]> cvs.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/iso14443a.c
setting svn:eol-style=native on files, part 3
[proxmark3-svn] / armsrc / iso14443a.c
index a02d7d42d4f7cfeb5264789205607303f00cbef1..2e91d2638eafee4df5e08f2defe7b0e7ab799ec9 100644 (file)
-//-----------------------------------------------------------------------------\r
-// Routines to support ISO 14443 type A.\r
-//\r
-// Gerhard de Koning Gans - May 2008\r
-//-----------------------------------------------------------------------------\r
-#include <proxmark3.h>\r
-#include "apps.h"\r
-#include "../common/iso14443_crc.c"\r
-\r
-static BYTE *trace = (BYTE *) BigBuf;\r
-static int traceLen = 0;\r
-static int rsamples = 0;\r
-\r
-typedef enum {\r
-       SEC_D = 1,\r
-       SEC_E = 2,\r
-       SEC_F = 3,\r
-       SEC_X = 4,\r
-       SEC_Y = 5,\r
-       SEC_Z = 6\r
-} SecType;\r
-\r
-static const BYTE OddByteParity[256] = {\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,\r
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1\r
-};\r
-\r
-//-----------------------------------------------------------------------------\r
-// Generate the parity value for a byte sequence\r
-// \r
-//-----------------------------------------------------------------------------\r
-DWORD GetParity(const BYTE * pbtCmd, int iLen)\r
-{\r
-  int i;\r
-  DWORD dwPar = 0;\r
-  \r
-  // Generate the encrypted data\r
-  for (i = 0; i < iLen; i++) {\r
-    // Save the encrypted parity bit\r
-    dwPar |= ((OddByteParity[pbtCmd[i]]) << i);\r
-  }\r
-  return dwPar;\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// The software UART that receives commands from the reader, and its state\r
-// variables.\r
-//-----------------------------------------------------------------------------\r
-static struct {\r
-    enum {\r
-        STATE_UNSYNCD,\r
-        STATE_START_OF_COMMUNICATION,\r
-               STATE_MILLER_X,\r
-               STATE_MILLER_Y,\r
-               STATE_MILLER_Z,\r
-        STATE_ERROR_WAIT\r
-    }       state;\r
-    WORD    shiftReg;\r
-    int     bitCnt;\r
-    int     byteCnt;\r
-    int     byteCntMax;\r
-    int     posCnt;\r
-    int     syncBit;\r
-       int     parityBits;\r
-       int     samples;\r
-    int     highCnt;\r
-    int     bitBuffer;\r
-       enum {\r
-               DROP_NONE,\r
-               DROP_FIRST_HALF,\r
-               DROP_SECOND_HALF\r
-       }               drop;\r
-    BYTE   *output;\r
-} Uart;\r
-\r
-static BOOL MillerDecoding(int bit)\r
-{\r
-       int error = 0;\r
-       int bitright;\r
-\r
-       if(!Uart.bitBuffer) {\r
-               Uart.bitBuffer = bit ^ 0xFF0;\r
-               return FALSE;\r
-       }\r
-       else {\r
-               Uart.bitBuffer <<= 4;\r
-               Uart.bitBuffer ^= bit;\r
-       }\r
-\r
-       BOOL EOC = FALSE;\r
-\r
-       if(Uart.state != STATE_UNSYNCD) {\r
-               Uart.posCnt++;\r
-\r
-               if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {\r
-                       bit = 0x00;\r
-               }\r
-               else {\r
-                       bit = 0x01;\r
-               }\r
-               if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {\r
-                       bitright = 0x00;\r
-               }\r
-               else {\r
-                       bitright = 0x01;\r
-               }\r
-               if(bit != bitright) { bit = bitright; }\r
-\r
-               if(Uart.posCnt == 1) {\r
-                       // measurement first half bitperiod\r
-                       if(!bit) {\r
-                               Uart.drop = DROP_FIRST_HALF;\r
-                       }\r
-               }\r
-               else {\r
-                       // measurement second half bitperiod\r
-                       if(!bit & (Uart.drop == DROP_NONE)) {\r
-                               Uart.drop = DROP_SECOND_HALF;\r
-                       }\r
-                       else if(!bit) {\r
-                               // measured a drop in first and second half\r
-                               // which should not be possible\r
-                               Uart.state = STATE_ERROR_WAIT;\r
-                               error = 0x01;\r
-                       }\r
-\r
-                       Uart.posCnt = 0;\r
-\r
-                       switch(Uart.state) {\r
-                               case STATE_START_OF_COMMUNICATION:\r
-                                       Uart.shiftReg = 0;\r
-                                       if(Uart.drop == DROP_SECOND_HALF) {\r
-                                               // error, should not happen in SOC\r
-                                               Uart.state = STATE_ERROR_WAIT;\r
-                                               error = 0x02;\r
-                                       }\r
-                                       else {\r
-                                               // correct SOC\r
-                                               Uart.state = STATE_MILLER_Z;\r
-                                       }\r
-                                       break;\r
-\r
-                               case STATE_MILLER_Z:\r
-                                       Uart.bitCnt++;\r
-                                       Uart.shiftReg >>= 1;\r
-                                       if(Uart.drop == DROP_NONE) {\r
-                                               // logic '0' followed by sequence Y\r
-                                               // end of communication\r
-                                               Uart.state = STATE_UNSYNCD;\r
-                                               EOC = TRUE;\r
-                                       }\r
-                                       // if(Uart.drop == DROP_FIRST_HALF) {\r
-                                       //      Uart.state = STATE_MILLER_Z; stay the same\r
-                                       //      we see a logic '0' }\r
-                                       if(Uart.drop == DROP_SECOND_HALF) {\r
-                                               // we see a logic '1'\r
-                                               Uart.shiftReg |= 0x100;\r
-                                               Uart.state = STATE_MILLER_X;\r
-                                       }\r
-                                       break;\r
-\r
-                               case STATE_MILLER_X:\r
-                                       Uart.shiftReg >>= 1;\r
-                                       if(Uart.drop == DROP_NONE) {\r
-                                               // sequence Y, we see a '0'\r
-                                               Uart.state = STATE_MILLER_Y;\r
-                                               Uart.bitCnt++;\r
-                                       }\r
-                                       if(Uart.drop == DROP_FIRST_HALF) {\r
-                                               // Would be STATE_MILLER_Z\r
-                                               // but Z does not follow X, so error\r
-                                               Uart.state = STATE_ERROR_WAIT;\r
-                                               error = 0x03;\r
-                                       }\r
-                                       if(Uart.drop == DROP_SECOND_HALF) {\r
-                                               // We see a '1' and stay in state X\r
-                                               Uart.shiftReg |= 0x100;\r
-                                               Uart.bitCnt++;\r
-                                       }\r
-                                       break;\r
-\r
-                               case STATE_MILLER_Y:\r
-                                       Uart.bitCnt++;\r
-                                       Uart.shiftReg >>= 1;\r
-                                       if(Uart.drop == DROP_NONE) {\r
-                                               // logic '0' followed by sequence Y\r
-                                               // end of communication\r
-                                               Uart.state = STATE_UNSYNCD;\r
-                                               EOC = TRUE;\r
-                                       }\r
-                                       if(Uart.drop == DROP_FIRST_HALF) {\r
-                                               // we see a '0'\r
-                                               Uart.state = STATE_MILLER_Z;\r
-                                       }\r
-                                       if(Uart.drop == DROP_SECOND_HALF) {\r
-                                               // We see a '1' and go to state X\r
-                                               Uart.shiftReg |= 0x100;\r
-                                               Uart.state = STATE_MILLER_X;\r
-                                       }\r
-                                       break;\r
-\r
-                               case STATE_ERROR_WAIT:\r
-                                       // That went wrong. Now wait for at least two bit periods\r
-                                       // and try to sync again\r
-                                       if(Uart.drop == DROP_NONE) {\r
-                                               Uart.highCnt = 6;\r
-                                               Uart.state = STATE_UNSYNCD;\r
-                                       }\r
-                                       break;\r
-\r
-                               default:\r
-                                       Uart.state = STATE_UNSYNCD;\r
-                                       Uart.highCnt = 0;\r
-                                       break;\r
-                       }\r
-\r
-                       Uart.drop = DROP_NONE;\r
-\r
-                       // should have received at least one whole byte...\r
-                       if((Uart.bitCnt == 2) && EOC && (Uart.byteCnt > 0)) {\r
-                               return TRUE;\r
-                       }\r
-\r
-                       if(Uart.bitCnt == 9) {\r
-                               Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);\r
-                               Uart.byteCnt++;\r
-\r
-                               Uart.parityBits <<= 1;\r
-                               Uart.parityBits ^= ((Uart.shiftReg >> 8) & 0x01);\r
-\r
-                               if(EOC) {\r
-                                       // when End of Communication received and\r
-                                       // all data bits processed..\r
-                                       return TRUE;\r
-                               }\r
-                               Uart.bitCnt = 0;\r
-                       }\r
-\r
-                       /*if(error) {\r
-                               Uart.output[Uart.byteCnt] = 0xAA;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = error & 0xFF;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = 0xAA;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;\r
-                               Uart.byteCnt++;\r
-                               Uart.output[Uart.byteCnt] = 0xAA;\r
-                               Uart.byteCnt++;\r
-                               return TRUE;\r
-                       }*/\r
-               }\r
-\r
-       }\r
-       else {\r
-               bit = Uart.bitBuffer & 0xf0;\r
-               bit >>= 4;\r
-               bit ^= 0x0F;\r
-               if(bit) {\r
-                       // should have been high or at least (4 * 128) / fc\r
-                       // according to ISO this should be at least (9 * 128 + 20) / fc\r
-                       if(Uart.highCnt == 8) {\r
-                               // we went low, so this could be start of communication\r
-                               // it turns out to be safer to choose a less significant\r
-                               // syncbit... so we check whether the neighbour also represents the drop\r
-                               Uart.posCnt = 1;   // apparently we are busy with our first half bit period\r
-                               Uart.syncBit = bit & 8;\r
-                               Uart.samples = 3;\r
-                               if(!Uart.syncBit)       { Uart.syncBit = bit & 4; Uart.samples = 2; }\r
-                               else if(bit & 4)        { Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }\r
-                               if(!Uart.syncBit)       { Uart.syncBit = bit & 2; Uart.samples = 1; }\r
-                               else if(bit & 2)        { Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }\r
-                               if(!Uart.syncBit)       { Uart.syncBit = bit & 1; Uart.samples = 0;\r
-                                       if(Uart.syncBit & (Uart.bitBuffer & 8)) {\r
-                                               Uart.syncBit = 8;\r
-\r
-                                               // the first half bit period is expected in next sample\r
-                                               Uart.posCnt = 0;\r
-                                               Uart.samples = 3;\r
-                                       }\r
-                               }\r
-                               else if(bit & 1)        { Uart.syncBit = bit & 1; Uart.samples = 0; }\r
-\r
-                               Uart.syncBit <<= 4;\r
-                               Uart.state = STATE_START_OF_COMMUNICATION;\r
-                               Uart.drop = DROP_FIRST_HALF;\r
-                               Uart.bitCnt = 0;\r
-                               Uart.byteCnt = 0;\r
-                               Uart.parityBits = 0;\r
-                               error = 0;\r
-                       }\r
-                       else {\r
-                               Uart.highCnt = 0;\r
-                       }\r
-               }\r
-               else {\r
-                       if(Uart.highCnt < 8) {\r
-                               Uart.highCnt++;\r
-                       }\r
-               }\r
-       }\r
-\r
-    return FALSE;\r
-}\r
-\r
-//=============================================================================\r
-// ISO 14443 Type A - Manchester\r
-//=============================================================================\r
-\r
-static struct {\r
-    enum {\r
-        DEMOD_UNSYNCD,\r
-               DEMOD_START_OF_COMMUNICATION,\r
-               DEMOD_MANCHESTER_D,\r
-               DEMOD_MANCHESTER_E,\r
-               DEMOD_MANCHESTER_F,\r
-        DEMOD_ERROR_WAIT\r
-    }       state;\r
-    int     bitCount;\r
-    int     posCount;\r
-       int     syncBit;\r
-       int     parityBits;\r
-    WORD    shiftReg;\r
-       int     buffer;\r
-       int     buff;\r
-       int     samples;\r
-    int     len;\r
-       enum {\r
-               SUB_NONE,\r
-               SUB_FIRST_HALF,\r
-               SUB_SECOND_HALF\r
-       }               sub;\r
-    BYTE   *output;\r
-} Demod;\r
-\r
-static BOOL ManchesterDecoding(int v)\r
-{\r
-       int bit;\r
-       int modulation;\r
-       int error = 0;\r
-\r
-       if(!Demod.buff) {\r
-               Demod.buff = 1;\r
-               Demod.buffer = v;\r
-               return FALSE;\r
-       }\r
-       else {\r
-               bit = Demod.buffer;\r
-               Demod.buffer = v;\r
-       }\r
-\r
-       if(Demod.state==DEMOD_UNSYNCD) {\r
-               Demod.output[Demod.len] = 0xfa;\r
-               Demod.syncBit = 0;\r
-               //Demod.samples = 0;\r
-               Demod.posCount = 1;             // This is the first half bit period, so after syncing handle the second part\r
-               if(bit & 0x08) { Demod.syncBit = 0x08; }\r
-               if(!Demod.syncBit)      {\r
