git.zerfleddert.de Git - proxmark3-svn/blobdiff

// Jonathan Westhues, split Nov 2006

// Modified by Greg Jones, Jan 2009

// Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011

// Jonathan Westhues, split Nov 2006

// Modified by Greg Jones, Jan 2009

// Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011

-// Modified by piwi, Oct 2018

+// Modified by piwi, Oct 2018

//

// This code is licensed to you under the terms of the GNU GPL, version 2 or,

// at your option, any later version. See the LICENSE.txt file for the text of

//

// This code is licensed to you under the terms of the GNU GPL, version 2 or,

// at your option, any later version. See the LICENSE.txt file for the text of

// transmission modes from tag to reader. As of Oct 2018 this code supports

// both reader modes and the high speed variant with one subcarrier from card to reader.

// As long as the card fully support ISO 15693 this is no problem, since the

// transmission modes from tag to reader. As of Oct 2018 this code supports

// both reader modes and the high speed variant with one subcarrier from card to reader.

// As long as the card fully support ISO 15693 this is no problem, since the

-// reader chooses both data rates, but some non-standard tags do not.

+// reader chooses both data rates, but some non-standard tags do not.

// For card simulation, the code supports both high and low speed modes with one subcarrier.

//

// VCD (reader) -> VICC (tag)

// 1 out of 256:

// For card simulation, the code supports both high and low speed modes with one subcarrier.

//

// VCD (reader) -> VICC (tag)

// 1 out of 256:

-// data rate: 1,66 kbit/s (fc/8192)

-// used for long range

+// data rate: 1,66 kbit/s (fc/8192)

+// used for long range

// 1 out of 4:

-// data rate: 26,48 kbit/s (fc/512)

-// used for short range, high speed

+// data rate: 26,48 kbit/s (fc/512)

+// used for short range, high speed

//

// VICC (tag) -> VCD (reader)

// Modulation:

//

// VICC (tag) -> VCD (reader)

// Modulation:

-// ASK / one subcarrier (423,75 khz)

-// FSK / two subcarriers (423,75 khz && 484,28 khz)

+// ASK / one subcarrier (423,75 khz)

+// FSK / two subcarriers (423,75 khz && 484,28 khz)

// Data Rates / Modes:

-// low ASK: 6,62 kbit/s

-// low FSK: 6.67 kbit/s

-// high ASK: 26,48 kbit/s

-// high FSK: 26,69 kbit/s

+// low ASK: 6,62 kbit/s

+// low FSK: 6.67 kbit/s

+// high ASK: 26,48 kbit/s

+// high FSK: 26,69 kbit/s

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

// *) add anti-collision support for inventory-commands

// *) read security status of a block

// *) sniffing and simulation do not support two subcarrier modes.

// *) add anti-collision support for inventory-commands

// *) read security status of a block

// *) sniffing and simulation do not support two subcarrier modes.

-// *) remove or refactor code under "depricated"

+// *) remove or refactor code under "deprecated"

// *) document all the functions

+#include "iso15693.h"

#include "proxmark3.h"

#include "util.h"

#include "proxmark3.h"

#include "util.h"

#include "string.h"

#include "iso15693tools.h"

#include "protocols.h"

#include "string.h"

#include "iso15693tools.h"

#include "protocols.h"

-#include "cmd.h"

+#include "usb_cdc.h"

+#include "BigBuf.h"

+#include "fpgaloader.h"

#define arraylen(x) (sizeof(x)/sizeof((x)[0]))

+// Delays in SSP_CLK ticks.

+// SSP_CLK runs at 13,56MHz / 32 = 423.75kHz when simulating a tag

+#define DELAY_READER_TO_ARM 8

+#define DELAY_ARM_TO_READER 0

+//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when acting as reader. All values should be multiples of 16

+#define DELAY_ARM_TO_TAG 16

+#define DELAY_TAG_TO_ARM 32

+//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when snooping. All values should be multiples of 16

+#define DELAY_TAG_TO_ARM_SNOOP 32

+#define DELAY_READER_TO_ARM_SNOOP 32

+

+// times in samples @ 212kHz when acting as reader

+//#define ISO15693_READER_TIMEOUT 80 // 80/212kHz = 378us, nominal t1_max=313,9us

+#define ISO15693_READER_TIMEOUT 330 // 330/212kHz = 1558us, should be even enough for iClass tags responding to ACTALL

+#define ISO15693_READER_TIMEOUT_WRITE 4700 // 4700/212kHz = 22ms, nominal 20ms

+

static int DEBUG = 0;

+

///////////////////////////////////////////////////////////////////////

// ISO 15693 Part 2 - Air Interface

///////////////////////////////////////////////////////////////////////

// ISO 15693 Part 2 - Air Interface

-// This section basicly contains transmission and receiving of bits

+// This section basically contains transmission and receiving of bits

///////////////////////////////////////////////////////////////////////

-#define FrameSOF Iso15693FrameSOF

-#define Logic0 Iso15693Logic0

-#define Logic1 Iso15693Logic1

-#define FrameEOF Iso15693FrameEOF

-

-#define Crc(data,datalen) Iso15693Crc(data,datalen)

-#define AddCrc(data,datalen) Iso15693AddCrc(data,datalen)

-#define sprintUID(target,uid) Iso15693sprintUID(target,uid)

+// buffers

+#define ISO15693_DMA_BUFFER_SIZE 256 // must be a power of 2

+#define ISO15693_MAX_RESPONSE_LENGTH 36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet

+#define ISO15693_MAX_COMMAND_LENGTH 45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet

-// approximate amplitude=sqrt(ci^2+cq^2) by amplitude = max(|ci|,|cq|) + 1/2*min(|ci|,|cq|)

-#define AMPLITUDE(ci, cq) (MAX(ABS(ci), ABS(cq)) + MIN(ABS(ci), ABS(cq))/2)

-// buffers

-#define ISO15693_DMA_BUFFER_SIZE 128

-#define ISO15693_MAX_RESPONSE_LENGTH 36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet

-#define ISO15693_MAX_COMMAND_LENGTH 45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet

+// specific LogTrace function for ISO15693: the duration needs to be scaled because otherwise it won't fit into a uint16_t

+bool LogTrace_ISO15693(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_start, uint32_t timestamp_end, uint8_t *parity, bool readerToTag) {

+ uint32_t duration = timestamp_end - timestamp_start;

+ duration /= 32;

+ timestamp_end = timestamp_start + duration;

+ return LogTrace(btBytes, iLen, timestamp_start, timestamp_end, parity, readerToTag);

+}

-// timing. Delays in SSP_CLK ticks.

-#define DELAY_READER_TO_ARM 8

-#define DELAY_ARM_TO_READER 1

-#define DELAY_ISO15693_VCD_TO_VICC 132 // 132/423.75kHz = 311.5us from end of EOF to start of tag response

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

// Signal Processing

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

// Signal Processing

// resulting data rate is 26.48 kbit/s (fc/512)

// cmd ... data

// n ... length of data

// resulting data rate is 26.48 kbit/s (fc/512)

// cmd ... data

// n ... length of data

-static void CodeIso15693AsReader(uint8_t *cmd, int n)

-{

- int i, j;

+void CodeIso15693AsReader(uint8_t *cmd, int n) {

ToSendReset();

- // Give it a bit of slack at the beginning

- for(i = 0; i < 24; i++) {

- ToSendStuffBit(1);

- }

-

// SOF for 1of4

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

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

- for(j = 0; j < 8; j += 2) {

- int these = (cmd[i] >> j) & 3;

+ ToSend[++ToSendMax] = 0x84; //10000100

+

+ // data

+ for (int i = 0; i < n; i++) {

+ for (int j = 0; j < 8; j += 2) {

+ int these = (cmd[i] >> j) & 0x03;

switch(these) {

case 0:

switch(these) {

case 0:

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

+ ToSend[++ToSendMax] = 0x40; //01000000

break;

case 1:

break;

case 1:

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

+ ToSend[++ToSendMax] = 0x10; //00010000

break;

case 2:

break;

case 2:

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

+ ToSend[++ToSendMax] = 0x04; //00000100

break;

case 3:

break;

case 3:

- ToSendStuffBit(1);

- ToSendStuffBit(0);

+ ToSend[++ToSendMax] = 0x01; //00000001

break;

}

break;

}

+

// EOF

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

-

- // Fill remainder of last byte with 1

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

- ToSendStuffBit(1);

- }

+ ToSend[++ToSendMax] = 0x20; //0010 + 0000 padding

+

+ ToSendMax++;

}

+

+// Encode EOF only

+static void CodeIso15693AsReaderEOF() {

+ ToSendReset();

+ ToSend[++ToSendMax] = 0x20;

+ ToSendMax++;

+}

+

// encode data using "1 out of 256" scheme

// data rate is 1,66 kbit/s (fc/8192)

// is designed for more robust communication over longer distances

static void CodeIso15693AsReader256(uint8_t *cmd, int n)

{

// encode data using "1 out of 256" scheme

// data rate is 1,66 kbit/s (fc/8192)

// is designed for more robust communication over longer distances

static void CodeIso15693AsReader256(uint8_t *cmd, int n)

{

- int i, j;

-

ToSendReset();

- // Give it a bit of slack at the beginning

- for(i = 0; i < 24; i++) {

- ToSendStuffBit(1);

- }

-

// SOF for 1of256

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- ToSendStuffBit(0);

-

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

- for (j = 0; j<=255; j++) {

- if (cmd[i]==j) {

- ToSendStuffBit(1);

+ ToSend[++ToSendMax] = 0x81; //10000001

+

+ // data

+ for(int i = 0; i < n; i++) {

+ for (int j = 0; j <= 255; j++) {

+ if (cmd[i] == j) {

ToSendStuffBit(0);

- } else {

- ToSendStuffBit(1);

ToSendStuffBit(1);

+ } else {

+ ToSendStuffBit(0);

}

+

// EOF

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

-

- // Fill remainder of last byte with 1

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

- ToSendStuffBit(1);

- }

+ ToSend[++ToSendMax] = 0x20; //0010 + 0000 padding

ToSendMax++;

}

ToSendMax++;

}

-static void CodeIso15693AsTag(uint8_t *cmd, int n)

-{

+// static uint8_t encode4Bits(const uint8_t b) {

+ // uint8_t c = b & 0xF;

+ // // OTA, the least significant bits first

+ // // The columns are

+ // // 1 - Bit value to send

+ // // 2 - Reversed (big-endian)

+ // // 3 - Manchester Encoded

+ // // 4 - Hex values

+

+ // switch(c){

+ // // 1 2 3 4

+ // case 15: return 0x55; // 1111 -> 1111 -> 01010101 -> 0x55

+ // case 14: return 0x95; // 1110 -> 0111 -> 10010101 -> 0x95

+ // case 13: return 0x65; // 1101 -> 1011 -> 01100101 -> 0x65

+ // case 12: return 0xa5; // 1100 -> 0011 -> 10100101 -> 0xa5

+ // case 11: return 0x59; // 1011 -> 1101 -> 01011001 -> 0x59

+ // case 10: return 0x99; // 1010 -> 0101 -> 10011001 -> 0x99

+ // case 9: return 0x69; // 1001 -> 1001 -> 01101001 -> 0x69

+ // case 8: return 0xa9; // 1000 -> 0001 -> 10101001 -> 0xa9

+ // case 7: return 0x56; // 0111 -> 1110 -> 01010110 -> 0x56

+ // case 6: return 0x96; // 0110 -> 0110 -> 10010110 -> 0x96

+ // case 5: return 0x66; // 0101 -> 1010 -> 01100110 -> 0x66

+ // case 4: return 0xa6; // 0100 -> 0010 -> 10100110 -> 0xa6

+ // case 3: return 0x5a; // 0011 -> 1100 -> 01011010 -> 0x5a

+ // case 2: return 0x9a; // 0010 -> 0100 -> 10011010 -> 0x9a

+ // case 1: return 0x6a; // 0001 -> 1000 -> 01101010 -> 0x6a

+ // default: return 0xaa; // 0000 -> 0000 -> 10101010 -> 0xaa

+

+ // }

+// }

+

+static const uint8_t encode_4bits[16] = { 0xaa, 0x6a, 0x9a, 0x5a, 0xa6, 0x66, 0x96, 0x56, 0xa9, 0x69, 0x99, 0x59, 0xa5, 0x65, 0x95, 0x55 };

+

+void CodeIso15693AsTag(uint8_t *cmd, size_t len) {

+ /*

+ * SOF comprises 3 parts;

+ * * An unmodulated time of 56.64 us

+ * * 24 pulses of 423.75 kHz (fc/32)

+ * * A logic 1, which starts with an unmodulated time of 18.88us

+ * followed by 8 pulses of 423.75kHz (fc/32)

+ *

+ * EOF comprises 3 parts:

+ * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated

+ * time of 18.88us.

