demod.thisBit > 0) {
-                    Demod.metric += Demod.thisBit;
-                } else {
-                    Demod.metric -= Demod.thisBit;
-                }
-                (Demod.metricN)++;
-
-                Demod.shiftReg >>= 1;
-                if(Demod.thisBit > 0) {
-                    Demod.shiftReg |= 0x200;
-                }
-
-                Demod.bitCount++;
-                if(Demod.bitCount == 10) {
-                    uint16_t s = Demod.shiftReg;
-                    if((s & 0x200) && !(s & 0x001)) {
-                        uint8_t b = (s >> 1);
-                        Demod.output[Demod.len] = b;
-                        Demod.len++;
-                        Demod.state = DEMOD_AWAITING_START_BIT;
-                    } else if(s == 0x000) {
-                        // This is EOF
-                       LED_C_OFF();
-                        Demod.state = DEMOD_UNSYNCD;
-                        return TRUE;
-                    } else {
-                        Demod.state = DEMOD_UNSYNCD;
-                    }
-                }
-                Demod.posCount = 0;
-            }
-            break;
-
-        default:
-            Demod.state = DEMOD_UNSYNCD;
-            break;
-    }
-
-    if (Demod.state == DEMOD_UNSYNCD) LED_C_OFF(); // Not synchronized...
-    return FALSE;
+               if(Demod.sumI > 0) { \
+                       v = ci; \
+               } else { \
+                       v = -ci; \
+               } \
+               if(Demod.sumQ > 0) { \
+                       v += cq; \
+               } else { \
+                       v -= cq; \
+               } \
+       }
+
+       switch(Demod.state) {
+               case DEMOD_UNSYNCD:
+                       v = ci;
+                       if(v < 0) v = -v;
+                       if(cq > 0) {
+                               v += cq;
+                       } else {
+                               v -= cq;
+                       }
+                       if(v > 40) {
+                               Demod.posCount = 0;
+                               Demod.state = DEMOD_PHASE_REF_TRAINING;
+                               Demod.sumI = 0;
+                               Demod.sumQ = 0;
+                       }
+                       break;
+
+               case DEMOD_PHASE_REF_TRAINING:
+                       if(Demod.posCount < 8) {
+                               Demod.sumI += ci;
+                               Demod.sumQ += cq;
+                       } else if(Demod.posCount > 100) {
+                               // error, waited too long
+                               Demod.state = DEMOD_UNSYNCD;
+                       } else {
+                               MAKE_SOFT_DECISION();
+                               if(v < 0) {
+                                       Demod.state = DEMOD_AWAITING_FALLING_EDGE_OF_SOF;
+                                       Demod.posCount = 0;
+                               }
+                       }
+                       Demod.posCount++;
+                       break;
+
+               case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
+                       MAKE_SOFT_DECISION();
+                       if(v < 0) {
+                               Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
+                               Demod.posCount = 0;
+                       } else {
+                               if(Demod.posCount > 100) {
+                                       Demod.state = DEMOD_UNSYNCD;
+                               }
+                       }
+                       Demod.posCount++;
+                       break;
+
+               case DEMOD_GOT_FALLING_EDGE_OF_SOF:
+                       MAKE_SOFT_DECISION();
+                       if(v > 0) {
+                               if(Demod.posCount < 12) {
+                                       Demod.state = DEMOD_UNSYNCD;
+                               } else {
+                                       LED_C_ON(); // Got SOF
+                                       Demod.state = DEMOD_AWAITING_START_BIT;
+                                       Demod.posCount = 0;
+                                       Demod.len = 0;
+                                       Demod.metricN = 0;
+                                       Demod.metric = 0;
+                               }
+                       } else {
+                               if(Demod.posCount > 100) {
+                                       Demod.state = DEMOD_UNSYNCD;
+                               }
+                       }
+                       Demod.posCount++;
+                       break;
+
+               case DEMOD_AWAITING_START_BIT:
+                       MAKE_SOFT_DECISION();
+                       if(v > 0) {
+                               if(Demod.posCount > 10) {
+                                       Demod.state = DEMOD_UNSYNCD;
+                               }
+                       } else {
+                               Demod.bitCount = 0;
+                               Demod.posCount = 1;
+                               Demod.thisBit = v;
+                               Demod.shiftReg = 0;
+                               Demod.state = DEMOD_RECEIVING_DATA;
+                       }
+                       break;
+
+               case DEMOD_RECEIVING_DATA:
+                       MAKE_SOFT_DECISION();
+                       if(Demod.posCount == 0) {
+                               Demod.thisBit = v;
+                               Demod.posCount = 1;
+                       } else {
+                               Demod.thisBit += v;
+
+                               if(Demod.thisBit > 0) {
+                                       Demod.metric += Demod.thisBit;
+                               } else {
+                                       Demod.metric -= Demod.thisBit;
+                               }
+                               (Demod.metricN)++;
+
+                               Demod.shiftReg >>= 1;
+                               if(Demod.thisBit > 0) {
+                                       Demod.shiftReg |= 0x200;
+                               }
+
+                               Demod.bitCount++;
+                               if(Demod.bitCount == 10) {
+                                       uint16_t s = Demod.shiftReg;
+                                       if((s & 0x200) && !(s & 0x001)) {
+                                               uint8_t b = (s >> 1);
+                                               Demod.output[Demod.len] = b;
+                                               Demod.len++;
+                                               Demod.state = DEMOD_AWAITING_START_BIT;
+                                       } else if(s == 0x000) {
+                                               // This is EOF
+                                               LED_C_OFF();
+                                               Demod.state = DEMOD_UNSYNCD;
+                                               return TRUE;
+                                       } else {
+                                               Demod.state = DEMOD_UNSYNCD;
+                                       }
+                               }
+                               Demod.posCount = 0;
+                       }
+                       break;
+
+               default:
+                       Demod.state = DEMOD_UNSYNCD;
+                       break;
+       }
+
+       if (Demod.state == DEMOD_UNSYNCD) LED_C_OFF(); // Not synchronized...
+       return FALSE;
+}
+static void DemodReset()
+{
+       // Clear out the state of the "UART" that receives from the tag.
+       Demod.len = 0;
+       Demod.state = DEMOD_UNSYNCD;
+       memset(Demod.output, 0x00, MAX_FRAME_SIZE);
+}
+static void DemodInit(uint8_t *data)
+{
+       Demod.output = data;
+       DemodReset();
+}
+
+static void UartReset()
+{
+       Uart.byteCntMax = MAX_FRAME_SIZE;
+       Uart.state = STATE_UNSYNCD;
+       Uart.byteCnt = 0;
+       Uart.bitCnt = 0;
+}
+static void UartInit(uint8_t *data)
+{
+       Uart.output = data;
+       UartReset();

