X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/467340996e7af6563070df2c96c374e6a97b1456..7624e8b21bfb8468ae332a891a20df17f5077e58:/armsrc/iso14443b.c diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c index 1ae1692b..82e5dd6a 100644 --- a/armsrc/iso14443b.c +++ b/armsrc/iso14443b.c @@ -17,6 +17,10 @@ #include "iso14443crc.h" #define RECEIVE_SAMPLES_TIMEOUT 2000 +#define ISO14443B_DMA_BUFFER_SIZE 256 + +// PCB Block number for APDUs +static uint8_t pcb_blocknum = 0; //============================================================================= // An ISO 14443 Type B tag. We listen for commands from the reader, using @@ -310,7 +314,7 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len) } } } - + return FALSE; } @@ -320,10 +324,14 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len) //----------------------------------------------------------------------------- void SimulateIso14443bTag(void) { - // the only commands we understand is REQB, AFI=0, Select All, N=0: - static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 }; - // ... and REQB, AFI=0, Normal Request, N=0: - static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF }; + // the only commands we understand is WUPB, AFI=0, Select All, N=1: + static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 }; // WUPB + // ... and REQB, AFI=0, Normal Request, N=1: + static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF }; // REQB + // ... and HLTB + static const uint8_t cmd3[] = { 0x50, 0xff, 0xff, 0xff, 0xff }; // HLTB + // ... and ATTRIB + static const uint8_t cmd4[] = { 0x1D, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; // ATTRIB // ... and we always respond with ATQB, PUPI = 820de174, Application Data = 0x20381922, // supports only 106kBit/s in both directions, max frame size = 32Bytes, @@ -332,6 +340,11 @@ void SimulateIso14443bTag(void) 0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22, 0x00, 0x21, 0x85, 0x5e, 0xd7 }; + // response to HLTB and ATTRIB + static const uint8_t response2[] = {0x00, 0x78, 0xF0}; + + + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); clear_trace(); set_tracing(TRUE); @@ -347,14 +360,18 @@ void SimulateIso14443bTag(void) uint16_t len; uint16_t cmdsRecvd = 0; - FpgaDownloadAndGo(FPGA_BITSTREAM_HF); - // prepare the (only one) tag answer: CodeIso14443bAsTag(response1, sizeof(response1)); uint8_t *resp1Code = BigBuf_malloc(ToSendMax); - memcpy(resp1Code, ToSend, ToSendMax); + memcpy(resp1Code, ToSend, ToSendMax); uint16_t resp1CodeLen = ToSendMax; + // prepare the (other) tag answer: + CodeIso14443bAsTag(response2, sizeof(response2)); + uint8_t *resp2Code = BigBuf_malloc(ToSendMax); + memcpy(resp2Code, ToSend, ToSendMax); + uint16_t resp2CodeLen = ToSendMax; + // We need to listen to the high-frequency, peak-detected path. SetAdcMuxFor(GPIO_MUXSEL_HIPKD); FpgaSetupSsc(); @@ -376,22 +393,37 @@ void SimulateIso14443bTag(void) // Good, look at the command now. if ( (len == sizeof(cmd1) && memcmp(receivedCmd, cmd1, len) == 0) || (len == sizeof(cmd2) && memcmp(receivedCmd, cmd2, len) == 0) ) { - resp = response1; + resp = response1; respLen = sizeof(response1); - respCode = resp1Code; + respCode = resp1Code; respCodeLen = resp1CodeLen; + } else if ( (len == sizeof(cmd3) && receivedCmd[0] == cmd3[0]) + || (len == sizeof(cmd4) && receivedCmd[0] == cmd4[0]) ) { + resp = response2; + respLen = sizeof(response2); + respCode = resp2Code; + respCodeLen = resp2CodeLen; } else { Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd); // And print whether the CRC fails, just for good measure uint8_t b1, b2; - ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2); - if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) { - // Not so good, try again. - DbpString("+++CRC fail"); - } else { - DbpString("CRC passes"); + if (len >= 3){ // if crc exists + ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2); + if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) { + // Not so good, try again. + DbpString("+++CRC fail"); + + } else { + DbpString("CRC passes"); + } } - break; + //get rid of compiler warning + respCodeLen = 0; + resp = response1; + respLen = 0; + respCode = resp1Code; + //don't crash at new command just wait and see if reader will send other new cmds. + //break; } cmdsRecvd++; @@ -428,13 +460,13 @@ void SimulateIso14443bTag(void) (void)b; } } - + // trace the response: if (tracing) { uint8_t parity[MAX_PARITY_SIZE]; LogTrace(resp, respLen, 0, 0, parity, FALSE); } - + } } @@ -512,7 +544,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) } else { \ v -= cq; \ } \ - } + } */ // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq))) #define CHECK_FOR_SUBCARRIER() { \ @@ -546,7 +578,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) } \ } \ } - + switch(Demod.state) { case DEMOD_UNSYNCD: CHECK_FOR_SUBCARRIER(); @@ -644,7 +676,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) Demod.metric -= Demod.thisBit; } (Demod.metricN)++; -*/ +*/ Demod.shiftReg >>= 1; if(Demod.thisBit > 0) { // logic '1' @@ -712,21 +744,21 @@ static void GetSamplesFor14443bDemod(int n, bool quiet) // Allocate memory from BigBuf for some buffers // free all previous allocations first BigBuf_free(); - + // The response (tag -> reader) that we're receiving. uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE); - + // The DMA buffer, used to stream samples from the FPGA - int8_t *dmaBuf = (int8_t*) BigBuf_malloc(DMA_BUFFER_SIZE); + int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE); // Set up the demodulator for tag -> reader responses. DemodInit(receivedResponse); // Setup and start DMA. - FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE); + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE); int8_t *upTo = dmaBuf; - lastRxCounter = DMA_BUFFER_SIZE; + lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; // Signal field is ON with the appropriate LED: LED_D_ON(); @@ -737,18 +769,18 @@ static void GetSamplesFor14443bDemod(int n, bool quiet) int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR; if(behindBy > max) max = behindBy; - while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (DMA_BUFFER_SIZE-1)) > 2) { + while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1)) > 2) { ci = upTo[0]; cq = upTo[1]; upTo += 2; - if(upTo >= dmaBuf + DMA_BUFFER_SIZE) { + if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { upTo = dmaBuf; AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo; - AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE; + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE; } lastRxCounter -= 2; if(lastRxCounter <= 0) { - lastRxCounter += DMA_BUFFER_SIZE; + lastRxCounter += ISO14443B_DMA_BUFFER_SIZE; } samples += 2; @@ -770,7 +802,6 @@ static void GetSamplesFor14443bDemod(int n, bool quiet) //Tracing if (tracing && Demod.len > 0) { uint8_t parity[MAX_PARITY_SIZE]; - //GetParity(Demod.output, Demod.len, parity); LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE); } } @@ -892,11 +923,102 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len) TransmitFor14443b(); if (tracing) { uint8_t parity[MAX_PARITY_SIZE]; - GetParity(cmd, len, parity); LogTrace(cmd,len, 0, 0, parity, TRUE); } } +/* Sends an APDU to the tag + * TODO: check CRC and preamble + */ +int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *response) +{ + uint8_t message_frame[message_length + 4]; + // PCB + message_frame[0] = 0x0A | pcb_blocknum; + pcb_blocknum ^= 1; + // CID + message_frame[1] = 0; + // INF + memcpy(message_frame + 2, message, message_length); + // EDC (CRC) + ComputeCrc14443(CRC_14443_B, message_frame, message_length + 2, &message_frame[message_length + 2], &message_frame[message_length + 3]); + // send + CodeAndTransmit14443bAsReader(message_frame, message_length + 4); + // get response + GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT*100, TRUE); + if(Demod.len < 3) + { + return 0; + } + // TODO: Check CRC + // copy response contents + if(response != NULL) + { + memcpy(response, Demod.output, Demod.len); + } + return Demod.len; +} + +/* Perform the ISO 14443 B Card Selection procedure + * Currently does NOT do any collision handling. + * It expects 0-1 cards in the device's range. + * TODO: Support multiple cards (perform anticollision) + * TODO: Verify CRC checksums + */ +int iso14443b_select_card() +{ + // WUPB command (including CRC) + // Note: WUPB wakes up all tags, REQB doesn't wake up tags in HALT state + static const uint8_t wupb[] = { 0x05, 0x00, 0x08, 0x39, 0x73 }; + // ATTRIB command (with space for CRC) + uint8_t attrib[] = { 0x1D, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00}; + + // first, wake up the tag + CodeAndTransmit14443bAsReader(wupb, sizeof(wupb)); + GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); + // ATQB too short? + if (Demod.len < 14) + { + return 2; + } + + // select the tag + // copy the PUPI to ATTRIB + memcpy(attrib + 1, Demod.output + 1, 4); + /* copy the protocol info from ATQB (Protocol Info -> Protocol_Type) into + ATTRIB (Param 3) */ + attrib[7] = Demod.output[10] & 0x0F; + ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10); + CodeAndTransmit14443bAsReader(attrib, sizeof(attrib)); + GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); + // Answer to ATTRIB too short? + if(Demod.len < 3) + { + return 2; + } + // reset PCB block number + pcb_blocknum = 0; + return 1; +} + +// Set up ISO 14443 Type B communication (similar to iso14443a_setup) +void iso14443b_setup() { + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + // Set up the synchronous serial port + FpgaSetupSsc(); + // connect Demodulated Signal to ADC: + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + // Signal field is on with the appropriate LED + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD); + + // Start the timer + StartCountSspClk(); + + DemodReset(); + UartReset(); +} //----------------------------------------------------------------------------- // Read a SRI512 ISO 14443B tag. @@ -909,9 +1031,6 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len) //----------------------------------------------------------------------------- void ReadSTMemoryIso14443b(uint32_t dwLast) { - clear_trace(); - set_tracing(TRUE); - uint8_t i = 0x00; FpgaDownloadAndGo(FPGA_BITSTREAM_HF); @@ -927,35 +1046,32 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) // Now give it time to spin up. // Signal field is on with the appropriate LED LED_D_ON(); - FpgaWriteConfWord( - FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ); SpinDelay(200); + clear_trace(); + set_tracing(TRUE); + // First command: wake up the tag using the INITIATE command uint8_t cmd1[] = {0x06, 0x00, 0x97, 0x5b}; - CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); -// LED_A_ON(); GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); -// LED_A_OFF(); if (Demod.len == 0) { - DbpString("No response from tag"); - return; + DbpString("No response from tag"); + return; } else { - Dbprintf("Randomly generated UID from tag (+ 2 byte CRC): %02x %02x %02x", - Demod.output[0], Demod.output[1], Demod.output[2]); + Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x", + Demod.output[0], Demod.output[1], Demod.output[2]); } + // There is a response, SELECT the uid DbpString("Now SELECT tag:"); cmd1[0] = 0x0E; // 0x0E is SELECT cmd1[1] = Demod.output[0]; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); - -// LED_A_ON(); GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); -// LED_A_OFF(); if (Demod.len != 3) { Dbprintf("Expected 3 bytes from tag, got %d", Demod.len); return; @@ -971,15 +1087,13 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]); return; } + // Tag is now selected, // First get the tag's UID: cmd1[0] = 0x0B; ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]); CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one - -// LED_A_ON(); GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); -// LED_A_OFF(); if (Demod.len != 10) { Dbprintf("Expected 10 bytes from tag, got %d", Demod.len); return; @@ -988,12 +1102,12 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]); if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) { Dbprintf("CRC Error reading block! Expected: %04x got: %04x", - (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]); + (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]); // Do not return;, let's go on... (we should retry, maybe ?) } Dbprintf("Tag UID (64 bits): %08x %08x", - (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4], - (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]); + (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4], + (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]); // Now loop to read all 16 blocks, address from 0 to last block Dbprintf("Tag memory dump, block 0 to %d", dwLast); @@ -1008,10 +1122,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) cmd1[1] = i; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); - -// LED_A_ON(); GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); -// LED_A_OFF(); if (Demod.len != 6) { // Check if we got an answer from the tag DbpString("Expected 6 bytes from tag, got less..."); return; @@ -1020,13 +1131,13 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]); if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) { Dbprintf("CRC Error reading block! Expected: %04x got: %04x", - (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]); + (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]); // Do not return;, let's go on... (we should retry, maybe ?) } // Now print out the memory location: Dbprintf("Address=%02x, Contents=%08x, CRC=%04x", i, - (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0], - (Demod.output[4]<<8)+Demod.output[5]); + (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0], + (Demod.output[4]<<8)+Demod.output[5]); if (i == 0xff) { break; } @@ -1049,7 +1160,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) * Memory usage for this function, (within BigBuf) * Last Received command (reader->tag) - MAX_FRAME_SIZE * Last Received command (tag->reader) - MAX_FRAME_SIZE - * DMA Buffer - DMA_BUFFER_SIZE + * DMA Buffer - ISO14443B_DMA_BUFFER_SIZE * Demodulated samples received - all the rest */ void RAMFUNC SnoopIso14443b(void) @@ -1066,7 +1177,7 @@ void RAMFUNC SnoopIso14443b(void) set_tracing(TRUE); // The DMA buffer, used to stream samples from the FPGA - int8_t *dmaBuf = (int8_t*) BigBuf_malloc(DMA_BUFFER_SIZE); + int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE); int lastRxCounter; int8_t *upTo; int ci, cq; @@ -1084,7 +1195,7 @@ void RAMFUNC SnoopIso14443b(void) Dbprintf(" Trace: %i bytes", BigBuf_max_traceLen()); Dbprintf(" Reader -> tag: %i bytes", MAX_FRAME_SIZE); Dbprintf(" tag -> Reader: %i bytes", MAX_FRAME_SIZE); - Dbprintf(" DMA: %i bytes", DMA_BUFFER_SIZE); + Dbprintf(" DMA: %i bytes", ISO14443B_DMA_BUFFER_SIZE); // Signal field is off, no reader signal, no tag signal LEDsoff(); @@ -1096,17 +1207,17 @@ void RAMFUNC SnoopIso14443b(void) // Setup for the DMA. FpgaSetupSsc(); upTo = dmaBuf; - lastRxCounter = DMA_BUFFER_SIZE; - FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE); + lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE); uint8_t parity[MAX_PARITY_SIZE]; bool TagIsActive = FALSE; bool ReaderIsActive = FALSE; - + // And now we loop, receiving samples. for(;;) { int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & - (DMA_BUFFER_SIZE-1); + (ISO14443B_DMA_BUFFER_SIZE-1); if(behindBy > maxBehindBy) { maxBehindBy = behindBy; } @@ -1117,13 +1228,13 @@ void RAMFUNC SnoopIso14443b(void) cq = upTo[1]; upTo += 2; lastRxCounter -= 2; - if(upTo >= dmaBuf + DMA_BUFFER_SIZE) { + if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { upTo = dmaBuf; - lastRxCounter += DMA_BUFFER_SIZE; + lastRxCounter += ISO14443B_DMA_BUFFER_SIZE; AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; - AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE; + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE; WDT_HIT(); - if(behindBy > (9*DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not? + if(behindBy > (9*ISO14443B_DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not? Dbprintf("blew circular buffer! behindBy=%d", behindBy); break; } @@ -1142,7 +1253,6 @@ void RAMFUNC SnoopIso14443b(void) if (!TagIsActive) { // no need to try decoding reader data if the tag is sending if(Handle14443bUartBit(ci & 0x01)) { if(triggered && tracing) { - //GetParity(Uart.output, Uart.byteCnt, parity); LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE); } /* And ready to receive another command. */ @@ -1153,7 +1263,6 @@ void RAMFUNC SnoopIso14443b(void) } if(Handle14443bUartBit(cq & 0x01)) { if(triggered && tracing) { - //GetParity(Uart.output, Uart.byteCnt, parity); LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE); } /* And ready to receive another command. */ @@ -1172,7 +1281,6 @@ void RAMFUNC SnoopIso14443b(void) if(tracing) { uint8_t parity[MAX_PARITY_SIZE]; - //GetParity(Demod.output, Demod.len, parity); LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE); } triggered = TRUE; @@ -1215,32 +1323,18 @@ void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, u SetAdcMuxFor(GPIO_MUXSEL_HIPKD); FpgaSetupSsc(); - set_tracing(TRUE); - -/* if(!powerfield) { - // Make sure that we start from off, since the tags are stateful; - // confusing things will happen if we don't reset them between reads. - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - LED_D_OFF(); - SpinDelay(200); - } - */ - - // if(!GETBIT(GPIO_LED_D)) { // if field is off - // FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ); - // // Signal field is on with the appropriate LED - // LED_D_ON(); - // SpinDelay(200); - // } - - CodeAndTransmit14443bAsReader(data, datalen); + if (datalen){ + set_tracing(TRUE); + + CodeAndTransmit14443bAsReader(data, datalen); - if(recv) { - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); - uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE); - cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen); + if(recv) { + GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE); + uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE); + cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen); + } } - + if(!powerfield) { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LED_D_OFF();