+ * - 24 pulses of fc/32

+ * - An unmodulated time of 56.64 us

+ *

+ * A logic 0 starts with 8 pulses of fc/32

+ * followed by an unmodulated time of 256/fc (~18,88us).

+ *

+ * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by

+ * 8 pulses of fc/32 (also 18.88us)

+ *

+ * A bit here becomes 8 pulses of fc/32. Therefore:

+ * The SOF can be written as 00011101 = 0x1D

+ * The EOF can be written as 10111000 = 0xb8

+ * A logic 1 is 01

+ * A logic 0 is 10

+ *

+ * */

+

ToSendReset();

// SOF

ToSendReset();

// SOF

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

+ ToSend[++ToSendMax] = 0x1D; // 00011101

// data

- for(int i = 0; i < n; i++) {

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

- if ((cmd[i] >> j) & 0x01) {

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- } else {

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- }

+ for (int i = 0; i < len; i++) {

+ ToSend[++ToSendMax] = encode_4bits[cmd[i] & 0xF];

+ ToSend[++ToSendMax] = encode_4bits[cmd[i] >> 4];

}

// EOF

}

// EOF

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- ToSendStuffBit(0);

+ ToSend[++ToSendMax] = 0xB8; // 10111000

ToSendMax++;

}

// Transmit the command (to the tag) that was placed in cmd[].

ToSendMax++;

}

// Transmit the command (to the tag) that was placed in cmd[].

-static void TransmitTo15693Tag(const uint8_t *cmd, int len)

-{

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);

+void TransmitTo15693Tag(const uint8_t *cmd, int len, uint32_t *start_time) {

+

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_FULL_MOD);

+

+ if (*start_time < DELAY_ARM_TO_TAG) {

+ *start_time = DELAY_ARM_TO_TAG;

+ }

+

+ *start_time = (*start_time - DELAY_ARM_TO_TAG) & 0xfffffff0;

+

+ if (GetCountSspClk() > *start_time) { // we may miss the intended time

+ *start_time = (GetCountSspClk() + 16) & 0xfffffff0; // next possible time

+ }

+

+ while (GetCountSspClk() < *start_time)

+ /* wait */ ;

LED_B_ON();

- for(int c = 0; c < len; ) {

- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {

- AT91C_BASE_SSC->SSC_THR = ~cmd[c];

- c++;

- }

- WDT_HIT();

- }

+ for (int c = 0; c < len; c++) {

+ uint8_t data = cmd[c];

+ for (int i = 0; i < 8; i++) {

+ uint16_t send_word = (data & 0x80) ? 0xffff : 0x0000;

+ while (!(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY))) ;

+ AT91C_BASE_SSC->SSC_THR = send_word;

+ while (!(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY))) ;

+ AT91C_BASE_SSC->SSC_THR = send_word;

+ data <<= 1;

+ }

+ WDT_HIT();

+ }

LED_B_OFF();

+

+ *start_time = *start_time + DELAY_ARM_TO_TAG;

}

+

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

// Transmit the tag response (to the reader) that was placed in cmd[].

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

// Transmit the tag response (to the reader) that was placed in cmd[].

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

-static void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t start_time, bool slow)

-{

+void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t *start_time, uint32_t slot_time, bool slow) {

// don't use the FPGA_HF_SIMULATOR_MODULATE_424K_8BIT minor mode. It would spoil GetCountSspClk()

FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K);

// don't use the FPGA_HF_SIMULATOR_MODULATE_424K_8BIT minor mode. It would spoil GetCountSspClk()

FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K);

- uint8_t shift_delay = start_time & 0x00000007;

- uint8_t bitmask = 0x00;

- for (int i = 0; i < shift_delay; i++) {

- bitmask |= (0x01 << i);

+ uint32_t modulation_start_time = *start_time - DELAY_ARM_TO_READER + 3 * 8; // no need to transfer the unmodulated start of SOF

+

+ while (GetCountSspClk() > (modulation_start_time & 0xfffffff8) + 3) { // we will miss the intended time

+ if (slot_time) {

+ modulation_start_time += slot_time; // use next available slot

+ } else {

+ modulation_start_time = (modulation_start_time & 0xfffffff8) + 8; // next possible time

+ }

}

- while (GetCountSspClk() < (start_time & 0xfffffff8)) ;

- AT91C_BASE_SSC->SSC_THR = 0x00; // clear TXRDY

+ while (GetCountSspClk() < (modulation_start_time & 0xfffffff8))

+ /* wait */ ;

+

+ uint8_t shift_delay = modulation_start_time & 0x00000007;

+

+ *start_time = modulation_start_time + DELAY_ARM_TO_READER - 3 * 8;

LED_C_ON();

uint8_t bits_to_shift = 0x00;

LED_C_ON();

uint8_t bits_to_shift = 0x00;

- for(size_t c = 0; c <= len; c++) {

- uint8_t bits_to_send = bits_to_shift << (8 - shift_delay) | (c==len?0x00:cmd[c]) >> shift_delay;

- bits_to_shift = cmd[c] & bitmask;

- for (int i = 7; i >= 0; i--) {

+ uint8_t bits_to_send = 0x00;

+ for (size_t c = 0; c < len; c++) {

+ for (int i = (c==0?4:7); i >= 0; i--) {

+ uint8_t cmd_bits = ((cmd[c] >> i) & 0x01) ? 0xff : 0x00;

for (int j = 0; j < (slow?4:1); ) {

if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {

for (int j = 0; j < (slow?4:1); ) {

if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {

- if (bits_to_send >> i & 0x01) {

- AT91C_BASE_SSC->SSC_THR = 0xff;

- } else {

- AT91C_BASE_SSC->SSC_THR = 0x00;

- }

+ bits_to_send = bits_to_shift << (8 - shift_delay) | cmd_bits >> shift_delay;

+ AT91C_BASE_SSC->SSC_THR = bits_to_send;

+ bits_to_shift = cmd_bits;

j++;

}

j++;

}

- WDT_HIT();

}

- }

+ }

+ WDT_HIT();

+ }

+ // send the remaining bits, padded with 0:

+ bits_to_send = bits_to_shift << (8 - shift_delay);

+ for ( ; ; ) {

+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {

+ AT91C_BASE_SSC->SSC_THR = bits_to_send;

+ break;

+ }

LED_C_OFF();

}

//=============================================================================

// An ISO 15693 decoder for tag responses (one subcarrier only).

LED_C_OFF();

}

//=============================================================================

// An ISO 15693 decoder for tag responses (one subcarrier only).

-// Uses cross correlation to identify the SOF, each bit, and EOF.

+// Uses cross correlation to identify each bit and EOF.

// This function is called 8 times per bit (every 2 subcarrier cycles).

// Subcarrier frequency fs is 424kHz, 1/fs = 2,36us,

// i.e. function is called every 4,72us

// This function is called 8 times per bit (every 2 subcarrier cycles).

// Subcarrier frequency fs is 424kHz, 1/fs = 2,36us,

// i.e. function is called every 4,72us

// false if we are still waiting for some more

//=============================================================================

// false if we are still waiting for some more

//=============================================================================

-#define SUBCARRIER_DETECT_THRESHOLD 2

-#define SOF_CORRELATOR_LEN (1<<5)

+#define NOISE_THRESHOLD 80 // don't try to correlate noise

+#define MAX_PREVIOUS_AMPLITUDE (-1 - NOISE_THRESHOLD)

typedef struct DecodeTag {

enum {

typedef struct DecodeTag {

enum {

- STATE_TAG_UNSYNCD,

- STATE_TAG_AWAIT_SOF_1,

- STATE_TAG_AWAIT_SOF_2,

+ STATE_TAG_SOF_LOW,

+ STATE_TAG_SOF_RISING_EDGE,

+ STATE_TAG_SOF_HIGH,

+ STATE_TAG_SOF_HIGH_END,

STATE_TAG_RECEIVING_DATA,

- STATE_TAG_AWAIT_EOF

+ STATE_TAG_EOF,

+ STATE_TAG_EOF_TAIL

} state;

int bitCount;

int posCount;

} state;

int bitCount;

int posCount;

SOF_PART2

} lastBit;

uint16_t shiftReg;

SOF_PART2

} lastBit;

uint16_t shiftReg;

+ uint16_t max_len;

uint8_t *output;

int len;

int sum1, sum2;

uint8_t *output;

int len;

int sum1, sum2;

- uint8_t SOF_low;

- uint8_t SOF_high;

- uint8_t SOF_last;

- int32_t SOF_corr;

- int32_t SOF_corr_prev;

- uint8_t SOF_correlator[SOF_CORRELATOR_LEN];

+ int threshold_sof;

+ int threshold_half;

+ uint16_t previous_amplitude;

} DecodeTag_t;

-static int Handle15693SamplesFromTag(int8_t ci, int8_t cq, DecodeTag_t *DecodeTag)

-{

- switch(DecodeTag->state) {

- case STATE_TAG_UNSYNCD:

- // initialize SOF correlator. We are looking for 12 samples low and 12 samples high.

- DecodeTag->SOF_low = 0;

- DecodeTag->SOF_high = 12;

- DecodeTag->SOF_last = 23;

- memset(DecodeTag->SOF_correlator, 0x00, DecodeTag->SOF_last + 1);

- DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);

- DecodeTag->SOF_corr = DecodeTag->SOF_correlator[DecodeTag->SOF_last];

- DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;

- // initialize Decoder

- DecodeTag->posCount = 0;

- DecodeTag->bitCount = 0;

- DecodeTag->len = 0;

- DecodeTag->state = STATE_TAG_AWAIT_SOF_1;

- break;

- case STATE_TAG_AWAIT_SOF_1:

- // calculate the correlation in real time. Look at differences only.

- DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++];

- DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++];

- DecodeTag->SOF_last++;

- DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);

- DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last];

-

- // if correlation increases for 10 consecutive samples, we are close to maximum correlation

- if (DecodeTag->SOF_corr > DecodeTag->SOF_corr_prev + SUBCARRIER_DETECT_THRESHOLD) {

- DecodeTag->posCount++;

+static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *DecodeTag) {

+ switch (DecodeTag->state) {

+ case STATE_TAG_SOF_LOW:

+ // waiting for a rising edge

+ if (amplitude > NOISE_THRESHOLD + DecodeTag->previous_amplitude) {

+ if (DecodeTag->posCount > 10) {

+ DecodeTag->threshold_sof = amplitude - DecodeTag->previous_amplitude; // to be divided by 2

+ DecodeTag->threshold_half = 0;

+ DecodeTag->state = STATE_TAG_SOF_RISING_EDGE;

+ } else {

+ DecodeTag->posCount = 0;

+ }

} else {

- DecodeTag->posCount = 0;

+ DecodeTag->posCount++;

+ DecodeTag->previous_amplitude = amplitude;

}

+ break;

- if (DecodeTag->posCount == 10) { // correlation increased 10 times

- DecodeTag->state = STATE_TAG_AWAIT_SOF_2;

+ case STATE_TAG_SOF_RISING_EDGE:

+ if (amplitude > DecodeTag->threshold_sof + DecodeTag->previous_amplitude) { // edge still rising

+ if (amplitude > DecodeTag->threshold_sof + DecodeTag->threshold_sof) { // steeper edge, take this as time reference

+ DecodeTag->posCount = 1;

+ } else {

+ DecodeTag->posCount = 2;

+ }

+ DecodeTag->threshold_sof = (amplitude - DecodeTag->previous_amplitude) / 2;

+ } else {

+ DecodeTag->posCount = 2;

+ DecodeTag->threshold_sof = DecodeTag->threshold_sof/2;

}

+ // DecodeTag->posCount = 2;

+ DecodeTag->state = STATE_TAG_SOF_HIGH;

+ break;

- DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;

-

+ case STATE_TAG_SOF_HIGH:

+ // waiting for 10 times high. Take average over the last 8

+ if (amplitude > DecodeTag->threshold_sof) {

+ DecodeTag->posCount++;

+ if (DecodeTag->posCount > 2) {

+ DecodeTag->threshold_half += amplitude; // keep track of average high value

+ }

+ if (DecodeTag->posCount == 10) {

+ DecodeTag->threshold_half >>= 2; // (4 times 1/2 average)

+ DecodeTag->state = STATE_TAG_SOF_HIGH_END;

+ }

+ } else { // high phase was too short

+ DecodeTag->posCount = 1;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ }

break;

- case STATE_TAG_AWAIT_SOF_2:

- // calculate the correlation in real time. Look at differences only.

- DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++];

- DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++];

- DecodeTag->SOF_last++;

- DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1);

- DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);

- DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last];

-

- if (DecodeTag->SOF_corr >= DecodeTag->SOF_corr_prev) { // we are looking for the maximum correlation

- DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;

- } else {

- DecodeTag->lastBit = SOF_PART1; // detected 1st part of SOF

- DecodeTag->sum1 = DecodeTag->SOF_correlator[DecodeTag->SOF_last];

+ case STATE_TAG_SOF_HIGH_END:

+ // check for falling edge

+ if (DecodeTag->posCount == 13 && amplitude < DecodeTag->threshold_sof) {

+ DecodeTag->lastBit = SOF_PART1; // detected 1st part of SOF (12 samples low and 12 samples high)

+ DecodeTag->shiftReg = 0;

+ DecodeTag->bitCount = 0;

+ DecodeTag->len = 0;

+ DecodeTag->sum1 = amplitude;

DecodeTag->sum2 = 0;

DecodeTag->posCount = 2;

DecodeTag->state = STATE_TAG_RECEIVING_DATA;

DecodeTag->sum2 = 0;

DecodeTag->posCount = 2;

DecodeTag->state = STATE_TAG_RECEIVING_DATA;

+ // FpgaDisableTracing(); // DEBUGGING

+ // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d",

+ // amplitude,

+ // DecodeTag->threshold_sof,

+ // DecodeTag->threshold_half/4,

+ // DecodeTag->previous_amplitude); // DEBUGGING

LED_C_ON();

+ } else {

+ DecodeTag->posCount++;

+ if (DecodeTag->posCount > 13) { // high phase too long

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

}

-

break;

case STATE_TAG_RECEIVING_DATA:

break;

case STATE_TAG_RECEIVING_DATA:

+ // FpgaDisableTracing(); // DEBUGGING

+ // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d",

+ // amplitude,

+ // DecodeTag->threshold_sof,

+ // DecodeTag->threshold_half/4,

+ // DecodeTag->previous_amplitude); // DEBUGGING

if (DecodeTag->posCount == 1) {

DecodeTag->sum1 = 0;

DecodeTag->sum2 = 0;

}

if (DecodeTag->posCount == 1) {

DecodeTag->sum1 = 0;

DecodeTag->sum2 = 0;

}

-

if (DecodeTag->posCount <= 4) {

- DecodeTag->sum1 += AMPLITUDE(ci, cq);

+ DecodeTag->sum1 += amplitude;

} else {

- DecodeTag->sum2 += AMPLITUDE(ci, cq);

+ DecodeTag->sum2 += amplitude;

}

-

if (DecodeTag->posCount == 8) {

- int16_t corr_1 = (DecodeTag->sum2 - DecodeTag->sum1) / 4;

- int16_t corr_0 = (DecodeTag->sum1 - DecodeTag->sum2) / 4;

- int16_t corr_EOF = (DecodeTag->sum1 + DecodeTag->sum2) / 8;

- if (corr_EOF > corr_0 && corr_EOF > corr_1) {

- DecodeTag->state = STATE_TAG_AWAIT_EOF;

- } else if (corr_1 > corr_0) {

+ if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 > DecodeTag->threshold_half) { // modulation in both halves

+ if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF

+ DecodeTag->state = STATE_TAG_EOF;

+ } else {

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

+ } else if (DecodeTag->sum1 < DecodeTag->threshold_half && DecodeTag->sum2 > DecodeTag->threshold_half) { // modulation in second half

// logic 1

if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF

// logic 1

if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF

- DecodeTag->lastBit = SOF_PART2;

+ DecodeTag->lastBit = SOF_PART2; // SOF completed

} else {

DecodeTag->lastBit = LOGIC1;

DecodeTag->shiftReg >>= 1;

} else {

DecodeTag->lastBit = LOGIC1;

DecodeTag->shiftReg >>= 1;

if (DecodeTag->bitCount == 8) {

DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;

DecodeTag->len++;

if (DecodeTag->bitCount == 8) {

DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;

DecodeTag->len++;

+ // if (DecodeTag->shiftReg == 0x12 && DecodeTag->len == 1) FpgaDisableTracing(); // DEBUGGING

+ if (DecodeTag->len > DecodeTag->max_len) {

+ // buffer overflow, give up

+ LED_C_OFF();

+ return true;

+ }

DecodeTag->bitCount = 0;

DecodeTag->shiftReg = 0;

}

DecodeTag->bitCount = 0;

DecodeTag->shiftReg = 0;

}

- } else {

+ } else if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // modulation in first half

// logic 0

if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF

// logic 0

if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF

- DecodeTag->state = STATE_TAG_UNSYNCD;

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

LED_C_OFF();

} else {

DecodeTag->lastBit = LOGIC0;

LED_C_OFF();

} else {

DecodeTag->lastBit = LOGIC0;

if (DecodeTag->bitCount == 8) {

DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;

DecodeTag->len++;

if (DecodeTag->bitCount == 8) {

DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;

DecodeTag->len++;

+ // if (DecodeTag->shiftReg == 0x12 && DecodeTag->len == 1) FpgaDisableTracing(); // DEBUGGING

+ if (DecodeTag->len > DecodeTag->max_len) {

+ // buffer overflow, give up

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

DecodeTag->bitCount = 0;

DecodeTag->shiftReg = 0;

}

DecodeTag->bitCount = 0;

DecodeTag->shiftReg = 0;

}

+ } else { // no modulation

+ if (DecodeTag->lastBit == SOF_PART2) { // only SOF (this is OK for iClass)

+ LED_C_OFF();

+ return true;

+ } else {

+ DecodeTag->posCount = 0;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

}

DecodeTag->posCount = 0;

}

DecodeTag->posCount++;

break;

}

DecodeTag->posCount = 0;

}

DecodeTag->posCount++;

break;

- case STATE_TAG_AWAIT_EOF:

- if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF

- LED_C_OFF();

- return true;

+ case STATE_TAG_EOF:

+ if (DecodeTag->posCount == 1) {

+ DecodeTag->sum1 = 0;

+ DecodeTag->sum2 = 0;

+ }

+ if (DecodeTag->posCount <= 4) {

+ DecodeTag->sum1 += amplitude;

} else {

- DecodeTag->state = STATE_TAG_UNSYNCD;

- LED_C_OFF();

+ DecodeTag->sum2 += amplitude;

+ }

+ if (DecodeTag->posCount == 8) {

+ if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // modulation in first half

+ DecodeTag->posCount = 0;

+ DecodeTag->state = STATE_TAG_EOF_TAIL;

+ } else {

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

}

+ DecodeTag->posCount++;

break;

- default:

- DecodeTag->state = STATE_TAG_UNSYNCD;

- LED_C_OFF();

+ case STATE_TAG_EOF_TAIL:

+ if (DecodeTag->posCount == 1) {

+ DecodeTag->sum1 = 0;

+ DecodeTag->sum2 = 0;

+ }

+ if (DecodeTag->posCount <= 4) {

+ DecodeTag->sum1 += amplitude;

+ } else {

+ DecodeTag->sum2 += amplitude;

+ }

+ if (DecodeTag->posCount == 8) {

+ if (DecodeTag->sum1 < DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // no modulation in both halves

+ LED_C_OFF();

+ return true;

+ } else {

+ DecodeTag->posCount = 0;

+ DecodeTag->previous_amplitude = amplitude;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ LED_C_OFF();

+ }

+ DecodeTag->posCount++;

break;

}

break;

}

-static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data)

-{

+static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data, uint16_t max_len) {

+ DecodeTag->previous_amplitude = MAX_PREVIOUS_AMPLITUDE;

+ DecodeTag->posCount = 0;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

DecodeTag->output = data;

- DecodeTag->state = STATE_TAG_UNSYNCD;

+ DecodeTag->max_len = max_len;

}

+

+static void DecodeTagReset(DecodeTag_t *DecodeTag) {

+ DecodeTag->posCount = 0;

+ DecodeTag->state = STATE_TAG_SOF_LOW;

+ DecodeTag->previous_amplitude = MAX_PREVIOUS_AMPLITUDE;

+}

+

/*

* Receive and decode the tag response, also log to tracebuffer

*/

/*

* Receive and decode the tag response, also log to tracebuffer

*/

-static int GetIso15693AnswerFromTag(uint8_t* response, int timeout)

-{

- int maxBehindBy = 0;

- int lastRxCounter, samples = 0;

- int8_t ci, cq;

- bool gotFrame = false;

+int GetIso15693AnswerFromTag(uint8_t* response, uint16_t max_len, uint16_t timeout, uint32_t *eof_time) {

+

+ int samples = 0;

+ int ret = 0;

uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];

// the Decoder data structure

uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];

// the Decoder data structure

- DecodeTag_t DecodeTag;

- DecodeTagInit(&DecodeTag, response);

+ DecodeTag_t DecodeTag = { 0 };

+ DecodeTagInit(&DecodeTag, response, max_len);

// wait for last transfer to complete

while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));

// And put the FPGA in the appropriate mode

// wait for last transfer to complete

while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));

// And put the FPGA in the appropriate mode

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_SUBCARRIER_424_KHZ | FPGA_HF_READER_MODE_RECEIVE_AMPLITUDE);

// Setup and start DMA.