 }
 
 /*
 }
 
 /*


@@ -625,79 +650,77 @@ static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
  */
 static void GetSamplesFor14443Demod(int weTx, int n, int quiet)
 {
  */
 static void GetSamplesFor14443Demod(int weTx, int n, int quiet)
 {

-    int max = 0;
-    int gotFrame = FALSE;
-
-//#   define DMA_BUFFER_SIZE 8
-    int8_t *dmaBuf;
-
-    int lastRxCounter;
-    int8_t *upTo;
-
-    int ci, cq;
-
-    int samples = 0;
-
-    // Clear out the state of the "UART" that receives from the tag.
-    memset(BigBuf, 0x00, 400);
-    Demod.output = (uint8_t *)BigBuf;
-    Demod.len = 0;
-    Demod.state = DEMOD_UNSYNCD;
-
-    // And the UART that receives from the reader
-    Uart.output = (((uint8_t *)BigBuf) + 1024);
-    Uart.byteCntMax = 100;
-    Uart.state = STATE_UNSYNCD;
-
-    // Setup for the DMA.
-    dmaBuf = (int8_t *)(BigBuf + 32);
-    upTo = dmaBuf;
-    lastRxCounter = DEMOD_DMA_BUFFER_SIZE;
-    FpgaSetupSscDma((uint8_t *)dmaBuf, DEMOD_DMA_BUFFER_SIZE);
-
-    // Signal field is ON with the appropriate LED:
-    if (weTx) LED_D_ON(); else LED_D_OFF();
-    // And put the FPGA in the appropriate mode
-    FpgaWriteConfWord(
-       FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
-       (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
-
-    for(;;) {
-        int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
-        if(behindBy > max) max = behindBy;
-
-        while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (DEMOD_DMA_BUFFER_SIZE-1))
-                    > 2)
-        {
-            ci = upTo[0];
-            cq = upTo[1];
-            upTo += 2;
-            if(upTo - dmaBuf > DEMOD_DMA_BUFFER_SIZE) {
-                upTo -= DEMOD_DMA_BUFFER_SIZE;
-                AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
-                AT91C_BASE_PDC_SSC->PDC_RNCR = DEMOD_DMA_BUFFER_SIZE;
-            }
-            lastRxCounter -= 2;
-            if(lastRxCounter <= 0) {
-                lastRxCounter += DEMOD_DMA_BUFFER_SIZE;
-            }
-
-            samples += 2;
-
-            Handle14443UartBit(1);
-            Handle14443UartBit(1);
-
-            if(Handle14443SamplesDemod(ci, cq)) {
-                gotFrame = 1;
-            }
-        }
-
-        if(samples > 2000) {
-            break;
-        }
-    }
-    AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
-    if (!quiet) Dbprintf("%x %x %x", max, gotFrame, Demod.len);
+       int max = 0;
+       int gotFrame = FALSE;
+       int lastRxCounter, ci, cq, samples = 0;
+
+       // Allocate memory from BigBuf for some buffers
+       // free all previous allocations first
+       BigBuf_free();
+       
+       // The command (reader -> tag) that we're receiving.
+       uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+       
+       // The response (tag -> reader) that we're receiving.
+       uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
+       
+       // The DMA buffer, used to stream samples from the FPGA
+       uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+
+       // Set up the demodulator for tag -> reader responses.
+       DemodInit(receivedResponse);
+       // Set up the demodulator for the reader -> tag commands
+       UartInit(receivedCmd);
+
+       // Setup and start DMA.
+       FpgaSetupSscDma(dmaBuf, DMA_BUFFER_SIZE);
+
+       uint8_t *upTo= dmaBuf;
+       lastRxCounter = DMA_BUFFER_SIZE;
+
+       // Signal field is ON with the appropriate LED:
+       if (weTx) LED_D_ON(); else LED_D_OFF();
+       // And put the FPGA in the appropriate mode
+       FpgaWriteConfWord(
+               FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
+               (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
+
+       for(;;) {
+               int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
+               if(behindBy > max) max = behindBy;
+
+               while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (DMA_BUFFER_SIZE-1))
+                                       > 2)
+               {
+                       ci = upTo[0];
+                       cq = upTo[1];
+                       upTo += 2;
+                       if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
+                               upTo -= DMA_BUFFER_SIZE;
+                               AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
+                               AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+                       }
+                       lastRxCounter -= 2;
+                       if(lastRxCounter <= 0) {
+                               lastRxCounter += DMA_BUFFER_SIZE;
+                       }
+
+                       samples += 2;
+
+                       Handle14443UartBit(1);
+                       Handle14443UartBit(1);
+
+                       if(Handle14443SamplesDemod(ci, cq)) {
+                               gotFrame = 1;
+                       }
+               }
+
+               if(samples > 2000) {
+                       break;
+               }
+       }
+       AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
+       if (!quiet) Dbprintf("%x %x %x", max, gotFrame, Demod.len);

