X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/5e174a511b37e17cd3fcaedad608ce605ba34ce9..7361a18f7a24a7b0dd6e76919ef389202543cdc5:/armsrc/iso15693.c diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c index acace295..e3524375 100644 --- a/armsrc/iso15693.c +++ b/armsrc/iso15693.c @@ -1,1111 +1,1743 @@ -//----------------------------------------------------------------------------- -// Routines to support ISO 15693. This includes both the reader software and -// the `fake tag' modes, but at the moment I've implemented only the reader -// stuff, and that barely. -// Jonathan Westhues, split Nov 2006 - -// Modified by Greg Jones, Jan 2009 to perform modulation onboard in arm rather than on PC -// Also added additional reader commands (SELECT, READ etc.) - -//----------------------------------------------------------------------------- -#include -#include "apps.h" - -// FROM winsrc\prox.h ////////////////////////////////// -#define arraylen(x) (sizeof(x)/sizeof((x)[0])) - -//----------------------------------------------------------------------------- -// Map a sequence of octets (~layer 2 command) into the set of bits to feed -// to the FPGA, to transmit that command to the tag. -//----------------------------------------------------------------------------- - - // The sampling rate is 106.353 ksps/s, for T = 18.8 us - - // SOF defined as - // 1) Unmodulated time of 56.64us - // 2) 24 pulses of 423.75khz - // 3) logic '1' (unmodulated for 18.88us followed by 8 pulses of 423.75khz) - - static const int FrameSOF[] = { - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, - -1, -1, -1, -1, - -1, -1, -1, -1, - 1, 1, 1, 1, - 1, 1, 1, 1 - }; - static const int Logic0[] = { - 1, 1, 1, 1, - 1, 1, 1, 1, - -1, -1, -1, -1, - -1, -1, -1, -1 - }; - static const int Logic1[] = { - -1, -1, -1, -1, - -1, -1, -1, -1, - 1, 1, 1, 1, - 1, 1, 1, 1 - }; - - // EOF defined as - // 1) logic '0' (8 pulses of 423.75khz followed by unmodulated for 18.88us) - // 2) 24 pulses of 423.75khz - // 3) Unmodulated time of 56.64us - - static const int FrameEOF[] = { - 1, 1, 1, 1, - 1, 1, 1, 1, - -1, -1, -1, -1, - -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, - 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 - }; - -static void CodeIso15693AsReader(BYTE *cmd, int n) -{ - int i, j; - - ToSendReset(); - - // Give it a bit of slack at the beginning - for(i = 0; i < 24; i++) { - ToSendStuffBit(1); - } - - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - for(i = 0; i < n; i++) { - for(j = 0; j < 8; j += 2) { - int these = (cmd[i] >> j) & 3; - switch(these) { - case 0: - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 1: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 2: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 3: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - break; - } - } - } - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - - // And slack at the end, too. - for(i = 0; i < 24; i++) { - ToSendStuffBit(1); - } -} - -//----------------------------------------------------------------------------- -// The CRC used by ISO 15693. -//----------------------------------------------------------------------------- -static WORD Crc(BYTE *v, int n) -{ - DWORD reg; - int i, j; - - reg = 0xffff; - for(i = 0; i < n; i++) { - reg = reg ^ ((DWORD)v[i]); - for (j = 0; j < 8; j++) { - if (reg & 0x0001) { - reg = (reg >> 1) ^ 0x8408; - } else { - reg = (reg >> 1); - } - } - } - - return ~reg; -} - -char *strcat(char *dest, const char *src) -{ - size_t dest_len = strlen(dest); - size_t i; - - for (i = 0 ; src[i] != '\0' ; i++) - dest[dest_len + i] = src[i]; - dest[dest_len + i] = '\0'; - - return dest; -} - -////////////////////////////////////////// code to do 'itoa' - -/* reverse: reverse string s in place */ -void reverse(char s[]) -{ - int c, i, j; - - for (i = 0, j = strlen(s)-1; i 0); /* delete it */ - if (sign < 0) - s[i++] = '-'; - s[i] = '\0'; - reverse(s); -} - -//////////////////////////////////////// END 'itoa' CODE - -//----------------------------------------------------------------------------- -// 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) -{ - BYTE cmd[5]; - - WORD 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)); -} - -static void __attribute__((unused)) BuildSysInfoRequest(BYTE *uid) -{ - BYTE cmd[12]; - - WORD 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 << 5) | (1 << 1); // no SELECT bit - // System Information command code - cmd[1] = 0x2B; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - 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 - cmd[10] = crc & 0xff; - cmd[11] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -static void BuildSelectRequest( BYTE uid[]) -{ - -// uid[6]=0x31; // this is getting ignored - the uid array is not happening... - BYTE cmd[12]; - - WORD crc; - // one sub-carrier, inventory, 1 slot, fast rate - //cmd[0] = (1 << 2) | (1 << 5) | (1 << 1); // INVENTROY FLAGS - cmd[0] = (1 << 4) | (1 << 5) | (1 << 1); // Select and addressed FLAGS - // SELECT command code - cmd[1] = 0x25; - // 64-bit UID -// cmd[2] = uid[0];//0x32; -// cmd[3]= uid[1];//0x4b; -// cmd[4] = uid[2];//0x03; -// cmd[5] = uid[3];//0x01; -// cmd[6] = uid[4];//0x00; -// cmd[7] = uid[5];//0x10; -// cmd[8] = uid[6];//0x05; - cmd[2] = 0x32;// - cmd[3] = 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; // infineon? - - cmd[9]= 0xe0; // always e0 (not exactly unique) - -// DbpIntegers(cmd[8],cmd[7],cmd[6]); - // Now the CRC - crc = Crc(cmd, 10); // the crc needs to be calculated over 10 bytes - cmd[10] = crc & 0xff; - cmd[11] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -static void __attribute__((unused)) BuildReadBlockRequest(BYTE *uid, BYTE blockNumber ) -{ - BYTE cmd[13]; - - WORD 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 - // READ BLOCK command code - cmd[1] = 0x20; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; - cmd[9]= 0xe0; // always e0 (not exactly unique) - // Block number to read - cmd[10] = blockNumber;//0x00; - //Now the CRC - crc = Crc(cmd, 11); // the crc needs to be calculated over 2 bytes - cmd[11] = crc & 0xff; - cmd[12] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -static void __attribute__((unused)) BuildReadMultiBlockRequest(BYTE *uid) -{ - BYTE cmd[14]; - - WORD 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 << 5) | (1 << 1); // no SELECT bit - // READ Multi BLOCK command code - cmd[1] = 0x23; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; - cmd[9]= 0xe0; // always e0 (not exactly unique) - // First Block number to read - cmd[10] = 0x00; - // 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 - cmd[12] = crc & 0xff; - cmd[13] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -static void __attribute__((unused)) BuildArbitraryRequest(BYTE *uid,BYTE CmdCode) -{ - BYTE cmd[14]; - - WORD 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 << 5) | (1 << 1); // no SELECT bit - // READ BLOCK command code - cmd[1] = CmdCode; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; - cmd[9]= 0xe0; // always e0 (not exactly unique) - // Parameter - 