-                       if(bit & 0x04) { Demod.syncBit = 0x04; }\r
-               }\r
-               else if(bit & 0x04) { Demod.syncBit = 0x04; bit <<= 4; }\r
-               if(!Demod.syncBit)      {\r
-                       if(bit & 0x02) { Demod.syncBit = 0x02; }\r
-               }\r
-               else if(bit & 0x02) { Demod.syncBit = 0x02; bit <<= 4; }\r
-               if(!Demod.syncBit)      {\r
-                       if(bit & 0x01) { Demod.syncBit = 0x01; }\r
-\r
-                       if(Demod.syncBit & (Demod.buffer & 0x08)) {\r
-                               Demod.syncBit = 0x08;\r
-\r
-                               // The first half bitperiod is expected in next sample\r
-                               Demod.posCount = 0;\r
-                               Demod.output[Demod.len] = 0xfb;\r
-                       }\r
-               }\r
-               else if(bit & 0x01) { Demod.syncBit = 0x01; }\r
-\r
-               if(Demod.syncBit) {\r
-                       Demod.len = 0;\r
-                       Demod.state = DEMOD_START_OF_COMMUNICATION;\r
-                       Demod.sub = SUB_FIRST_HALF;\r
-                       Demod.bitCount = 0;\r
-                       Demod.shiftReg = 0;\r
-                       Demod.parityBits = 0;\r
-                       Demod.samples = 0;\r
-                       if(Demod.posCount) {\r
-                               switch(Demod.syncBit) {\r
-                                       case 0x08: Demod.samples = 3; break;\r
-                                       case 0x04: Demod.samples = 2; break;\r
-                                       case 0x02: Demod.samples = 1; break;\r
-                                       case 0x01: Demod.samples = 0; break;\r
-                               }\r
-                       }\r
-                       error = 0;\r
-               }\r
-       }\r
-       else {\r
-               //modulation = bit & Demod.syncBit;\r
-               modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;\r
-\r
-               Demod.samples += 4;\r
-\r
-               if(Demod.posCount==0) {\r
-                       Demod.posCount = 1;\r
-                       if(modulation) {\r
-                               Demod.sub = SUB_FIRST_HALF;\r
-                       }\r
-                       else {\r
-                               Demod.sub = SUB_NONE;\r
-                       }\r
-               }\r
-               else {\r
-                       Demod.posCount = 0;\r
-                       if(modulation && (Demod.sub == SUB_FIRST_HALF)) {\r
-                               if(Demod.state!=DEMOD_ERROR_WAIT) {\r
-                                       Demod.state = DEMOD_ERROR_WAIT;\r
-                                       Demod.output[Demod.len] = 0xaa;\r
-                                       error = 0x01;\r
-                               }\r
-                       }\r
-                       else if(modulation) {\r
-                               Demod.sub = SUB_SECOND_HALF;\r
-                       }\r
-\r
-                       switch(Demod.state) {\r
-                               case DEMOD_START_OF_COMMUNICATION:\r
-                                       if(Demod.sub == SUB_FIRST_HALF) {\r
-                                               Demod.state = DEMOD_MANCHESTER_D;\r
-                                       }\r
-                                       else {\r
-                                               Demod.output[Demod.len] = 0xab;\r
-                                               Demod.state = DEMOD_ERROR_WAIT;\r
-                                               error = 0x02;\r
-                                       }\r
-                                       break;\r
-\r
-                               case DEMOD_MANCHESTER_D:\r
-                               case DEMOD_MANCHESTER_E:\r
-                                       if(Demod.sub == SUB_FIRST_HALF) {\r
-                                               Demod.bitCount++;\r
-                                               Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;\r
-                                               Demod.state = DEMOD_MANCHESTER_D;\r
-                                       }\r
-                                       else if(Demod.sub == SUB_SECOND_HALF) {\r
-                                               Demod.bitCount++;\r
-                                               Demod.shiftReg >>= 1;\r
-                                               Demod.state = DEMOD_MANCHESTER_E;\r
-                                       }\r
-                                       else {\r
-                                               Demod.state = DEMOD_MANCHESTER_F;\r
-                                       }\r
-                                       break;\r
-\r
-                               case DEMOD_MANCHESTER_F:\r
-                                       // Tag response does not need to be a complete byte!\r
-                                       if(Demod.len > 0 || Demod.bitCount > 0) {\r
-                                               if(Demod.bitCount > 0) {\r
-                                                       Demod.shiftReg >>= (9 - Demod.bitCount);\r
-                                                       Demod.output[Demod.len] = Demod.shiftReg & 0xff;\r
-                                                       Demod.len++;\r
-                                                       // No parity bit, so just shift a 0\r
-                                                       Demod.parityBits <<= 1;\r
-                                               }\r
-\r
-                                               Demod.state = DEMOD_UNSYNCD;\r
-                                               return TRUE;\r
-                                       }\r
-                                       else {\r
-                                               Demod.output[Demod.len] = 0xad;\r
-                                               Demod.state = DEMOD_ERROR_WAIT;\r
-                                               error = 0x03;\r
-                                       }\r
-                                       break;\r
-\r
-                               case DEMOD_ERROR_WAIT:\r
-                                       Demod.state = DEMOD_UNSYNCD;\r
-                                       break;\r
-\r
-                               default:\r
-                                       Demod.output[Demod.len] = 0xdd;\r
-                                       Demod.state = DEMOD_UNSYNCD;\r
-                                       break;\r
-                       }\r
-\r
-                       if(Demod.bitCount>=9) {\r
-                               Demod.output[Demod.len] = Demod.shiftReg & 0xff;\r
-                               Demod.len++;\r
-\r
-                               Demod.parityBits <<= 1;\r
-                               Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);\r
-\r
-                               Demod.bitCount = 0;\r
-                               Demod.shiftReg = 0;\r
-                       }\r
-\r
-                       /*if(error) {\r
-                               Demod.output[Demod.len] = 0xBB;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = error & 0xFF;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = 0xBB;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = bit & 0xFF;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = Demod.buffer & 0xFF;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = Demod.syncBit & 0xFF;\r
-                               Demod.len++;\r
-                               Demod.output[Demod.len] = 0xBB;\r
-                               Demod.len++;\r
-                               return TRUE;\r
-                       }*/\r
-\r
-               }\r
-\r
-       } // end (state != UNSYNCED)\r
-\r
-    return FALSE;\r
-}\r
-\r
-//=============================================================================\r
-// Finally, a `sniffer' for ISO 14443 Type A\r
-// Both sides of communication!\r
-//=============================================================================\r
-\r
-//-----------------------------------------------------------------------------\r
-// Record the sequence of commands sent by the reader to the tag, with\r
-// triggering so that we start recording at the point that the tag is moved\r
-// near the reader.\r
-//-----------------------------------------------------------------------------\r
-void SnoopIso14443a(void)\r
-{\r
-\r
-       // BIG CHANGE - UNDERSTAND THIS BEFORE WE COMMIT\r
-\r
-       #define RECV_CMD_OFFSET         3032\r
-       #define RECV_RES_OFFSET         3096\r
-       #define DMA_BUFFER_OFFSET       3160\r
-       #define DMA_BUFFER_SIZE         4096\r
-       #define TRACE_LENGTH            3000\r
-\r
-//     #define RECV_CMD_OFFSET         2032    // original (working as of 21/2/09) values\r
-//     #define RECV_RES_OFFSET         2096    // original (working as of 21/2/09) values\r
-//     #define DMA_BUFFER_OFFSET       2160    // original (working as of 21/2/09) values\r
-//     #define DMA_BUFFER_SIZE         4096    // original (working as of 21/2/09) values\r
-//     #define TRACE_LENGTH            2000    // original (working as of 21/2/09) values\r
-\r
-    // We won't start recording the frames that we acquire until we trigger;\r
-    // a good trigger condition to get started is probably when we see a\r
-    // response from the tag.\r
-    BOOL triggered = TRUE; // FALSE to wait first for card\r
-\r
-    // The command (reader -> tag) that we're receiving.\r
-       // The length of a received command will in most cases be no more than 18 bytes.\r
-       // So 32 should be enough!\r
-    BYTE *receivedCmd = (((BYTE *)BigBuf) + RECV_CMD_OFFSET);\r
-    // The response (tag -> reader) that we're receiving.\r
-    BYTE *receivedResponse = (((BYTE *)BigBuf) + RECV_RES_OFFSET);\r
-\r
-    // As we receive stuff, we copy it from receivedCmd or receivedResponse\r
-    // into trace, along with its length and other annotations.\r
-    //BYTE *trace = (BYTE *)BigBuf;\r
-    //int traceLen = 0;\r
-\r
-    // The DMA buffer, used to stream samples from the FPGA\r
-    SBYTE *dmaBuf = ((SBYTE *)BigBuf) + DMA_BUFFER_OFFSET;\r
-    int lastRxCounter;\r
-    SBYTE *upTo;\r
-    int smpl;\r
-    int maxBehindBy = 0;\r
-\r
-    // Count of samples received so far, so that we can include timing\r
-    // information in the trace buffer.\r
-    int samples = 0;\r
-       int rsamples = 0;\r
-\r
-    memset(trace, 0x44, RECV_CMD_OFFSET);\r
-\r
-    // Set up the demodulator for tag -> reader responses.\r
-    Demod.output = receivedResponse;\r
-    Demod.len = 0;\r
-    Demod.state = DEMOD_UNSYNCD;\r
-\r
-    // And the reader -> tag commands\r
-    memset(&Uart, 0, sizeof(Uart));\r
-    Uart.output = receivedCmd;\r
-    Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////\r
-    Uart.state = STATE_UNSYNCD;\r
-\r
-    // And put the FPGA in the appropriate mode\r
-    // Signal field is off with the appropriate LED\r
-    LED_D_OFF();\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);\r
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-\r
-       // Setup for the DMA.\r
-    FpgaSetupSsc();\r
-    upTo = dmaBuf;\r
-    lastRxCounter = DMA_BUFFER_SIZE;\r
-    FpgaSetupSscDma((BYTE *)dmaBuf, DMA_BUFFER_SIZE);\r
-\r
-    LED_A_ON();\r
-\r
-    // And now we loop, receiving samples.\r
-    for(;;) {\r
-               WDT_HIT();\r
-        int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &\r
-                                (DMA_BUFFER_SIZE-1);\r
-        if(behindBy > maxBehindBy) {\r
-            maxBehindBy = behindBy;\r
-            if(behindBy > 400) {\r
-                DbpString("blew circular buffer!");\r
-                goto done;\r
-            }\r
-        }\r
-        if(behindBy < 1) continue;\r
-\r
-        smpl = upTo[0];\r
-        upTo++;\r
-        lastRxCounter -= 1;\r
-        if(upTo - dmaBuf > DMA_BUFFER_SIZE) {\r
-            upTo -= DMA_BUFFER_SIZE;\r
-            lastRxCounter += DMA_BUFFER_SIZE;\r
-            AT91C_BASE_PDC_SSC->PDC_RNPR = (DWORD)upTo;\r
-            AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;\r
-        }\r
-\r
-        samples += 4;\r
-#define HANDLE_BIT_IF_BODY \\r
-            LED_C_ON(); \\r
-                       if(triggered) { \\r
-                               trace[traceLen++] = ((rsamples >>  0) & 0xff); \\r
-                trace[traceLen++] = ((rsamples >>  8) & 0xff); \\r
-                trace[traceLen++] = ((rsamples >> 16) & 0xff); \\r
-                trace[traceLen++] = ((rsamples >> 24) & 0xff); \\r
-                               trace[traceLen++] = ((Uart.parityBits >>  0) & 0xff); \\r
-                               trace[traceLen++] = ((Uart.parityBits >>  8) & 0xff); \\r
-                               trace[traceLen++] = ((Uart.parityBits >> 16) & 0xff); \\r
-                               trace[traceLen++] = ((Uart.parityBits >> 24) & 0xff); \\r
-                trace[traceLen++] = Uart.byteCnt; \\r
-                memcpy(trace+traceLen, receivedCmd, Uart.byteCnt); \\r
-                traceLen += Uart.byteCnt; \\r
-                if(traceLen > TRACE_LENGTH) break; \\r
-            } \\r
-            /* And ready to receive another command. */ \\r
-            Uart.state = STATE_UNSYNCD; \\r
-            /* And also reset the demod code, which might have been */ \\r
-            /* false-triggered by the commands from the reader. */ \\r
-            Demod.state = DEMOD_UNSYNCD; \\r
-                       LED_B_OFF(); \\r
-\r
-               if(MillerDecoding((smpl & 0xF0) >> 4)) {\r
-            rsamples = samples - Uart.samples;\r
-                       HANDLE_BIT_IF_BODY\r
-        }\r
-               if(ManchesterDecoding(smpl & 0x0F)) {\r
-                       rsamples = samples - Demod.samples;\r
-                       LED_B_ON();\r
-\r
-                       // timestamp, as a count of samples\r
-                       trace[traceLen++] = ((rsamples >>  0) & 0xff);\r
-                       trace[traceLen++] = ((rsamples >>  8) & 0xff);\r
-                       trace[traceLen++] = ((rsamples >> 16) & 0xff);\r
-                       trace[traceLen++] = 0x80 | ((rsamples >> 24) & 0xff);\r
-                       trace[traceLen++] = ((Demod.parityBits >>  0) & 0xff);\r
-                       trace[traceLen++] = ((Demod.parityBits >>  8) & 0xff);\r
-                       trace[traceLen++] = ((Demod.parityBits >> 16) & 0xff);\r
-                       trace[traceLen++] = ((Demod.parityBits >> 24) & 0xff);\r
-                       // length\r
-                       trace[traceLen++] = Demod.len;\r
-                       memcpy(trace+traceLen, receivedResponse, Demod.len);\r
-                       traceLen += Demod.len;\r
-                       if(traceLen > TRACE_LENGTH) break;\r
-\r
-               triggered = TRUE;\r
-\r
-            // And ready to receive another response.\r
-            memset(&Demod, 0, sizeof(Demod));\r
-            Demod.output = receivedResponse;\r
-            Demod.state = DEMOD_UNSYNCD;\r
-                       LED_C_OFF();\r
-               }\r
-\r
-        if(BUTTON_PRESS()) {\r
-            DbpString("cancelled_a");\r
-            goto done;\r
-        }\r
-    }\r
-\r
-    DbpString("COMMAND FINISHED");\r
-\r
-    DbpIntegers(maxBehindBy, Uart.state, Uart.byteCnt);\r
-    DbpIntegers(Uart.byteCntMax, traceLen, (int)Uart.output[0]);\r
-\r
-done:\r
-    AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;\r