        //Tracing
        if (tracing && Demod.len > 0) {
                uint8_t parity[MAX_PARITY_SIZE];
        //Tracing
        if (tracing && Demod.len > 0) {
                uint8_t parity[MAX_PARITY_SIZE];


@@ -713,29 +736,29 @@ static void GetSamplesFor14443Demod(int weTx, int n, int quiet)
 //-----------------------------------------------------------------------------
 /*static void GetSamplesFor14443(int weTx, int n)
 {
 //-----------------------------------------------------------------------------
 /*static void GetSamplesFor14443(int weTx, int n)
 {

-    uint8_t *dest = (uint8_t *)BigBuf;
-    int c;
-
-    FpgaWriteConfWord(
-       FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
-       (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
-
-    c = 0;
-    for(;;) {
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = 0x43;
-        }
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            int8_t b;
-            b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
-
-            dest[c++] = (uint8_t)b;
-
-            if(c >= n) {
-                break;
-            }
-        }
-    }
+       uint8_t *dest = (uint8_t *)BigBuf;
+       int c;
+
+       FpgaWriteConfWord(
+               FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
+               (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
+
+       c = 0;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x43;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       int8_t b;
+                       b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       dest[c++] = (uint8_t)b;
+
+                       if(c >= n) {
+                               break;
+                       }
+               }
+       }

 }*/
 
 //-----------------------------------------------------------------------------
 }*/
 
 //-----------------------------------------------------------------------------


@@ -743,49 +766,49 @@ static void GetSamplesFor14443Demod(int weTx, int n, int quiet)
 //-----------------------------------------------------------------------------
 static void TransmitFor14443(void)
 {
 //-----------------------------------------------------------------------------
 static void TransmitFor14443(void)
 {

-    int c;
+       int c;

 
 

-    FpgaSetupSsc();
+       FpgaSetupSsc();

 
 

-    while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-        AT91C_BASE_SSC->SSC_THR = 0xff;
-    }
+       while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+               AT91C_BASE_SSC->SSC_THR = 0xff;
+       }

 
 

-    // Signal field is ON with the appropriate Red LED
+       // Signal field is ON with the appropriate Red LED

        LED_D_ON();
        // Signal we are transmitting with the Green LED
        LED_B_ON();
        FpgaWriteConfWord(
        LED_D_ON();
        // Signal we are transmitting with the Green LED
        LED_B_ON();
        FpgaWriteConfWord(

-       FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
-
-    for(c = 0; c < 10;) {
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = 0xff;
-            c++;
-        }
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-            (void)r;
-        }
-        WDT_HIT();
-    }
-
-    c = 0;
-    for(;;) {
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = ToSend[c];
-            c++;
-            if(c >= ToSendMax) {
-                break;
-            }
-        }
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-            (void)r;
-        }
-        WDT_HIT();
-    }
-    LED_B_OFF(); // Finished sending
+               FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
+
+       for(c = 0; c < 10;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0xff;
+                       c++;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+                       (void)r;
+               }
+               WDT_HIT();
+       }
+
+       c = 0;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = ToSend[c];
+                       c++;
+                       if(c >= ToSendMax) {
+                               break;
+                       }
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+                       (void)r;
+               }
+               WDT_HIT();
+       }
+       LED_B_OFF(); // Finished sending