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);

FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);

+ uint32_t dma_start_time = 0;

uint16_t *upTo = dmaBuf;

- lastRxCounter = ISO15693_DMA_BUFFER_SIZE;

for(;;) {

- int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1);

- if(behindBy > maxBehindBy) {

- maxBehindBy = behindBy;

- }

+ uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1);

- if (behindBy < 1) continue;

+ if (behindBy == 0) continue;

- ci = (int8_t)(*upTo >> 8);

- cq = (int8_t)(*upTo & 0xff);

+ samples++;

+ if (samples == 1) {

+ // DMA has transferred the very first data

+ dma_start_time = GetCountSspClk() & 0xfffffff0;

+ }

+

+ uint16_t tagdata = *upTo++;

- upTo++;

- lastRxCounter--;

if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.

upTo = dmaBuf; // start reading the circular buffer from the beginning

if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.

upTo = dmaBuf; // start reading the circular buffer from the beginning

- lastRxCounter += ISO15693_DMA_BUFFER_SIZE;

+ if (behindBy > (9*ISO15693_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 = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers

}

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 = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers

}

- samples++;

- if (Handle15693SamplesFromTag(ci, cq, &DecodeTag)) {

- gotFrame = true;

+ if (Handle15693SamplesFromTag(tagdata, &DecodeTag)) {

+ *eof_time = dma_start_time + samples*16 - DELAY_TAG_TO_ARM; // end of EOF

+ if (DecodeTag.lastBit == SOF_PART2) {

+ *eof_time -= 8*16; // needed 8 additional samples to confirm single SOF (iCLASS)

+ }

+ if (DecodeTag.len > DecodeTag.max_len) {

+ ret = -2; // buffer overflow

+ }

break;

}

break;

}

- if(samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) {

- DecodeTag.len = 0;

+ if (samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) {

+ ret = -1; // timeout

break;

}

break;

}

FpgaDisableSscDma();

- if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d",

- maxBehindBy, samples, gotFrame, DecodeTag.state, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount);

+ if (DEBUG) Dbprintf("samples = %d, ret = %d, Decoder: state = %d, lastBit = %d, len = %d, bitCount = %d, posCount = %d",

+ samples, ret, DecodeTag.state, DecodeTag.lastBit, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount);

- if (tracing && DecodeTag.len > 0) {

- LogTrace(DecodeTag.output, DecodeTag.len, 0, 0, NULL, false);

+ if (ret < 0) {

+ return ret;

}

+ uint32_t sof_time = *eof_time

+ - DecodeTag.len * 8 * 8 * 16 // time for byte transfers

+ - 32 * 16 // time for SOF transfer

+ - (DecodeTag.lastBit != SOF_PART2?32*16:0); // time for EOF transfer

+

+ if (DEBUG) Dbprintf("timing: sof_time = %d, eof_time = %d", sof_time, *eof_time);

+

+ LogTrace_ISO15693(DecodeTag.output, DecodeTag.len, sof_time*4, *eof_time*4, NULL, false);

+

return DecodeTag.len;

}

return DecodeTag.len;

}

typedef struct DecodeReader {

enum {

STATE_READER_UNSYNCD,

typedef struct DecodeReader {

enum {

STATE_READER_UNSYNCD,

+ STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF,

STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF,

STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4,

STATE_READER_RECEIVE_DATA_1_OUT_OF_4,

STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF,

STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4,

STATE_READER_RECEIVE_DATA_1_OUT_OF_4,

- STATE_READER_RECEIVE_DATA_1_OUT_OF_256

+ STATE_READER_RECEIVE_DATA_1_OUT_OF_256,

+ STATE_READER_RECEIVE_JAMMING

} state;

enum {

CODING_1_OUT_OF_4,

} state;

enum {

CODING_1_OUT_OF_4,

int byteCount;

int byteCountMax;

int posCount;

int byteCount;

int byteCountMax;

int posCount;

- int sum1, sum2;

+ int sum1, sum2;

uint8_t *output;

+ uint8_t jam_search_len;

+ uint8_t *jam_search_string;

} DecodeReader_t;

-static int Handle15693SampleFromReader(uint8_t bit, DecodeReader_t* DecodeReader)

-{

- switch(DecodeReader->state) {

+static void DecodeReaderInit(DecodeReader_t* DecodeReader, uint8_t *data, uint16_t max_len, uint8_t jam_search_len, uint8_t *jam_search_string) {

+ DecodeReader->output = data;

+ DecodeReader->byteCountMax = max_len;

+ DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReader->byteCount = 0;

+ DecodeReader->bitCount = 0;

+ DecodeReader->posCount = 1;

+ DecodeReader->shiftReg = 0;

+ DecodeReader->jam_search_len = jam_search_len;

+ DecodeReader->jam_search_string = jam_search_string;

+}

+

+static void DecodeReaderReset(DecodeReader_t* DecodeReader) {

+ DecodeReader->state = STATE_READER_UNSYNCD;

+}

+

+static int inline __attribute__((always_inline)) Handle15693SampleFromReader(bool bit, DecodeReader_t *DecodeReader) {

+ switch (DecodeReader->state) {

case STATE_READER_UNSYNCD:

- if(!bit) {

+ // wait for unmodulated carrier

+ if (bit) {

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

+ }

+ break;

+

+ case STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF:

+ if (!bit) {

// we went low, so this could be the beginning of a SOF

- DecodeReader->state = STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF;

DecodeReader->posCount = 1;

+ DecodeReader->state = STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF;

}

break;

case STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF:

DecodeReader->posCount++;

}

break;

case STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF:

DecodeReader->posCount++;

- if(bit) { // detected rising edge

- if(DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5)

- DecodeReader->state = STATE_READER_UNSYNCD;

+ if (bit) { // detected rising edge

+ if (DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5)

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else { // SOF

DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF;

}

} else {

} else { // SOF

DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF;

}

} else {

- if(DecodeReader->posCount > 5) { // stayed low for too long

- DecodeReader->state = STATE_READER_UNSYNCD;

+ if (DecodeReader->posCount > 5) { // stayed low for too long

+ DecodeReaderReset(DecodeReader);

} else {

// do nothing, keep waiting

}

} else {

// do nothing, keep waiting

}

case STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF:

DecodeReader->posCount++;

case STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF:

DecodeReader->posCount++;

- if(!bit) { // detected a falling edge

+ if (!bit) { // detected a falling edge

if (DecodeReader->posCount < 20) { // falling edge too early (nominally expected at 21 earliest)

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

} else if (DecodeReader->posCount < 23) { // SOF for 1 out of 4 coding

DecodeReader->Coding = CODING_1_OUT_OF_4;

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

} else if (DecodeReader->posCount < 28) { // falling edge too early (nominally expected at 29 latest)

} else if (DecodeReader->posCount < 23) { // SOF for 1 out of 4 coding

DecodeReader->Coding = CODING_1_OUT_OF_4;

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

} else if (DecodeReader->posCount < 28) { // falling edge too early (nominally expected at 29 latest)

- DecodeReader->state = STATE_READER_UNSYNCD;

- } else { // SOF for 1 out of 4 coding

+ DecodeReaderReset(DecodeReader);

+ } else { // SOF for 1 out of 256 coding

DecodeReader->Coding = CODING_1_OUT_OF_256;

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

}

} else {

DecodeReader->Coding = CODING_1_OUT_OF_256;

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

}

} else {

- if(DecodeReader->posCount > 29) { // stayed high for too long

- DecodeReader->state = STATE_READER_UNSYNCD;

+ if (DecodeReader->posCount > 29) { // stayed high for too long

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

// do nothing, keep waiting

}

} else {

// do nothing, keep waiting

}

if (bit) { // detected rising edge

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount < 32) { // rising edge too early (nominally expected at 33)

if (bit) { // detected rising edge

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount < 32) { // rising edge too early (nominally expected at 33)

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

} else {

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25)

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25)

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

+ DecodeReader->posCount = 1;

DecodeReader->state = STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4;

}

} else {

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount > 34) { // signal stayed low for too long

DecodeReader->state = STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4;

}

} else {

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount > 34) { // signal stayed low for too long

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

} else {

// do nothing, keep waiting

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount > 26) { // signal stayed low for too long

} else {

// do nothing, keep waiting

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount > 26) { // signal stayed low for too long

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

} else {

// do nothing, keep waiting

}

} else {

// do nothing, keep waiting

}

case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4:

DecodeReader->posCount++;

if (bit) {

case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4:

DecodeReader->posCount++;

if (bit) {

- if (DecodeReader->posCount == 33) {

+ if (DecodeReader->posCount == 9) {

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

DecodeReader->byteCount = 0;

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

DecodeReader->byteCount = 0;

// do nothing, keep waiting

}

} else { // unexpected falling edge

// do nothing, keep waiting

}

} else { // unexpected falling edge

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

}

break;

case STATE_READER_RECEIVE_DATA_1_OUT_OF_4:

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

}

break;

case STATE_READER_RECEIVE_DATA_1_OUT_OF_4:

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

- DecodeReader->sum1 = bit;

+ DecodeReader->sum1 = bit?1:0;

} else if (DecodeReader->posCount <= 4) {

- DecodeReader->sum1 += bit;

+ if (bit) DecodeReader->sum1++;

} else if (DecodeReader->posCount == 5) {

- DecodeReader->sum2 = bit;

+ DecodeReader->sum2 = bit?1:0;

} else {

- DecodeReader->sum2 += bit;

+ if (bit) DecodeReader->sum2++;

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

- int corr10 = DecodeReader->sum1 - DecodeReader->sum2;

- int corr01 = DecodeReader->sum2 - DecodeReader->sum1;

- int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;

- if (corr01 > corr11 && corr01 > corr10) { // EOF

+ if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF

LED_B_OFF(); // Finished receiving

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

if (DecodeReader->byteCount != 0) {

return true;

}

if (DecodeReader->byteCount != 0) {

return true;

}

- }

- if (corr10 > corr11) { // detected a 2bit position

+ } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected a 2bit position

DecodeReader->shiftReg >>= 2;

DecodeReader->shiftReg |= (DecodeReader->bitCount << 6);

}

DecodeReader->shiftReg >>= 2;

DecodeReader->shiftReg |= (DecodeReader->bitCount << 6);

}

if (DecodeReader->byteCount > DecodeReader->byteCountMax) {

// buffer overflow, give up

LED_B_OFF();

if (DecodeReader->byteCount > DecodeReader->byteCountMax) {

// buffer overflow, give up

LED_B_OFF();

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

}

DecodeReader->bitCount = 0;

}

DecodeReader->bitCount = 0;

+ DecodeReader->shiftReg = 0;

+ if (DecodeReader->byteCount == DecodeReader->jam_search_len) {

+ if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {

+ LED_D_ON();

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM);

+ DecodeReader->state = STATE_READER_RECEIVE_JAMMING;

+ }

} else {

DecodeReader->bitCount++;

}

} else {

DecodeReader->bitCount++;

}

case STATE_READER_RECEIVE_DATA_1_OUT_OF_256:

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

case STATE_READER_RECEIVE_DATA_1_OUT_OF_256:

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

- DecodeReader->sum1 = bit;

+ DecodeReader->sum1 = bit?1:0;

} else if (DecodeReader->posCount <= 4) {

- DecodeReader->sum1 += bit;

+ if (bit) DecodeReader->sum1++;

} else if (DecodeReader->posCount == 5) {

- DecodeReader->sum2 = bit;

- } else {

- DecodeReader->sum2 += bit;

+ DecodeReader->sum2 = bit?1:0;

+ } else if (bit) {

+ DecodeReader->sum2++;

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

- int corr10 = DecodeReader->sum1 - DecodeReader->sum2;

- int corr01 = DecodeReader->sum2 - DecodeReader->sum1;

- int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;

- if (corr01 > corr11 && corr01 > corr10) { // EOF

+ if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF

LED_B_OFF(); // Finished receiving

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

if (DecodeReader->byteCount != 0) {

return true;

}

if (DecodeReader->byteCount != 0) {

return true;

}

- }

- if (corr10 > corr11) { // detected the bit position

+ } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected the bit position

DecodeReader->shiftReg = DecodeReader->bitCount;

}

if (DecodeReader->bitCount == 255) { // we have a full byte

DecodeReader->shiftReg = DecodeReader->bitCount;

}

if (DecodeReader->bitCount == 255) { // we have a full byte

if (DecodeReader->byteCount > DecodeReader->byteCountMax) {

// buffer overflow, give up

LED_B_OFF();

if (DecodeReader->byteCount > DecodeReader->byteCountMax) {

// buffer overflow, give up

LED_B_OFF();

