X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/65cdf0e3f9598e17c7cd0570ca616f51eec11725..29f8c2cc1501cfcace3f32114f4323ee30bdb487:/armsrc/iso14443b.c diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c index cccf0dd6..355e4a2e 100644 --- a/armsrc/iso14443b.c +++ b/armsrc/iso14443b.c @@ -10,42 +10,47 @@ //----------------------------------------------------------------------------- #include "iso14443b.h" -#define RECEIVE_SAMPLES_TIMEOUT 50000 -#define ISO14443B_DMA_BUFFER_SIZE 256 +#ifndef FWT_TIMEOUT_14B +// defaults to 2000ms +# define FWT_TIMEOUT_14B 35312 +#endif +#ifndef ISO14443B_DMA_BUFFER_SIZE +# define ISO14443B_DMA_BUFFER_SIZE 256 +#endif +#ifndef RECEIVE_MASK +# define RECEIVE_MASK (ISO14443B_DMA_BUFFER_SIZE-1) +#endif // Guard Time (per 14443-2) -#define TR0 0 +#ifndef TR0 +# define TR0 0 +#endif + // Synchronization time (per 14443-2) -#define TR1 0 +#ifndef TR1 +# define TR1 0 +#endif // Frame Delay Time PICC to PCD (per 14443-3 Amendment 1) -#define TR2 0 +#ifndef TR2 +# define TR2 0 +#endif // 4sample #define SEND4STUFFBIT(x) ToSendStuffBit(x);ToSendStuffBit(x);ToSendStuffBit(x);ToSendStuffBit(x); //#define SEND4STUFFBIT(x) ToSendStuffBit(x); + // iceman, this threshold value, what makes 8 a good amplituted for this IQ values? +#ifndef SUBCARRIER_DETECT_THRESHOLD +# define SUBCARRIER_DETECT_THRESHOLD 6 +#endif +static void iso14b_set_timeout(uint32_t timeout); +static void iso14b_set_maxframesize(uint16_t size); static void switch_off(void); // the block number for the ISO14443-4 PCB (used with APDUs) static uint8_t pcb_blocknum = 0; +static uint32_t iso14b_timeout = FWT_TIMEOUT_14B; -static uint32_t iso14b_timeout = RECEIVE_SAMPLES_TIMEOUT; -// param timeout is in ftw_ -void iso14b_set_timeout(uint32_t timeout) { - // 9.4395us = 1etu. - // clock is about 1.5 us - iso14b_timeout = timeout; - if(MF_DBGLEVEL >= 2) Dbprintf("ISO14443B Timeout set to %ld fwt", iso14b_timeout); -} - -static void switch_off(void){ - if (MF_DBGLEVEL > 3) Dbprintf("switch_off"); - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(100); - FpgaDisableSscDma(); - set_tracing(FALSE); - LEDsoff(); -} //============================================================================= // An ISO 14443 Type B tag. We listen for commands from the reader, using @@ -136,6 +141,44 @@ static void DemodInit(uint8_t *data) { // memset(Demod.output, 0x00, MAX_FRAME_SIZE); } + +/* +* 9.4395 us = 1 ETU and clock is about 1.5 us +* 13560000Hz +* 1000ms/s +* timeout in ETUs (time to transfer 1 bit, 9.4395 us) +* +* Formula to calculate FWT (in ETUs) by timeout (in ms): +* fwt = 13560000 * 1000 / (8*16) * timeout; +* Sample: 3sec == 3000ms +* 13560000 * 1000 / (8*16) * 3000 == +* 13560000000 / 384000 = 35312 FWT +* @param timeout is in frame wait time, fwt, measured in ETUs +*/ +static void iso14b_set_timeout(uint32_t timeout) { + #define MAX_TIMEOUT 40542464 // 13560000Hz * 1000ms / (2^32-1) * (8*16) + if(timeout > MAX_TIMEOUT) + timeout = MAX_TIMEOUT; + + iso14b_timeout = timeout; + if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443B Timeout set to %ld fwt", iso14b_timeout); +} +static void iso14b_set_maxframesize(uint16_t size) { + if (size > 256) + size = MAX_FRAME_SIZE; + + Uart.byteCntMax = size; + if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443B Max frame size set to %d bytes", Uart.byteCntMax); +} +static void switch_off(void){ + if (MF_DBGLEVEL > 3) Dbprintf("switch_off"); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(100); + FpgaDisableSscDma(); + set_tracing(FALSE); + LEDsoff(); +} + void AppendCrc14443b(uint8_t* data, int len) { ComputeCrc14443(CRC_14443_B, data, len, data+len, data+len+1); } @@ -284,9 +327,9 @@ static void CodeIso14443bAsTag(const uint8_t *cmd, int len) { * false if we are still waiting for some more */ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { - switch(Uart.state) { + switch (Uart.state) { case STATE_UNSYNCD: - if(!bit) { + if (!bit) { // we went low, so this could be the beginning of an SOF Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF; Uart.posCnt = 0; @@ -296,9 +339,9 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { case STATE_GOT_FALLING_EDGE_OF_SOF: Uart.posCnt++; - if(Uart.posCnt == 2) { // sample every 4 1/fs in the middle of a bit - if(bit) { - if(Uart.bitCnt > 9) { + if (Uart.posCnt == 2) { // sample every 4 1/fs in the middle of a bit + if (bit) { + if (Uart.bitCnt > 9) { // we've seen enough consecutive // zeros that it's a valid SOF Uart.posCnt = 0; @@ -306,8 +349,7 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { Uart.state = STATE_AWAITING_START_BIT; LED_A_ON(); // Indicate we got a valid SOF } else { - // didn't stay down long enough - // before going high, error + // didn't stay down long enough before going high, error Uart.state = STATE_UNSYNCD; } } else { @@ -315,10 +357,9 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { } Uart.bitCnt++; } - if(Uart.posCnt >= 4) Uart.posCnt = 0; - if(Uart.bitCnt > 12) { - // Give up if we see too many zeros without - // a one, too. + if (Uart.posCnt >= 4) Uart.posCnt = 0; + if (Uart.bitCnt > 12) { + // Give up if we see too many zeros without a one, too. LED_A_OFF(); Uart.state = STATE_UNSYNCD; } @@ -326,10 +367,9 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { case STATE_AWAITING_START_BIT: Uart.posCnt++; - if(bit) { - if(Uart.posCnt > 50/2) { // max 57us between characters = 49 1/fs, max 3 etus after low phase of SOF = 24 1/fs - // stayed high for too long between - // characters, error + if (bit) { + if (Uart.posCnt > 50/2) { // max 57us between characters = 49 1/fs, max 3 etus after low phase of SOF = 24 1/fs + // stayed high for too long between characters, error Uart.state = STATE_UNSYNCD; } } else { @@ -343,26 +383,26 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { case STATE_RECEIVING_DATA: Uart.posCnt++; - if(Uart.posCnt == 2) { + if (Uart.posCnt == 2) { // time to sample a bit Uart.shiftReg >>= 1; - if(bit) { + if (bit) { Uart.shiftReg |= 0x200; } Uart.bitCnt++; } - if(Uart.posCnt >= 4) { + if (Uart.posCnt >= 4) { Uart.posCnt = 0; } - if(Uart.bitCnt == 10) { - if((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001)) + if (Uart.bitCnt == 10) { + if ((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001)) { // this is a data byte, with correct // start and stop bits Uart.output[Uart.byteCnt] = (Uart.shiftReg >> 1) & 0xff; Uart.byteCnt++; - if(Uart.byteCnt >= Uart.byteCntMax) { + if (Uart.byteCnt >= Uart.byteCntMax) { // Buffer overflowed, give up LED_A_OFF(); Uart.state = STATE_UNSYNCD; @@ -375,9 +415,9 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { // this is an EOF byte LED_A_OFF(); // Finished receiving Uart.state = STATE_UNSYNCD; - if (Uart.byteCnt != 0) { - return TRUE; - } + if (Uart.byteCnt != 0) + return TRUE; + } else { // this is an error LED_A_OFF(); @@ -391,7 +431,6 @@ static RAMFUNC int Handle14443bReaderUartBit(uint8_t bit) { Uart.state = STATE_UNSYNCD; break; } - return FALSE; } @@ -482,31 +521,33 @@ void WaitForFpgaDelayQueueIsEmpty( uint16_t delay ){ static void TransmitFor14443b_AsTag( uint8_t *response, uint16_t len) { - // Signal field is off with the appropriate LED - LED_D_OFF(); - //uint16_t fpgasendQueueDelay = 0; - - // Modulate BPSK - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK); - - ClearFpgaShiftingRegisters(); - - FpgaSetupSsc(); - volatile uint32_t b; + volatile uint32_t b; + + // Signal field is off with the appropriate LED + LED_D_OFF(); + //uint16_t fpgasendQueueDelay = 0; + + // Modulate BPSK + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK); + SpinDelay(40); + + ClearFpgaShiftingRegisters(); + + 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]; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - b = AT91C_BASE_SSC->SSC_RHR; - (void)b; - } + // 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]; } - - //WaitForFpgaDelayQueueIsEmpty(fpgasendQueueDelay); - AT91C_BASE_SSC->SSC_THR = 0xFF; + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + b = AT91C_BASE_SSC->SSC_RHR; + (void)b; + } + } + + //WaitForFpgaDelayQueueIsEmpty(fpgasendQueueDelay); + AT91C_BASE_SSC->SSC_THR = 0xFF; } //----------------------------------------------------------------------------- // Main loop of simulated tag: receive commands from reader, decide what @@ -556,7 +597,7 @@ void SimulateIso14443bTag(uint32_t pupi) { // ...PUPI/UID supplied from user. Adjust ATQB response accordingly if ( pupi > 0 ) { - uint8_t len = size(respATQB); + uint8_t len = sizeof(respATQB); num_to_bytes(pupi, 4, respATQB+1); ComputeCrc14443(CRC_14443_B, respATQB, 12, &respATQB[len-2], &respATQB[len-1]); } @@ -615,10 +656,10 @@ void SimulateIso14443bTag(uint32_t pupi) { send halt response ( waiting for wupb ) */ - switch(cardSTATE){ + switch (cardSTATE) { case SIM_NOFIELD: case SIM_HALTED: - case SIM_IDLE:{ + case SIM_IDLE: { LogTrace(receivedCmd, len, 0, 0, NULL, TRUE); break; } @@ -634,13 +675,13 @@ void SimulateIso14443bTag(uint32_t pupi) { cardSTATE = SIM_HALTED; break; } - case SIM_ACKNOWLEDGE:{ + case SIM_ACKNOWLEDGE: { TransmitFor14443b_AsTag( encodedOK, encodedOKLen ); LogTrace(respOK, sizeof(respOK), 0, 0, NULL, FALSE); cardSTATE = SIM_IDLE; break; } - case SIM_WORK:{ + case SIM_WORK: { if ( len == 7 && receivedCmd[0] == ISO14443B_HALT ) { cardSTATE = SIM_HALTED; } else if ( len == 11 && receivedCmd[0] == ISO14443B_ATTRIB ) { @@ -669,6 +710,7 @@ void SimulateIso14443bTag(uint32_t pupi) { } ++cmdsReceived; + // iceman, could add a switch to turn this on/off (if off, no logging?) if(cmdsReceived > 1000) { DbpString("14B Simulate, 1000 commands later..."); break; @@ -699,12 +741,9 @@ void SimulateIso14443bTag(uint32_t pupi) { * false if we are still waiting for some more * */ -#ifndef SUBCARRIER_DETECT_THRESHOLD -# define SUBCARRIER_DETECT_THRESHOLD 8 -#endif - static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { - int v=0;// , myI, myQ = 0; + int v = 0, myI = ABS(ci), myQ = ABS(cq); + // The soft decision on the bit uses an estimate of just the // quadrant of the reference angle, not the exact angle. #define MAKE_SOFT_DECISION() { \ @@ -722,7 +761,7 @@ static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by abs(ci) + abs(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() { \ +#define CHECK_FOR_SUBCARRIER_old() { \ if(ci < 0) { \ if(cq < 0) { /* ci < 0, cq < 0 */ \ if (cq < ci) { \ @@ -755,10 +794,8 @@ static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { } //note: couldn't we just use MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2) from common.h - marshmellow -#define CHECK_FOR_SUBCARRIER_un() { \ - myI = ABS(ci); \ - myQ = ABS(cq); \ - v = MAX(myI,myQ) + (MIN(myI,myQ) >> 1); \ +#define CHECK_FOR_SUBCARRIER() { \ + v = MAX(myI, myQ) + (MIN(myI, myQ) >> 1); \ } switch(Demod.state) { @@ -867,27 +904,29 @@ static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { Demod.shiftReg >>= 1; // logic '1' - if(Demod.thisBit > 0) Demod.shiftReg |= 0x200; + if (Demod.thisBit > 0) Demod.shiftReg |= 0x200; ++Demod.bitCount; - if(Demod.bitCount == 10) { + // 1 start 8 data 1 stop = 10 + if (Demod.bitCount == 10) { uint16_t s = Demod.shiftReg; // stop bit == '1', start bit == '0' - if((s & 0x200) && !(s & 0x001)) { - uint8_t b = (s >> 1); - Demod.output[Demod.len] = b; + if ((s & 0x200) && (s & 0x001) == 0 ) { + // left shift to drop the startbit + Demod.output[Demod.len] = (s >> 1) & 0xFF; ++Demod.len; Demod.state = DEMOD_AWAITING_START_BIT; } else { + // this one is a bit hard, either its a correc byte or its unsynced. Demod.state = DEMOD_UNSYNCD; Demod.endTime = GetCountSspClk(); LED_C_OFF(); // This is EOF (start, stop and all data bits == '0' - if(s == 0) return TRUE; + if (s == 0) return TRUE; } } Demod.posCount = 0; @@ -908,9 +947,9 @@ static RAMFUNC int Handle14443bTagSamplesDemod(int ci, int cq) { * quiet: set to 'TRUE' to disable debug output */ static void GetTagSamplesFor14443bDemod() { - bool gotFrame = FALSE; + bool gotFrame = FALSE, finished = FALSE; int lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; - int max = 0, ci = 0, cq = 0, samples = 0; + int ci = 0, cq = 0; uint32_t time_0 = 0, time_stop = 0; BigBuf_free(); @@ -927,60 +966,56 @@ static void GetTagSamplesFor14443bDemod() { if (MF_DBGLEVEL > 1) Dbprintf("FpgaSetupSscDma failed. Exiting"); return; } - - time_0 = GetCountSspClk(); - + // And put the FPGA in the appropriate mode FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ); - - while( !BUTTON_PRESS() ) { - WDT_HIT(); - int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR; - if(behindBy > max) max = behindBy; + // get current clock + time_0 = GetCountSspClk(); + + // rx counter - dma counter? (how much?) & (mod) mask > 2. (since 2bytes at the time is read) + while ( !finished ) { - // rx counter - dma counter? (how much?) & (mod) dma buff / 2. (since 2bytes at the time is read) - while(((lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1)) > 2) { + LED_A_INV(); + WDT_HIT(); - ci = upTo[0]; - cq = upTo[1]; - upTo += 2; - samples += 2; - - // restart DMA buffer to receive