 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------


@@ -794,54 +817,54 @@ static void TransmitFor14443(void)
 //-----------------------------------------------------------------------------
 static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 {
 //-----------------------------------------------------------------------------
 static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 {

-    int i, j;
-    uint8_t b;
-
-    ToSendReset();
-
-    // Establish initial reference level
-    for(i = 0; i < 40; i++) {
-        ToSendStuffBit(1);
-    }
-    // Send SOF
-    for(i = 0; i < 10; i++) {
-        ToSendStuffBit(0);
-    }
-
-    for(i = 0; i < len; i++) {
-        // Stop bits/EGT
-        ToSendStuffBit(1);
-        ToSendStuffBit(1);
-        // Start bit
-        ToSendStuffBit(0);
-        // Data bits
-        b = cmd[i];
-        for(j = 0; j < 8; j++) {
-            if(b & 1) {
-                ToSendStuffBit(1);
-            } else {
-                ToSendStuffBit(0);
-            }
-            b >>= 1;
-        }
-    }
-    // Send EOF
-    ToSendStuffBit(1);
-    for(i = 0; i < 10; i++) {
-        ToSendStuffBit(0);
-    }
-    for(i = 0; i < 8; i++) {
-        ToSendStuffBit(1);
-    }
-
-    // And then a little more, to make sure that the last character makes
-    // it out before we switch to rx mode.
-    for(i = 0; i < 24; i++) {
-        ToSendStuffBit(1);
-    }
-
-    // Convert from last character reference to length
-    ToSendMax++;
+       int i, j;
+       uint8_t b;
+
+       ToSendReset();
+
+       // Establish initial reference level
+       for(i = 0; i < 40; i++) {
+               ToSendStuffBit(1);
+       }
+       // Send SOF
+       for(i = 0; i < 10; i++) {
+               ToSendStuffBit(0);
+       }
+
+       for(i = 0; i < len; i++) {
+               // Stop bits/EGT
+               ToSendStuffBit(1);
+               ToSendStuffBit(1);
+               // Start bit
+               ToSendStuffBit(0);
+               // Data bits
+               b = cmd[i];
+               for(j = 0; j < 8; j++) {
+                       if(b & 1) {
+                               ToSendStuffBit(1);
+                       } else {
+                               ToSendStuffBit(0);
+                       }
+                       b >>= 1;
+               }
+       }
+       // Send EOF
+       ToSendStuffBit(1);
+       for(i = 0; i < 10; i++) {
+               ToSendStuffBit(0);
+       }
+       for(i = 0; i < 8; i++) {
+               ToSendStuffBit(1);
+       }
+
+       // And then a little more, to make sure that the last character makes
+       // it out before we switch to rx mode.
+       for(i = 0; i < 24; i++) {
+               ToSendStuffBit(1);
+       }
+
+       // Convert from last character reference to length
+       ToSendMax++;

 }
 
 //-----------------------------------------------------------------------------
 }
 
 //-----------------------------------------------------------------------------


@@ -854,9 +877,9 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 //-----------------------------------------------------------------------------
 void AcquireRawAdcSamplesIso14443(uint32_t parameter)
 {
 //-----------------------------------------------------------------------------
 void AcquireRawAdcSamplesIso14443(uint32_t parameter)
 {

-    uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
+       uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };

 
 

-    SendRawCommand14443B(sizeof(cmd1),1,1,cmd1);
+       SendRawCommand14443B(sizeof(cmd1),1,1,cmd1);

 }
 
 /**
 }
 
 /**


@@ -887,126 +910,126 @@ void ReadSTMemoryIso14443(uint32_t dwLast)
        clear_trace();
        set_tracing(TRUE);
 
        clear_trace();
        set_tracing(TRUE);
 

-    uint8_t i = 0x00;
+       uint8_t i = 0x00;

 
 

-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-    // Make sure that we start from off, since the tags are stateful;
-    // confusing things will happen if we don't reset them between reads.
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-    SpinDelay(200);
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       // Make sure that we start from off, since the tags are stateful;
+       // confusing things will happen if we don't reset them between reads.
+       LED_D_OFF();
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       SpinDelay(200);

 
 

-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-    FpgaSetupSsc();
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+       FpgaSetupSsc();

 
 

-    // Now give it time to spin up.
-    // Signal field is on with the appropriate LED
-    LED_D_ON();
-    FpgaWriteConfWord(
-       FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
-    SpinDelay(200);
+       // Now give it time to spin up.
+       // Signal field is on with the appropriate LED
+       LED_D_ON();
+       FpgaWriteConfWord(
+               FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
+       SpinDelay(200);

 
 

-    // First command: wake up the tag using the INITIATE command
-    uint8_t cmd1[] = { 0x06, 0x00, 0x97, 0x5b};
+       // First command: wake up the tag using the INITIATE command
+       uint8_t cmd1[] = { 0x06, 0x00, 0x97, 0x5b};

