X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/8040711b9026716982b6909cc2c9abdbb930a583..d51717fffdc5859964a3ba878c7c9d92689448de:/armsrc/iso14443b.c diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c index 832d661a..a393ed58 100644 --- a/armsrc/iso14443b.c +++ b/armsrc/iso14443b.c @@ -19,6 +19,10 @@ #define TR1 0 // Frame Delay Time PICC to PCD (per 14443-3 Amendment 1) #define TR2 0 + +// 4sample +#define SEND4STUFFBIT(x) ToSendStuffBit(x);ToSendStuffBit(x);ToSendStuffBit(x);ToSendStuffBit(x); + static void switch_off(void); // the block number for the ISO14443-4 PCB (used with APDUs) @@ -132,7 +136,7 @@ static void DemodInit(uint8_t *data) { } void AppendCrc14443b(uint8_t* data, int len) { - ComputeCrc14443(CRC_14443_B,data,len,data+len,data+len+1); + ComputeCrc14443(CRC_14443_B, data, len, data+len, data+len+1); } //----------------------------------------------------------------------------- @@ -218,80 +222,42 @@ static void CodeIso14443bAsTag(const uint8_t *cmd, int len) { // Send SOF. // 10-11 ETU * 4times samples ZEROS - for(i = 0; i < 10; i++) { - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - } + for(i = 0; i < 10; i++) { SEND4STUFFBIT(0); } // 2-3 ETU * 4times samples ONES - for(i = 0; i < 3; i++) { - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - } + for(i = 0; i < 3; i++) { SEND4STUFFBIT(1); } // data for(i = 0; i < len; ++i) { // Start bit - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); + SEND4STUFFBIT(0); // Data bits b = cmd[i]; for(j = 0; j < 8; ++j) { - if(b & 1) { - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); + if(b & 1) { + SEND4STUFFBIT(1); } else { - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); + SEND4STUFFBIT(0); } b >>= 1; } // Stop bit - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); + SEND4STUFFBIT(1); // Extra Guard bit // For PICC it ranges 0-18us (1etu = 9us) - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - - ToSendStuffBit(1); - ToSendStuffBit(1); + SEND4STUFFBIT(1); } // Send EOF. // 10-11 ETU * 4 sample rate = ZEROS - for(i = 0; i < 10; i++) { - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - ToSendStuffBit(0); - } + for(i = 0; i < 10; i++) { SEND4STUFFBIT(0); } // why this? - for(i = 0; i < 40; i++) { - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - } + for(i = 0; i < 40; i++) { SEND4STUFFBIT(1); } // Convert from last byte pos to length ++ToSendMax; @@ -314,8 +280,7 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { switch(Uart.state) { case STATE_UNSYNCD: if(!bit) { - // we went low, so this could be the beginning - // of an SOF + // we went low, so this could be the beginning of an SOF Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF; Uart.posCnt = 0; Uart.bitCnt = 0; @@ -443,16 +408,15 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len) { // Now run a `software UART' on the stream of incoming samples. UartInit(received); - uint8_t b = 0; - for(;;) { + + uint8_t mask, b = 0; + while( !BUTTON_PRESS() ) { WDT_HIT(); - if(BUTTON_PRESS()) return FALSE; - - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - for(uint8_t mask = 0x80; mask != 0x00; mask >>= 1) { - if(Handle14443bReaderUartBit(b & mask)) { + if ( AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY ) { + b = (uint8_t) AT91C_BASE_SSC->SSC_RHR; + for ( mask = 0x80; mask != 0; mask >>= 1) { + if ( Handle14443bReaderUartBit(b & mask)) { *len = Uart.byteCnt; return TRUE; } @@ -462,30 +426,35 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len) { return FALSE; } + +static void TransmitFor14443b_AsTag( uint8_t *response, uint16_t len) { + + // Signal field is off with the appropriate LED + LED_D_OFF(); + + // Modulate BPSK + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK); + + // 8 ETU / 8bits. 8/4= 2 etus. + AT91C_BASE_SSC->SSC_THR = 0XFF; + + FpgaSetupSsc(); + + // Transmit the response. + for(uint16_t i = 0; i < len;) { + if(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) { + AT91C_BASE_SSC->SSC_THR = response[i]; + ++i; + } + } +} //----------------------------------------------------------------------------- // Main loop of simulated tag: receive commands from reader, decide what // response to send, and send