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

+ }

+ if (DecodeReader->byteCount == DecodeReader->jam_search_len) {

+ if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {

+ LED_D_ON();

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM);

+ DecodeReader->state = STATE_READER_RECEIVE_JAMMING;

+ }

}

DecodeReader->bitCount++;

}

break;

}

DecodeReader->bitCount++;

}

break;

+ case STATE_READER_RECEIVE_JAMMING:

+ DecodeReader->posCount++;

+ if (DecodeReader->Coding == CODING_1_OUT_OF_4) {

+ if (DecodeReader->posCount == 7*16) { // 7 bits jammed

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming

+ // FpgaDisableTracing();

+ LED_D_OFF();

+ } else if (DecodeReader->posCount == 8*16) {

+ DecodeReader->posCount = 0;

+ DecodeReader->output[DecodeReader->byteCount++] = 0x00;

+ DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4;

+ }

+ } else {

+ if (DecodeReader->posCount == 7*256) { // 7 bits jammend

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming

+ LED_D_OFF();

+ } else if (DecodeReader->posCount == 8*256) {

+ DecodeReader->posCount = 0;

+ DecodeReader->output[DecodeReader->byteCount++] = 0x00;

+ DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256;

+ }

+ break;

+

default:

LED_B_OFF();

default:

LED_B_OFF();

- DecodeReader->state = STATE_READER_UNSYNCD;

+ DecodeReaderReset(DecodeReader);

break;

}

break;

}

-static void DecodeReaderInit(uint8_t *data, uint16_t max_len, DecodeReader_t* DecodeReader)

-{

- DecodeReader->output = data;

- DecodeReader->byteCountMax = max_len;

- DecodeReader->state = STATE_READER_UNSYNCD;

- DecodeReader->byteCount = 0;

- DecodeReader->bitCount = 0;

- DecodeReader->posCount = 0;

- DecodeReader->shiftReg = 0;

-}

-

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

// Receive a command (from the reader to us, where we are the simulated tag),

// and store it in the given buffer, up to the given maximum length. Keeps

// spinning, waiting for a well-framed command, until either we get one

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

// Receive a command (from the reader to us, where we are the simulated tag),

// and store it in the given buffer, up to the given maximum length. Keeps

// spinning, waiting for a well-framed command, until either we get one

-// (returns true) or someone presses the pushbutton on the board (false).

+// (returns len) or someone presses the pushbutton on the board (returns -1).

//

// Assume that we're called with the SSC (to the FPGA) and ADC path set

// correctly.

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

//

// Assume that we're called with the SSC (to the FPGA) and ADC path set

// correctly.

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

-static int GetIso15693CommandFromReader(uint8_t *received, size_t max_len, uint32_t *eof_time)

-{

- int maxBehindBy = 0;

- int lastRxCounter, samples = 0;

+int GetIso15693CommandFromReader(uint8_t *received, size_t max_len, uint32_t *eof_time) {

+ int samples = 0;

bool gotFrame = false;

uint8_t b;

uint8_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];

// the decoder data structure

bool gotFrame = false;

uint8_t b;

uint8_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];

// the decoder data structure

- DecodeReader_t DecodeReader;

- DecodeReaderInit(received, max_len, &DecodeReader);

+ DecodeReader_t DecodeReader = {0};

+ DecodeReaderInit(&DecodeReader, received, max_len, 0, NULL);

// wait for last transfer to complete

while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));

// wait for last transfer to complete

while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));

(void) temp;

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

(void) temp;

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

- uint32_t bit_time = GetCountSspClk() & 0xfffffff8;

+ uint32_t dma_start_time = GetCountSspClk() & 0xfffffff8;

// Setup and start DMA.

FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE);

uint8_t *upTo = dmaBuf;

// Setup and start DMA.

FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE);

uint8_t *upTo = dmaBuf;

- lastRxCounter = ISO15693_DMA_BUFFER_SIZE;

- for(;;) {

- int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1);

- if(behindBy > maxBehindBy) {

- maxBehindBy = behindBy;

- }

+ for (;;) {

+ uint16_t behindBy = ((uint8_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1);

- if (behindBy < 1) continue;

+ if (behindBy == 0) continue;

b = *upTo++;

- lastRxCounter--;

- if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.

+ if (upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.

upTo = dmaBuf; // start reading the circular buffer from the beginning

- lastRxCounter += ISO15693_DMA_BUFFER_SIZE;

+ if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {

+ Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy);

+ 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

}

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

for (int i = 7; i >= 0; i--) {

if (Handle15693SampleFromReader((b >> i) & 0x01, &DecodeReader)) {

for (int i = 7; i >= 0; i--) {

if (Handle15693SampleFromReader((b >> i) & 0x01, &DecodeReader)) {

- *eof_time = bit_time + samples - DELAY_READER_TO_ARM; // end of EOF

+ *eof_time = dma_start_time + samples - DELAY_READER_TO_ARM; // end of EOF

gotFrame = true;

break;

}

gotFrame = true;

break;

}

if (BUTTON_PRESS()) {

}

if (BUTTON_PRESS()) {

- DecodeReader.byteCount = 0;

+ DecodeReader.byteCount = -1;

break;

}

WDT_HIT();

}

break;

}

WDT_HIT();

}

-

FpgaDisableSscDma();

- if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d",

- maxBehindBy, samples, gotFrame, DecodeReader.state, DecodeReader.byteCount, DecodeReader.bitCount, DecodeReader.posCount);

+ if (DEBUG) Dbprintf("samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d",

+ samples, gotFrame, DecodeReader.state, DecodeReader.byteCount, DecodeReader.bitCount, DecodeReader.posCount);

- if (tracing && DecodeReader.byteCount > 0) {

- LogTrace(DecodeReader.output, DecodeReader.byteCount, 0, 0, NULL, true);

+ if (DecodeReader.byteCount > 0) {

+ uint32_t sof_time = *eof_time

+ - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128:2048) // time for byte transfers

+ - 32 // time for SOF transfer

+ - 16; // time for EOF transfer

+ LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, sof_time*32, *eof_time*32, NULL, true);

}

return DecodeReader.byteCount;

}

return DecodeReader.byteCount;

}

-static void BuildIdentifyRequest(void);

+// Construct an identify (Inventory) request, which is the first

+// thing that you must send to a tag to get a response.

+static void BuildIdentifyRequest(uint8_t *cmd) {

+ uint16_t crc;

+ // one sub-carrier, inventory, 1 slot, fast rate

+ cmd[0] = ISO15693_REQ_INVENTORY | ISO15693_REQINV_SLOT1 | ISO15693_REQ_DATARATE_HIGH;

+ // inventory command code

+ cmd[1] = 0x01;

+ // no mask

+ cmd[2] = 0x00;

+ //Now the CRC

+ crc = Iso15693Crc(cmd, 3);

+ cmd[3] = crc & 0xff;

+ cmd[4] = crc >> 8;

+}

+

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

// Start to read an ISO 15693 tag. We send an identify request, then wait

// for the response. The response is not demodulated, just left in the buffer

// so that it can be downloaded to a PC and processed there.

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

// Start to read an ISO 15693 tag. We send an identify request, then wait

// for the response. The response is not demodulated, just left in the buffer

// so that it can be downloaded to a PC and processed there.

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

-void AcquireRawAdcSamplesIso15693(void)

-{

- LEDsoff();

+void AcquireRawAdcSamplesIso15693(void) {

LED_A_ON();

uint8_t *dest = BigBuf_get_addr();

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

LED_A_ON();

uint8_t *dest = BigBuf_get_addr();

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

- BuildIdentifyRequest();

-

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER);

+ LED_D_ON();

+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);

SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

+ uint8_t cmd[5];

+ BuildIdentifyRequest(cmd);

+ CodeIso15693AsReader(cmd, sizeof(cmd));

+

// Give the tags time to energize

- LED_D_ON();

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

SpinDelay(100);

// Now send the command

SpinDelay(100);

// Now send the command

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);

-

- LED_B_ON();

- for(int c = 0; c < ToSendMax; ) {

- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {

- AT91C_BASE_SSC->SSC_THR = ~ToSend[c];

- c++;

- }

- WDT_HIT();

- }

- LED_B_OFF();

+ uint32_t start_time = 0;

+ TransmitTo15693Tag(ToSend, ToSendMax, &start_time);

// wait for last transfer to complete

- while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));

+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)) ;

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_SUBCARRIER_424_KHZ | FPGA_HF_READER_MODE_RECEIVE_AMPLITUDE);

for(int c = 0; c < 4000; ) {

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

for(int c = 0; c < 4000; ) {

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

- uint16_t iq = AT91C_BASE_SSC->SSC_RHR;

- // The samples are correlations against I and Q versions of the

- // tone that the tag AM-modulates. We just want power,

- // so abs(I) + abs(Q) is close to what we want.

- int8_t i = (int8_t)(iq >> 8);

- int8_t q = (int8_t)(iq & 0xff);

- uint8_t r = AMPLITUDE(i, q);

- dest[c++] = r;

+ uint16_t r = AT91C_BASE_SSC->SSC_RHR;

+ dest[c++] = r >> 5;

}

-// TODO: there is no trigger condition. The 14000 samples represent a time frame of 66ms.

-// It is unlikely that we get something meaningful.

-// TODO: Currently we only record tag answers. Add tracing of reader commands.

-// TODO: would we get something at all? The carrier is switched on...

-void RecordRawAdcSamplesIso15693(void)

-{

- LEDsoff();

- LED_A_ON();

+void SnoopIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {

- uint8_t *dest = BigBuf_get_addr();

+ LED_A_ON();

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

- // Setup SSC

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

- // Start from off (no field generated)

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

- SpinDelay(200);

+ clear_trace();

+ set_tracing(true);

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

+ uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];

+

+ // Count of samples received so far, so that we can include timing

+ // information in the trace buffer.

+ int samples = 0;

+

+ DecodeTag_t DecodeTag = {0};

+ uint8_t response[ISO15693_MAX_RESPONSE_LENGTH];

+ DecodeTagInit(&DecodeTag, response, sizeof(response));

+

+ DecodeReader_t DecodeReader = {0};

+ uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH];

+ DecodeReaderInit(&DecodeReader, cmd, sizeof(cmd), jam_search_len, jam_search_string);

+

+ // Print some debug information about the buffer sizes

+ if (DEBUG) {

+ Dbprintf("Snooping buffers initialized:");

+ Dbprintf(" Trace: %i bytes", BigBuf_max_traceLen());

+ Dbprintf(" Reader -> tag: %i bytes", ISO15693_MAX_COMMAND_LENGTH);

+ Dbprintf(" tag -> Reader: %i bytes", ISO15693_MAX_RESPONSE_LENGTH);

+ Dbprintf(" DMA: %i bytes", ISO15693_DMA_BUFFER_SIZE * sizeof(uint16_t));

+ }

+ Dbprintf("Snoop started. Press PM3 Button to stop.");

+

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE);

+ LED_D_OFF();

SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);

+ StartCountSspClk();

+ FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);

- SpinDelay(100);

+ bool TagIsActive = false;

+ bool ReaderIsActive = false;

+ bool ExpectTagAnswer = false;

+ uint32_t dma_start_time = 0;

+ uint16_t *upTo = dmaBuf;

- LED_D_ON();

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ uint16_t max_behindBy = 0;

+

+ // And now we loop, receiving samples.

+ for(;;) {

+ uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1);

+ if (behindBy > max_behindBy) {

+ max_behindBy = behindBy;

+ }

+

+ if (behindBy == 0) continue;

- for(int c = 0; c < 14000;) {

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

- uint16_t iq = AT91C_BASE_SSC->SSC_RHR;

- // The samples are correlations against I and Q versions of the

- // tone that the tag AM-modulates. We just want power,

- // so abs(I) + abs(Q) is close to what we want.