-    DbpIntegers(maxBehindBy, Uart.state, Uart.byteCnt);\r
-    DbpIntegers(Uart.byteCntMax, traceLen, (int)Uart.output[0]);\r
-    LED_A_OFF();\r
-    LED_B_OFF();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-}\r
-\r
-// Prepare communication bits to send to FPGA\r
-void Sequence(SecType seq)\r
-{\r
-       ToSendMax++;\r
-       switch(seq) {\r
-       // CARD TO READER\r
-       case SEC_D:\r
-               // Sequence D: 11110000\r
-               // modulation with subcarrier during first half\r
-        ToSend[ToSendMax] = 0xf0;\r
-               break;\r
-       case SEC_E:\r
-               // Sequence E: 00001111\r
-               // modulation with subcarrier during second half\r
-        ToSend[ToSendMax] = 0x0f;\r
-               break;\r
-       case SEC_F:\r
-               // Sequence F: 00000000\r
-               // no modulation with subcarrier\r
-        ToSend[ToSendMax] = 0x00;\r
-               break;\r
-       // READER TO CARD\r
-       case SEC_X:\r
-               // Sequence X: 00001100\r
-               // drop after half a period\r
-        ToSend[ToSendMax] = 0x0c;\r
-               break;\r
-       case SEC_Y:\r
-       default:\r
-               // Sequence Y: 00000000\r
-               // no drop\r
-        ToSend[ToSendMax] = 0x00;\r
-               break;\r
-       case SEC_Z:\r
-               // Sequence Z: 11000000\r
-               // drop at start\r
-        ToSend[ToSendMax] = 0xc0;\r
-               break;\r
-       }\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Prepare tag messages\r
-//-----------------------------------------------------------------------------\r
-static void CodeIso14443aAsTag(const BYTE *cmd, int len)\r
-{\r
-    int i;\r
-       int oddparity;\r
-\r
-    ToSendReset();\r
-\r
-       // Correction bit, might be removed when not needed\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(1);  // 1\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-\r
-       // Send startbit\r
-       Sequence(SEC_D);\r
-\r
-    for(i = 0; i < len; i++) {\r
-        int j;\r
-        BYTE b = cmd[i];\r
-\r
-               // Data bits\r
-        oddparity = 0x01;\r
-               for(j = 0; j < 8; j++) {\r
-            oddparity ^= (b & 1);\r
-                       if(b & 1) {\r
-                               Sequence(SEC_D);\r
-                       } else {\r
-                               Sequence(SEC_E);\r
-            }\r
-            b >>= 1;\r
-        }\r
-\r
-        // Parity bit\r
-        if(oddparity) {\r
-                       Sequence(SEC_D);\r
-               } else {\r
-                       Sequence(SEC_E);\r
-               }\r
-    }\r
-\r
-    // Send stopbit\r
-       Sequence(SEC_F);\r
-\r
-       // Flush the buffer in FPGA!!\r
-       for(i = 0; i < 5; i++) {\r
-               Sequence(SEC_F);\r
-       }\r
-\r
-    // Convert from last byte pos to length\r
-    ToSendMax++;\r
-\r
-    // Add a few more for slop\r
-    ToSend[ToSendMax++] = 0x00;\r
-       ToSend[ToSendMax++] = 0x00;\r
-    //ToSendMax += 2;\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// This is to send a NACK kind of answer, its only 3 bits, I know it should be 4\r
-//-----------------------------------------------------------------------------\r
-static void CodeStrangeAnswer()\r
-{\r
-       int i;\r
-\r
-    ToSendReset();\r
-\r
-       // Correction bit, might be removed when not needed\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(1);  // 1\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(0);\r
-\r
-       // Send startbit\r
-       Sequence(SEC_D);\r
-\r
-       // 0\r
-       Sequence(SEC_E);\r
-\r
-       // 0\r
-       Sequence(SEC_E);\r
-\r
-       // 1\r
-       Sequence(SEC_D);\r
-\r
-    // Send stopbit\r
-       Sequence(SEC_F);\r
-\r
-       // Flush the buffer in FPGA!!\r
-       for(i = 0; i < 5; i++) {\r
-               Sequence(SEC_F);\r
-       }\r
-\r
-    // Convert from last byte pos to length\r
-    ToSendMax++;\r
-\r
-    // Add a few more for slop\r
-    ToSend[ToSendMax++] = 0x00;\r
-       ToSend[ToSendMax++] = 0x00;\r
-    //ToSendMax += 2;\r
-}\r
-\r
-int LogTrace(const BYTE * btBytes, int iLen, int iSamples, DWORD dwParity, BOOL bReader)\r
-{\r
-  // Trace the random, i'm curious\r
-  rsamples += iSamples;\r
-  trace[traceLen++] = ((rsamples >> 0) & 0xff);\r
-  trace[traceLen++] = ((rsamples >> 8) & 0xff);\r
-  trace[traceLen++] = ((rsamples >> 16) & 0xff);\r
-  trace[traceLen++] = ((rsamples >> 24) & 0xff);\r
-  if (!bReader) {\r
-    trace[traceLen - 1] |= 0x80;\r
-  }\r
-  trace[traceLen++] = ((dwParity >> 0) & 0xff);\r
-  trace[traceLen++] = ((dwParity >> 8) & 0xff);\r
-  trace[traceLen++] = ((dwParity >> 16) & 0xff);\r
-  trace[traceLen++] = ((dwParity >> 24) & 0xff);\r
-  trace[traceLen++] = iLen;\r
-  memcpy(trace + traceLen, btBytes, iLen);\r
-  traceLen += iLen;\r
-  return (traceLen < TRACE_LENGTH);\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Wait for commands from reader\r
-// Stop when button is pressed\r
-// Or return TRUE when command is captured\r
-//-----------------------------------------------------------------------------\r
-static BOOL GetIso14443aCommandFromReader(BYTE *received, int *len, int maxLen)\r
-{\r
-    // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen\r
-    // only, since we are receiving, not transmitting).\r
-    // Signal field is off with the appropriate LED\r
-    LED_D_OFF();\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);\r
-\r
-    // Now run a `software UART' on the stream of incoming samples.\r
-    Uart.output = received;\r
-    Uart.byteCntMax = maxLen;\r
-    Uart.state = STATE_UNSYNCD;\r
-\r
-    for(;;) {\r
-        WDT_HIT();\r
-\r
-        if(BUTTON_PRESS()) return FALSE;\r
-\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {\r
-            AT91C_BASE_SSC->SSC_THR = 0x00;\r
-        }\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {\r
-            BYTE b = (BYTE)AT91C_BASE_SSC->SSC_RHR;\r
-                       if(MillerDecoding((b & 0xf0) >> 4)) {\r
-                               *len = Uart.byteCnt;\r
-                               return TRUE;\r
-                       }\r
-                       if(MillerDecoding(b & 0x0f)) {\r
-                               *len = Uart.byteCnt;\r
-                               return TRUE;\r
-                       }\r
-        }\r
-    }\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Main loop of simulated tag: receive commands from reader, decide what\r
-// response to send, and send it.\r
-//-----------------------------------------------------------------------------\r
-void SimulateIso14443aTag(int tagType, int TagUid)\r
-{\r
-       // This function contains the tag emulation\r
-\r
-       // Prepare protocol messages\r
-    // static const BYTE cmd1[] = { 0x26 };\r
-//     static const BYTE response1[] = { 0x02, 0x00 }; // Says: I am Mifare 4k - original line - greg\r
-//\r
-       static const BYTE response1[] = { 0x44, 0x03 }; // Says: I am a DESFire Tag, ph33r me\r
-//     static const BYTE response1[] = { 0x44, 0x00 }; // Says: I am a ULTRALITE Tag, 0wn me\r
-\r
-       // UID response\r
-    // static const BYTE cmd2[] = { 0x93, 0x20 };\r
-    //static const BYTE response2[] = { 0x9a, 0xe5, 0xe4, 0x43, 0xd8 }; // original value - greg\r
-\r
-\r
-\r
-// my desfire\r
-    static const BYTE response2[] = { 0x88, 0x04, 0x21, 0x3f, 0x4d }; // known uid - note cascade (0x88), 2nd byte (0x04) = NXP/Phillips\r
-\r
-\r
-// When reader selects us during cascade1 it will send cmd3\r
-//BYTE response3[] = { 0x04, 0x00, 0x00 }; // SAK Select (cascade1) successful response (ULTRALITE)\r
-BYTE response3[] = { 0x24, 0x00, 0x00 }; // SAK Select (cascade1) successful response (DESFire)\r
-ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);\r
-\r
-// send cascade2 2nd half of UID\r
-static const BYTE response2a[] = { 0x51, 0x48, 0x1d, 0x80, 0x84 }; //  uid - cascade2 - 2nd half (4 bytes) of UID+ BCCheck\r
-// NOTE : THE CRC on the above may be wrong as I have obfuscated the actual UID\r
-\r
-\r
-// When reader selects us during cascade2 it will send cmd3a\r
-//BYTE response3a[] = { 0x00, 0x00, 0x00 }; // SAK Select (cascade2) successful response (ULTRALITE)\r
-BYTE response3a[] = { 0x20, 0x00, 0x00 }; // SAK Select (cascade2) successful response (DESFire)\r
-ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);\r
-\r
-    static const BYTE response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce\r
-\r
-    BYTE *resp;\r
-    int respLen;\r
-\r
-    // Longest possible response will be 16 bytes + 2 CRC = 18 bytes\r
-       // This will need\r
-       //    144        data bits (18 * 8)\r
-       //     18        parity bits\r
-       //      2        Start and stop\r
-       //      1        Correction bit (Answer in 1172 or 1236 periods, see FPGA)\r
-       //      1        just for the case\r
-       // ----------- +\r
-       //    166\r
-       //\r
-       // 166 bytes, since every bit that needs to be send costs us a byte\r
-       //\r
-\r
-\r
-    // Respond with card type\r
-    BYTE *resp1 = (((BYTE *)BigBuf) + 800);\r
-    int resp1Len;\r
-\r
-    // Anticollision cascade1 - respond with uid\r
-    BYTE *resp2 = (((BYTE *)BigBuf) + 970);\r
-    int resp2Len;\r
-\r
-    // Anticollision cascade2 - respond with 2nd half of uid if asked\r
-    // we're only going to be asked if we set the 1st byte of the UID (during cascade1) to 0x88\r
-    BYTE *resp2a = (((BYTE *)BigBuf) + 1140);\r
-    int resp2aLen;\r
-\r
-    // Acknowledge select - cascade 1\r
-    BYTE *resp3 = (((BYTE *)BigBuf) + 1310);\r
-    int resp3Len;\r
-\r
-    // Acknowledge select - cascade 2\r
-    BYTE *resp3a = (((BYTE *)BigBuf) + 1480);\r
-    int resp3aLen;\r
-\r
-    // Response to a read request - not implemented atm\r
-    BYTE *resp4 = (((BYTE *)BigBuf) + 1550);\r
-    int resp4Len;\r
-\r
-    // Authenticate response - nonce\r
-    BYTE *resp5 = (((BYTE *)BigBuf) + 1720);\r
-    int resp5Len;\r
-\r
-    BYTE *receivedCmd = (BYTE *)BigBuf;\r
-    int len;\r
-\r
-    int i;\r
-       int u;\r
-       BYTE b;\r
-\r
-       // To control where we are in the protocol\r
-       int order = 0;\r
-       int lastorder;\r
-\r
-       // Just to allow some checks\r
-       int happened = 0;\r
-       int happened2 = 0;\r
-\r
-    int cmdsRecvd = 0;\r
-\r
-       BOOL fdt_indicator;\r
-\r
-    memset(receivedCmd, 0x44, 400);\r
-\r
-       // Prepare the responses of the anticollision phase\r
-       // there will be not enough time to do this at the moment the reader sends it REQA\r
-\r
-       // Answer to request\r
-       CodeIso14443aAsTag(response1, sizeof(response1));\r
-    memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;\r
-\r
-       // Send our UID (cascade 1)\r
-       CodeIso14443aAsTag(response2, sizeof(response2));\r
-    memcpy(resp2, ToSend, ToSendMax); resp2Len = ToSendMax;\r
-\r
-       // Answer to select (cascade1)\r
-       CodeIso14443aAsTag(response3, sizeof(response3));\r
-    memcpy(resp3, ToSend, ToSendMax); resp3Len = ToSendMax;\r
-\r
-       // Send the cascade 2 2nd part of the uid\r
-       CodeIso14443aAsTag(response2a, sizeof(response2a));\r
-    memcpy(resp2a, ToSend, ToSendMax); resp2aLen = ToSendMax;\r
-\r
-       // Answer to select (cascade 2)\r
-       CodeIso14443aAsTag(response3a, sizeof(response3a));\r
-    memcpy(resp3a, ToSend, ToSendMax); resp3aLen = ToSendMax;\r
-\r
-       // Strange answer is an example of rare message size (3 bits)\r
-       CodeStrangeAnswer();\r
-       memcpy(resp4, ToSend, ToSendMax); resp4Len = ToSendMax;\r
-\r
-       // Authentication answer (random nonce)\r
-       CodeIso14443aAsTag(response5, sizeof(response5));\r
-    memcpy(resp5, ToSend, ToSendMax); resp5Len = ToSendMax;\r
-\r
-    // We need to listen to the high-frequency, peak-detected path.\r
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-    FpgaSetupSsc();\r
-\r
-    cmdsRecvd = 0;\r
-\r
-    LED_A_ON();\r
-       for(;;) {\r
-\r
-               if(!GetIso14443aCommandFromReader(receivedCmd, &len, 100)) {\r
-            DbpString("button press");\r
-            break;\r
-        }\r
-       // doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated\r
-        // Okay, look at the command now.\r
-        lastorder = order;\r
-               i = 1; // first byte transmitted\r
-        if(receivedCmd[0] == 0x26) {\r
-                       // Received a REQUEST\r
-                       resp = resp1; respLen = resp1Len; order = 1;\r
-                       //DbpString("Hello request from reader:");\r
-               } else if(receivedCmd[0] == 0x52) {\r
-                       // Received a WAKEUP\r
-                       resp = resp1; respLen = resp1Len; order = 6;\r
-//                     //DbpString("Wakeup request from reader:");\r
-\r
-               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) {   // greg - cascade 1 anti-collision\r
-                       // Received request for UID (cascade 1)\r
-                       resp = resp2; respLen = resp2Len; order = 2;\r
-//                     DbpString("UID (cascade 1) request from reader:");\r
-//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-\r
-               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] ==0x95) {    // greg - cascade 2 anti-collision\r
-                       // Received request for UID (cascade 2)\r
-                       resp = resp2a; respLen = resp2aLen; order = 20;\r
-//                     DbpString("UID (cascade 2) request from reader:");\r
-//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-\r
-               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x93) {    // greg - cascade 1 select\r
-                       // Received a SELECT\r
-                       resp = resp3; respLen = resp3Len; order = 3;\r
-//                     DbpString("Select (cascade 1) request from reader:");\r
-//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-\r
-               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x95) {    // greg - cascade 2 select\r
-                       // Received a SELECT\r
-                       resp = resp3a; respLen = resp3aLen; order = 30;\r
-//                     DbpString("Select (cascade 2) request from reader:");\r
-//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-\r
-               } else if(receivedCmd[0] == 0x30) {\r
-                       // Received a READ\r
-                       resp = resp4; respLen = resp4Len; order = 4; // Do nothing\r
-                       DbpString("Read request from reader:");\r
-                       DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-\r
-               } else if(receivedCmd[0] == 0x50) {\r
-                       // Received a HALT\r
-                       resp = resp1; respLen = 0; order = 5; // Do nothing\r
-                       DbpString("Reader requested we HALT!:");\r
-\r
-               } else if(receivedCmd[0] == 0x60) {\r
-                       // Received an authentication request\r
-                       resp = resp5; respLen = resp5Len; order = 7;\r
-                       DbpString("Authenticate request from reader:");\r
-                       DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-\r
-               } else if(receivedCmd[0] == 0xE0) {\r
-                       // Received a RATS request\r
-                       resp = resp1; respLen = 0;order = 70;\r
-                       DbpString("RATS request from reader:");\r
-                       DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-        } else {\r
-            // Never seen this command before\r