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] = crc & 0xff; - cmd[13] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -static void __attribute__((unused)) BuildArbitraryCustomRequest(BYTE uid[], BYTE CmdCode) -{ - BYTE cmd[14]; - - WORD 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 << 5) | (1 << 1); // no SELECT bit - // READ BLOCK command code - cmd[1] = CmdCode; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; - cmd[9]= 0xe0; // always e0 (not exactly unique) - // Parameter - cmd[10] = 0x05; // for custom codes this must be manufcturer 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] = crc & 0xff; - cmd[13] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -///////////////////////////////////////////////////////////////////////// -// Now the VICC>VCD responses when we are simulating a tag -//////////////////////////////////////////////////////////////////// - - static void BuildInventoryResponse(void) -{ - BYTE cmd[12]; - - WORD crc; - // one sub-carrier, inventory, 1 slot, fast rate - // AFI is at bit 5 (1<<4) when doing an INVENTORY - cmd[0] = 0; //(1 << 2) | (1 << 5) | (1 << 1); - cmd[1] = 0; - // 64-bit UID - cmd[2] = 0x32; - cmd[3]= 0x4b; - cmd[4] = 0x03; - cmd[5] = 0x01; - cmd[6] = 0x00; - cmd[7] = 0x10; - cmd[8] = 0x05; - cmd[9]= 0xe0; - //Now the CRC - crc = Crc(cmd, 10); - cmd[10] = crc & 0xff; - cmd[11] = crc >> 8; - - CodeIso15693AsReader(cmd, sizeof(cmd)); -} - -//----------------------------------------------------------------------------- -// Transmit the command (to the tag) that was placed in ToSend[]. -//----------------------------------------------------------------------------- -static void TransmitTo15693Tag(const BYTE *cmd, int len, int *samples, int *wait) -{ - int c; - -// FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - if(*wait < 10) { *wait = 10; } - -// for(c = 0; c < *wait;) { -// if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { -// AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing! -// c++; -// } -// if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { -// volatile DWORD r = AT91C_BASE_SSC->SSC_RHR; -// (void)r; -// } -// WDT_HIT(); -// } - - c = 0; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - c++; - if(c >= len) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile DWORD r = AT91C_BASE_SSC->SSC_RHR; - (void)r; - } - WDT_HIT(); - } - *samples = (c + *wait) << 3; -} - -//----------------------------------------------------------------------------- -// Transmit the command (to the reader) that was placed in ToSend[]. -//----------------------------------------------------------------------------- -static void TransmitTo15693Reader(const BYTE *cmd, int len, int *samples, int *wait) -{ - int c; - -// FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR); // No requirement to energise my coils - if(*wait < 10) { *wait = 10; } - - c = 0; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - c++; - if(c >= len) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile DWORD r = AT91C_BASE_SSC->SSC_RHR; - (void)r; - } - WDT_HIT(); - } - *samples = (c + *wait) << 3; -} - -static int GetIso15693AnswerFromTag(BYTE *receivedResponse, int maxLen, int *samples, int *elapsed) -{ - int c = 0; - BYTE *dest = (BYTE *)BigBuf; - int getNext = 0; - - SBYTE prev = 0; - -// NOW READ RESPONSE - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - //spindelay(60); // greg - experiment to get rid of some of the 0 byte/failed reads - c = 0; - getNext = FALSE; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x43; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - SBYTE b; - b = (SBYTE)AT91C_BASE_SSC->SSC_RHR; - - // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - SBYTE r; - - if(b < 0) { - r = -b; - } else { - r = b; - } - if(prev < 0) { - r -= prev; - } else { - r += prev; - } - - dest[c++] = (BYTE)r; - - if(c >= 2000) { - break; - } - } else { - prev = b; - } - - getNext = !getNext; - } - } - -////////////////////////////////////////// -/////////// DEMODULATE /////////////////// -////////////////////////////////////////// - - int i, j; - int max = 0, maxPos=0; - - int skip = 4; - -// if(GraphTraceLen < 1000) return; // THIS CHECKS FOR A BUFFER TO SMALL - - // First, correlate for SOF - for(i = 0; i < 100; i++) { - int corr = 0; - for(j = 0; j < arraylen(FrameSOF); j += skip) { - corr += FrameSOF[j]*dest[i+(j/skip)]; - } - if(corr > max) { - max = corr; - maxPos = i; - } - } -// DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip)); - - int k = 0; // this will be our return value - - // greg - If correlation is less than 1 then there's little point in continuing - if ((max/(arraylen(FrameSOF)/skip)) >= 1) - { - - i = maxPos + arraylen(FrameSOF)/skip; - - BYTE outBuf[20]; - memset(outBuf, 0, sizeof(outBuf)); - BYTE mask = 0x01; - for(;;) { - int corr0 = 0, corr1 = 0, corrEOF = 0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr0 += Logic0[j]*dest[i+(j/skip)]; - } - for(j = 0; j < arraylen(Logic1); j += skip) { - corr1 += Logic1[j]*dest[i+(j/skip)]; - } - for(j = 0; j < arraylen(FrameEOF); j += skip) { - corrEOF += FrameEOF[j]*dest[i+(j/skip)]; - } - // Even things out by the length of the target waveform. - corr0 *= 4; - corr1 *= 4; - - if(corrEOF > corr1 && corrEOF > corr0) { -// DbpString("EOF at %d", i); - break; - } else if(corr1 > corr0) { - i += arraylen(Logic1)/skip; - outBuf[k] |= mask; - } else { - i += arraylen(Logic0)/skip; - } - mask <<= 1; - if(mask == 0) { - k++; - mask = 0x01; - } - if((i+(int)arraylen(FrameEOF)) >= 2000) { - DbpString("ran off end!"); - break; - } - } - if(mask != 0x01) { - DbpString("error, uneven octet! (discard extra bits!)"); -/// DbpString(" mask=%02x", mask); - } -// BYTE str1 [8]; -// itoa(k,str1); -// strcat(str1," octets read"); - -// DbpString( str1); // DbpString("%d octets", k); - -// for(i = 0; i < k; i+=3) { -// //DbpString("# %2d: %02x ", i, outBuf[i]); -// DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]); -// } - - for(i = 0; i < k; i++) { - receivedResponse[i] = outBuf[i]; - } - } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip)) - return k; // return the number of bytes demodulated - -/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2)); - -} - -// Now the GetISO15693 message from sniffing command -static int GetIso15693AnswerFromSniff(BYTE *receivedResponse, int maxLen, int *samples, int *elapsed) -{ - int c = 0; - BYTE *dest = (BYTE *)BigBuf; - int getNext = 0; - - SBYTE prev = 0; - -// NOW READ RESPONSE - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - //spindelay(60); // greg - experiment to get rid of some of the 0 byte/failed reads - c = 0; - getNext = FALSE; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x43; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - SBYTE b; - b = (SBYTE)AT91C_BASE_SSC->SSC_RHR; - - // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - SBYTE r; - - if(b < 0) { - r = -b; - } else { - r = b; - } - if(prev < 0) { - r -= prev; - } else { - r += prev; - } - - dest[c++] = (BYTE)r; - - if(c >= 20000) { - break; - } - } else { - prev = b; - } - - getNext = !getNext; - } - } - -////////////////////////////////////////// -/////////// DEMODULATE /////////////////// -////////////////////////////////////////// - - int i, j; - int max = 0, maxPos=0; - - int skip = 4; - -// if(GraphTraceLen < 1000) return; // THIS CHECKS FOR A BUFFER TO SMALL - - // First, correlate for SOF - for(i = 0; i < 19000; i++) { - int corr = 0; - for(j = 0; j < arraylen(FrameSOF); j += skip) { - corr += FrameSOF[j]*dest[i+(j/skip)]; - } - if(corr > max) { - max = corr; - maxPos = i; - } - } -// DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip)); - - int k = 0; // this will be our return value - - // greg - If correlation is less than 1 then there's little point in continuing - if ((max/(arraylen(FrameSOF)/skip)) >= 1) // THIS SHOULD BE 1 - { - - i = maxPos + arraylen(FrameSOF)/skip; - - BYTE outBuf[20]; - memset(outBuf, 0, sizeof(outBuf)); - BYTE mask = 0x01; - for(;;) { - int corr0 = 0, corr1 = 0, corrEOF = 0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr0 += Logic0[j]*dest[i+(j/skip)]; - } - for(j = 0; j < arraylen(Logic1); j += skip) { - corr1 += Logic1[j]*dest[i+(j/skip)]; - } - for(j = 0; j < arraylen(FrameEOF); j += skip) { - corrEOF += FrameEOF[j]*dest[i+(j/skip)]; - } - // Even things out by the length of the target waveform. - corr0 *= 4; - corr1 *= 4; - - if(corrEOF > corr1 && corrEOF > corr0) { -// DbpString("EOF at %d", i); - break; - } else if(corr1 > corr0) { - i += arraylen(Logic1)/skip; - outBuf[k] |= mask; - } else { - i += arraylen(Logic0)/skip; - } - mask <<= 1; - if(mask == 0) { - k++; - mask = 0x01; - } - if((i+(int)arraylen(FrameEOF)) >= 2000) { - DbpString("ran off end!"); - break; - } - } - if(mask != 0x01) { - DbpString("error, uneven octet! (discard extra bits!)"); -/// DbpString(" mask=%02x", mask); - } -// BYTE str1 [8]; -// itoa(k,str1); -// strcat(str1," octets read"); - -// DbpString( str1); // DbpString("%d octets", k); - -// for(i = 0; i < k; i+=3) { -// //DbpString("# %2d: %02x ", i, outBuf[i]); -// DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]); -// } - - for(i = 0; i < k; i++) { - receivedResponse[i] = outBuf[i]; - } - } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip)) - return k; // return the number of bytes demodulated - -/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2)); -} - -//----------------------------------------------------------------------------- -// 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) -{ - int c = 0; - BYTE *dest = (BYTE *)BigBuf; - int getNext = 0; - - SBYTE prev = 0; - - BuildIdentifyRequest(); - - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - - // Give the tags time to energize - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - SpinDelay(100); - - // Now send the command - FpgaSetupSsc(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - - c = 0; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = ToSend[c]; - c++; - if(c == ToSendMax+3) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile DWORD r = AT91C_BASE_SSC->SSC_RHR; - (void)r; - } - WDT_HIT(); - } - - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - - c = 0; - getNext = FALSE; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x43; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - SBYTE b; - b = (SBYTE)AT91C_BASE_SSC->SSC_RHR; - - // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - SBYTE r; - - if(b < 0) { - r = -b; - } else { - r = b; - } - if(prev < 0) { - r -= prev; - } else { - r += prev; - } - - dest[c++] = (BYTE)r; - - if(c >= 2000) { - break; - } - } else { - prev = b; - } - - getNext = !getNext; - } - } -} - -//----------------------------------------------------------------------------- -// 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(DWORD parameter) -{ - LED_A_ON(); - LED_B_ON(); - LED_C_OFF(); - LED_D_OFF(); - -//DbpString(parameter); - - //BYTE *answer0 = (((BYTE *)BigBuf) + 3560); // allow 100 bytes per reponse (way too much) - BYTE *answer1 = (((BYTE *)BigBuf) + 3660); // - BYTE *answer2 = (((BYTE *)BigBuf) + 3760); - BYTE *answer3 = (((BYTE *)BigBuf) + 3860); - //BYTE *TagUID= (((BYTE *)BigBuf) + 3960); // where we hold the uid for hi15reader -// int answerLen0 = 0; - int answerLen1 = 0; - int answerLen2 = 0; - int answerLen3 = 0; - - // Blank arrays - memset(BigBuf + 3660, 0, 300); - - // Setup SSC - FpgaSetupSsc(); - - // Start from off (no field generated) - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); - - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); - - // Give the tags time to energize - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - SpinDelay(200); - - LED_A_ON(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); - - int samples = 0; - int tsamples = 0; - int wait = 0; - int elapsed = 0; - - // FIRST WE RUN AN INVENTORY TO GET THE TAG UID - // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME - BYTE TagUID[7]; // where we hold the uid for hi15reader - -// BuildIdentifyRequest(); -// //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait); -// TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); // No longer ToSendMax+3 -// // Now wait for a response -// responseLen0 = GetIso15693AnswerFromTag(receivedAnswer0, 100, &samples, &elapsed) ; -// if (responseLen0 >=12) // we should do a better check than this -// { -// // really we should check it is a valid mesg -// // but for now just grab what we think is the uid -// TagUID[0] = receivedAnswer0[2]; -// TagUID[1] = receivedAnswer0[3]; -// TagUID[2] = receivedAnswer0[4]; -// TagUID[3] = receivedAnswer0[5]; -// TagUID[4] = receivedAnswer0[6]; -// TagUID[5] = receivedAnswer0[7]; -// TagUID[6] = receivedAnswer0[8]; // IC Manufacturer code -// DbpIntegers(TagUID[6],TagUID[5],TagUID[4]); -//} - - // Now send the IDENTIFY command - BuildIdentifyRequest(); - //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait); - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); // No longer ToSendMax+3 - // Now wait for a response - answerLen1 = GetIso15693AnswerFromTag(answer1, 100, &samples, &elapsed) ; - - 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 - - // Now send the SELECT command - BuildSelectRequest(TagUID); - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); // No longer ToSendMax+3 - // Now wait for a response - answerLen2 = GetIso15693AnswerFromTag(answer2, 100, &samples, &elapsed); - - // Now send the MULTI READ command -// BuildArbitraryRequest(*TagUID,parameter); - BuildArbitraryCustomRequest(TagUID,parameter); -// BuildReadBlockRequest(*TagUID,parameter); -// BuildSysInfoRequest(*TagUID); - //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait); - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); // No longer ToSendMax+3 - // Now wait for a response - answerLen3 = GetIso15693AnswerFromTag(answer3, 100, &samples, &elapsed) ; - - } - - Dbprintf("%d octets read from IDENTIFY request: %x %x %x %x %x %x %x %x %x", answerLen1, - answer1[0], answer1[1], answer1[2], - answer1[3], answer1[4], answer1[5], - answer1[6], answer1[7], answer1[8]); - - Dbprintf("%d octets read from SELECT request: %x %x %x %x %x %x %x %x %x", answerLen2, - answer2[0], answer2[1], answer2[2], - answer2[3], answer2[4], answer2[5], - answer2[6], answer2[7], answer2[8]); - - Dbprintf("%d octets read from XXX request: %x %x %x %x %x %x %x %x %x", answerLen3, - answer3[0], answer3[1], answer3[2], - answer3[3], answer3[4], answer3[5], - answer3[6], answer3[7], answer3[8]); - - -// str2[0]=0; -// for(i = 0; i < responseLen3; i++) { -// itoa(str1,receivedAnswer3[i]); -// strcat(str2,str1); -// } -// DbpString(str2); - - LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); -} - -//----------------------------------------------------------------------------- -// Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands -// all demodulation performed in arm rather than host. - greg -//----------------------------------------------------------------------------- -void SimTagIso15693(DWORD parameter) -{ - LED_A_ON(); - LED_B_ON(); - LED_C_OFF(); - LED_D_OFF(); - - BYTE *answer1 = (((BYTE *)BigBuf) + 3660); // - int answerLen1 = 0; - - // Blank arrays - memset(answer1, 0, 100); - - // Setup SSC - FpgaSetupSsc(); - - // Start from off (no field generated) - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); - - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); - - // Give the tags time to energize -// FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); // NO GOOD FOR SIM TAG!!!! - SpinDelay(200); - - LED_A_OFF(); - LED_B_OFF(); - LED_C_ON(); - LED_D_OFF(); - - int samples = 0; - int tsamples = 0; - int wait = 0; - int elapsed = 0; - - answerLen1 = GetIso15693AnswerFromSniff(answer1, 100, &samples, &elapsed) ; - - if (answerLen1 >=1) // we should do a better check than this - { - // Build a suitable reponse to the reader INVENTORY cocmmand - BuildInventoryResponse(); - TransmitTo15693Reader(ToSend,ToSendMax, &tsamples, &wait); - } - - Dbprintf("%d octets read from reader command: %x %x %x %x %x %x %x %x %x", answerLen1, - answer1[0], answer1[1], answer1[2], - answer1[3], answer1[4], answer1[5], - answer1[6], answer1[7], answer1[8]); - - LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); -} +//----------------------------------------------------------------------------- +// 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 +// +// 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 +// the license. +//----------------------------------------------------------------------------- +// Routines to support ISO 15693. This includes both the reader software and +// the `fake tag' modes. +//----------------------------------------------------------------------------- + +// The ISO 15693 describes two transmission modes from reader to tag, and four +// 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. +// 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 +// 1 out of 4: +// data rate: 26,48 kbit/s (fc/512) +// used for short range, high speed +// +// VICC (tag) -> VCD (reader) +// Modulation: +// 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 +//----------------------------------------------------------------------------- + + +// Random Remarks: +// *) UID is always used "transmission order" (LSB), which is reverse to display order + +// TODO / BUGS / ISSUES: +// *) signal decoding is unable to detect collisions. +// *) 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 "deprecated" +// *) document all the functions + +#include "iso15693.h" + +#include "proxmark3.h" +#include "util.h" +#include "apps.h" +#include "string.h" +#include "iso15693tools.h" +#include "protocols.h" +#include "cmd.h" +#include "BigBuf.h" +#include "fpgaloader.h" + +#define arraylen(x) (sizeof(x)/sizeof((x)[0])) + +static int DEBUG = 0; + +/////////////////////////////////////////////////////////////////////// +// ISO 15693 Part 2 - Air Interface +// This section basicly contains transmission and receiving of bits +/////////////////////////////////////////////////////////////////////// + +#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 2048 // 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 + +// timing. Delays in SSP_CLK ticks. +// SSP_CLK runs at 13,56MHz / 32 = 423.75kHz when simulating a tag +#define DELAY_READER_TO_ARM_SIM 8 +#define DELAY_ARM_TO_READER_SIM 1 +#define DELAY_ISO15693_VCD_TO_VICC_SIM 132 // 132/423.75kHz = 311.5us from end of command EOF to start of tag response +//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when acting as reader +#define DELAY_ISO15693_VCD_TO_VICC_READER 1056 // 1056/3,39MHz = 311.5us from end of command EOF to start of tag response +#define DELAY_ISO15693_VICC_TO_VCD_READER 1017 // 1017/3.39MHz = 300us between end of tag response and next reader command + +// --------------------------- +// Signal Processing +// --------------------------- + +// prepare data using "1 out of 4" code for later transmission +// 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; + + 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(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + for(i = 0; i < n; i++) { + for(j = 0; j < 8; j += 2) { + int these = (cmd[i] >> j) & 3; + switch(these) { + case 0: + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + break; + case 1: + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + break; + case 2: + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + break; + case 3: + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + break; + } + } + } + // EOF + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + + // Fill remainder of last byte with 1 + for(i = 0; i < 4; i++) { + ToSendStuffBit(1); + } + + 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) +{ + 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(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + + for(i = 0; i < n; i++) { + for (j = 0; j<=255; j++) { + if (cmd[i]==j) { + ToSendStuffBit(1); + ToSendStuffBit(0); + } else { + ToSendStuffBit(1); + ToSendStuffBit(1); + } + } + } + // EOF + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + + // Fill remainder of last byte with 1 + for(i = 0; i < 4; i++) { + ToSendStuffBit(1); + } + + ToSendMax++; +} + + +static void CodeIso15693AsTag(uint8_t *cmd, int n) +{ + ToSendReset(); + + // SOF + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + + // 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); + } + } + } + + // EOF + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(0); + + ToSendMax++; +} + + +// Transmit the command (to the tag) that was placed in cmd[]. +static 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); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + + while (GetCountSspClk() < start_time) ; + + LED_B_ON(); + 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) ? 