it. //----------------------------------------------------------------------------- -void SimulateIso14443bTag(void) { - // the only commands we understand is WUPB, AFI=0, Select All, N=1: - static const uint8_t cmd1[] = { ISO14443B_REQB, 0x00, 0x08, 0x39, 0x73 }; // WUPB - // ... and REQB, AFI=0, Normal Request, N=1: - static const uint8_t cmd2[] = { ISO14443B_REQB, 0x00, 0x00, 0x71, 0xFF }; // REQB - // ... and HLTB - static const uint8_t cmd3[] = { ISO14443B_HALT, 0xff, 0xff, 0xff, 0xff }; // HLTB - // ... and ATTRIB - static const uint8_t cmd4[] = { ISO14443B_ATTRIB, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; // ATTRIB +void SimulateIso14443bTag(uint32_t pupi) { - // ... and we always respond with ATQB, PUPI = 820de174, Application Data = 0x20381922, - // supports only 106kBit/s in both directions, max frame size = 32Bytes, - // supports ISO14443-4, FWI=8 (77ms), NAD supported, CID not supported: - static const uint8_t response1[] = { - 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}; - + ///////////// setup device. FpgaDownloadAndGo(FPGA_BITSTREAM_HF); // allocate command receive buffer @@ -493,123 +462,161 @@ void SimulateIso14443bTag(void) { BigBuf_Clear_ext(false); clear_trace(); //sim set_tracing(TRUE); - - const uint8_t *resp; - uint8_t *respCode; - uint16_t respLen, respCodeLen, len, cmdsRecvd = 0; - uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE); - - // prepare the (only one) tag answer: - CodeIso14443bAsTag(response1, sizeof(response1)); - uint8_t *resp1Code = BigBuf_malloc(ToSendMax); - memcpy(resp1Code, ToSend, ToSendMax); - uint16_t resp1CodeLen = ToSendMax; - DbpString("Printing Resp1Code:"); - Dbhexdump(resp1CodeLen, resp1Code, 0); - - // 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. + + // connect Demodulated Signal to ADC: SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + // Set up the synchronous serial port FpgaSetupSsc(); + ///////////// - uint32_t time_0 =0; - uint32_t t2r_time =0; - uint32_t r2t_time =0; - cmdsRecvd = 0; + uint16_t len, cmdsReceived = 0; + int cardSTATE = SIM_NOFIELD; + int vHf = 0; // in mV + // uint32_t time_0 = 0; + // uint32_t t2r_time = 0; + // uint32_t r2t_time = 0; + uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE); + + // the only commands we understand is WUPB, AFI=0, Select All, N=1: +// static const uint8_t cmdWUPB[] = { ISO14443B_REQB, 0x00, 0x08, 0x39, 0x73 }; // WUPB + // ... and REQB, AFI=0, Normal Request, N=1: +// static const uint8_t cmdREQB[] = { ISO14443B_REQB, 0x00, 0x00, 0x71, 0xFF }; // REQB + // ... and ATTRIB +// static const uint8_t cmdATTRIB[] = { ISO14443B_ATTRIB, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; // ATTRIB - for(;;) { + // ... if not PUPI/UID is supplied we always respond with ATQB, PUPI = 820de174, Application Data = 0x20381922, + // supports only 106kBit/s in both directions, max frame size = 32Bytes, + // supports ISO14443-4, FWI=8 (77ms), NAD supported, CID not supported: + uint8_t respATQB[] = { 0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, + 0x22, 0x00, 0x21, 0x85, 0x5e, 0xd7 }; + + // response to HLTB and ATTRIB + static const uint8_t respOK[] = {0x00, 0x78, 0xF0}; - if (!GetIso14443bCommandFromReader(receivedCmd, &len)) { - Dbprintf("button pressed, received %d commands", cmdsRecvd); - break; - } - r2t_time = GetCountSspClk(); + // ...PUPI/UID supplied from user. Adjust ATQB response accordingly + if ( pupi > 0 ) { + num_to_bytes(pupi, 4, respATQB+1); + ComputeCrc14443(CRC_14443_B, respATQB, 12, respATQB+13, respATQB+14); + } - if (tracing) - LogTrace(receivedCmd, len, (r2t_time - time_0), (r2t_time - time_0), NULL, TRUE); - + // prepare "ATQB" tag answer (encoded): + CodeIso14443bAsTag(respATQB, sizeof(respATQB)); + uint8_t *encodedATQB = BigBuf_malloc(ToSendMax); + uint16_t encodedATQBLen = ToSendMax; + memcpy(encodedATQB, ToSend, ToSendMax); - // 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; - respLen = sizeof(response1); - 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; - if (len >= 3){ // if crc exists - ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2); - if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) - DbpString("+++CRC fail"); - else - DbpString("CRC