-                       DbpString("Unknown command received from reader:");\r
-                       DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);\r
-                       DbpIntegers(receivedCmd[3], receivedCmd[4], receivedCmd[5]);\r
-                       DbpIntegers(receivedCmd[6], receivedCmd[7], receivedCmd[8]);\r
-\r
-                       // Do not respond\r
-                       resp = resp1; respLen = 0; order = 0;\r
-        }\r
-\r
-               // Count number of wakeups received after a halt\r
-               if(order == 6 && lastorder == 5) { happened++; }\r
-\r
-               // Count number of other messages after a halt\r
-               if(order != 6 && lastorder == 5) { happened2++; }\r
-\r
-               // Look at last parity bit to determine timing of answer\r
-               if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) {\r
-                       // 1236, so correction bit needed\r
-                       i = 0;\r
-               }\r
-\r
-        memset(receivedCmd, 0x44, 32);\r
-\r
-               if(cmdsRecvd > 999) {\r
-                       DbpString("1000 commands later...");\r
-            break;\r
-        }\r
-               else {\r
-                       cmdsRecvd++;\r
-               }\r
-\r
-        if(respLen <= 0) continue;\r
-\r
-        // Modulate Manchester\r
-               FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);\r
-        AT91C_BASE_SSC->SSC_THR = 0x00;\r
-        FpgaSetupSsc();\r
-\r
-               // ### Transmit the response ###\r
-               u = 0;\r
-               b = 0x00;\r
-               fdt_indicator = FALSE;\r
-        for(;;) {\r
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {\r
-                               volatile BYTE b = (BYTE)AT91C_BASE_SSC->SSC_RHR;\r
-                (void)b;\r
-            }\r
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {\r
-                               if(i > respLen) {\r
-                                       b = 0x00;\r
-                                       u++;\r
-                               } else {\r
-                                       b = resp[i];\r
-                                       i++;\r
-                               }\r
-                               AT91C_BASE_SSC->SSC_THR = b;\r
-\r
-                if(u > 4) {\r
-                    break;\r
-                }\r
-            }\r
-                       if(BUTTON_PRESS()) {\r
-                           break;\r
-                       }\r
-        }\r
-\r
-    }\r
-\r
-       DbpIntegers(happened, happened2, cmdsRecvd);\r
-       LED_A_OFF();\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Transmit the command (to the tag) that was placed in ToSend[].\r
-//-----------------------------------------------------------------------------\r
-static void TransmitFor14443a(const BYTE *cmd, int len, int *samples, int *wait)\r
-{\r
-    int c;\r
-\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);\r
-\r
-       if(*wait < 10) { *wait = 10; }\r
-\r
-    for(c = 0; c < *wait;) {\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {\r
-            AT91C_BASE_SSC->SSC_THR = 0x00;            // For exact timing!\r
-            c++;\r
-        }\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {\r
-            volatile DWORD r = AT91C_BASE_SSC->SSC_RHR;\r
-            (void)r;\r
-        }\r
-        WDT_HIT();\r
-    }\r
-\r
-    c = 0;\r
-    for(;;) {\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {\r
-            AT91C_BASE_SSC->SSC_THR = cmd[c];\r
-            c++;\r
-            if(c >= len) {\r
-                break;\r
-            }\r
-        }\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {\r
-            volatile DWORD r = AT91C_BASE_SSC->SSC_RHR;\r
-            (void)r;\r
-        }\r
-        WDT_HIT();\r
-    }\r
-       *samples = (c + *wait) << 3;\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// To generate an arbitrary stream from reader\r
-//\r
-//-----------------------------------------------------------------------------\r
-void ArbitraryFromReader(const BYTE *cmd, int parity, int len)\r
-{\r
-       int i;\r
-       int j;\r
-       int last;\r
-    BYTE b;\r
-\r
-       ToSendReset();\r
-\r
-       // Start of Communication (Seq. Z)\r
-       Sequence(SEC_Z);\r
-       last = 0;\r
-\r
-       for(i = 0; i < len; i++) {\r
-        // Data bits\r
-        b = cmd[i];\r
-               for(j = 0; j < 8; j++) {\r
-                       if(b & 1) {\r
-                               // Sequence X\r
-                               Sequence(SEC_X);\r
-                               last = 1;\r
-                       } else {\r
-                               if(last == 0) {\r
-                                       // Sequence Z\r
-                                       Sequence(SEC_Z);\r
-                               }\r
-                               else {\r
-                                       // Sequence Y\r
-                                       Sequence(SEC_Y);\r
-                                       last = 0;\r
-                               }\r
-                       }\r
-                       b >>= 1;\r
-\r
-               }\r
-\r
-               // Predefined parity bit, the flipper flips when needed, because of flips in byte sent\r
-               if(((parity >> (len - i - 1)) & 1)) {\r
-                       // Sequence X\r
-                       Sequence(SEC_X);\r
-                       last = 1;\r
-               } else {\r
-                       if(last == 0) {\r
-                               // Sequence Z\r
-                               Sequence(SEC_Z);\r
-                       }\r
-                       else {\r
-                               // Sequence Y\r
-                               Sequence(SEC_Y);\r
-                               last = 0;\r
-                       }\r
-               }\r
-       }\r
-\r
-       // End of Communication\r
-       if(last == 0) {\r
-               // Sequence Z\r
-               Sequence(SEC_Z);\r
-       }\r
-       else {\r
-               // Sequence Y\r
-               Sequence(SEC_Y);\r
-               last = 0;\r
-       }\r
-       // Sequence Y\r
-       Sequence(SEC_Y);\r
-\r
-       // Just to be sure!\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-\r
-    // Convert from last character reference to length\r
-    ToSendMax++;\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Code a 7-bit command without parity bit\r
-// This is especially for 0x26 and 0x52 (REQA and WUPA)\r
-//-----------------------------------------------------------------------------\r
-void ShortFrameFromReader(const BYTE *cmd)\r
-{\r
-       int j;\r
-       int last;\r
-    BYTE b;\r
-\r
-       ToSendReset();\r
-\r
-       // Start of Communication (Seq. Z)\r
-       Sequence(SEC_Z);\r
-       last = 0;\r
-\r
-       b = cmd[0];\r
-       for(j = 0; j < 7; j++) {\r
-               if(b & 1) {\r
-                       // Sequence X\r
-                       Sequence(SEC_X);\r
-                       last = 1;\r
-               } else {\r
-                       if(last == 0) {\r
-                               // Sequence Z\r
-                               Sequence(SEC_Z);\r
-                       }\r
-                       else {\r
-                               // Sequence Y\r
-                               Sequence(SEC_Y);\r
-                               last = 0;\r
-                       }\r
-               }\r
-               b >>= 1;\r
-       }\r
-\r
-       // End of Communication\r
-       if(last == 0) {\r
-               // Sequence Z\r
-               Sequence(SEC_Z);\r
-       }\r
-       else {\r
-               // Sequence Y\r
-               Sequence(SEC_Y);\r
-               last = 0;\r
-       }\r
-       // Sequence Y\r
-       Sequence(SEC_Y);\r
-\r
-       // Just to be sure!\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-\r
-    // Convert from last character reference to length\r
-    ToSendMax++;\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// Prepare reader command to send to FPGA\r
-//\r
-//-----------------------------------------------------------------------------\r
-void CodeIso14443aAsReader(const BYTE *cmd, int len)\r
-{\r
-    int i, j;\r
-       int last;\r
-       int oddparity;\r
-    BYTE b;\r
-\r
-    ToSendReset();\r
-\r
-       // Start of Communication (Seq. Z)\r
-       Sequence(SEC_Z);\r
-       last = 0;\r
-\r
-       for(i = 0; i < len; i++) {\r
-        // Data bits\r
-        b = cmd[i];\r
-        oddparity = 0x01;\r
-        for(j = 0; j < 8; j++) {\r
-            oddparity ^= (b & 1);\r
-            if(b & 1) {\r
-                               // Sequence X\r
-                               Sequence(SEC_X);\r
-                               last = 1;\r
-            } else {\r
-                if(last == 0) {\r
-                                       // Sequence Z\r
-                                       Sequence(SEC_Z);\r
-                               }\r
-                               else {\r
-                                       // Sequence Y\r
-                                       Sequence(SEC_Y);\r
-                                       last = 0;\r
-                               }\r
-            }\r
-            b >>= 1;\r
-        }\r
-\r
-               // Parity bit\r
-               if(oddparity) {\r
-                       // Sequence X\r
-                       Sequence(SEC_X);\r
-                       last = 1;\r
-               } else {\r
-                       if(last == 0) {\r
-                               // Sequence Z\r
-                               Sequence(SEC_Z);\r
-                       }\r
-                       else {\r
-                               // Sequence Y\r
-                               Sequence(SEC_Y);\r
-                               last = 0;\r
-                       }\r
-               }\r
-    }\r
-\r
-       // End of Communication\r
-       if(last == 0) {\r
-               // Sequence Z\r
-               Sequence(SEC_Z);\r
-       }\r
-       else {\r
-               // Sequence Y\r
-               Sequence(SEC_Y);\r
-               last = 0;\r
-       }\r
-       // Sequence Y\r
-       Sequence(SEC_Y);\r
-\r
-       // Just to be sure!\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-       Sequence(SEC_Y);\r
-\r
-    // Convert from last character reference to length\r
-    ToSendMax++;\r
-}\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Wait a certain time for tag response\r
-//  If a response is captured return TRUE\r
-//  If it takes to long return FALSE\r
-//-----------------------------------------------------------------------------\r
-static BOOL GetIso14443aAnswerFromTag(BYTE *receivedResponse, int maxLen, int *samples, int *elapsed) //BYTE *buffer\r
-{\r
-       // buffer needs to be 512 bytes\r
-       int c;\r
-\r
-       // Set FPGA mode to "reader listen mode", no modulation (listen\r
-    // only, since we are receiving, not transmitting).\r
-    // Signal field is on with the appropriate LED\r
-    LED_D_ON();\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);\r
-\r
-    // Now get the answer from the card\r
-    Demod.output = receivedResponse;\r
-    Demod.len = 0;\r
-    Demod.state = DEMOD_UNSYNCD;\r
-\r
-       BYTE b;\r
-       *elapsed = 0;\r
-\r
-       c = 0;\r
-       for(;;) {\r
-        WDT_HIT();\r
-\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {\r
-            AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!\r
-                       (*elapsed)++;\r
-        }\r
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {\r
-                       if(c < 512) { c++; } else { return FALSE; }\r
-            b = (BYTE)AT91C_BASE_SSC->SSC_RHR;\r
-                       if(ManchesterDecoding((b & 0xf0) >> 4)) {\r
-                               *samples = ((c - 1) << 3) + 4;\r
-                               return TRUE;\r
-                       }\r
-                       if(ManchesterDecoding(b & 0x0f)) {\r
-                               *samples = c << 3;\r
-                               return TRUE;\r
-                       }\r
-        }\r
-    }\r
-}\r
-\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Read an ISO 14443a tag. Send out commands and store answers.\r
-//\r
-//-----------------------------------------------------------------------------\r
-void ReaderIso14443a(DWORD parameter)\r
-{\r
-       // Anticollision\r
-       static const BYTE cmd1[]       = { 0x52 }; // or 0x26\r
-       static const BYTE cmd2[]       = { 0x93,0x20 };\r
-       // UID = 0x2a,0x69,0x8d,0x43,0x8d, last two bytes are CRC bytes\r
-       BYTE cmd3[] = { 0x93,0x70,0x2a,0x69,0x8d,0x43,0x8d,0x52,0x55 };\r
-\r
-       // For Ultralight add an extra anticollission layer -> 95 20 and then 95 70\r
-\r
-       // greg - here we will add our cascade level 2 anticolission and select functions to deal with ultralight               // and 7-byte UIDs in generall...\r
-       BYTE cmd4[] = {0x95,0x20};      // ask for cascade 2 select\r
-       // 95 20\r
-       //BYTE cmd3a[] = { 0x95,0x70,0x2a,0x69,0x8d,0x43,0x8d,0x52,0x55 };\r
-       // 95 70\r
-\r
-       // cascade 2 select\r
-       BYTE cmd5[] = { 0x95,0x70,0x2a,0x69,0x8d,0x43,0x8d,0x52,0x55 };\r
-\r
-\r
-       // RATS (request for answer to select)\r
-       //BYTE cmd6[] = { 0xe0,0x50,0xbc,0xa5 };  // original RATS\r
-       BYTE cmd6[] = { 0xe0,0x21,0xb2,0xc7 };  // Desfire RATS\r
-\r
-       // Mifare AUTH\r
-       BYTE cmd7[] = { 0x60, 0x00, 0x00, 0x00 };\r
-\r
-       int reqaddr = 2024;                                     // was 2024 - tied to other size changes\r
-       int reqsize = 60;\r
-\r
-       BYTE *req1 = (((BYTE *)BigBuf) + reqaddr);\r
-    int req1Len;\r
-\r
-    BYTE *req2 = (((BYTE *)BigBuf) + reqaddr + reqsize);\r
-    int req2Len;\r
-\r
-    BYTE *req3 = (((BYTE *)BigBuf) + reqaddr + (reqsize * 2));\r
-    int req3Len;\r
-\r
-// greg added req 4 & 5 to deal with cascade 2 section\r
-    BYTE *req4 = (((BYTE *)BigBuf) + reqaddr + (reqsize * 3));\r
-    int req4Len;\r
-\r
-    BYTE *req5 = (((BYTE *)BigBuf) + reqaddr + (reqsize * 4));\r
-    int req5Len;\r
-\r
-    BYTE *req6 = (((BYTE *)BigBuf) + reqaddr + (reqsize * 5));\r
-    int req6Len;\r
-\r
-    BYTE *req7 = (((BYTE *)BigBuf) + reqaddr + (reqsize * 6));\r
-    int req7Len;\r
-\r
-       BYTE *receivedAnswer = (((BYTE *)BigBuf) + 3560);       // was 3560 - tied to other size changes\r
-\r
-       //BYTE *trace = (BYTE *)BigBuf;\r
-       //int traceLen = 0;\r
-       //int rsamples = 0;\r
-  traceLen = 0;\r
-\r
-       memset(trace, 0x44, 2000);                              // was 2000 - tied to oter size chnages\r
-       // setting it to 3000 causes no tag responses to be detected (2900 is ok)\r
-       // setting it to 1000 causes no tag responses to be detected\r
-\r
-       // Prepare some commands!\r
-    ShortFrameFromReader(cmd1);\r
-    memcpy(req1, ToSend, ToSendMax); req1Len = ToSendMax;\r
-\r
-       CodeIso14443aAsReader(cmd2, sizeof(cmd2));\r
-    memcpy(req2, ToSend, ToSendMax); req2Len = ToSendMax;\r
-\r
-       CodeIso14443aAsReader(cmd3, sizeof(cmd3));\r
-    memcpy(req3, ToSend, ToSendMax); req3Len = ToSendMax;\r
-\r
-\r
-       CodeIso14443aAsReader(cmd4, sizeof(cmd4));              // 4 is cascade 2 request\r
-    memcpy(req4, ToSend, ToSendMax); req4Len = ToSendMax;\r
-\r
-\r
-       CodeIso14443aAsReader(cmd5, sizeof(cmd5));      // 5 is cascade 2 select\r
-    memcpy(req5, ToSend, ToSendMax); req5Len = ToSendMax;\r
-\r
-\r
-       CodeIso14443aAsReader(cmd6, sizeof(cmd6));\r