0x0000 : 0xffff; + 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(); +} + + +//----------------------------------------------------------------------------- +// 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) +{ + // 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); + } + + while (GetCountSspClk() < (start_time & 0xfffffff8)) ; + + AT91C_BASE_SSC->SSC_THR = 0x00; // clear TXRDY + + 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--) { + 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; + } + j++; + } + WDT_HIT(); + } + } + } + LED_C_OFF(); +} + + +//============================================================================= +// An ISO 15693 decoder for tag responses (one subcarrier only). +// 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 +// LED handling: +// LED C -> ON once we have received the SOF and are expecting the rest. +// LED C -> OFF once we have received EOF or are unsynced +// +// Returns: true if we received a EOF +// false if we are still waiting for some more +//============================================================================= + +#define NOISE_THRESHOLD 160 // don't try to correlate noise + +typedef struct DecodeTag { + enum { + STATE_TAG_SOF_LOW, + STATE_TAG_SOF_HIGH, + STATE_TAG_SOF_HIGH_END, + STATE_TAG_RECEIVING_DATA, + STATE_TAG_EOF + } state; + int bitCount; + int posCount; + enum { + LOGIC0, + LOGIC1, + SOF_PART1, + SOF_PART2 + } lastBit; + uint16_t shiftReg; + uint16_t max_len; + uint8_t *output; + int len; + int sum1, sum2; +} DecodeTag_t; + + +static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *DecodeTag) +{ + switch(DecodeTag->state) { + case STATE_TAG_SOF_LOW: + // waiting for 12 times low (11 times low is accepted as well) + if (amplitude < NOISE_THRESHOLD) { + DecodeTag->posCount++; + } else { + if (DecodeTag->posCount > 10) { + DecodeTag->posCount = 1; + DecodeTag->sum1 = 0; + DecodeTag->state = STATE_TAG_SOF_HIGH; + } else { + DecodeTag->posCount = 0; + } + } + break; + + case STATE_TAG_SOF_HIGH: + // waiting for 10 times high. Take average over the last 8 + if (amplitude > NOISE_THRESHOLD) { + DecodeTag->posCount++; + if (DecodeTag->posCount > 2) { + DecodeTag->sum1 += amplitude; // keep track of average high value + } + if (DecodeTag->posCount == 10) { + DecodeTag->sum1 >>= 4; // calculate half of average high value (8 samples) + DecodeTag->state = STATE_TAG_SOF_HIGH_END; + } + } else { // high phase was too short + DecodeTag->posCount = 1; + DecodeTag->state = STATE_TAG_SOF_LOW; + } + break; + + case STATE_TAG_SOF_HIGH_END: + // waiting for a falling edge + if (amplitude < DecodeTag->sum1) { // signal drops below 50% average high: a falling edge + 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; + LED_C_ON(); + } else { + DecodeTag->posCount++; + if (DecodeTag->posCount > 13) { // high phase too long + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } + break; + + case STATE_TAG_RECEIVING_DATA: + 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) { + int32_t corr_1 = DecodeTag->sum2 - DecodeTag->sum1; + int32_t corr_0 = -corr_1; + int32_t corr_EOF = (DecodeTag->sum1 + DecodeTag->sum2) / 2; + if (corr_EOF > corr_0 && corr_EOF > corr_1) { + if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF + DecodeTag->state = STATE_TAG_EOF; + } else { + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } else if (corr_1 > corr_0) { + // logic 1 + if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF + DecodeTag->lastBit = SOF_PART2; // SOF completed + } else { + DecodeTag->lastBit = LOGIC1; + DecodeTag->shiftReg >>= 1; + DecodeTag->shiftReg |= 0x80; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + if (DecodeTag->len > DecodeTag->max_len) { + // buffer overflow, give up + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } + } else { + // logic 0 + if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } else { + DecodeTag->lastBit = LOGIC0; + DecodeTag->shiftReg >>= 1; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + if (DecodeTag->len > DecodeTag->max_len) { + // buffer overflow, give up + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } + } + DecodeTag->posCount = 0; + } + DecodeTag->posCount++; + break; + + case STATE_TAG_EOF: + 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) { + int32_t corr_1 = DecodeTag->sum2 - DecodeTag->sum1; + int32_t corr_0 = -corr_1; + int32_t corr_EOF = (DecodeTag->sum1 + DecodeTag->sum2) / 2; + if (corr_EOF > corr_0 || corr_1 > corr_0) { + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } else { + LED_C_OFF(); + return true; + } + } + DecodeTag->posCount++; + break; + + } + + return false; +} + + +static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data, uint16_t max_len) +{ + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + DecodeTag->output = data; + DecodeTag->max_len = max_len; +} + + +static void DecodeTagReset(DecodeTag_t *DecodeTag) +{ + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; +} + + +/* + * Receive and decode the tag response, also log to tracebuffer + */ +static int GetIso15693AnswerFromTag(uint8_t* response, uint16_t max_len, int timeout) +{ + int samples = 0; + bool gotFrame = false; + + uint16_t *dmaBuf = (uint16_t*)BigBuf_malloc(ISO15693_DMA_BUFFER_SIZE*sizeof(uint16_t)); + + // the Decoder data structure + 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 + 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); + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint16_t *upTo = dmaBuf; + + for(;;) { + uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1); + + if (behindBy == 0) continue; + + uint16_t tagdata = *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)) { + 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 + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers + } + + samples++; + + if (Handle15693SamplesFromTag(tagdata, &DecodeTag)) { + gotFrame = true; + break; + } + + if (samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) { + DecodeTag.len = 0; + break; + } + + } + + FpgaDisableSscDma(); + BigBuf_free(); + + if (DEBUG) Dbprintf("samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d", + samples, gotFrame, DecodeTag.state, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount); + + if (DecodeTag.len > 0) { + LogTrace(DecodeTag.output, DecodeTag.len, 0, 0, NULL, false); + } + + return DecodeTag.len; +} + + +//============================================================================= +// An ISO15693 decoder for reader commands. +// +// This function is called 4 times per bit (every 2 subcarrier cycles). +// Subcarrier frequency fs is 848kHz, 1/fs = 1,18us, i.e. function is called every 2,36us +// LED handling: +// LED B -> ON once we have received the SOF and are expecting the rest. +// LED B -> OFF once we have received EOF or are in error state or unsynced +// +// Returns: true if we received a EOF +// false if we are still waiting for some more +//============================================================================= + +typedef struct DecodeReader { + enum { + STATE_READER_UNSYNCD, + 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; + enum { + CODING_1_OUT_OF_4, + CODING_1_OUT_OF_256 + } Coding; + uint8_t shiftReg; + uint8_t bitCount; + int byteCount; + int byteCountMax; + int posCount; + int sum1, sum2; + uint8_t *output; +} DecodeReader_t; + + +static void DecodeReaderInit(DecodeReader_t* DecodeReader, uint8_t *data, uint16_t max_len) +{ + DecodeReader->output = data; + DecodeReader->byteCountMax = max_len; + DecodeReader->state = STATE_READER_UNSYNCD; + DecodeReader->byteCount = 0; + DecodeReader->bitCount = 0; + DecodeReader->posCount = 1; + DecodeReader->shiftReg = 0; +} + + +static void DecodeReaderReset(DecodeReader_t* DecodeReader) +{ + DecodeReader->state = STATE_READER_UNSYNCD; +} + + +static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uint8_t bit, DecodeReader_t *restrict DecodeReader) +{ + switch(DecodeReader->state) { + case STATE_READER_UNSYNCD: + if(!bit) { + // we went low, so this could be the beginning of a 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++; + if(bit) { // detected rising edge + if(DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5) + DecodeReaderReset(DecodeReader); + } else { // SOF + DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF; + } + } else { + if(DecodeReader->posCount > 5) { // stayed low for too long + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } + break; + + case STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF: + DecodeReader->posCount++; + if(!bit) { // detected a falling edge + if (DecodeReader->posCount < 20) { // falling edge too early (nominally expected at 21 earliest) + 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) + DecodeReaderReset(DecodeReader); + } else { // SOF for 1 out of 4 coding + 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 + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } + break; + + case STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF: + DecodeReader->posCount++; + 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) + DecodeReaderReset(DecodeReader); + } else { + DecodeReader->posCount = 1; + DecodeReader->bitCount = 0; + DecodeReader->byteCount = 0; + DecodeReader->sum1 = 1; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256; + LED_B_ON(); + } + } else { // CODING_1_OUT_OF_4 + if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25) + DecodeReaderReset(DecodeReader); + } else { + 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 + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } else { // CODING_1_OUT_OF_4 + if (DecodeReader->posCount > 26) { // signal stayed low for too long + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } + } + break; + + case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4: + DecodeReader->posCount++; + if (bit) { + if (DecodeReader->posCount == 33) { + DecodeReader->posCount = 1; + DecodeReader->bitCount = 0; + DecodeReader->byteCount = 0; + DecodeReader->sum1 = 1; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4; + LED_B_ON(); + } else { + // do nothing, keep waiting + } + } else { // unexpected falling edge + DecodeReaderReset(DecodeReader); + } + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_4: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit; + } else if (DecodeReader->posCount <= 4) { + DecodeReader->sum1 += bit; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit; + } else { + DecodeReader->sum2 += bit; + } + 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 + LED_B_OFF(); // Finished receiving + DecodeReaderReset(DecodeReader); + if (DecodeReader->byteCount != 0) { + return true; + } + } + if (corr10 > corr11) { // detected a 2bit position + DecodeReader->shiftReg >>= 2; + DecodeReader->shiftReg |= (DecodeReader->bitCount << 6); + } + if (DecodeReader->bitCount == 15) { // we have a full byte + DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg; + if (DecodeReader->byteCount > DecodeReader->byteCountMax) { + // buffer overflow, give up + LED_B_OFF(); + DecodeReaderReset(DecodeReader); + } + DecodeReader->bitCount = 0; + DecodeReader->shiftReg = 0; + } else { + DecodeReader->bitCount++; + } + } + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_256: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit; + } else if (DecodeReader->posCount <= 4) { + DecodeReader->sum1 += bit; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit; + } else { + DecodeReader->sum2 += bit; + } + 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 + LED_B_OFF(); // Finished receiving + DecodeReaderReset(DecodeReader); + if (DecodeReader->byteCount != 0) { + return true; + } + } + if (corr10 > corr11) { // detected the bit position + DecodeReader->shiftReg = DecodeReader->bitCount; + } + if (DecodeReader->bitCount == 255) { // we have a full byte + DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg; + if (DecodeReader->byteCount > DecodeReader->byteCountMax) { + // buffer overflow, give up + LED_B_OFF(); + DecodeReaderReset(DecodeReader); + } + } + DecodeReader->bitCount++; + } + break; + + default: + LED_B_OFF(); + DecodeReaderReset(DecodeReader); + break; + } + + return false; +} + + +//----------------------------------------------------------------------------- +// 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). +// +// 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 samples = 0; + bool gotFrame = false; + uint8_t b; + + uint8_t *dmaBuf = BigBuf_malloc(ISO15693_DMA_BUFFER_SIZE); + + // the decoder data structure + DecodeReader_t DecodeReader = {0}; + DecodeReaderInit(&DecodeReader, received, max_len); + + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); + + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); + + // clear receive register and wait for next transfer + uint32_t temp = AT91C_BASE_SSC->SSC_RHR; + (void) temp; + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)) ; + + uint32_t bit_time = GetCountSspClk() & 0xfffffff8; + + // Setup and start DMA. + FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint8_t *upTo = dmaBuf; + + for(;;) { + uint16_t behindBy = ((uint8_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1); + + if (behindBy == 0) continue; + + b = *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)) { + 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 + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers + } + + for (int i = 7; i >= 0; i--) { + if (Handle15693SampleFromReader((b >> i) & 0x01, &DecodeReader)) { + *eof_time = bit_time + samples - DELAY_READER_TO_ARM_SIM; // end of EOF + gotFrame = true; + break; + } + samples++; + } + + if (gotFrame) { + break; + } + + if (BUTTON_PRESS()) { + DecodeReader.byteCount = 0; + break; + } + + WDT_HIT(); + } + + + FpgaDisableSscDma(); + BigBuf_free_keep_EM(); + + 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 (DecodeReader.byteCount > 0) { + LogTrace(DecodeReader.output, DecodeReader.byteCount, 0, *eof_time, NULL, true); + } + + return DecodeReader.byteCount; +} + + +// 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)); +} + + +//----------------------------------------------------------------------------- +// 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(); + LED_A_ON(); + + uint8_t *dest = BigBuf_get_addr(); + + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + BuildIdentifyRequest(); + + // Give the tags time to energize + LED_D_ON(); + SpinDelay(100); + + // Now send the command + TransmitTo15693Tag(ToSend, ToSendMax, 0); + + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)) ; + + 