- int8_t i = (int8_t)(iq >> 8);

- int8_t q = (int8_t)(iq & 0xff);

- uint8_t r = AMPLITUDE(i, q);

- dest[c++] = r;

+ samples++;

+ if (samples == 1) {

+ // DMA has transferred the very first data

+ dma_start_time = GetCountSspClk() & 0xfffffff0;

+ }

+

+ uint16_t snoopdata = *upTo++;

+

+ if (upTo >= dmaBuf + ISO15693_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*ISO15693_DMA_BUFFER_SIZE/10)) {

+ // FpgaDisableTracing();

+ Dbprintf("About to blow circular buffer - aborted! behindBy=%d, samples=%d", behindBy, samples);

+ 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 = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers

+ WDT_HIT();

+ if (BUTTON_PRESS()) {

+ DbpString("Snoop stopped.");

+ break;

+ }

+

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

+ if (Handle15693SampleFromReader(snoopdata & 0x02, &DecodeReader)) {

+ // FpgaDisableSscDma();

+ uint32_t eof_time = dma_start_time + samples*16 + 8 - DELAY_READER_TO_ARM_SNOOP; // end of EOF

+ if (DecodeReader.byteCount > 0) {

+ uint32_t sof_time = eof_time

+ - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers

+ - 32*16 // time for SOF transfer

+ - 16*16; // time for EOF transfer

+ LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true);

+ }

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

+ DecodeReaderReset(&DecodeReader);

+ /* And also reset the demod code, which might have been */

+ /* false-triggered by the commands from the reader. */

+ DecodeTagReset(&DecodeTag);

+ ReaderIsActive = false;

+ ExpectTagAnswer = true;

+ // upTo = dmaBuf;

+ // samples = 0;

+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);

+ // continue;

+ } else if (Handle15693SampleFromReader(snoopdata & 0x01, &DecodeReader)) {

+ // FpgaDisableSscDma();

+ uint32_t eof_time = dma_start_time + samples*16 + 16 - DELAY_READER_TO_ARM_SNOOP; // end of EOF

+ if (DecodeReader.byteCount > 0) {

+ uint32_t sof_time = eof_time

+ - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers

+ - 32*16 // time for SOF transfer

+ - 16*16; // time for EOF transfer

+ LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true);

+ }

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

+ DecodeReaderReset(&DecodeReader);

+ /* And also reset the demod code, which might have been */

+ /* false-triggered by the commands from the reader. */

+ DecodeTagReset(&DecodeTag);

+ ReaderIsActive = false;

+ ExpectTagAnswer = true;

+ // upTo = dmaBuf;

+ // samples = 0;

+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);

+ // continue;

+ } else {

+ ReaderIsActive = (DecodeReader.state >= STATE_READER_RECEIVE_DATA_1_OUT_OF_4);

+ }

}

+

+ if (!ReaderIsActive && ExpectTagAnswer) { // no need to try decoding tag data if the reader is currently sending or no answer expected yet

+ if (Handle15693SamplesFromTag(snoopdata >> 2, &DecodeTag)) {

+ // FpgaDisableSscDma();

+ uint32_t eof_time = dma_start_time + samples*16 - DELAY_TAG_TO_ARM_SNOOP; // end of EOF

+ if (DecodeTag.lastBit == SOF_PART2) {

+ eof_time -= 8*16; // needed 8 additional samples to confirm single SOF (iCLASS)

+ }

+ uint32_t sof_time = eof_time

+ - DecodeTag.len * 8 * 8 * 16 // time for byte transfers

+ - 32 * 16 // time for SOF transfer

+ - (DecodeTag.lastBit != SOF_PART2?32*16:0); // time for EOF transfer

+ LogTrace_ISO15693(DecodeTag.output, DecodeTag.len, sof_time*4, eof_time*4, NULL, false);

+ // And ready to receive another response.

+ DecodeTagReset(&DecodeTag);

+ DecodeReaderReset(&DecodeReader);

+ ExpectTagAnswer = false;

+ TagIsActive = false;

+ // upTo = dmaBuf;

+ // samples = 0;

+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);

+ // continue;

+ } else {

+ TagIsActive = (DecodeTag.state >= STATE_TAG_RECEIVING_DATA);

+ }

+

}

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

- LED_D_OFF();

- Dbprintf("finished recording");

- LED_A_OFF();

+ FpgaDisableSscDma();

+

+ DbpString("Snoop statistics:");

+ Dbprintf(" ExpectTagAnswer: %d, TagIsActive: %d, ReaderIsActive: %d", ExpectTagAnswer, TagIsActive, ReaderIsActive);

+ Dbprintf(" DecodeTag State: %d", DecodeTag.state);

+ Dbprintf(" DecodeTag byteCnt: %d", DecodeTag.len);

+ Dbprintf(" DecodeTag posCount: %d", DecodeTag.posCount);

+ Dbprintf(" DecodeReader State: %d", DecodeReader.state);

+ Dbprintf(" DecodeReader byteCnt: %d", DecodeReader.byteCount);

+ Dbprintf(" DecodeReader posCount: %d", DecodeReader.posCount);

+ Dbprintf(" Trace length: %d", BigBuf_get_traceLen());

+ Dbprintf(" Max behindBy: %d", max_behindBy);

}

// Initialize the proxmark as iso15k reader

}

// Initialize the proxmark as iso15k reader

-// (this might produces glitches that confuse some tags

-static void Iso15693InitReader() {

+void Iso15693InitReader(void) {

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

- // Setup SSC

- // FpgaSetupSsc();

- // Start from off (no field generated)

- LED_D_OFF();

+ // switch field off and wait until tag resets

FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ LED_D_OFF();

SpinDelay(10);

+ // switch field on

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER);

+ LED_D_ON();

+

+ // initialize SSC and select proper AD input

+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);

SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

- // Give the tags time to energize

- LED_D_ON();

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ // give tags some time to energize

SpinDelay(250);

}

SpinDelay(250);

}

// This section basically contains transmission and receiving of bits

///////////////////////////////////////////////////////////////////////

// This section basically contains transmission and receiving of bits

///////////////////////////////////////////////////////////////////////

-// Encode (into the ToSend buffers) an identify request, which is the first

-// thing that you must send to a tag to get a response.

-static void BuildIdentifyRequest(void)

-{

- uint8_t cmd[5];

-

- uint16_t crc;

- // one sub-carrier, inventory, 1 slot, fast rate

- // AFI is at bit 5 (1<<4) when doing an INVENTORY

- cmd[0] = (1 << 2) | (1 << 5) | (1 << 1);

- // inventory command code

- cmd[1] = 0x01;

- // no mask

- cmd[2] = 0x00;

- //Now the CRC

- crc = Crc(cmd, 3);

- cmd[3] = crc & 0xff;

- cmd[4] = crc >> 8;

-

- CodeIso15693AsReader(cmd, sizeof(cmd));

-}

// uid is in transmission order (which is reverse of display order)

-static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber )

-{

- uint8_t cmd[13];

-

+static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber, uint8_t *cmd) {

uint16_t crc;

- // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block

- // followed by teh block data

- // one sub-carrier, inventory, 1 slot, fast rate

- cmd[0] = (1 << 6)| (1 << 5) | (1 << 1); // no SELECT bit, ADDR bit, OPTION bit

+ // If we set the Option_Flag in this request, the VICC will respond with the security status of the block

+ // followed by the block data

+ cmd[0] = ISO15693_REQ_OPTION | ISO15693_REQ_ADDRESS | ISO15693_REQ_DATARATE_HIGH;

// READ BLOCK command code

- cmd[1] = 0x20;

+ cmd[1] = ISO15693_READBLOCK;

// UID may be optionally specified here

// 64-bit UID

cmd[2] = uid[0];

// UID may be optionally specified here

// 64-bit UID

cmd[2] = uid[0];

cmd[8] = uid[6];

cmd[9] = uid[7]; // 0xe0; // always e0 (not exactly unique)

// Block number to read

cmd[8] = uid[6];

cmd[9] = uid[7]; // 0xe0; // always e0 (not exactly unique)

// Block number to read

- cmd[10] = blockNumber;//0x00;

+ cmd[10] = blockNumber;

//Now the CRC

- crc = Crc(cmd, 11); // the crc needs to be calculated over 11 bytes

+ crc = Iso15693Crc(cmd, 11); // the crc needs to be calculated over 11 bytes

cmd[11] = crc & 0xff;

cmd[12] = crc >> 8;

cmd[11] = crc & 0xff;

cmd[12] = crc >> 8;

- CodeIso15693AsReader(cmd, sizeof(cmd));

}

// Now the VICC>VCD responses when we are simulating a tag

}

// Now the VICC>VCD responses when we are simulating a tag

-static void BuildInventoryResponse(uint8_t *uid)

-{

+static void BuildInventoryResponse(uint8_t *uid) {

uint8_t cmd[12];

uint16_t crc;

uint8_t cmd[12];

uint16_t crc;

cmd[8] = uid[1]; //0x05;

cmd[9] = uid[0]; //0xe0;

//Now the CRC

cmd[8] = uid[1]; //0x05;

cmd[9] = uid[0]; //0xe0;

//Now the CRC

- crc = Crc(cmd, 10);

+ crc = Iso15693Crc(cmd, 10);

cmd[10] = crc & 0xff;

cmd[11] = crc >> 8;

cmd[10] = crc & 0xff;

cmd[11] = crc >> 8;

}

// Universal Method for sending to and recv bytes from a tag

}

// Universal Method for sending to and recv bytes from a tag

-// init ... should we initialize the reader?

-// speed ... 0 low speed, 1 hi speed

-// **recv will return you a pointer to the received data

-// If you do not need the answer use NULL for *recv[]

-// return: lenght of received data

-int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t **recv) {

-

- LED_A_ON();

- LED_B_OFF();

- LED_C_OFF();

-

- if (init) Iso15693InitReader();

+// init ... should we initialize the reader?

+// speed ... 0 low speed, 1 hi speed

+// *recv will contain the tag's answer

+// return: length of received data, or -1 for timeout

+int SendDataTag(uint8_t *send, int sendlen, bool init, bool speed_fast, uint8_t *recv, uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time) {

+

+ if (init) {

+ Iso15693InitReader();

+ StartCountSspClk();

+ }

- int answerLen=0;

- uint8_t *answer = BigBuf_get_addr() + 4000;

- if (recv != NULL) memset(answer, 0, 100);

+ int answerLen = 0;

- if (!speed) {

- // low speed (1 out of 256)

- CodeIso15693AsReader256(send, sendlen);

- } else {

+ if (speed_fast) {

// high speed (1 out of 4)

CodeIso15693AsReader(send, sendlen);

// high speed (1 out of 4)

CodeIso15693AsReader(send, sendlen);

+ } else {

+ // low speed (1 out of 256)

+ CodeIso15693AsReader256(send, sendlen);

}

- TransmitTo15693Tag(ToSend,ToSendMax);

+ TransmitTo15693Tag(ToSend, ToSendMax, &start_time);

+ uint32_t end_time = start_time + 32*(8*ToSendMax-4); // substract the 4 padding bits after EOF

+ LogTrace_ISO15693(send, sendlen, start_time*4, end_time*4, NULL, true);

+

// Now wait for a response

- if (recv!=NULL) {

- answerLen = GetIso15693AnswerFromTag(answer, 100);

- *recv=answer;

+ if (recv != NULL) {

+ answerLen = GetIso15693AnswerFromTag(recv, max_recv_len, timeout, eof_time);

}

- LED_A_OFF();

+ return answerLen;

+}

+

+int SendDataTagEOF(uint8_t *recv, uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time) {

+

+ int answerLen = 0;

+

+ CodeIso15693AsReaderEOF();

+

+ TransmitTo15693Tag(ToSend, ToSendMax, &start_time);