passes"); - } - //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; - } + + // prepare "OK" tag answer (encoded): + CodeIso14443bAsTag(respOK, sizeof(respOK)); + uint8_t *encodedOK = BigBuf_malloc(ToSendMax); + uint16_t encodedOKLen = ToSendMax; + memcpy(encodedOK, ToSend, ToSendMax); + + // Simulation loop + while (!BUTTON_PRESS() && !usb_poll_validate_length()) { + WDT_HIT(); - ++cmdsRecvd; + // find reader field + if (cardSTATE == SIM_NOFIELD) { + vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10; + if ( vHf > MF_MINFIELDV ) { + cardSTATE = SIM_IDLE; + LED_A_ON(); + } + } + if (cardSTATE == SIM_NOFIELD) continue; - if(cmdsRecvd > 1000) { - DbpString("1000 commands later..."); + // Get reader command + if (!GetIso14443bCommandFromReader(receivedCmd, &len)) { + Dbprintf("button pressed, received %d commands", cmdsReceived); break; } - if(respCodeLen <= 0) continue; - - // Modulate BPSK - // Signal field is off with the appropriate LED - LED_D_OFF(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK); - - AT91C_BASE_SSC->SSC_THR = 0xff; - - FpgaSetupSsc(); - - // Transmit the response. - uint16_t i = 0; - volatile uint8_t b; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - - AT91C_BASE_SSC->SSC_THR = respCode[i]; - i++; - if(i > respCodeLen) - break; - } - - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - (void)b; + // ISO14443-B protocol states: + // REQ or WUP request in ANY state + // WUP in HALTED state + if (len == 5 ) { + if ( (receivedCmd[0] == ISO14443B_REQB && (receivedCmd[2] & 0x8)== 0x8 && cardSTATE != SIM_HALTED) || + (receivedCmd[0] == ISO14443B_REQB && (receivedCmd[2] & 0x8)== 0) ){ + + TransmitFor14443b_AsTag( encodedATQB, encodedATQBLen ); + LogTrace(respATQB, sizeof(respATQB), 0, 0, NULL, FALSE); + cardSTATE = SIM_SELECTING; + continue; } } - t2r_time = GetCountSspClk(); + /* + * How should this flow go? + * REQB or WUPB + * send response ( waiting for Attrib) + * ATTRIB + * send response ( waiting for commands 7816) + * HALT + send halt response ( waiting for wupb ) + */ - if (tracing) - LogTrace(resp, respLen, (t2r_time-time_0), (t2r_time-time_0), NULL, FALSE); + switch(cardSTATE){ + case SIM_NOFIELD: + case SIM_HALTED: + case SIM_IDLE:{ + LogTrace(receivedCmd, len, 0, 0, NULL, TRUE); + break; + } + case SIM_SELECTING: { + TransmitFor14443b_AsTag( encodedATQB, encodedATQBLen ); + LogTrace(respATQB, sizeof(respATQB), 0, 0, NULL, FALSE); + cardSTATE = SIM_IDLE; + break; + } + case SIM_HALTING: { + TransmitFor14443b_AsTag( encodedOK, encodedOKLen ); + LogTrace(respOK, sizeof(respOK), 0, 0, NULL, FALSE); + cardSTATE = SIM_HALTED; + break; + } + case SIM_ACKNOWLEDGE:{ + TransmitFor14443b_AsTag( encodedOK, encodedOKLen ); + LogTrace(respOK, sizeof(respOK), 0, 0, NULL, FALSE); + cardSTATE = SIM_IDLE; + break; + } + case SIM_WORK:{ + if ( len == 7 && receivedCmd[0] == ISO14443B_HALT ) { + cardSTATE = SIM_HALTED; + } else if ( len == 11 && receivedCmd[0] == ISO14443B_ATTRIB ) { + cardSTATE = SIM_ACKNOWLEDGE; + } else { + // Todo: + // - SLOT MARKER + // - ISO7816 + // - emulate with a memory dump + Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsReceived); + + // CRC Check + uint8_t b1, b2; + if (len >= 3){ // if crc exists + ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2); + if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) + DbpString("+++CRC fail"); + else + DbpString("CRC passes"); + } + cardSTATE = SIM_IDLE; + } + break; + } + default: break; + } + + ++cmdsReceived; + if(cmdsReceived > 1000) { + DbpString("14B Simulate, 1000 commands later..."); + break; + } } - + if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, BigBuf_get_traceLen()); switch_off(); //simulate } @@ -842,7 +849,7 @@ static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { * Demodulate the samples we received from the tag, also log to tracebuffer * quiet: set to 'TRUE' to disable debug output */ -static void GetTagSamplesFor14443bDemod(bool quiet) { +static void GetTagSamplesFor14443bDemod() { bool gotFrame = FALSE; int lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; int max = 0, ci = 0, cq = 0, samples = 0; @@ -907,7 +914,7 @@ static void GetTagSamplesFor14443bDemod(bool