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)) { + uint16_t r = AT91C_BASE_SSC->SSC_RHR; + dest[c++] = r >> 5; + } + } + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); +} + + +void SnoopIso15693(void) +{ + LED_A_ON(); + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + BigBuf_free(); + + clear_trace(); + set_tracing(true); + + // The DMA buffer, used to stream samples from the FPGA + uint16_t* dmaBuf = (uint16_t*)BigBuf_malloc(ISO15693_DMA_BUFFER_SIZE*sizeof(uint16_t)); + uint16_t *upTo; + + // 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)); + + // 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); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + // Setup for the DMA. + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + upTo = dmaBuf; + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + + bool TagIsActive = false; + bool ReaderIsActive = false; + bool ExpectTagAnswer = false; + + // 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 == 0) continue; + + 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)) { + 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; + } + } + } + samples++; + + if (!TagIsActive) { // no need to try decoding reader data if the tag is sending + if (Handle15693SampleFromReader(snoopdata & 0x02, &DecodeReader)) { + FpgaDisableSscDma(); + ExpectTagAnswer = true; + LogTrace(DecodeReader.output, DecodeReader.byteCount, samples, samples, 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); + upTo = dmaBuf; + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + } + if (Handle15693SampleFromReader(snoopdata & 0x01, &DecodeReader)) { + FpgaDisableSscDma(); + ExpectTagAnswer = true; + LogTrace(DecodeReader.output, DecodeReader.byteCount, samples, samples, 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); + upTo = dmaBuf; + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + } + ReaderIsActive = (DecodeReader.state >= STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF); + } + + 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(); + //Use samples as a time measurement + LogTrace(DecodeTag.output, DecodeTag.len, samples, samples, NULL, false); + // And ready to receive another response. + DecodeTagReset(&DecodeTag); + DecodeReaderReset(&DecodeReader); + ExpectTagAnswer = false; + upTo = dmaBuf; + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + } + TagIsActive = (DecodeTag.state >= STATE_TAG_RECEIVING_DATA); + } + + } + + FpgaDisableSscDma(); + BigBuf_free(); + + LEDsoff(); + + DbpString("Snoop statistics:"); + Dbprintf(" ExpectTagAnswer: %d", ExpectTagAnswer); + Dbprintf(" DecodeTag State: %d", DecodeTag.state); + Dbprintf(" DecodeTag byteCnt: %d", DecodeTag.len); + Dbprintf(" DecodeReader State: %d", DecodeReader.state); + Dbprintf(" DecodeReader byteCnt: %d", DecodeReader.byteCount); + Dbprintf(" Trace length: %d", BigBuf_get_traceLen()); +} + + +// Initialize the proxmark as iso15k reader +static void Iso15693InitReader() { + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + // Setup SSC + // FpgaSetupSsc(); + + // Start from off (no field generated) + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(10); + + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + + // Give the tags time to energize + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER); + SpinDelay(250); +} + +/////////////////////////////////////////////////////////////////////// +// ISO 15693 Part 3 - Air Interface +// This section basically contains transmission and receiving of bits +/////////////////////////////////////////////////////////////////////// + + +// uid is in transmission order (which is reverse of display order) +static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber ) +{ + uint8_t cmd[13]; + + uint16_t crc; + // 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] = ISO15693_READBLOCK; + // UID may be optionally specified here + // 64-bit UID + cmd[2] = uid[0]; + cmd[3] = uid[1]; + cmd[4] = uid[2]; + cmd[5] = uid[3]; + cmd[6] = uid[4]; + cmd[7] = uid[5]; + cmd[8] = uid[6]; + cmd[9] = uid[7]; // 0xe0; // always e0 (not exactly unique) + // Block number to read + cmd[10] = blockNumber; + //Now the CRC + crc = Crc(cmd, 11); // the crc needs to be calculated over 11 bytes + cmd[11] = crc & 0xff; + cmd[12] = crc >> 8; + + CodeIso15693AsReader(cmd, sizeof(cmd)); +} + + +// Now the VICC>VCD responses when we are simulating a tag +static void BuildInventoryResponse(uint8_t *uid) +{ + uint8_t cmd[12]; + + uint16_t crc; + + cmd[0] = 0; // No error, no protocol format extension + cmd[1] = 0; // DSFID (data storage format identifier). 0x00 = not supported + // 64-bit UID + cmd[2] = uid[7]; //0x32; + cmd[3] = uid[6]; //0x4b; + cmd[4] = uid[5]; //0x03; + cmd[5] = uid[4]; //0x01; + cmd[6] = uid[3]; //0x00; + cmd[7] = uid[2]; //0x10; + cmd[8] = uid[1]; //0x05; + cmd[9] = uid[0]; //0xe0; + //Now the CRC + crc = Crc(cmd, 10); + cmd[10] = crc & 0xff; + cmd[11] = crc >> 8; + + CodeIso15693AsTag(cmd, sizeof(cmd)); +} + +// 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 contain the tag's answer +// return: lenght of received data +int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t *recv, uint16_t max_recv_len, uint32_t start_time) { + + LED_A_ON(); + LED_B_OFF(); + LED_C_OFF(); + + if (init) Iso15693InitReader(); + + int answerLen=0; + + if (!speed) { + // low speed (1 out of 256) + CodeIso15693AsReader256(send, sendlen); + } else { + // high speed (1 out of 4) + CodeIso15693AsReader(send, sendlen); + } + + TransmitTo15693Tag(ToSend, ToSendMax, start_time); + + // Now wait for a response + if (recv != NULL) { + answerLen = GetIso15693AnswerFromTag(recv, max_recv_len, DELAY_ISO15693_VCD_TO_VICC_READER * 2); + } + + LED_A_OFF(); + + return answerLen; +} + + +// -------------------------------------------------------------------- +// Debug Functions +// -------------------------------------------------------------------- + +// Decodes a message from a tag and displays its metadata and content +#define DBD15STATLEN 48 +void DbdecodeIso15693Answer(int len, uint8_t *d) { + char status[DBD15STATLEN+1]={0}; + uint16_t crc; + + if (len > 3) { + if (d[0] & ISO15693_RES_EXT) + strncat(status,"ProtExt ", DBD15STATLEN); + if (d[0] & ISO15693_RES_ERROR) { + // error + strncat(status,"Error ", DBD15STATLEN); + switch (d[1]) { + case 0x01: + strncat(status,"01:notSupp", DBD15STATLEN); + break; + case 0x02: + strncat(status,"02:notRecog", DBD15STATLEN); + break; + case 0x03: + strncat(status,"03:optNotSupp", DBD15STATLEN); + break; + case 0x0f: + strncat(status,"0f:noInfo", DBD15STATLEN); + break; + case 0x10: + strncat(status,"10:doesn'tExist", DBD15STATLEN); + break; + case 0x11: + strncat(status,"11:lockAgain", DBD15STATLEN); + break; + case 0x12: + strncat(status,"12:locked", DBD15STATLEN); + break; + case 0x13: + strncat(status,"13:progErr", DBD15STATLEN); + break; + case 0x14: + strncat(status,"14:lockErr", DBD15STATLEN); + break; + default: + strncat(status,"unknownErr", DBD15STATLEN); + } + strncat(status," ", DBD15STATLEN); + } else { + strncat(status,"NoErr ", DBD15STATLEN); + } + + crc=Crc(d,len-2); + if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) ) + strncat(status,"CrcOK",DBD15STATLEN); + else + strncat(status,"CrcFail!",DBD15STATLEN); + + Dbprintf("%s",status); + } +} + + + +/////////////////////////////////////////////////////////////////////// +// Functions called via USB/Client +/////////////////////////////////////////////////////////////////////// + +void SetDebugIso15693(uint32_t debug) { + DEBUG=debug; + Dbprintf("Iso15693 Debug is now %s",DEBUG?"on":"off"); + 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(); + + set_tracing(true); + + int answerLen = 0; + uint8_t TagUID[8] = {0x00}; + + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + + uint8_t answer[ISO15693_MAX_RESPONSE_LENGTH]; + + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + // Setup SSC + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + + // Start from off (no field generated) + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(200); + + // Give the tags time to energize + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER); + SpinDelay(200); + StartCountSspClk(); + + + // 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, 0); + + // Now wait for a response + answerLen = GetIso15693AnswerFromTag(answer, sizeof(answer), DELAY_ISO15693_VCD_TO_VICC_READER * 2) ; + uint32_t start_time = GetCountSspClk() + 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:", answerLen); + DbdecodeIso15693Answer(answerLen, answer); + Dbhexdump(answerLen, answer, false); + + // UID is reverse + 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("%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 (answerLen >= 12 && DEBUG) { + for (int i = 0; i < 32; i++) { // sanity check, assume max 32 pages + BuildReadBlockRequest(TagUID, i); + TransmitTo15693Tag(ToSend, ToSendMax, start_time); + int answerLen = GetIso15693AnswerFromTag(answer, sizeof(answer), DELAY_ISO15693_VCD_TO_VICC_READER * 2); + start_time = GetCountSspClk() + 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 + } + } + } + + // 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(); + + 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(); + + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR); + + StartCountSspClk(); + + uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH]; + + // Build a suitable response to the reader INVENTORY command + BuildInventoryResponse(uid); + + // Listen to reader + while (!BUTTON_PRESS()) { + 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_SIM - DELAY_ARM_TO_READER_SIM; + TransmitTo15693Reader(ToSend, ToSendMax, start_time, slow); + } + + Dbprintf("%d bytes read from reader:", cmd_len); + Dbhexdump(cmd_len, cmd, false); + } + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); +} + + +// 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(); + LED_A_ON(); + + uint8_t data[6]; + uint8_t recv[ISO15693_MAX_RESPONSE_LENGTH]; + + int datalen=0, recvlen=0; + + Iso15693InitReader(); + StartCountSspClk(); + + // 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 + datalen = AddCrc(data,3); + recvlen = SendDataTag(data, datalen, false, speed, recv, sizeof(recv), 0); + uint32_t start_time = GetCountSspClk() + DELAY_ISO15693_VICC_TO_VCD_READER; + WDT_HIT(); + if (recvlen>=12) { + Dbprintf("NoAFI UID=%s", sprintUID(NULL, &recv[2])); + } + + // now with AFI + + data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_AFI | ISO15693_REQINV_SLOT1; + data[1] = ISO15693_INVENTORY; + 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, sizeof(recv), start_time); + start_time = GetCountSspClk() + DELAY_ISO15693_VICC_TO_VCD_READER; + WDT_HIT(); + if (recvlen >= 12) { + Dbprintf("AFI=%i UID=%s", i, sprintUID(NULL, &recv[2])); + } + } + Dbprintf("AFI Bruteforcing done."); + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); +} + +// 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[ISO15693_MAX_RESPONSE_LENGTH]; + + LED_A_ON(); + + if (DEBUG) { + Dbprintf("SEND:"); + Dbhexdump(datalen, data, false); + } + + recvlen = SendDataTag(data, datalen, true, speed, (recv?recvbuf:NULL), sizeof(recvbuf), 0); + + if (recv) { + if (DEBUG) { + Dbprintf("RECV:"); + Dbhexdump(recvlen, recvbuf, false); + DbdecodeIso15693Answer(recvlen, recvbuf); + } + + cmd_send(CMD_ACK, recvlen>ISO15693_MAX_RESPONSE_LENGTH?ISO15693_MAX_RESPONSE_LENGTH:recvlen, 0, 0, recvbuf, ISO15693_MAX_RESPONSE_LENGTH); + + } + + // 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(); + + LED_A_OFF(); +} + + + + +// -------------------------------------------------------------------- +// -- Misc & deprecated functions +// -------------------------------------------------------------------- + +/* + +// do not use; has a fix UID +static void __attribute__((unused)) BuildSysInfoRequest(uint8_t *uid) +{ + uint8_t cmd[12]; + + uint16_t crc; + // 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 + cmd[1] = 0x2B; + // UID may be optionally specified here + // 64-bit UID + cmd[2] = 0x32; + cmd[3]= 0x4b; + cmd[4] = 0x03; + cmd[5] = 0x01; + cmd[6] = 0x00; + cmd[7] = 0x10; + 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 + cmd[10] = crc & 0xff; + cmd[11] = crc >> 8; + + CodeIso15693AsReader(cmd, sizeof(cmd)); +} + + +// do not use; has a fix UID +static void __attribute__((unused)) BuildReadMultiBlockRequest(uint8_t *uid) +{ + uint8_t cmd[14]; + + uint16_t crc; + // 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 + cmd[1] = 0x23; + // UID may be optionally specified here + // 64-bit UID + cmd[2] = 0x32; + cmd[3]= 0x4b; + cmd[4] = 0x03; + cmd[5] = 0x01; + cmd[6] = 0x00; + cmd[7] = 0x10; + cmd[8] = 0x05; + cmd[9]= 0xe0; // always e0 (not exactly unique) + // First Block number to read + cmd[10] = 0x00; + // 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 + cmd[12] = crc & 0xff; + cmd[13] = crc >> 8; + + CodeIso15693AsReader(cmd, sizeof(cmd)); +} + +// do not use; has a fix UID +static void __attribute__((unused)) BuildArbitraryRequest(uint8_t *uid,uint8_t CmdCode) +{ + uint8_t cmd[14]; + + uint16_t crc; + // 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 + cmd[1] = CmdCode; + // UID may be optionally specified here + // 64-bit UID + cmd[2] = 0x32; + cmd[3]= 0x4b; + cmd[4] = 0x03; + cmd[5] = 0x01; + cmd[6] = 0x00; + cmd[7] = 0x10; + cmd[8] = 0x05; + cmd[9]= 0xe0; // always e0 (not exactly unique) + // Parameter + 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] = crc & 0xff; + cmd[13] = crc >> 8; + + CodeIso15693AsReader(cmd, sizeof(cmd)); +} + +// do not use; has a fix UID +static void __attribute__((unused)) BuildArbitraryCustomRequest(uint8_t uid[], uint8_t CmdCode) +{ + uint8_t cmd[14]; + + uint16_t crc; + // 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 + cmd[1] = CmdCode; + // UID may be optionally specified here + // 64-bit UID + cmd[2] = 0x32; + cmd[3]= 0x4b; + cmd[4] = 0x03; + cmd[5] = 0x01; + cmd[6] = 0x00; + cmd[7] = 0x10; + cmd[8] = 0x05; + cmd[9]= 0xe0; // always e0 (not exactly unique) + // Parameter + 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] = crc & 0xff; + cmd[13] = crc >> 8; + + CodeIso15693AsReader(cmd, sizeof(cmd)); +} + + + + +*/ + +