+ uint32_t end_time = start_time + 32*(8*ToSendMax-4); // substract the 4 padding bits after EOF

+ LogTrace_ISO15693(NULL, 0, start_time*4, end_time*4, NULL, true);

+

+ // Now wait for a response

+ if (recv != NULL) {

+ answerLen = GetIso15693AnswerFromTag(recv, max_recv_len, timeout, eof_time);

+ }

return answerLen;

}

return answerLen;

}

char status[DBD15STATLEN+1]={0};

uint16_t crc;

char status[DBD15STATLEN+1]={0};

uint16_t crc;

- if (len>3) {

- if (d[0]&(1<<3))

- strncat(status,"ProtExt ",DBD15STATLEN);

- if (d[0]&1) {

+ if (len > 3) {

+ if (d[0] & ISO15693_RES_EXT)

+ strncat(status,"ProtExt ", DBD15STATLEN);

+ if (d[0] & ISO15693_RES_ERROR) {

// error

- strncat(status,"Error ",DBD15STATLEN);

+ strncat(status,"Error ", DBD15STATLEN);

switch (d[1]) {

case 0x01:

switch (d[1]) {

case 0x01:

- strncat(status,"01:notSupp",DBD15STATLEN);

+ strncat(status,"01:notSupp", DBD15STATLEN);

break;

case 0x02:

break;

case 0x02:

- strncat(status,"02:notRecog",DBD15STATLEN);

+ strncat(status,"02:notRecog", DBD15STATLEN);

break;

case 0x03:

break;

case 0x03:

- strncat(status,"03:optNotSupp",DBD15STATLEN);

+ strncat(status,"03:optNotSupp", DBD15STATLEN);

break;

case 0x0f:

break;

case 0x0f:

- strncat(status,"0f:noInfo",DBD15STATLEN);

+ strncat(status,"0f:noInfo", DBD15STATLEN);

break;

case 0x10:

break;

case 0x10:

- strncat(status,"10:dontExist",DBD15STATLEN);

+ strncat(status,"10:doesn'tExist", DBD15STATLEN);

break;

case 0x11:

break;

case 0x11:

- strncat(status,"11:lockAgain",DBD15STATLEN);

+ strncat(status,"11:lockAgain", DBD15STATLEN);

break;

case 0x12:

break;

case 0x12:

- strncat(status,"12:locked",DBD15STATLEN);

+ strncat(status,"12:locked", DBD15STATLEN);

break;

case 0x13:

break;

case 0x13:

- strncat(status,"13:progErr",DBD15STATLEN);

+ strncat(status,"13:progErr", DBD15STATLEN);

break;

case 0x14:

break;

case 0x14:

- strncat(status,"14:lockErr",DBD15STATLEN);

+ strncat(status,"14:lockErr", DBD15STATLEN);

break;

default:

break;

default:

- strncat(status,"unknownErr",DBD15STATLEN);

+ strncat(status,"unknownErr", DBD15STATLEN);

}

- strncat(status," ",DBD15STATLEN);

+ strncat(status," ", DBD15STATLEN);

} else {

- strncat(status,"NoErr ",DBD15STATLEN);

+ strncat(status,"NoErr ", DBD15STATLEN);

}

- crc=Crc(d,len-2);

+ crc=Iso15693Crc(d,len-2);

if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) )

strncat(status,"CrcOK",DBD15STATLEN);

else

if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) )

strncat(status,"CrcOK",DBD15STATLEN);

else

return;

}

return;

}

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

-// Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector

-// all demodulation performed in arm rather than host. - greg

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

-void ReaderIso15693(uint32_t parameter)

-{

- LEDsoff();

- LED_A_ON();

- int answerLen1 = 0;

- uint8_t TagUID[8] = {0x00};

-

- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

-

- uint8_t *answer1 = BigBuf_get_addr() + 4000;

- memset(answer1, 0x00, 200);

+//---------------------------------------------------------------------------------------

+// Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector.

+// all demodulation performed in arm rather than host. - greg

+//---------------------------------------------------------------------------------------

+void ReaderIso15693(uint32_t parameter) {

- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

- // Setup SSC

- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

+ LED_A_ON();

- // Start from off (no field generated)

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

- SpinDelay(200);

+ set_tracing(true);

- // Give the tags time to energize

- LED_D_ON();

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);

- SpinDelay(200);

+ uint8_t TagUID[8] = {0x00};

+ uint8_t answer[ISO15693_MAX_RESPONSE_LENGTH];

// FIRST WE RUN AN INVENTORY TO GET THE TAG UID

// THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME

// Now send the IDENTIFY command

// FIRST WE RUN AN INVENTORY TO GET THE TAG UID

// THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME

// Now send the IDENTIFY command

- BuildIdentifyRequest();

-

- TransmitTo15693Tag(ToSend,ToSendMax);

-

- // Now wait for a response

- answerLen1 = GetIso15693AnswerFromTag(answer1, 100) ;

-

- if (answerLen1 >=12) // we should do a better check than this

- {

- TagUID[0] = answer1[2];

- TagUID[1] = answer1[3];

- TagUID[2] = answer1[4];

- TagUID[3] = answer1[5];

- TagUID[4] = answer1[6];

- TagUID[5] = answer1[7];

- TagUID[6] = answer1[8]; // IC Manufacturer code

- TagUID[7] = answer1[9]; // always E0

-

+ uint8_t cmd[5];

+ BuildIdentifyRequest(cmd);

+ uint32_t start_time = 0;

+ uint32_t eof_time;

+ int answerLen = SendDataTag(cmd, sizeof(cmd), true, true, answer, sizeof(answer), start_time, ISO15693_READER_TIMEOUT, &eof_time);

+ start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER;

+

+ if (answerLen >= 12) { // we should do a better check than this

+ TagUID[0] = answer[2];

+ TagUID[1] = answer[3];

+ TagUID[2] = answer[4];

+ TagUID[3] = answer[5];

+ TagUID[4] = answer[6];

+ TagUID[5] = answer[7];

+ TagUID[6] = answer[8]; // IC Manufacturer code

+ TagUID[7] = answer[9]; // always E0

}

- Dbprintf("%d octets read from IDENTIFY request:", answerLen1);

- DbdecodeIso15693Answer(answerLen1, answer1);

- Dbhexdump(answerLen1, answer1, false);

+ Dbprintf("%d octets read from IDENTIFY request:", answerLen);

+ DbdecodeIso15693Answer(answerLen, answer);

+ Dbhexdump(answerLen, answer, false);

// UID is reverse

- if (answerLen1 >= 12)

+ if (answerLen >= 12)

Dbprintf("UID = %02hX%02hX%02hX%02hX%02hX%02hX%02hX%02hX",

TagUID[7],TagUID[6],TagUID[5],TagUID[4],

TagUID[3],TagUID[2],TagUID[1],TagUID[0]);

Dbprintf("UID = %02hX%02hX%02hX%02hX%02hX%02hX%02hX%02hX",

TagUID[7],TagUID[6],TagUID[5],TagUID[4],

TagUID[3],TagUID[2],TagUID[1],TagUID[0]);

-

- // Dbprintf("%d octets read from SELECT request:", answerLen2);

- // DbdecodeIso15693Answer(answerLen2,answer2);

- // Dbhexdump(answerLen2,answer2,true);

-

- // Dbprintf("%d octets read from XXX request:", answerLen3);

- // DbdecodeIso15693Answer(answerLen3,answer3);

- // Dbhexdump(answerLen3,answer3,true);

-

// read all pages

- if (answerLen1 >= 12 && DEBUG) {

- uint8_t *answer2 = BigBuf_get_addr() + 4100;

- int i = 0;

- while (i < 32) { // sanity check, assume max 32 pages

- BuildReadBlockRequest(TagUID, i);

- TransmitTo15693Tag(ToSend, ToSendMax);

- int answerLen2 = GetIso15693AnswerFromTag(answer2, 100);

- if (answerLen2 > 0) {

- Dbprintf("READ SINGLE BLOCK %d returned %d octets:", i, answerLen2);

- DbdecodeIso15693Answer(answerLen2, answer2);

- Dbhexdump(answerLen2, answer2, false);

- if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr

+ if (answerLen >= 12 && DEBUG) {

+ for (int i = 0; i < 32; i++) { // sanity check, assume max 32 pages

+ uint8_t cmd[13];

+ BuildReadBlockRequest(TagUID, i, cmd);

+ answerLen = SendDataTag(cmd, sizeof(cmd), false, true, answer, sizeof(answer), start_time, ISO15693_READER_TIMEOUT, &eof_time);

+ start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER;

+ if (answerLen > 0) {

+ Dbprintf("READ SINGLE BLOCK %d returned %d octets:", i, answerLen);

+ DbdecodeIso15693Answer(answerLen, answer);

+ Dbhexdump(answerLen, answer, false);

+ if ( *((uint32_t*) answer) == 0x07160101 ) break; // exit on NoPageErr

}

- i++;

}

- // for the time being, switch field off to protect rdv4.0

+ // for the time being, switch field off to protect RDV4

// note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

LED_D_OFF();

LED_A_OFF();

}

LED_D_OFF();

LED_A_OFF();

}

-// Simulate an ISO15693 TAG.

-// For Inventory command: print command and send Inventory Response with given UID

-// TODO: interpret other reader commands and send appropriate response

-void SimTagIso15693(uint32_t parameter, uint8_t *uid)

-{

- LEDsoff();

- LED_A_ON();

-

+// Initialize the proxmark as iso15k tag

+void Iso15693InitTag(void) {

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

FpgaDownloadAndGo(FPGA_BITSTREAM_HF);

SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);

+ LED_D_OFF();

FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR);

-

StartCountSspClk();

+}

- uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH];

+

+// Simulate an ISO15693 TAG.

+// For Inventory command: print command and send Inventory Response with given UID

+// TODO: interpret other reader commands and send appropriate response

+void SimTagIso15693(uint32_t parameter, uint8_t *uid) {

+

+ LED_A_ON();

+

+ Iso15693InitTag();

// Build a suitable response to the reader INVENTORY command

BuildInventoryResponse(uid);

// Listen to reader

while (!BUTTON_PRESS()) {

// Build a suitable response to the reader INVENTORY command

BuildInventoryResponse(uid);

// Listen to reader

while (!BUTTON_PRESS()) {

+ uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH];

uint32_t eof_time = 0, start_time = 0;

int cmd_len = GetIso15693CommandFromReader(cmd, sizeof(cmd), &eof_time);

if ((cmd_len >= 5) && (cmd[0] & ISO15693_REQ_INVENTORY) && (cmd[1] == ISO15693_INVENTORY)) { // TODO: check more flags

bool slow = !(cmd[0] & ISO15693_REQ_DATARATE_HIGH);

uint32_t eof_time = 0, start_time = 0;

int cmd_len = GetIso15693CommandFromReader(cmd, sizeof(cmd), &eof_time);

if ((cmd_len >= 5) && (cmd[0] & ISO15693_REQ_INVENTORY) && (cmd[1] == ISO15693_INVENTORY)) { // TODO: check more flags

bool slow = !(cmd[0] & ISO15693_REQ_DATARATE_HIGH);

- start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC - DELAY_ARM_TO_READER;

- TransmitTo15693Reader(ToSend, ToSendMax, start_time, slow);

+ start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC_SIM;

+ TransmitTo15693Reader(ToSend, ToSendMax, &start_time, 0, slow);

}

Dbprintf("%d bytes read from reader:", cmd_len);

Dbhexdump(cmd_len, cmd, false);

}

Dbprintf("%d bytes read from reader:", cmd_len);

Dbhexdump(cmd_len, cmd, false);

}

- LEDsoff();

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ LED_D_OFF();

+ LED_A_OFF();

}

// Since there is no standardized way of reading the AFI out of a tag, we will brute force it

// (some manufactures offer a way to read the AFI, though)