-    memcpy(req6, ToSend, ToSendMax); req6Len = ToSendMax;\r
-\r
-       // Setup SSC\r
-       FpgaSetupSsc();\r
-\r
-       // Start from off (no field generated)\r
-    // Signal field is off with the appropriate LED\r
-    LED_D_OFF();\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);\r
-    SpinDelay(200);\r
-\r
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-    FpgaSetupSsc();\r
-\r
-       // Now give it time to spin up.\r
-    // Signal field is on with the appropriate LED\r
-    LED_D_ON();\r
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);\r
-       SpinDelay(200);\r
-\r
-       LED_A_ON();\r
-       LED_B_OFF();\r
-       LED_C_OFF();\r
-\r
-       int samples = 0;\r
-       int tsamples = 0;\r
-       int wait = 0;\r
-       int elapsed = 0;\r
-\r
-       while(1) {\r
-               // Send WUPA (or REQA)\r
-               TransmitFor14443a(req1, req1Len, &tsamples, &wait);\r
-\r
-    // Store reader command in buffer\r
-    if (!LogTrace(cmd1,1,0,GetParity(cmd1,1),TRUE)) break;\r
-    \r
-    // Test if the action was cancelled\r
-    if(BUTTON_PRESS()) {\r
-      break;\r
-    }\r
-    \r
-               if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-    \r
-    // Log the ATQA\r
-    if (!LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE)) break;\r
-\r
-    // Store reader command in buffer\r
-    if (!LogTrace(cmd2,2,0,GetParity(cmd2,2),TRUE)) break;\r
-    TransmitFor14443a(req2, req2Len, &samples, &wait);\r
-\r
-               if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-\r
-    // Log the uid\r
-    if (!LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE)) break;\r
-    \r
-               // Construct SELECT UID command\r
-               // First copy the 5 bytes (Mifare Classic) after the 93 70\r
-               memcpy(cmd3+2,receivedAnswer,5);\r
-               // Secondly compute the two CRC bytes at the end\r
-               ComputeCrc14443(CRC_14443_A, cmd3, 7, &cmd3[7], &cmd3[8]);\r
-\r
-               // Store reader command in buffer\r
-    if (!LogTrace(cmd3,9,0,GetParity(cmd5,9),TRUE)) break;\r
-               \r
-               CodeIso14443aAsReader(cmd3, sizeof(cmd3));\r
-               memcpy(req3, ToSend, ToSendMax); req3Len = ToSendMax;\r
-\r
-               // Select the card\r
-               TransmitFor14443a(req3, req3Len, &samples, &wait);\r
-               if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-\r
-    // Log the SAK\r
-    if (!LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE)) break;\r
-\r
-    // OK we have selected at least at cascade 1, lets see if first byte of UID was 0x88 in\r
-    // which case we need to make a cascade 2 request and select - this is a long UID\r
-               if (receivedAnswer[0] == 0x88)\r
-               {\r
-      // Do cascade level 2 stuff\r
-      ///////////////////////////////////////////////////////////////////\r
-      // First issue a '95 20' identify request\r
-      // Ask for card UID (part 2)\r
-      TransmitFor14443a(req4, req4Len, &tsamples, &wait);\r
-\r
-      // Store reader command in buffer\r
-      if (!LogTrace(cmd4,2,0,GetParity(cmd4,2),TRUE)) break;\r
-\r
-      if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-\r
-      //////////////////////////////////////////////////////////////////\r
-      // Then Construct SELECT UID (cascasde 2) command\r
-      DbpString("Just about to copy the UID out of the cascade 2 id req");\r
-      // First copy the 5 bytes (Mifare Classic) after the 95 70\r
-      memcpy(cmd5+2,receivedAnswer,5);\r
-      // Secondly compute the two CRC bytes at the end\r
-      ComputeCrc14443(CRC_14443_A, cmd4, 7, &cmd5[7], &cmd5[8]);\r
-\r
-      // Store reader command in buffer\r
-      if (!LogTrace(cmd5,9,0,GetParity(cmd5,9),TRUE)) break;\r
-\r
-      CodeIso14443aAsReader(cmd5, sizeof(cmd5));\r
-      memcpy(req5, ToSend, ToSendMax); req5Len = ToSendMax;\r
-      \r
-      // Select the card\r
-      TransmitFor14443a(req4, req4Len, &samples, &wait);\r
-      if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-      \r
-      // Log the SAK\r
-      if (!LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE)) break;\r
-               }\r
-\r
-               // Secondly compute the two CRC bytes at the end\r
-               ComputeCrc14443(CRC_14443_A, cmd7, 2, &cmd7[2], &cmd7[3]);\r
-               CodeIso14443aAsReader(cmd7, sizeof(cmd7));\r
-               memcpy(req7, ToSend, ToSendMax); req7Len = ToSendMax;\r
-\r
-               // Send authentication request (Mifare Classic)\r
-               TransmitFor14443a(req7, req7Len, &samples, &wait);\r
-    // Store reader command in buffer\r
-    if (!LogTrace(cmd7,4,0,GetParity(cmd7,4),TRUE)) break;\r
-\r
-               if(!GetIso14443aAnswerFromTag(receivedAnswer, 100, &samples, &elapsed)) continue;\r
-\r
-    // We received probably a random, continue and trace!\r
-    if (!LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE)) break;\r
-       }\r
-\r
-  // Thats it...\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);\r
-       LEDsoff();\r
-       DbpIntegers(rsamples, 0xCC, 0xCC);\r
-       DbpString("ready..");\r
-}\r
+//-----------------------------------------------------------------------------
+// Gerhard de Koning Gans - May 2008
+//
+// 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 14443 type A.
+//-----------------------------------------------------------------------------
+
+#include "proxmark3.h"
+#include "apps.h"
+#include "util.h"
+#include "string.h"
+
+#include "iso14443crc.h"
+
+static uint8_t *trace = (uint8_t *) BigBuf;
+static int traceLen = 0;
+static int rsamples = 0;
+static int tracing = TRUE;
+
+typedef enum {
+       SEC_D = 1,
+       SEC_E = 2,
+       SEC_F = 3,
+       SEC_X = 4,
+       SEC_Y = 5,
+       SEC_Z = 6
+} SecType;
+
+static const uint8_t OddByteParity[256] = {
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
+  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
+};
+
+// BIG CHANGE - UNDERSTAND THIS BEFORE WE COMMIT
+#define RECV_CMD_OFFSET   3032
+#define RECV_RES_OFFSET   3096
+#define DMA_BUFFER_OFFSET 3160
+#define DMA_BUFFER_SIZE   4096
+#define TRACE_LENGTH      3000
+
+//-----------------------------------------------------------------------------
+// Generate the parity value for a byte sequence
+//
+//-----------------------------------------------------------------------------
+uint32_t GetParity(const uint8_t * pbtCmd, int iLen)
+{
+  int i;
+  uint32_t dwPar = 0;
+
+  // Generate the encrypted data
+  for (i = 0; i < iLen; i++) {
+    // Save the encrypted parity bit
+    dwPar |= ((OddByteParity[pbtCmd[i]]) << i);
+  }
+  return dwPar;
+}
+
+static void AppendCrc14443a(uint8_t* data, int len)
+{
+  ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
+}
+
+int LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, int bReader)
+{
+  // Return when trace is full
+  if (traceLen >= TRACE_LENGTH) return FALSE;
+
+  // Trace the random, i'm curious
+  rsamples += iSamples;
+  trace[traceLen++] = ((rsamples >> 0) & 0xff);
+  trace[traceLen++] = ((rsamples >> 8) & 0xff);
+  trace[traceLen++] = ((rsamples >> 16) & 0xff);
+  trace[traceLen++] = ((rsamples >> 24) & 0xff);
+  if (!bReader) {
+    trace[traceLen - 1] |= 0x80;
+  }
+  trace[traceLen++] = ((dwParity >> 0) & 0xff);
+  trace[traceLen++] = ((dwParity >> 8) & 0xff);
+  trace[traceLen++] = ((dwParity >> 16) & 0xff);
+  trace[traceLen++] = ((dwParity >> 24) & 0xff);
+  trace[traceLen++] = iLen;
+  memcpy(trace + traceLen, btBytes, iLen);
+  traceLen += iLen;
+  return TRUE;
+}
+
+int LogTraceInfo(byte_t* data, size_t len)
+{
+  return LogTrace(data,len,0,GetParity(data,len),TRUE);
+}
+
+//-----------------------------------------------------------------------------
+// The software UART that receives commands from the reader, and its state
+// variables.
+//-----------------------------------------------------------------------------
+static struct {
+    enum {
+        STATE_UNSYNCD,
+        STATE_START_OF_COMMUNICATION,
+               STATE_MILLER_X,
+               STATE_MILLER_Y,
+               STATE_MILLER_Z,
+        STATE_ERROR_WAIT
+    }       state;
+    uint16_t    shiftReg;
+    int     bitCnt;
+    int     byteCnt;
+    int     byteCntMax;
+    int     posCnt;
+    int     syncBit;
+       int     parityBits;
+       int     samples;
+    int     highCnt;
+    int     bitBuffer;
+       enum {
+               DROP_NONE,
+               DROP_FIRST_HALF,
+               DROP_SECOND_HALF
+       }               drop;
+    uint8_t   *output;
+} Uart;
+
+static int MillerDecoding(int bit)
+{
+       int error = 0;
+       int bitright;
+
+       if(!Uart.bitBuffer) {
+               Uart.bitBuffer = bit ^ 0xFF0;
+               return FALSE;
+       }
+       else {
+               Uart.bitBuffer <<= 4;
+               Uart.bitBuffer ^= bit;
+       }
+
+       int EOC = FALSE;
+
+       if(Uart.state != STATE_UNSYNCD) {
+               Uart.posCnt++;
+
+               if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {
+                       bit = 0x00;
+               }
+               else {
+                       bit = 0x01;
+               }
+               if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {
+                       bitright = 0x00;
+               }
+               else {
+                       bitright = 0x01;
+               }
+               if(bit != bitright) { bit = bitright; }
+
+               if(Uart.posCnt == 1) {
+                       // measurement first half bitperiod
+                       if(!bit) {
+                               Uart.drop = DROP_FIRST_HALF;
+                       }
+               }
+               else {
+                       // measurement second half bitperiod
+                       if(!bit & (Uart.drop == DROP_NONE)) {
+                               Uart.drop = DROP_SECOND_HALF;
+                       }
+                       else if(!bit) {
+                               // measured a drop in first and second half
+                               // which should not be possible
+                               Uart.state = STATE_ERROR_WAIT;
+                               error = 0x01;
+                       }
+
+                       Uart.posCnt = 0;
+
+                       switch(Uart.state) {
+                               case STATE_START_OF_COMMUNICATION:
+                                       Uart.shiftReg = 0;
+                                       if(Uart.drop == DROP_SECOND_HALF) {
+                                               // error, should not happen in SOC
+                                               Uart.state = STATE_ERROR_WAIT;
+                                               error = 0x02;
+                                       }
+                                       else {
+                                               // correct SOC
+                                               Uart.state = STATE_MILLER_Z;
+                                       }
+                                       break;
+
+                               case STATE_MILLER_Z:
+                                       Uart.bitCnt++;
+                                       Uart.shiftReg >>= 1;
+                                       if(Uart.drop == DROP_NONE) {
+                                               // logic '0' followed by sequence Y
+                                               // end of communication
+                                               Uart.state = STATE_UNSYNCD;
+                                               EOC = TRUE;
+                                       }
+                                       // if(Uart.drop == DROP_FIRST_HALF) {
+                                       //      Uart.state = STATE_MILLER_Z; stay the same
+                                       //      we see a logic '0' }
+                                       if(Uart.drop == DROP_SECOND_HALF) {
+                                               // we see a logic '1'
+                                               Uart.shiftReg |= 0x100;
+                                               Uart.state = STATE_MILLER_X;
+                                       }
+                                       break;
+
+                               case STATE_MILLER_X:
+                                       Uart.shiftReg >>= 1;
+                                       if(Uart.drop == DROP_NONE) {
+                                               // sequence Y, we see a '0'
+                                               Uart.state = STATE_MILLER_Y;
+                                               Uart.bitCnt++;
+                                       }
+                                       if(Uart.drop == DROP_FIRST_HALF) {
+                                               // Would be STATE_MILLER_Z
+                                               // but Z does not follow X, so error
+                                               Uart.state = STATE_ERROR_WAIT;
+                                               error = 0x03;
+                                       }
+                                       if(Uart.drop == DROP_SECOND_HALF) {
+                                               // We see a '1' and stay in state X
+                                               Uart.shiftReg |= 0x100;
+                                               Uart.bitCnt++;
+                                       }
+                                       break;
+
+                               case STATE_MILLER_Y:
+                                       Uart.bitCnt++;
+                                       Uart.shiftReg >>= 1;
+                                       if(Uart.drop == DROP_NONE) {
+                                               // logic '0' followed by sequence Y
+                                               // end of communication
+                                               Uart.state = STATE_UNSYNCD;
+                                               EOC = TRUE;
+                                       }
+                                       if(Uart.drop == DROP_FIRST_HALF) {
+                                               // we see a '0'
+                                               Uart.state = STATE_MILLER_Z;
+                                       }
+                                       if(Uart.drop == DROP_SECOND_HALF) {
+                                               // We see a '1' and go to state X
+                                               Uart.shiftReg |= 0x100;
+                                               Uart.state = STATE_MILLER_X;
+                                       }
+                                       break;
+
+                               case STATE_ERROR_WAIT:
+                                       // That went wrong. Now wait for at least two bit periods
+                                       // and try to sync again
+                                       if(Uart.drop == DROP_NONE) {
+                                               Uart.highCnt = 6;
+                                               Uart.state = STATE_UNSYNCD;
+                                       }
+                                       break;
+
+                               default:
+                                       Uart.state = STATE_UNSYNCD;
+                                       Uart.highCnt = 0;
+                                       break;
+                       }
+
+                       Uart.drop = DROP_NONE;
+
+                       // should have received at least one whole byte...