 
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 //    LED_A_ON();
 
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 //    LED_A_ON();

-    GetSamplesFor14443Demod(TRUE, 2000,TRUE);
+       GetSamplesFor14443Demod(TRUE, 2000,TRUE);

 //    LED_A_OFF();
 
 //    LED_A_OFF();
 

-    if (Demod.len == 0) {
+       if (Demod.len == 0) {

        DbpString("No response from tag");
        return;
        DbpString("No response from tag");
        return;

-    } else {
+       } else {

        Dbprintf("Randomly generated UID from tag (+ 2 byte CRC): %x %x %x",
                Demod.output[0], Demod.output[1],Demod.output[2]);
        Dbprintf("Randomly generated UID from tag (+ 2 byte CRC): %x %x %x",
                Demod.output[0], Demod.output[1],Demod.output[2]);

-    }
-    // There is a response, SELECT the uid
-    DbpString("Now SELECT tag:");
-    cmd1[0] = 0x0E; // 0x0E is SELECT
-    cmd1[1] = Demod.output[0];
-    ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
+       }
+       // There is a response, SELECT the uid
+       DbpString("Now SELECT tag:");
+       cmd1[0] = 0x0E; // 0x0E is SELECT
+       cmd1[1] = Demod.output[0];
+       ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);

        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 
 //    LED_A_ON();
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 
 //    LED_A_ON();

-    GetSamplesFor14443Demod(TRUE, 2000,TRUE);
+       GetSamplesFor14443Demod(TRUE, 2000,TRUE);

 //    LED_A_OFF();
 //    LED_A_OFF();

-    if (Demod.len != 3) {
+       if (Demod.len != 3) {

        Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
        return;
        Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
        return;

-    }
-    // Check the CRC of the answer:
-    ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
-    if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {
+       }
+       // Check the CRC of the answer:
+       ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
+       if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {

        DbpString("CRC Error reading select response.");
        return;
        DbpString("CRC Error reading select response.");
        return;

-    }
-    // Check response from the tag: should be the same UID as the command we just sent:
-    if (cmd1[1] != Demod.output[0]) {
+       }
+       // Check response from the tag: should be the same UID as the command we just sent:
+       if (cmd1[1] != Demod.output[0]) {

        Dbprintf("Bad response to SELECT from Tag, aborting: %x %x", cmd1[1], Demod.output[0]);
        return;
        Dbprintf("Bad response to SELECT from Tag, aborting: %x %x", cmd1[1], Demod.output[0]);
        return;

-    }
-    // Tag is now selected,
-    // First get the tag's UID:
-    cmd1[0] = 0x0B;
-    ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);
+       }
+       // Tag is now selected,
+       // First get the tag's UID:
+       cmd1[0] = 0x0B;
+       ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);

        CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one
 
 //    LED_A_ON();
        CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one
 
 //    LED_A_ON();

-    GetSamplesFor14443Demod(TRUE, 2000,TRUE);
+       GetSamplesFor14443Demod(TRUE, 2000,TRUE);

 //    LED_A_OFF();
 //    LED_A_OFF();

-    if (Demod.len != 10) {
+       if (Demod.len != 10) {

        Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
        return;
        Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
        return;

-    }
-    // The check the CRC of the answer (use cmd1 as temporary variable):
-    ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]);
-           if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {
+       }
+       // The check the CRC of the answer (use cmd1 as temporary variable):
+       ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]);
+                  if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {

        Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
                (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);
        // Do not return;, let's go on... (we should retry, maybe ?)
        Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
                (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);
        // Do not return;, let's go on... (we should retry, maybe ?)

-    }
-    Dbprintf("Tag UID (64 bits): %08x %08x",
+       }
+       Dbprintf("Tag UID (64 bits): %08x %08x",

        (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
        (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]);
 
        (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
        (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]);
 

-    // Now loop to read all 16 blocks, address from 0 to last block
-    Dbprintf("Tag memory dump, block 0 to %d",dwLast);
-    cmd1[0] = 0x08;
-    i = 0x00;
-    dwLast++;
-    for (;;) {
-           if (i == dwLast) {
-                   DbpString("System area block (0xff):");
-                   i = 0xff;
-           }
-           cmd1[1] = i;
-           ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
+       // Now loop to read all 16 blocks, address from 0 to last block
+       Dbprintf("Tag memory dump, block 0 to %d",dwLast);
+       cmd1[0] = 0x08;
+       i = 0x00;
+       dwLast++;
+       for (;;) {
+                  if (i == dwLast) {
+                       DbpString("System area block (0xff):");
+                       i = 0xff;
+               }
+               cmd1[1] = i;
+               ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);

                CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 
 //         LED_A_ON();
                CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 
 //         LED_A_ON();

-           GetSamplesFor14443Demod(TRUE, 2000,TRUE);
+               GetSamplesFor14443Demod(TRUE, 2000,TRUE);

 //         LED_A_OFF();
 //         LED_A_OFF();

-           if (Demod.len != 6) { // Check if we got an answer from the tag
+               if (Demod.len != 6) { // Check if we got an answer from the tag

                DbpString("Expected 6 bytes from tag, got less...");
                return;
                DbpString("Expected 6 bytes from tag, got less...");
                return;

-           }
-           // The check the CRC of the answer (use cmd1 as temporary variable):
-           ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
-            if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
+               }
+               // The check the CRC of the answer (use cmd1 as temporary variable):
+               ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
+                       if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {

                Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
                        (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);
                // Do not return;, let's go on... (we should retry, maybe ?)
                Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
                        (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);
                // Do not return;, let's go on... (we should retry, maybe ?)