}

// Since there is no standardized way of reading the AFI out of a tag, we will brute force it

// (some manufactures offer a way to read the AFI, though)

-void BruteforceIso15693Afi(uint32_t speed)

-{

- LEDsoff();

+void BruteforceIso15693Afi(uint32_t speed) {

LED_A_ON();

- uint8_t data[20];

- uint8_t *recv=data;

- int datalen=0, recvlen=0;

-

- Iso15693InitReader();

+ uint8_t data[6];

+ uint8_t recv[ISO15693_MAX_RESPONSE_LENGTH];

+ int datalen = 0, recvlen = 0;

+ uint32_t eof_time;

// first without AFI

// Tags should respond without AFI and with AFI=0 even when AFI is active

// first without AFI

// Tags should respond without AFI and with AFI=0 even when AFI is active

data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_SLOT1;

data[1] = ISO15693_INVENTORY;

data[2] = 0; // mask length

data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_SLOT1;

data[1] = ISO15693_INVENTORY;

data[2] = 0; // mask length

- datalen = AddCrc(data,3);

- recvlen = SendDataTag(data, datalen, false, speed, &recv);

+ datalen = Iso15693AddCrc(data,3);

+ uint32_t start_time = GetCountSspClk();

+ recvlen = SendDataTag(data, datalen, true, speed, recv, sizeof(recv), 0, ISO15693_READER_TIMEOUT, &eof_time);

+ start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER;

WDT_HIT();

if (recvlen>=12) {

WDT_HIT();

if (recvlen>=12) {

- Dbprintf("NoAFI UID=%s",sprintUID(NULL,&recv[2]));

+ Dbprintf("NoAFI UID=%s", Iso15693sprintUID(NULL, &recv[2]));

}

// now with AFI

}

// now with AFI

data[2] = 0; // AFI

data[3] = 0; // mask length

data[2] = 0; // AFI

data[3] = 0; // mask length

- for (int i=0;i<256;i++) {

- data[2]=i & 0xFF;

- datalen=AddCrc(data,4);

- recvlen=SendDataTag(data, datalen, false, speed, &recv);

+ for (int i = 0; i < 256; i++) {

+ data[2] = i & 0xFF;

+ datalen = Iso15693AddCrc(data,4);

+ recvlen = SendDataTag(data, datalen, false, speed, recv, sizeof(recv), start_time, ISO15693_READER_TIMEOUT, &eof_time);

+ start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER;

WDT_HIT();

- if (recvlen>=12) {

- Dbprintf("AFI=%i UID=%s", i, sprintUID(NULL,&recv[2]));

+ if (recvlen >= 12) {

+ Dbprintf("AFI=%i UID=%s", i, Iso15693sprintUID(NULL, &recv[2]));

}

Dbprintf("AFI Bruteforcing done.");

}

Dbprintf("AFI Bruteforcing done.");

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

- LEDsoff();

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ LED_D_OFF();

+ LED_A_OFF();

+

}

// Allows to directly send commands to the tag via the client

void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t data[]) {

}

// Allows to directly send commands to the tag via the client

void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t data[]) {

- int recvlen=0;

- uint8_t *recvbuf = BigBuf_get_addr();

-

LED_A_ON();

+ int recvlen = 0;

+ uint8_t recvbuf[ISO15693_MAX_RESPONSE_LENGTH];

+ uint32_t eof_time;

+

+ uint16_t timeout;

+ bool request_answer = false;

+

+ switch (data[1]) {

+ case ISO15693_WRITEBLOCK:

+ case ISO15693_LOCKBLOCK:

+ case ISO15693_WRITE_MULTI_BLOCK:

+ case ISO15693_WRITE_AFI:

+ case ISO15693_LOCK_AFI:

+ case ISO15693_WRITE_DSFID:

+ case ISO15693_LOCK_DSFID:

+ timeout = ISO15693_READER_TIMEOUT_WRITE;

+ request_answer = data[0] & ISO15693_REQ_OPTION;

+ break;

+ default:

+ timeout = ISO15693_READER_TIMEOUT;

+ }

+

if (DEBUG) {

- Dbprintf("SEND");

+ Dbprintf("SEND:");

Dbhexdump(datalen, data, false);

}

Dbhexdump(datalen, data, false);

}

- recvlen = SendDataTag(data, datalen, true, speed, (recv?&recvbuf:NULL));

+ recvlen = SendDataTag(data, datalen, true, speed, (recv?recvbuf:NULL), sizeof(recvbuf), 0, timeout, &eof_time);

+

+ if (request_answer) { // send a single EOF to get the tag response

+ recvlen = SendDataTagEOF((recv?recvbuf:NULL), sizeof(recvbuf), 0, ISO15693_READER_TIMEOUT, &eof_time);

+ }

+

+ // for the time being, switch field off to protect rdv4.0

+ // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ LED_D_OFF();

if (recv) {

- cmd_send(CMD_ACK, recvlen>48?48:recvlen, 0, 0, recvbuf, 48);

+ if (DEBUG) {

+ Dbprintf("RECV:");

+ if (recvlen > 0) {

+ Dbhexdump(recvlen, recvbuf, false);

+ DbdecodeIso15693Answer(recvlen, recvbuf);

+ }

+ if (recvlen > ISO15693_MAX_RESPONSE_LENGTH) {

+ recvlen = ISO15693_MAX_RESPONSE_LENGTH;

+ }

+ cmd_send(CMD_ACK, recvlen, 0, 0, recvbuf, ISO15693_MAX_RESPONSE_LENGTH);

+ }

+

+ LED_A_OFF();

+}

+

+//-----------------------------------------------------------------------------

+// Work with "magic Chinese" card.

+//

+//-----------------------------------------------------------------------------

+// Set the UID on Magic ISO15693 tag (based on Iceman's LUA-script).

+void SetTag15693Uid(uint8_t *uid) {

+

+ LED_A_ON();

+

+ uint8_t cmd[4][9] = {

+ {ISO15693_REQ_DATARATE_HIGH, ISO15693_WRITEBLOCK, 0x3e, 0x00, 0x00, 0x00, 0x00},

+ {ISO15693_REQ_DATARATE_HIGH, ISO15693_WRITEBLOCK, 0x3f, 0x69, 0x96, 0x00, 0x00},

+ {ISO15693_REQ_DATARATE_HIGH, ISO15693_WRITEBLOCK, 0x38},

+ {ISO15693_REQ_DATARATE_HIGH, ISO15693_WRITEBLOCK, 0x39}

+ };

+

+ uint16_t crc;

+

+ int recvlen = 0;

+ uint8_t recvbuf[ISO15693_MAX_RESPONSE_LENGTH];

+ uint32_t eof_time;

+

+ // Command 3 : 022138u8u7u6u5 (where uX = uid byte X)

+ cmd[2][3] = uid[7];

+ cmd[2][4] = uid[6];

+ cmd[2][5] = uid[5];

+ cmd[2][6] = uid[4];

+

+ // Command 4 : 022139u4u3u2u1 (where uX = uid byte X)

+ cmd[3][3] = uid[3];

+ cmd[3][4] = uid[2];

+ cmd[3][5] = uid[1];

+ cmd[3][6] = uid[0];

+

+ uint32_t start_time = 0;

+

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

+ // Add the CRC

+ crc = Iso15693Crc(cmd[i], 7);

+ cmd[i][7] = crc & 0xff;

+ cmd[i][8] = crc >> 8;

+

+ recvlen = SendDataTag(cmd[i], sizeof(cmd[i]), i==0?true:false, true, recvbuf, sizeof(recvbuf), start_time, ISO15693_READER_TIMEOUT_WRITE, &eof_time);

+ start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER;

if (DEBUG) {

- Dbprintf("RECV");

- DbdecodeIso15693Answer(recvlen,recvbuf);

- Dbhexdump(recvlen, recvbuf, false);

+ Dbprintf("SEND:");

+ Dbhexdump(sizeof(cmd[i]), cmd[i], false);

+ Dbprintf("RECV:");

+ if (recvlen > 0) {

+ Dbhexdump(recvlen, recvbuf, false);

+ DbdecodeIso15693Answer(recvlen, recvbuf);

+ }

}

+ // Note: need to know if we expect an answer from one of the magic commands

+ // if (recvlen < 0) {

+ // break;

+ // }

}

- // for the time being, switch field off to protect rdv4.0

- // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway

- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

LED_D_OFF();

+ cmd_send(CMD_ACK, recvlen, 0, 0, recvbuf, recvlen);

LED_A_OFF();

}

LED_A_OFF();

}

-

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

// -- Misc & deprecated functions

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

// -- Misc & deprecated functions

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

uint8_t cmd[12];

uint16_t crc;

uint8_t cmd[12];

uint16_t crc;

- // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block

- // followed by teh block data

+ // If we set the Option_Flag in this request, the VICC will respond with the security status of the block

+ // followed by the block data

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// System Information command code

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// System Information command code

cmd[8] = 0x05;

cmd[9]= 0xe0; // always e0 (not exactly unique)

//Now the CRC

cmd[8] = 0x05;

cmd[9]= 0xe0; // always e0 (not exactly unique)

//Now the CRC

- crc = Crc(cmd, 10); // the crc needs to be calculated over 2 bytes

+ crc = Iso15693Crc(cmd, 10); // the crc needs to be calculated over 2 bytes

cmd[10] = crc & 0xff;

cmd[11] = crc >> 8;

cmd[10] = crc & 0xff;

cmd[11] = crc >> 8;

uint8_t cmd[14];

uint16_t crc;

uint8_t cmd[14];

uint16_t crc;

- // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block

- // followed by teh block data

+ // If we set the Option_Flag in this request, the VICC will respond with the security status of the block

+ // followed by the block data

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ Multi BLOCK command code

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ Multi BLOCK command code

// Number of Blocks to read

cmd[11] = 0x2f; // read quite a few

//Now the CRC

// Number of Blocks to read

cmd[11] = 0x2f; // read quite a few

//Now the CRC

- crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

+ crc = Iso15693Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;

uint8_t cmd[14];

uint16_t crc;

uint8_t cmd[14];

uint16_t crc;

- // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block

- // followed by teh block data

+ // If we set the Option_Flag in this request, the VICC will respond with the security status of the block

+ // followed by the block data

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ BLOCK command code

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ BLOCK command code

cmd[10] = 0x00;

cmd[11] = 0x0a;

cmd[10] = 0x00;

cmd[11] = 0x0a;

-// cmd[12] = 0x00;

-// cmd[13] = 0x00; //Now the CRC

- crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

+// cmd[12] = 0x00;

+// cmd[13] = 0x00; //Now the CRC

+ crc = Iso15693Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;

uint8_t cmd[14];

uint16_t crc;

uint8_t cmd[14];

uint16_t crc;

- // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block

- // followed by teh block data

+ // If we set the Option_Flag in this request, the VICC will respond with the security status of the block

+ // followed by the block data

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ BLOCK command code

// one sub-carrier, inventory, 1 slot, fast rate

cmd[0] = (1 << 5) | (1 << 1); // no SELECT bit

// READ BLOCK command code

cmd[8] = 0x05;

cmd[9]= 0xe0; // always e0 (not exactly unique)

// Parameter

cmd[8] = 0x05;

cmd[9]= 0xe0; // always e0 (not exactly unique)

// Parameter

- cmd[10] = 0x05; // for custom codes this must be manufcturer code

+ cmd[10] = 0x05; // for custom codes this must be manufacturer code

cmd[11] = 0x00;

-// cmd[12] = 0x00;

-// cmd[13] = 0x00; //Now the CRC

- crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

+// cmd[12] = 0x00;

+// cmd[13] = 0x00; //Now the CRC

+ crc = Iso15693Crc(cmd, 12); // the crc needs to be calculated over 2 bytes

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;

cmd[12] = crc & 0xff;

cmd[13] = crc >> 8;