+                       if((Uart.bitCnt == 2) && EOC && (Uart.byteCnt > 0)) {
+                               return TRUE;
+                       }
+
+                       if(Uart.bitCnt == 9) {
+                               Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
+                               Uart.byteCnt++;
+
+                               Uart.parityBits <<= 1;
+                               Uart.parityBits ^= ((Uart.shiftReg >> 8) & 0x01);
+
+                               if(EOC) {
+                                       // when End of Communication received and
+                                       // all data bits processed..
+                                       return TRUE;
+                               }
+                               Uart.bitCnt = 0;
+                       }
+
+                       /*if(error) {
+                               Uart.output[Uart.byteCnt] = 0xAA;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = error & 0xFF;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = 0xAA;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;
+                               Uart.byteCnt++;
+                               Uart.output[Uart.byteCnt] = 0xAA;
+                               Uart.byteCnt++;
+                               return TRUE;
+                       }*/
+               }
+
+       }
+       else {
+               bit = Uart.bitBuffer & 0xf0;
+               bit >>= 4;
+               bit ^= 0x0F;
+               if(bit) {
+                       // should have been high or at least (4 * 128) / fc
+                       // according to ISO this should be at least (9 * 128 + 20) / fc
+                       if(Uart.highCnt == 8) {
+                               // we went low, so this could be start of communication
+                               // it turns out to be safer to choose a less significant
+                               // syncbit... so we check whether the neighbour also represents the drop
+                               Uart.posCnt = 1;   // apparently we are busy with our first half bit period
+                               Uart.syncBit = bit & 8;
+                               Uart.samples = 3;
+                               if(!Uart.syncBit)       { Uart.syncBit = bit & 4; Uart.samples = 2; }
+                               else if(bit & 4)        { Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }
+                               if(!Uart.syncBit)       { Uart.syncBit = bit & 2; Uart.samples = 1; }
+                               else if(bit & 2)        { Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }
+                               if(!Uart.syncBit)       { Uart.syncBit = bit & 1; Uart.samples = 0;
+                                       if(Uart.syncBit & (Uart.bitBuffer & 8)) {
+                                               Uart.syncBit = 8;
+
+                                               // the first half bit period is expected in next sample
+                                               Uart.posCnt = 0;
+                                               Uart.samples = 3;
+                                       }
+                               }
+                               else if(bit & 1)        { Uart.syncBit = bit & 1; Uart.samples = 0; }
+
+                               Uart.syncBit <<= 4;
+                               Uart.state = STATE_START_OF_COMMUNICATION;
+                               Uart.drop = DROP_FIRST_HALF;
+                               Uart.bitCnt = 0;
+                               Uart.byteCnt = 0;
+                               Uart.parityBits = 0;
+                               error = 0;
+                       }
+                       else {
+                               Uart.highCnt = 0;
+                       }
+               }
+               else {
+                       if(Uart.highCnt < 8) {
+                               Uart.highCnt++;
+                       }
+               }
+       }
+
+    return FALSE;
+}
+
+//=============================================================================
+// ISO 14443 Type A - Manchester
+//=============================================================================
+
+static struct {
+    enum {
+        DEMOD_UNSYNCD,
+               DEMOD_START_OF_COMMUNICATION,
+               DEMOD_MANCHESTER_D,
+               DEMOD_MANCHESTER_E,
+               DEMOD_MANCHESTER_F,
+        DEMOD_ERROR_WAIT
+    }       state;
+    int     bitCount;
+    int     posCount;
+       int     syncBit;
+       int     parityBits;
+    uint16_t    shiftReg;
+       int     buffer;
+       int     buff;
+       int     samples;
+    int     len;
+       enum {
+               SUB_NONE,
+               SUB_FIRST_HALF,
+               SUB_SECOND_HALF
+       }               sub;
+    uint8_t   *output;
+} Demod;
+
+static int ManchesterDecoding(int v)
+{
+       int bit;
+       int modulation;
+       int error = 0;
+
+       if(!Demod.buff) {
+               Demod.buff = 1;
+               Demod.buffer = v;
+               return FALSE;
+       }
+       else {
+               bit = Demod.buffer;
+               Demod.buffer = v;
+       }
+
+       if(Demod.state==DEMOD_UNSYNCD) {
+               Demod.output[Demod.len] = 0xfa;
+               Demod.syncBit = 0;
+               //Demod.samples = 0;
+               Demod.posCount = 1;             // This is the first half bit period, so after syncing handle the second part
+               if(bit & 0x08) { Demod.syncBit = 0x08; }
+               if(!Demod.syncBit)      {
+                       if(bit & 0x04) { Demod.syncBit = 0x04; }
+               }
+               else if(bit & 0x04) { Demod.syncBit = 0x04; bit <<= 4; }
+               if(!Demod.syncBit)      {
+                       if(bit & 0x02) { Demod.syncBit = 0x02; }
+               }
+               else if(bit & 0x02) { Demod.syncBit = 0x02; bit <<= 4; }
+               if(!Demod.syncBit)      {
+                       if(bit & 0x01) { Demod.syncBit = 0x01; }
+
+                       if(Demod.syncBit & (Demod.buffer & 0x08)) {
+                               Demod.syncBit = 0x08;
+
+                               // The first half bitperiod is expected in next sample
+                               Demod.posCount = 0;
+                               Demod.output[Demod.len] = 0xfb;
+                       }
+               }
+               else if(bit & 0x01) { Demod.syncBit = 0x01; }
+
+               if(Demod.syncBit) {
+                       Demod.len = 0;
+                       Demod.state = DEMOD_START_OF_COMMUNICATION;
+                       Demod.sub = SUB_FIRST_HALF;
+                       Demod.bitCount = 0;
+                       Demod.shiftReg = 0;
+                       Demod.parityBits = 0;
+                       Demod.samples = 0;
+                       if(Demod.posCount) {
+                               switch(Demod.syncBit) {
+                                       case 0x08: Demod.samples = 3; break;
+                                       case 0x04: Demod.samples = 2; break;
+                                       case 0x02: Demod.samples = 1; break;
+                                       case 0x01: Demod.samples = 0; break;
+                               }
+                       }
+                       error = 0;
+               }
+       }
+       else {
+               //modulation = bit & Demod.syncBit;
+               modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
+
+               Demod.samples += 4;
+
+               if(Demod.posCount==0) {
+                       Demod.posCount = 1;
+                       if(modulation) {
+                               Demod.sub = SUB_FIRST_HALF;
+                       }
+                       else {
+                               Demod.sub = SUB_NONE;
+                       }
+               }
+               else {
+                       Demod.posCount = 0;
+                       if(modulation && (Demod.sub == SUB_FIRST_HALF)) {
+                               if(Demod.state!=DEMOD_ERROR_WAIT) {
+                                       Demod.state = DEMOD_ERROR_WAIT;
+                                       Demod.output[Demod.len] = 0xaa;
+                                       error = 0x01;
+                               }
+                       }
+                       else if(modulation) {
+                               Demod.sub = SUB_SECOND_HALF;
+                       }
+
+                       switch(Demod.state) {
+                               case DEMOD_START_OF_COMMUNICATION:
+                                       if(Demod.sub == SUB_FIRST_HALF) {
+                                               Demod.state = DEMOD_MANCHESTER_D;
+                                       }
+                                       else {
+                                               Demod.output[Demod.len] = 0xab;
+                                               Demod.state = DEMOD_ERROR_WAIT;
+                                               error = 0x02;
+                                       }
+                                       break;
+
+                               case DEMOD_MANCHESTER_D:
+                               case DEMOD_MANCHESTER_E:
+                                       if(Demod.sub == SUB_FIRST_HALF) {
+                                               Demod.bitCount++;
+                                               Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;
+                                               Demod.state = DEMOD_MANCHESTER_D;
+                                       }
+                                       else if(Demod.sub == SUB_SECOND_HALF) {
+                                               Demod.bitCount++;
+                                               Demod.shiftReg >>= 1;
+                                               Demod.state = DEMOD_MANCHESTER_E;
+                                       }
+                                       else {
+                                               Demod.state = DEMOD_MANCHESTER_F;
+                                       }
+                                       break;
+
+                               case DEMOD_MANCHESTER_F:
+                                       // Tag response does not need to be a complete byte!
+                                       if(Demod.len > 0 || Demod.bitCount > 0) {
+                                               if(Demod.bitCount > 0) {
+                                                       Demod.shiftReg >>= (9 - Demod.bitCount);
+                                                       Demod.output[Demod.len] = Demod.shiftReg & 0xff;
+                                                       Demod.len++;
+                                                       // No parity bit, so just shift a 0
+                                                       Demod.parityBits <<= 1;
+                                               }
+
+                                               Demod.state = DEMOD_UNSYNCD;
+                                               return TRUE;
+                                       }
+                                       else {
+                                               Demod.output[Demod.len] = 0xad;
+                                               Demod.state = DEMOD_ERROR_WAIT;
+                                               error = 0x03;
+                                       }
+                                       break;
+
+                               case DEMOD_ERROR_WAIT:
+                                       Demod.state = DEMOD_UNSYNCD;
+                                       break;
+
+                               default:
+                                       Demod.output[Demod.len] = 0xdd;
+                                       Demod.state = DEMOD_UNSYNCD;
+                                       break;
+                       }
+
+                       if(Demod.bitCount>=9) {
+                               Demod.output[Demod.len] = Demod.shiftReg & 0xff;
+                               Demod.len++;
+
+                               Demod.parityBits <<= 1;
+                               Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);
+
+                               Demod.bitCount = 0;
+                               Demod.shiftReg = 0;
+                       }
+
+                       /*if(error) {
+                               Demod.output[Demod.len] = 0xBB;
+                               Demod.len++;
+                               Demod.output[Demod.len] = error & 0xFF;
+                               Demod.len++;
+                               Demod.output[Demod.len] = 0xBB;
+                               Demod.len++;
+                               Demod.output[Demod.len] = bit & 0xFF;
+                               Demod.len++;
+                               Demod.output[Demod.len] = Demod.buffer & 0xFF;
+                               Demod.len++;
+                               Demod.output[Demod.len] = Demod.syncBit & 0xFF;
+                               Demod.len++;
+                               Demod.output[Demod.len] = 0xBB;
+                               Demod.len++;
+                               return TRUE;
+                       }*/
+
+               }
+
+       } // end (state != UNSYNCED)
+
+    return FALSE;
+}
+
+//=============================================================================
+// Finally, a `sniffer' for ISO 14443 Type A
+// Both sides of communication!
+//=============================================================================
+
+//-----------------------------------------------------------------------------
+// Record the sequence of commands sent by the reader to the tag, with
+// triggering so that we start recording at the point that the tag is moved
+// near the reader.
+//-----------------------------------------------------------------------------
+void SnoopIso14443a(void)
+{
+//     #define RECV_CMD_OFFSET         2032    // original (working as of 21/2/09) values
+//     #define RECV_RES_OFFSET         2096    // original (working as of 21/2/09) values
+//     #define DMA_BUFFER_OFFSET       2160    // original (working as of 21/2/09) values
+//     #define DMA_BUFFER_SIZE         4096    // original (working as of 21/2/09) values
+//     #define TRACE_LENGTH            2000    // original (working as of 21/2/09) values
+
+    // 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; // FALSE to wait first for card
+
+    // The command (reader -> tag) that we're receiving.
+       // The length of a received command will in most cases be no more than 18 bytes.
+       // So 32 should be enough!
+    uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
+    // The response (tag -> reader) that we're receiving.
+    uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
+
+    // As we receive stuff, we copy it from receivedCmd or receivedResponse
+    // into trace, along with its length and other annotations.
+    //uint8_t *trace = (uint8_t *)BigBuf;
+    //int traceLen = 0;
+
+    // The DMA buffer, used to stream samples from the FPGA
+    int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
+    int lastRxCounter;
+    int8_t *upTo;
+    int smpl;
+    int maxBehindBy = 0;
+
+    // Count of samples received so far, so that we can include timing
+    // information in the trace buffer.
+    int samples = 0;
+       int rsamples = 0;
+
+    memset(trace, 0x44, RECV_CMD_OFFSET);
+
+    // Set up the demodulator for tag -> reader responses.
+    Demod.output = receivedResponse;
+    Demod.len = 0;
+    Demod.state = DEMOD_UNSYNCD;
+
+    // And the reader -> tag commands
+    memset(&Uart, 0, sizeof(Uart));
+    Uart.output = receivedCmd;
+    Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
+    Uart.state = STATE_UNSYNCD;
+
+    // And put the FPGA in the appropriate mode
+    // Signal field is off with the appropriate LED
+    LED_D_OFF();
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
+    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+       // Setup for the DMA.
+    FpgaSetupSsc();
+    upTo = dmaBuf;
+    lastRxCounter = DMA_BUFFER_SIZE;
+    FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
+
+    LED_A_ON();
+
+    // And now we loop, receiving samples.
+    for(;;) {
+               WDT_HIT();
+        int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
+                                (DMA_BUFFER_SIZE-1);
+        if(behindBy > maxBehindBy) {
+            maxBehindBy = behindBy;
+            if(behindBy > 400) {
+                DbpString("blew circular buffer!");
+                goto done;
+            }
+        }
+        if(behindBy < 1) continue;
+
+        smpl = upTo[0];
+        upTo++;
+        lastRxCounter -= 1;
+        if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
+            upTo -= DMA_BUFFER_SIZE;
+            lastRxCounter += DMA_BUFFER_SIZE;
+            AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
+            AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+        }
+
+        samples += 4;
+#define HANDLE_BIT_IF_BODY \
+            LED_C_ON(); \
+                       if(triggered) { \
+                               trace[traceLen++] = ((rsamples >>  0) & 0xff); \
+                trace[traceLen++] = ((rsamples >>  8) & 0xff); \
+                trace[traceLen++] = ((rsamples >> 16) & 0xff); \
+                trace[traceLen++] = ((rsamples >> 24) & 0xff); \
+                               trace[traceLen++] = ((Uart.parityBits >>  0) & 0xff); \
+                               trace[traceLen++] = ((Uart.parityBits >>  8) & 0xff); \
+                               trace[traceLen++] = ((Uart.parityBits >> 16) & 0xff); \
+                               trace[traceLen++] = ((Uart.parityBits >> 24) & 0xff); \
+                trace[traceLen++] = Uart.byteCnt; \
+                memcpy(trace+traceLen, receivedCmd, Uart.byteCnt); \
+                traceLen += Uart.byteCnt; \
+                if(traceLen > TRACE_LENGTH) break; \
+            } \
+            /* And ready to receive another command. */ \
+            Uart.state = STATE_UNSYNCD; \
+            /* And also reset the demod code, which might have been */ \
+            /* false-triggered by the commands from the reader. */ \
+            Demod.state = DEMOD_UNSYNCD; \
+                       LED_B_OFF(); \
+
+               if(MillerDecoding((smpl & 0xF0) >> 4)) {
+            rsamples = samples - Uart.samples;
+                       HANDLE_BIT_IF_BODY
+        }
+               if(ManchesterDecoding(smpl & 0x0F)) {
+                       rsamples = samples - Demod.samples;
+                       LED_B_ON();
+
+                       // timestamp, as a count of samples
+                       trace[traceLen++] = ((rsamples >>  0) & 0xff);
+                       trace[traceLen++] = ((rsamples >>  8) & 0xff);
+                       trace[traceLen++] = ((rsamples >> 16) & 0xff);
+                       trace[traceLen++] = 0x80 | ((rsamples >> 24) & 0xff);
+                       trace[traceLen++] = ((Demod.parityBits >>  0) & 0xff);
+                       trace[traceLen++] = ((Demod.parityBits >>  8) & 0xff);
+                       trace[traceLen++] = ((Demod.parityBits >> 16) & 0xff);
+                       trace[traceLen++] = ((Demod.parityBits >> 24) & 0xff);
+                       // length
+                       trace[traceLen++] = Demod.len;
+                       memcpy(trace+traceLen, receivedResponse, Demod.len);
+                       traceLen += Demod.len;
+                       if(traceLen > TRACE_LENGTH) break;
+
+               triggered = TRUE;
+
+            // And ready to receive another response.