-           }
-           // Now print out the memory location:
-           Dbprintf("Address=%x, Contents=%x, CRC=%x", i,
+               }
+               // Now print out the memory location:
+               Dbprintf("Address=%x, Contents=%x, CRC=%x", i,

                (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0],
                (Demod.output[4]<<8)+Demod.output[5]);
                (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0],
                (Demod.output[4]<<8)+Demod.output[5]);

-           if (i == 0xff) {
+               if (i == 0xff) {

                break;
                break;

-           }
-           i++;
-    }
+               }
+               i++;
+       }

 }
 
 
 }
 
 


@@ -1029,165 +1052,147 @@ void ReadSTMemoryIso14443(uint32_t dwLast)
  */
 void RAMFUNC SnoopIso14443(void)
 {
  */
 void RAMFUNC SnoopIso14443(void)
 {

-    // 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.
-    int triggered = TRUE;
-
-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-    // The command (reader -> tag) that we're working on receiving.
-    uint8_t *receivedCmd = (uint8_t *)(BigBuf) + DEMOD_TRACE_SIZE;
-    // The response (tag -> reader) that we're working on receiving.
-    uint8_t *receivedResponse = (uint8_t *)(BigBuf) + DEMOD_TRACE_SIZE + READER_TAG_BUFFER_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;
-    int traceLen = 0;
-
-    // The DMA buffer, used to stream samples from the FPGA.
-    int8_t *dmaBuf = (int8_t *)(BigBuf) + DEMOD_TRACE_SIZE + READER_TAG_BUFFER_SIZE + TAG_READER_BUFFER_SIZE;
-    int lastRxCounter;
-    int8_t *upTo;
-    int ci, cq;
-    int maxBehindBy = 0;
-
-    // Count of samples received so far, so that we can include timing
-    // information in the trace buffer.
-    int samples = 0;
-
-    // Initialize the trace buffer
-    memset(trace, 0x44, DEMOD_TRACE_SIZE);
-
-    // Set up the demodulator for tag -> reader responses.
-    Demod.output = receivedResponse;
-    Demod.len = 0;
-    Demod.state = DEMOD_UNSYNCD;
-
-    // And the reader -> tag commands
-    memset(&Uart, 0, sizeof(Uart));
-    Uart.output = receivedCmd;
-    Uart.byteCntMax = 100;
-    Uart.state = STATE_UNSYNCD;
-
-    // Print some debug information about the buffer sizes
-    Dbprintf("Snooping buffers initialized:");
-    Dbprintf("  Trace: %i bytes", DEMOD_TRACE_SIZE);
-    Dbprintf("  Reader -> tag: %i bytes", READER_TAG_BUFFER_SIZE);
-    Dbprintf("  tag -> Reader: %i bytes", TAG_READER_BUFFER_SIZE);
-    Dbprintf("  DMA: %i bytes", DEMOD_DMA_BUFFER_SIZE);
-
-    // And put the FPGA in the appropriate mode
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(
-       FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
-       FPGA_HF_READER_RX_XCORR_SNOOP);
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-
-    // Setup for the DMA.
-    FpgaSetupSsc();
-    upTo = dmaBuf;
-    lastRxCounter = DEMOD_DMA_BUFFER_SIZE;
-    FpgaSetupSscDma((uint8_t *)dmaBuf, DEMOD_DMA_BUFFER_SIZE);
-               
-    LED_A_ON();
+       // 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.
+       int triggered = TRUE;
+
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       BigBuf_free();
+
+       clear_trace();
+       set_tracing(TRUE);
+
+       // The DMA buffer, used to stream samples from the FPGA
+       uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+       int lastRxCounter;
+       uint8_t *upTo;
+       int ci, cq;
+       int maxBehindBy = 0;
+
+       // Count of samples received so far, so that we can include timing
+       // information in the trace buffer.
+       int samples = 0;
+
+       DemodInit(BigBuf_malloc(MAX_FRAME_SIZE));
+       UartInit(BigBuf_malloc(MAX_FRAME_SIZE));
+
+       // Print some debug information about the buffer sizes
+       Dbprintf("Snooping buffers initialized:");
+       Dbprintf("  Trace: %i bytes", BigBuf_max_traceLen());
+       Dbprintf("  Reader -> tag: %i bytes", MAX_FRAME_SIZE);
+       Dbprintf("  tag -> Reader: %i bytes", MAX_FRAME_SIZE);
+       Dbprintf("  DMA: %i bytes", DMA_BUFFER_SIZE);
+
+       // Signal field is off with the appropriate LED
+       LED_D_OFF();
+
+       // And put the FPGA in the appropriate mode
+       FpgaWriteConfWord(
+               FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
+               FPGA_HF_READER_RX_XCORR_SNOOP);
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+       // Setup for the DMA.
+       FpgaSetupSsc();
+       upTo = dmaBuf;
+       lastRxCounter = DMA_BUFFER_SIZE;
+       FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
+       uint8_t parity[MAX_PARITY_SIZE];
+       LED_A_ON();