again. - if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { - upTo = dmaBuf; - AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo; - AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE; - } - - lastRxCounter -= 2; - if(lastRxCounter <= 0) - lastRxCounter += ISO14443B_DMA_BUFFER_SIZE; + // LSB is a fpga signal bit. + ci = upTo[0] >> 1; + cq = upTo[1] >> 1; + upTo += 2; + lastRxCounter -= 2; - // is this | 0x01 the error? & 0xfe in https://github.com/Proxmark/proxmark3/issues/103 - //gotFrame = Handle14443bTagSamplesDemod(ci & 0xfe, cq & 0xfe); - gotFrame = Handle14443bTagSamplesDemod(ci, cq); - if ( gotFrame ) break; - LED_A_INV(); + // restart DMA buffer to receive again. + if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { + upTo = dmaBuf; + lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; + AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo; + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE; } + // https://github.com/Proxmark/proxmark3/issues/103 + gotFrame = Handle14443bTagSamplesDemod(ci, cq); time_stop = GetCountSspClk() - time_0; - - if(time_stop > iso14b_timeout || gotFrame) break; + + finished = (time_stop > iso14b_timeout || gotFrame); } FpgaDisableSscDma(); - + + if ( upTo ) upTo = NULL; + if (MF_DBGLEVEL >= 3) { - Dbprintf("max behindby = %d, samples = %d, gotFrame = %s, Demod.state = %d, Demod.len = %u", - max, - samples, - (gotFrame) ? "true" : "false", + Dbprintf("Demod.state = %d, Demod.len = %u, PDC_RCR = %u", Demod.state, - Demod.len + Demod.len, + AT91C_BASE_PDC_SSC->PDC_RCR ); } + + // print the last batch of IQ values from FPGA + if (MF_DBGLEVEL == 4) + Dbhexdump(ISO14443B_DMA_BUFFER_SIZE, (uint8_t *)dmaBuf, FALSE); + if ( Demod.len > 0 ) LogTrace(Demod.output, Demod.len, Demod.startTime, Demod.endTime, NULL, FALSE); } @@ -1267,10 +1302,23 @@ uint8_t iso14443b_select_card(iso14b_card_select_t *card ) ComputeCrc14443(CRC_14443_B, Demod.output, Demod.len-2, &crc[0], &crc[1]); if ( crc[0] != Demod.output[1] || crc[1] != Demod.output[2] ) return 3; - - // CID + if (card) { + + // CID card->cid = Demod.output[0]; + + // MAX FRAME + uint16_t maxFrame = card->atqb[5] >> 4; + if (maxFrame < 5) maxFrame = 8 * maxFrame + 16; + else if (maxFrame == 5) maxFrame = 64; + else if (maxFrame == 6) maxFrame = 96; + else if (maxFrame == 7) maxFrame = 128; + else if (maxFrame == 8) maxFrame = 256; + else maxFrame = 257; + iso14b_set_maxframesize(maxFrame); + + // FWT uint8_t fwt = card->atqb[6] >> 4; if ( fwt < 16 ){ uint32_t fwt_time = (302 << fwt); @@ -1501,16 +1549,13 @@ static void iso1444b_setup_snoop(void){ void RAMFUNC SnoopIso14443b(void) { uint32_t time_0 = 0, time_start = 0, time_stop = 0; - + int ci = 0, cq = 0; + int lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; + // We won't start recording the frames that we acquire until we trigger; // a good trigger condition to get started is probably when we see a // response from the tag. - int triggered = TRUE; // TODO: set and evaluate trigger condition - int ci, cq; - int maxBehindBy = 0; - //int behindBy = 0; - int lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; - + bool triggered = TRUE; // TODO: set and evaluate trigger condition bool TagIsActive = FALSE; bool ReaderIsActive = FALSE; @@ -1533,40 +1578,25 @@ void RAMFUNC