+            memset(&Demod, 0, sizeof(Demod));
+            Demod.output = receivedResponse;
+            Demod.state = DEMOD_UNSYNCD;
+                       LED_C_OFF();
+               }
+
+        if(BUTTON_PRESS()) {
+            DbpString("cancelled_a");
+            goto done;
+        }
+    }
+
+    DbpString("COMMAND FINISHED");
+
+    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
+    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
+
+done:
+    AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
+    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
+    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
+    LED_A_OFF();
+    LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+}
+
+// Prepare communication bits to send to FPGA
+void Sequence(SecType seq)
+{
+       ToSendMax++;
+       switch(seq) {
+       // CARD TO READER
+       case SEC_D:
+               // Sequence D: 11110000
+               // modulation with subcarrier during first half
+        ToSend[ToSendMax] = 0xf0;
+               break;
+       case SEC_E:
+               // Sequence E: 00001111
+               // modulation with subcarrier during second half
+        ToSend[ToSendMax] = 0x0f;
+               break;
+       case SEC_F:
+               // Sequence F: 00000000
+               // no modulation with subcarrier
+        ToSend[ToSendMax] = 0x00;
+               break;
+       // READER TO CARD
+       case SEC_X:
+               // Sequence X: 00001100
+               // drop after half a period
+        ToSend[ToSendMax] = 0x0c;
+               break;
+       case SEC_Y:
+       default:
+               // Sequence Y: 00000000
+               // no drop
+        ToSend[ToSendMax] = 0x00;
+               break;
+       case SEC_Z:
+               // Sequence Z: 11000000
+               // drop at start
+        ToSend[ToSendMax] = 0xc0;
+               break;
+       }
+}
+
+//-----------------------------------------------------------------------------
+// Prepare tag messages
+//-----------------------------------------------------------------------------
+static void CodeIso14443aAsTag(const uint8_t *cmd, int len)
+{
+    int i;
+       int oddparity;
+
+    ToSendReset();
+
+       // Correction bit, might be removed when not needed
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);  // 1
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+
+       // Send startbit
+       Sequence(SEC_D);
+
+    for(i = 0; i < len; i++) {
+        int j;
+        uint8_t b = cmd[i];
+
+               // Data bits
+        oddparity = 0x01;
+               for(j = 0; j < 8; j++) {
+            oddparity ^= (b & 1);
+                       if(b & 1) {
+                               Sequence(SEC_D);
+                       } else {
+                               Sequence(SEC_E);
+            }
+            b >>= 1;
+        }
+
+        // Parity bit
+        if(oddparity) {
+                       Sequence(SEC_D);
+               } else {
+                       Sequence(SEC_E);
+               }
+    }
+
+    // Send stopbit
+       Sequence(SEC_F);
+
+       // Flush the buffer in FPGA!!
+       for(i = 0; i < 5; i++) {
+               Sequence(SEC_F);
+       }
+
+    // Convert from last byte pos to length
+    ToSendMax++;
+
+    // Add a few more for slop
+    ToSend[ToSendMax++] = 0x00;
+       ToSend[ToSendMax++] = 0x00;
+    //ToSendMax += 2;
+}
+
+//-----------------------------------------------------------------------------
+// This is to send a NACK kind of answer, its only 3 bits, I know it should be 4
+//-----------------------------------------------------------------------------
+static void CodeStrangeAnswer()
+{
+       int i;
+
+    ToSendReset();
+
+       // Correction bit, might be removed when not needed
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);  // 1
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+       ToSendStuffBit(0);
+
+       // Send startbit
+       Sequence(SEC_D);
+
+       // 0
+       Sequence(SEC_E);
+
+       // 0
+       Sequence(SEC_E);
+
+       // 1
+       Sequence(SEC_D);
+
+    // Send stopbit
+       Sequence(SEC_F);
+
+       // Flush the buffer in FPGA!!
+       for(i = 0; i < 5; i++) {
+               Sequence(SEC_F);
+       }
+
+    // Convert from last byte pos to length
+    ToSendMax++;
+
+    // Add a few more for slop
+    ToSend[ToSendMax++] = 0x00;
+       ToSend[ToSendMax++] = 0x00;
+    //ToSendMax += 2;
+}
+
+//-----------------------------------------------------------------------------
+// Wait for commands from reader
+// Stop when button is pressed
+// Or return TRUE when command is captured
+//-----------------------------------------------------------------------------
+static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen)
+{
+    // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
+    // only, since we are receiving, not transmitting).
+    // Signal field is off with the appropriate LED
+    LED_D_OFF();
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+    // Now run a `software UART' on the stream of incoming samples.
+    Uart.output = received;
+    Uart.byteCntMax = maxLen;
+    Uart.state = STATE_UNSYNCD;
+
+    for(;;) {
+        WDT_HIT();
+
+        if(BUTTON_PRESS()) return FALSE;
+
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+            AT91C_BASE_SSC->SSC_THR = 0x00;
+        }
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+            uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+                       if(MillerDecoding((b & 0xf0) >> 4)) {
+                               *len = Uart.byteCnt;
+                               return TRUE;
+                       }
+                       if(MillerDecoding(b & 0x0f)) {
+                               *len = Uart.byteCnt;
+                               return TRUE;
+                       }
+        }
+    }
+}
+
+//-----------------------------------------------------------------------------
+// Main loop of simulated tag: receive commands from reader, decide what
+// response to send, and send it.
+//-----------------------------------------------------------------------------
+void SimulateIso14443aTag(int tagType, int TagUid)
+{
+       // This function contains the tag emulation
+
+       // Prepare protocol messages
+    // static const uint8_t cmd1[] = { 0x26 };
+//     static const uint8_t response1[] = { 0x02, 0x00 }; // Says: I am Mifare 4k - original line - greg
+//
+       static const uint8_t response1[] = { 0x44, 0x03 }; // Says: I am a DESFire Tag, ph33r me
+//     static const uint8_t response1[] = { 0x44, 0x00 }; // Says: I am a ULTRALITE Tag, 0wn me
+
+       // UID response
+    // static const uint8_t cmd2[] = { 0x93, 0x20 };
+    //static const uint8_t response2[] = { 0x9a, 0xe5, 0xe4, 0x43, 0xd8 }; // original value - greg
+
+
+
+// my desfire
+    static const uint8_t response2[] = { 0x88, 0x04, 0x21, 0x3f, 0x4d }; // known uid - note cascade (0x88), 2nd byte (0x04) = NXP/Phillips
+
+
+// When reader selects us during cascade1 it will send cmd3
+//uint8_t response3[] = { 0x04, 0x00, 0x00 }; // SAK Select (cascade1) successful response (ULTRALITE)
+uint8_t response3[] = { 0x24, 0x00, 0x00 }; // SAK Select (cascade1) successful response (DESFire)
+ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
+
+// send cascade2 2nd half of UID
+static const uint8_t response2a[] = { 0x51, 0x48, 0x1d, 0x80, 0x84 }; //  uid - cascade2 - 2nd half (4 bytes) of UID+ BCCheck
+// NOTE : THE CRC on the above may be wrong as I have obfuscated the actual UID
+
+
+// When reader selects us during cascade2 it will send cmd3a
+//uint8_t response3a[] = { 0x00, 0x00, 0x00 }; // SAK Select (cascade2) successful response (ULTRALITE)
+uint8_t response3a[] = { 0x20, 0x00, 0x00 }; // SAK Select (cascade2) successful response (DESFire)
+ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
+
+    static const uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
+
+    uint8_t *resp;
+    int respLen;
+
+    // Longest possible response will be 16 bytes + 2 CRC = 18 bytes
+       // This will need
+       //    144        data bits (18 * 8)
+       //     18        parity bits
+       //      2        Start and stop
+       //      1        Correction bit (Answer in 1172 or 1236 periods, see FPGA)
+       //      1        just for the case
+       // ----------- +
+       //    166
+       //
+       // 166 bytes, since every bit that needs to be send costs us a byte
+       //
+
+
+    // Respond with card type
+    uint8_t *resp1 = (((uint8_t *)BigBuf) + 800);
+    int resp1Len;
+
+    // Anticollision cascade1 - respond with uid
+    uint8_t *resp2 = (((uint8_t *)BigBuf) + 970);
+    int resp2Len;
+
+    // Anticollision cascade2 - respond with 2nd half of uid if asked
+    // we're only going to be asked if we set the 1st byte of the UID (during cascade1) to 0x88
+    uint8_t *resp2a = (((uint8_t *)BigBuf) + 1140);
+    int resp2aLen;
+
+    // Acknowledge select - cascade 1
+    uint8_t *resp3 = (((uint8_t *)BigBuf) + 1310);
+    int resp3Len;
+
+    // Acknowledge select - cascade 2
+    uint8_t *resp3a = (((uint8_t *)BigBuf) + 1480);
+    int resp3aLen;
+
+    // Response to a read request - not implemented atm
+    uint8_t *resp4 = (((uint8_t *)BigBuf) + 1550);
+    int resp4Len;
+
+    // Authenticate response - nonce
+    uint8_t *resp5 = (((uint8_t *)BigBuf) + 1720);
+    int resp5Len;
+
+    uint8_t *receivedCmd = (uint8_t *)BigBuf;
+    int len;
+
+    int i;
+       int u;
+       uint8_t b;
+
+       // To control where we are in the protocol
+       int order = 0;
+       int lastorder;
+
+       // Just to allow some checks
+       int happened = 0;
+       int happened2 = 0;
+
+    int cmdsRecvd = 0;
+
+       int fdt_indicator;
+
+    memset(receivedCmd, 0x44, 400);
+
+       // Prepare the responses of the anticollision phase
+       // there will be not enough time to do this at the moment the reader sends it REQA
+
+       // Answer to request
+       CodeIso14443aAsTag(response1, sizeof(response1));
+    memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
+
+       // Send our UID (cascade 1)
+       CodeIso14443aAsTag(response2, sizeof(response2));
+    memcpy(resp2, ToSend, ToSendMax); resp2Len = ToSendMax;
+
+       // Answer to select (cascade1)
+       CodeIso14443aAsTag(response3, sizeof(response3));
+    memcpy(resp3, ToSend, ToSendMax); resp3Len = ToSendMax;
+
+       // Send the cascade 2 2nd part of the uid
+       CodeIso14443aAsTag(response2a, sizeof(response2a));
+    memcpy(resp2a, ToSend, ToSendMax); resp2aLen = ToSendMax;
+
+       // Answer to select (cascade 2)
+       CodeIso14443aAsTag(response3a, sizeof(response3a));
+    memcpy(resp3a, ToSend, ToSendMax); resp3aLen = ToSendMax;
+
+       // Strange answer is an example of rare message size (3 bits)
+       CodeStrangeAnswer();
+       memcpy(resp4, ToSend, ToSendMax); resp4Len = ToSendMax;
+
+       // Authentication answer (random nonce)
+       CodeIso14443aAsTag(response5, sizeof(response5));
+    memcpy(resp5, ToSend, ToSendMax); resp5Len = ToSendMax;
+
+    // We need to listen to the high-frequency, peak-detected path.
+    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+    FpgaSetupSsc();
+
+    cmdsRecvd = 0;
+
+    LED_A_ON();
+       for(;;) {
+
+               if(!GetIso14443aCommandFromReader(receivedCmd, &len, 100)) {
+            DbpString("button press");
+            break;
+        }
+       // doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated
+        // Okay, look at the command now.