                
                

-    // And now we loop, receiving samples.
-    for(;;) {
-       int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
-                                (DEMOD_DMA_BUFFER_SIZE-1);
-        if(behindBy > maxBehindBy) {
-            maxBehindBy = behindBy;
-            if(behindBy > (DEMOD_DMA_BUFFER_SIZE-2)) { // TODO: understand whether we can increase/decrease as we want or not?
-                Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
-                goto done;
-            }
-        }
-        if(behindBy < 2) continue;
-
-        ci = upTo[0];
-        cq = upTo[1];
-        upTo += 2;
-        lastRxCounter -= 2;
-        if(upTo - dmaBuf > DEMOD_DMA_BUFFER_SIZE) {
-            upTo -= DEMOD_DMA_BUFFER_SIZE;
-            lastRxCounter += DEMOD_DMA_BUFFER_SIZE;
-            AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
-            AT91C_BASE_PDC_SSC->PDC_RNCR = DEMOD_DMA_BUFFER_SIZE;
-        }
-
-        samples += 2;
-
-#define HANDLE_BIT_IF_BODY \
-                       if(triggered && tracing) {\
-                               uint8_t parity[MAX_PARITY_SIZE];\
-                               GetParity(receivedCmd, Uart.byteCnt, parity);\
-                               LogTrace(receivedCmd,Uart.byteCnt,samples, samples,parity,TRUE);\
-                               if(!tracing) {\
-                                       DbpString("Reached trace limit");\
-                                       break;\
-                               }\
-                       }\
-            /* And ready to receive another command. */ \
-            memset(&Uart, 0, sizeof(Uart)); \
-            Uart.output = receivedCmd; \
-            Uart.byteCntMax = 100; \
-            Uart.state = STATE_UNSYNCD; \
-            /* And also reset the demod code, which might have been */ \
-            /* false-triggered by the commands from the reader. */ \
-            memset(&Demod, 0, sizeof(Demod)); \
-            Demod.output = receivedResponse; \
-            Demod.state = DEMOD_UNSYNCD; \
-
-        if(Handle14443UartBit(ci & 1)) {
-            HANDLE_BIT_IF_BODY
-        }
-        if(Handle14443UartBit(cq & 1)) {
-            HANDLE_BIT_IF_BODY
-        }
-
-        if(Handle14443SamplesDemod(ci, cq)) {
+       // And now we loop, receiving samples.
+       for(;;) {
+               int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
+                                                               (DMA_BUFFER_SIZE-1);
+               if(behindBy > maxBehindBy) {
+                       maxBehindBy = behindBy;
+                       if(behindBy > (9*DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not?
+                               Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
+                               break;
+                       }
+               }
+               if(behindBy < 2) continue;
+
+               ci = upTo[0];
+               cq = upTo[1];
+               upTo += 2;
+               lastRxCounter -= 2;
+               if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
+                       upTo -= DMA_BUFFER_SIZE;
+                       lastRxCounter += DMA_BUFFER_SIZE;
+                       AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
+                       AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+               }
+
+               samples += 2;
+
+               if(Handle14443UartBit(ci & 1)) {
+                       if(triggered && tracing) {
+                               GetParity(Uart.output, Uart.byteCnt, parity);
+                               LogTrace(Uart.output,Uart.byteCnt,samples, samples,parity,TRUE);
+                       }
+                       if(Uart.byteCnt==0) Dbprintf("[1] Error, Uart.byteCnt==0, Uart.bitCnt=%d", Uart.bitCnt);
+
+                       /* 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();
+               }
+               if(Handle14443UartBit(cq & 1)) {
+                       if(triggered && tracing) {
+                               GetParity(Uart.output, Uart.byteCnt, parity);
+                               LogTrace(Uart.output,Uart.byteCnt,samples, samples,parity,TRUE);
+                       }
+                       if(Uart.byteCnt==0) Dbprintf("[2] Error, Uart.byteCnt==0, Uart.bitCnt=%d", Uart.bitCnt);
+
+                       /* 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();
+               }
+
+               if(Handle14443SamplesDemod(ci, cq)) {

 
                        //Use samples as a time measurement
                        if(tracing)
                        {
                                uint8_t parity[MAX_PARITY_SIZE];
 