SnoopIso14443b(void) { for(;;) { WDT_HIT(); - - int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1); - if ( behindBy > maxBehindBy ) - maxBehindBy = behindBy; - - if ( behindBy < 2 ) continue; - ci = upTo[0]; cq = upTo[1]; - upTo += 2; - + upTo += 2; lastRxCounter -= 2; if (upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { upTo = dmaBuf; - lastRxCounter += ISO14443B_DMA_BUFFER_SIZE; + lastRxCounter = ISO14443B_DMA_BUFFER_SIZE; AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE; - WDT_HIT(); - - // TODO: understand whether we can increase/decrease as we want or not? - if ( behindBy > ( 9 * ISO14443B_DMA_BUFFER_SIZE/10) ) { - Dbprintf("blew circular buffer! behindBy=%d", behindBy); - break; - } - - if(!tracing) { - DbpString("Trace full"); + + if (!tracing) { + if (MF_DBGLEVEL >= 2) DbpString("Trace full"); break; } - if(BUTTON_PRESS()) { - DbpString("cancelled"); + if (BUTTON_PRESS()) { + if (MF_DBGLEVEL >= 2) DbpString("cancelled"); break; } } @@ -1578,7 +1608,7 @@ void RAMFUNC SnoopIso14443b(void) { // no need to try decoding reader data if the tag is sending if (Handle14443bReaderUartBit(ci & 0x01)) { - time_stop = (GetCountSspClk()-time_0); + time_stop = GetCountSspClk() - time_0; if (triggered) LogTrace(Uart.output, Uart.byteCnt, time_start, time_stop, NULL, TRUE); @@ -1589,12 +1619,12 @@ void RAMFUNC SnoopIso14443b(void) { /* false-triggered by the commands from the reader. */ DemodReset(); } else { - time_start = (GetCountSspClk()-time_0); + time_start = GetCountSspClk() - time_0; } if (Handle14443bReaderUartBit(cq & 0x01)) { - time_stop = (GetCountSspClk()-time_0); + time_stop = GetCountSspClk() - time_0; if (triggered) LogTrace(Uart.output, Uart.byteCnt, time_start, time_stop, NULL, TRUE); @@ -1605,18 +1635,19 @@ void RAMFUNC SnoopIso14443b(void) { /* false-triggered by the commands from the reader. */ DemodReset(); } else { - time_start = (GetCountSspClk()-time_0); + time_start = GetCountSspClk() - time_0; } ReaderIsActive = (Uart.state > STATE_GOT_FALLING_EDGE_OF_SOF); LED_A_OFF(); } - if(!ReaderIsActive) { + if (!ReaderIsActive) { // no need to try decoding tag data if the reader is sending - and we cannot afford the time // is this | 0x01 the error? & 0xfe in https://github.com/Proxmark/proxmark3/issues/103 - if(Handle14443bTagSamplesDemod(ci & 0xFE, cq & 0xFE)) { + // LSB is a fpga signal bit. + if (Handle14443bTagSamplesDemod(ci >> 1, cq >> 1)) { - time_stop = (GetCountSspClk()-time_0); + time_stop = GetCountSspClk() - time_0; LogTrace(Demod.output, Demod.len, time_start, time_stop, NULL, FALSE); @@ -1625,7 +1656,7 @@ void RAMFUNC SnoopIso14443b(void) { // And ready to receive another response. DemodReset(); } else { - time_start = (GetCountSspClk()-time_0); + time_start = GetCountSspClk() - time_0; } TagIsActive = (Demod.state > DEMOD_GOT_FALLING_EDGE_OF_SOF); } @@ -1634,12 +1665,11 @@ void RAMFUNC SnoopIso14443b(void) { switch_off(); // Snoop DbpString("Snoop statistics:"); - Dbprintf(" Max behind by: %i", maxBehindBy); Dbprintf(" Uart State: %x ByteCount: %i ByteCountMax: %i", Uart.state, Uart.byteCnt, Uart.byteCntMax); Dbprintf(" Trace length: %i", BigBuf_get_traceLen()); // free mem refs. - if ( upTo ) upTo = NULL; + if ( upTo ) upTo = NULL; // Uart.byteCntMax should be set with ATQB value.. }