quiet) { FpgaDisableSscDma(); - if (!quiet) { + if (MF_DBGLEVEL >= 3) { Dbprintf("max behindby = %d, samples = %d, gotFrame = %s, Demod.state = %d, Demod.len = %u", max, samples, @@ -918,10 +925,6 @@ static void GetTagSamplesFor14443bDemod(bool quiet) { } if ( Demod.len > 0 ) LogTrace(Demod.output, Demod.len, Demod.startTime, Demod.endTime, NULL, FALSE); - - // free mem refs. - // if ( dmaBuf ) dmaBuf = NULL; - // if ( upTo ) upTo = NULL; } @@ -1039,7 +1042,7 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len) { if(trigger) LED_A_ON(); - if (tracing) LogTrace(cmd, len, time_start, GetCountSspClk()-time_start, NULL, TRUE); + LogTrace(cmd, len, time_start, GetCountSspClk()-time_start, NULL, TRUE); } /* Sends an APDU to the tag @@ -1061,7 +1064,7 @@ uint8_t iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *r // send CodeAndTransmit14443bAsReader(message_frame, message_length + 4); //no // get response - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if(Demod.len < 3) return 0; @@ -1090,7 +1093,7 @@ uint8_t iso14443b_select_srx_card(iso14b_card_select_t *card ) uint8_t crc[2] = {0x00, 0x00}; CodeAndTransmit14443bAsReader(init_srx, sizeof(init_srx)); - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len == 0) return 2; @@ -1101,7 +1104,7 @@ uint8_t iso14443b_select_srx_card(iso14b_card_select_t *card ) ComputeCrc14443(CRC_14443_B, select_srx, 2, &select_srx[2], &select_srx[3]); CodeAndTransmit14443bAsReader(select_srx, sizeof(select_srx)); - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len != 3) return 2; @@ -1117,7 +1120,7 @@ uint8_t iso14443b_select_srx_card(iso14b_card_select_t *card ) ComputeCrc14443(CRC_14443_B, select_srx, 1 , &select_srx[1], &select_srx[2]); CodeAndTransmit14443bAsReader(select_srx, 3); // Only first three bytes for this one - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len != 10) return 2; @@ -1151,7 +1154,7 @@ uint8_t iso14443b_select_card(iso14b_card_select_t *card ) // first, wake up the tag CodeAndTransmit14443bAsReader(wupb, sizeof(wupb)); - GetTagSamplesFor14443bDemod(TRUE); //select_card + GetTagSamplesFor14443bDemod(); //select_card // ATQB too short? if (Demod.len < 14) return 2; @@ -1175,7 +1178,7 @@ uint8_t iso14443b_select_card(iso14b_card_select_t *card ) ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10); CodeAndTransmit14443bAsReader(attrib, sizeof(attrib)); - GetTagSamplesFor14443bDemod(TRUE);//select_card + GetTagSamplesFor14443bDemod();//select_card // Answer to ATTRIB too short? if(Demod.len < 3) return 2; @@ -1261,7 +1264,7 @@ void ReadSTMemoryIso14443b(uint8_t numofblocks) // First command: wake up the tag using the INITIATE command uint8_t cmd1[] = {ISO14443B_INITIATE, 0x00, 0x97, 0x5b}; CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); //no - GetTagSamplesFor14443bDemod(TRUE); // no + GetTagSamplesFor14443bDemod(); // no if (Demod.len == 0) { DbpString("No response from tag"); @@ -1278,7 +1281,7 @@ void ReadSTMemoryIso14443b(uint8_t numofblocks) cmd1[1] = Demod.output[0]; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); //no - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len != 3) { Dbprintf("Expected 3 bytes from tag, got %d", Demod.len); set_tracing(FALSE); @@ -1303,7 +1306,7 @@ void ReadSTMemoryIso14443b(uint8_t numofblocks) cmd1[0] = ISO14443B_GET_UID; ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]); CodeAndTransmit14443bAsReader(cmd1, 3); // no -- Only first three bytes for this one - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len != 10) { Dbprintf("Expected 10 bytes from tag, got %d", Demod.len); set_tracing(FALSE); @@ -1334,7 +1337,7 @@ void ReadSTMemoryIso14443b(uint8_t numofblocks) cmd1[1] = i; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); //no - GetTagSamplesFor14443bDemod(TRUE); //no + GetTagSamplesFor14443bDemod(); //no if (Demod.len != 6) { // Check if we got an answer from the tag DbpString("Expected 6 bytes from tag, got less..."); @@ -1627,7 +1630,7 @@ void SendRawCommand14443B_Ex(UsbCommand *c) } CodeAndTransmit14443bAsReader(cmd, len); // raw - GetTagSamplesFor14443bDemod(TRUE); // raw + GetTagSamplesFor14443bDemod(); // raw sendlen = MIN(Demod.len, USB_CMD_DATA_SIZE); status = (Demod.len > 0) ? 0 : 1;