                        //Use samples as a time measurement
                        if(tracing)
                        {
                                uint8_t parity[MAX_PARITY_SIZE];

-                               GetParity(receivedResponse, Demod.len, parity);
-                               LogTrace(receivedResponse,Demod.len,samples, samples,parity,FALSE);
-                               if(!tracing) {
-                                       DbpString("Reached trace limit");
-                                       break;
-                               }
+                               GetParity(Demod.output, Demod.len, parity);
+                               LogTrace(Demod.output,Demod.len,samples, samples,parity,FALSE);

                        }
                        }

-            triggered = TRUE;
-            LED_A_OFF();
-            LED_B_ON();
-
-            // And ready to receive another response.
-            memset(&Demod, 0, sizeof(Demod));
-            Demod.output = receivedResponse;
-            Demod.state = DEMOD_UNSYNCD;
-        }
-       WDT_HIT();
-
-        if(BUTTON_PRESS()) {
-            DbpString("cancelled");
-            goto done;
-        }
-    }
-
-done:
+                       triggered = TRUE;
+                       LED_A_OFF();
+                       LED_B_ON();
+
+                       // And ready to receive another response.
+                       DemodReset();
+               }
+               WDT_HIT();
+
+               if(!tracing) {
+                       DbpString("Reached trace limit");
+                       break;
+               }
+
+               if(BUTTON_PRESS()) {
+                       DbpString("cancelled");
+                       break;
+               }
+       }
+       FpgaDisableSscDma();

        LED_A_OFF();
        LED_B_OFF();
        LED_C_OFF();
        LED_A_OFF();
        LED_B_OFF();
        LED_C_OFF();

-  AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
+       AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;

        DbpString("Snoop statistics:");
        Dbprintf("  Max behind by: %i", maxBehindBy);
        Dbprintf("  Uart State: %x", Uart.state);
        Dbprintf("  Uart ByteCnt: %i", Uart.byteCnt);
        Dbprintf("  Uart ByteCntMax: %i", Uart.byteCntMax);
        DbpString("Snoop statistics:");
        Dbprintf("  Max behind by: %i", maxBehindBy);
        Dbprintf("  Uart State: %x", Uart.state);
        Dbprintf("  Uart ByteCnt: %i", Uart.byteCnt);
        Dbprintf("  Uart ByteCntMax: %i", Uart.byteCntMax);

-       Dbprintf("  Trace length: %i", traceLen);
+       Dbprintf("  Trace length: %i", BigBuf_get_traceLen());

 }
 
 /*
 }
 
 /*


@@ -1205,41 +1210,41 @@ done:
 
 void SendRawCommand14443B(uint32_t datalen, uint32_t recv,uint8_t powerfield, uint8_t data[])
 {
 
 void SendRawCommand14443B(uint32_t datalen, uint32_t recv,uint8_t powerfield, uint8_t data[])
 {

-    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-    if(!powerfield)
-    {
-        // Make sure that we start from off, since the tags are stateful;
-        // confusing things will happen if we don't reset them between reads.
-        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-        LED_D_OFF();
-        SpinDelay(200);
-    }
-
-    if(!GETBIT(GPIO_LED_D))
-    {
-        SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-        FpgaSetupSsc();
-
-        // Now give it time to spin up.
-        // Signal field is on with the appropriate LED
-        LED_D_ON();
-        FpgaWriteConfWord(
-            FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
-        SpinDelay(200);
-    }
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       if(!powerfield)
+       {
+               // Make sure that we start from off, since the tags are stateful;
+               // confusing things will happen if we don't reset them between reads.
+               FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+               LED_D_OFF();
+               SpinDelay(200);
+       }
+
+       if(!GETBIT(GPIO_LED_D))
+       {
+               SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+               FpgaSetupSsc();
+
+               // Now give it time to spin up.
+               // Signal field is on with the appropriate LED
+               LED_D_ON();
+               FpgaWriteConfWord(
+                       FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
+               SpinDelay(200);
+       }

 
        CodeAndTransmit14443bAsReader(data, datalen);
 
 
        CodeAndTransmit14443bAsReader(data, datalen);
 

-    if(recv)
-    {
-        uint16_t iLen = MIN(Demod.len,USB_CMD_DATA_SIZE);
-        GetSamplesFor14443Demod(TRUE, 2000, TRUE);
-        cmd_send(CMD_ACK,iLen,0,0,Demod.output,iLen);
-    }
-    if(!powerfield)
-    {
-        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-        LED_D_OFF();
-    }
+       if(recv)
+       {
+               uint16_t iLen = MIN(Demod.len,USB_CMD_DATA_SIZE);
+               GetSamplesFor14443Demod(TRUE, 2000, TRUE);
+               cmd_send(CMD_ACK,iLen,0,0,Demod.output,iLen);
+       }
+       if(!powerfield)
+       {
+               FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+               LED_D_OFF();
+       }

 }
 
 }