+        lastorder = order;
+               i = 1; // first byte transmitted
+        if(receivedCmd[0] == 0x26) {
+                       // Received a REQUEST
+                       resp = resp1; respLen = resp1Len; order = 1;
+                       //DbpString("Hello request from reader:");
+               } else if(receivedCmd[0] == 0x52) {
+                       // Received a WAKEUP
+                       resp = resp1; respLen = resp1Len; order = 6;
+//                     //DbpString("Wakeup request from reader:");
+
+               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) {   // greg - cascade 1 anti-collision
+                       // Received request for UID (cascade 1)
+                       resp = resp2; respLen = resp2Len; order = 2;
+//                     DbpString("UID (cascade 1) request from reader:");
+//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+
+               } else if(receivedCmd[1] == 0x20 && receivedCmd[0] ==0x95) {    // greg - cascade 2 anti-collision
+                       // Received request for UID (cascade 2)
+                       resp = resp2a; respLen = resp2aLen; order = 20;
+//                     DbpString("UID (cascade 2) request from reader:");
+//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+
+               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x93) {    // greg - cascade 1 select
+                       // Received a SELECT
+                       resp = resp3; respLen = resp3Len; order = 3;
+//                     DbpString("Select (cascade 1) request from reader:");
+//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+
+               } else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x95) {    // greg - cascade 2 select
+                       // Received a SELECT
+                       resp = resp3a; respLen = resp3aLen; order = 30;
+//                     DbpString("Select (cascade 2) request from reader:");
+//                     DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+
+               } else if(receivedCmd[0] == 0x30) {
+                       // Received a READ
+                       resp = resp4; respLen = resp4Len; order = 4; // Do nothing
+                       Dbprintf("Read request from reader: %x %x %x",
+                               receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+
+               } else if(receivedCmd[0] == 0x50) {
+                       // Received a HALT
+                       resp = resp1; respLen = 0; order = 5; // Do nothing
+                       DbpString("Reader requested we HALT!:");
+
+               } else if(receivedCmd[0] == 0x60) {
+                       // Received an authentication request
+                       resp = resp5; respLen = resp5Len; order = 7;
+                       Dbprintf("Authenticate request from reader: %x %x %x",
+                               receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+
+               } else if(receivedCmd[0] == 0xE0) {
+                       // Received a RATS request
+                       resp = resp1; respLen = 0;order = 70;
+                       Dbprintf("RATS request from reader: %x %x %x",
+                               receivedCmd[0], receivedCmd[1], receivedCmd[2]);
+        } else {
+            // Never seen this command before
+               Dbprintf("Unknown command received from reader: %x %x %x %x %x %x %x %x %x",
+                       receivedCmd[0], receivedCmd[1], receivedCmd[2],
+                       receivedCmd[3], receivedCmd[3], receivedCmd[4],
+                       receivedCmd[5], receivedCmd[6], receivedCmd[7]);
+                       // Do not respond
+                       resp = resp1; respLen = 0; order = 0;
+        }
+
+               // Count number of wakeups received after a halt
+               if(order == 6 && lastorder == 5) { happened++; }
+
+               // Count number of other messages after a halt
+               if(order != 6 && lastorder == 5) { happened2++; }
+
+               // Look at last parity bit to determine timing of answer
+               if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) {
+                       // 1236, so correction bit needed
+                       i = 0;
+               }
+
+        memset(receivedCmd, 0x44, 32);
+
+               if(cmdsRecvd > 999) {
+                       DbpString("1000 commands later...");
+            break;
+        }
+               else {
+                       cmdsRecvd++;
+               }
+
+        if(respLen <= 0) continue;
+
+        // Modulate Manchester
+               FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
+        AT91C_BASE_SSC->SSC_THR = 0x00;
+        FpgaSetupSsc();
+
+               // ### Transmit the response ###
+               u = 0;
+               b = 0x00;
+               fdt_indicator = FALSE;
+        for(;;) {
+            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                               volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+                (void)b;
+            }
+            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                               if(i > respLen) {
+                                       b = 0x00;
+                                       u++;
+                               } else {
+                                       b = resp[i];
+                                       i++;
+                               }
+                               AT91C_BASE_SSC->SSC_THR = b;
+
+                if(u > 4) {
+                    break;
+                }
+            }
+                       if(BUTTON_PRESS()) {
+                           break;
+                       }
+        }
+
+    }
+
+       Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
+       LED_A_OFF();
+}
+
+//-----------------------------------------------------------------------------
+// Transmit the command (to the tag) that was placed in ToSend[].
+//-----------------------------------------------------------------------------
+static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait)
+{
+  int c;
+
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+
+       if (wait)
+    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 uint32_t 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 uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+      (void)r;
+    }
+    WDT_HIT();
+  }
+       if (samples) *samples = (c + *wait) << 3;
+}
+
+//-----------------------------------------------------------------------------
+// To generate an arbitrary stream from reader
+//
+//-----------------------------------------------------------------------------
+void ArbitraryFromReader(const uint8_t *cmd, int parity, int len)
+{
+       int i;
+       int j;
+       int last;
+    uint8_t b;
+
+       ToSendReset();
+
+       // Start of Communication (Seq. Z)
+       Sequence(SEC_Z);
+       last = 0;
+
+       for(i = 0; i < len; i++) {
+        // Data bits
+        b = cmd[i];
+               for(j = 0; j < 8; j++) {
+                       if(b & 1) {
+                               // Sequence X
+                               Sequence(SEC_X);
+                               last = 1;
+                       } else {
+                               if(last == 0) {
+                                       // Sequence Z
+                                       Sequence(SEC_Z);
+                               }
+                               else {
+                                       // Sequence Y
+                                       Sequence(SEC_Y);
+                                       last = 0;
+                               }
+                       }
+                       b >>= 1;
+
+               }
+
+               // Predefined parity bit, the flipper flips when needed, because of flips in byte sent
+               if(((parity >> (len - i - 1)) & 1)) {
+                       // Sequence X
+                       Sequence(SEC_X);
+                       last = 1;
+               } else {
+                       if(last == 0) {
+                               // Sequence Z
+                               Sequence(SEC_Z);
+                       }
+                       else {
+                               // Sequence Y
+                               Sequence(SEC_Y);
+                               last = 0;
+                       }
+               }
+       }
+
+       // End of Communication
+       if(last == 0) {
+               // Sequence Z
+               Sequence(SEC_Z);
+       }
+       else {
+               // Sequence Y
+               Sequence(SEC_Y);
+               last = 0;
+       }
+       // Sequence Y
+       Sequence(SEC_Y);
+
+       // Just to be sure!
+       Sequence(SEC_Y);
+       Sequence(SEC_Y);
+       Sequence(SEC_Y);
+
+    // Convert from last character reference to length
+    ToSendMax++;
+}
+
+//-----------------------------------------------------------------------------
+// Code a 7-bit command without parity bit
+// This is especially for 0x26 and 0x52 (REQA and WUPA)
+//-----------------------------------------------------------------------------
+void ShortFrameFromReader(const uint8_t bt)
+{
+       int j;
+       int last;
+  uint8_t b;
+
+       ToSendReset();
+
+       // Start of Communication (Seq. Z)
+       Sequence(SEC_Z);
+       last = 0;
+
+       b = bt;
+       for(j = 0; j < 7; j++) {
+               if(b & 1) {
+                       // Sequence X
+                       Sequence(SEC_X);
+                       last = 1;
+               } else {
+                       if(last == 0) {
+                               // Sequence Z
+                               Sequence(SEC_Z);
+                       }
+                       else {
+                               // Sequence Y
+                               Sequence(SEC_Y);
+                               last = 0;
+                       }
+               }
+               b >>= 1;
+       }
+
+       // End of Communication
+       if(last == 0) {
+               // Sequence Z
+               Sequence(SEC_Z);
+       }
+       else {
+               // Sequence Y
+               Sequence(SEC_Y);
+               last = 0;
+       }
+       // Sequence Y
+       Sequence(SEC_Y);
+
+       // Just to be sure!
+       Sequence(SEC_Y);
+       Sequence(SEC_Y);
+       Sequence(SEC_Y);
+
+    // Convert from last character reference to length
+    ToSendMax++;
+}
+
+//-----------------------------------------------------------------------------
+// Prepare reader command to send to FPGA
+//
+//-----------------------------------------------------------------------------
+void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
+{
+  int i, j;
+  int last;
+  uint8_t b;
+
+  ToSendReset();
+
+  // Start of Communication (Seq. Z)
+  Sequence(SEC_Z);
+  last = 0;
+
+  // Generate send structure for the data bits
+  for (i = 0; i < len; i++) {
+    // Get the current byte to send
+    b = cmd[i];
+
+    for (j = 0; j < 8; j++) {
+      if (b & 1) {
+        // Sequence X
+        Sequence(SEC_X);
+        last = 1;
+      } else {
+        if (last == 0) {
+          // Sequence Z
+          Sequence(SEC_Z);
+        } else {
+          // Sequence Y
+          Sequence(SEC_Y);
+          last = 0;
+        }
+      }
+      b >>= 1;
+    }
+
+    // Get the parity bit
+    if ((dwParity >> i) & 0x01) {
+      // Sequence X
+      Sequence(SEC_X);
+      last = 1;
+    } else {
+      if (last == 0) {
+        // Sequence Z
+        Sequence(SEC_Z);
+      } else {
+        // Sequence Y
+        Sequence(SEC_Y);
+        last = 0;
+      }
+    }
+  }
+
+  // End of Communication
+  if (last == 0) {
+    // Sequence Z
+    Sequence(SEC_Z);
+  } else {
+    // Sequence Y
+    Sequence(SEC_Y);
+    last = 0;
+  }
+  // Sequence Y
+  Sequence(SEC_Y);
+
+  // Just to be sure!
+  Sequence(SEC_Y);
+  Sequence(SEC_Y);
+  Sequence(SEC_Y);
+
+  // Convert from last character reference to length
+  ToSendMax++;
+}
+
+//-----------------------------------------------------------------------------
+// Wait a certain time for tag response
+//  If a response is captured return TRUE
+//  If it takes to long return FALSE
+//-----------------------------------------------------------------------------
+static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
+{
+       // buffer needs to be 512 bytes
+       int c;
+
+       // Set FPGA mode to "reader listen mode", no modulation (listen
+    // only, since we are receiving, not transmitting).
+    // Signal field is on with the appropriate LED
+    LED_D_ON();
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
+
+    // Now get the answer from the card
+    Demod.output = receivedResponse;
+    Demod.len = 0;
+    Demod.state = DEMOD_UNSYNCD;
+
+       uint8_t b;
+       if (elapsed) *elapsed = 0;
+
+       c = 0;
+       for(;;) {
+        WDT_HIT();
+
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+            AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!
+                       if (elapsed) (*elapsed)++;
+        }
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       if(c < 512) { c++; } else { return FALSE; }
+            b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+                       if(ManchesterDecoding((b & 0xf0) >> 4)) {
+                               *samples = ((c - 1) << 3) + 4;
+                               return TRUE;
+                       }
+                       if(ManchesterDecoding(b & 0x0f)) {
+                               *samples = c << 3;
+                               return TRUE;
+                       }
+        }
+    }
+}
+
+void ReaderTransmitShort(const uint8_t* bt)
+{
+  int wait = 0;
+  int samples = 0;
+
+  ShortFrameFromReader(*bt);
+
+  // Select the card
+  TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
+
+  // Store reader command in buffer
+  if (tracing) LogTrace(bt,1,0,GetParity(bt,1),TRUE);
+}
+
+void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
+{
+  int wait = 0;
+  int samples = 0;
+
+  // This is tied to other size changes
+  //   uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024;
+  CodeIso14443aAsReaderPar(frame,len,par);
+
+  // Select the card
+  TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
+
+  // Store reader command in buffer
+  if (tracing) LogTrace(frame,len,0,par,TRUE);
+}
+
+
+void ReaderTransmit(uint8_t* frame, int len)
+{
+  // Generate parity and redirect
+  ReaderTransmitPar(frame,len,GetParity(frame,len));
+}
+
+int ReaderReceive(uint8_t* receivedAnswer)
+{
+  int samples = 0;
+  if (!GetIso14443aAnswerFromTag(receivedAnswer,100,&samples,0)) return FALSE;
+  if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
+  return TRUE;
+}
+
+//-----------------------------------------------------------------------------
+// Read an ISO 14443a tag. Send out commands and store answers.
+//
+//-----------------------------------------------------------------------------
+void ReaderIso14443a(uint32_t parameter)
+{
+       // Anticollision
+       uint8_t wupa[]       = { 0x52 };
+       uint8_t sel_all[]    = { 0x93,0x20 };
+       uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+       uint8_t sel_all_c2[] = { 0x95,0x20 };
+       uint8_t sel_uid_c2[] = { 0x95,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+
+       // Mifare AUTH
+       uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
+//     uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00 };
+
+  uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560);      // was 3560 - tied to other size changes
+  traceLen = 0;
+
+       // Setup SSC
+       FpgaSetupSsc();
+
+       // Start from off (no field generated)
+  // Signal field is off with the appropriate LED
+  LED_D_OFF();
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+  SpinDelay(200);
+
+  SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+  FpgaSetupSsc();
+
+       // Now give it time to spin up.
+  // Signal field is on with the appropriate LED
+  LED_D_ON();
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+       SpinDelay(200);
+
+       LED_A_ON();
+       LED_B_OFF();
+       LED_C_OFF();
+
+       while(traceLen < TRACE_LENGTH)
+  {
+    // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+    ReaderTransmitShort(wupa);
+
+    // Test if the action was cancelled
+    if(BUTTON_PRESS()) {
+      break;
+    }
+
+    // Receive the ATQA
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+    // Transmit SELECT_ALL
+    ReaderTransmit(sel_all,sizeof(sel_all));
+
+    // Receive the UID
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+               // Construct SELECT UID command
+               // First copy the 5 bytes (Mifare Classic) after the 93 70
+               memcpy(sel_uid+2,receivedAnswer,5);
+               // Secondly compute the two CRC bytes at the end
+    AppendCrc14443a(sel_uid,7);
+
+    // Transmit SELECT_UID
+    ReaderTransmit(sel_uid,sizeof(sel_uid));
+
+    // Receive the SAK
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+    // OK we have selected at least at cascade 1, lets see if first byte of UID was 0x88 in
+    // which case we need to make a cascade 2 request and select - this is a long UID
+    // When the UID is not complete, the 3nd bit (from the right) is set in the SAK.
+               if (receivedAnswer[0] &= 0x04)
+               {
+      // Transmit SELECT_ALL
+      ReaderTransmit(sel_all_c2,sizeof(sel_all_c2));
+
+      // Receive the UID
+      if (!ReaderReceive(receivedAnswer)) continue;
+
+      // Construct SELECT UID command
+      memcpy(sel_uid_c2+2,receivedAnswer,5);
+      // Secondly compute the two CRC bytes at the end
+      AppendCrc14443a(sel_uid_c2,7);
+
+      // Transmit SELECT_UID
+      ReaderTransmit(sel_uid_c2,sizeof(sel_uid_c2));
+
+      // Receive the SAK
+      if (!ReaderReceive(receivedAnswer)) continue;
+               }
+
+    // Transmit MIFARE_CLASSIC_AUTH
+    ReaderTransmit(mf_auth,sizeof(mf_auth));
+
+    // Receive the (16 bit) "random" nonce
+    if (!ReaderReceive(receivedAnswer)) continue;
+       }
+
+  // Thats it...
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       LEDsoff();
+       Dbprintf("%x %x %x", rsamples, 0xCC, 0xCC);
+       DbpString("ready..");
+}
+
+//-----------------------------------------------------------------------------
+// Read an ISO 14443a tag. Send out commands and store answers.
+//
+//-----------------------------------------------------------------------------
+void ReaderMifare(uint32_t parameter)
+{
+
+       // Anticollision
+       uint8_t wupa[]       = { 0x52 };
+       uint8_t sel_all[]    = { 0x93,0x20 };
+       uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+
+       // Mifare AUTH
+       uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
+  uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+
+  uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560);      // was 3560 - tied to other size changes
+  traceLen = 0;
+  tracing = false;
+
+       // Setup SSC
+       FpgaSetupSsc();
+
+       // Start from off (no field generated)
+  // Signal field is off with the appropriate LED
+  LED_D_OFF();
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+  SpinDelay(200);
+
+  SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+  FpgaSetupSsc();
+
+       // Now give it time to spin up.
+  // Signal field is on with the appropriate LED
+  LED_D_ON();
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+       SpinDelay(200);
+
+       LED_A_ON();
+       LED_B_OFF();
+       LED_C_OFF();
+
+  // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+  ReaderTransmitShort(wupa);
+  // Receive the ATQA
+  ReaderReceive(receivedAnswer);
+  // Transmit SELECT_ALL
+  ReaderTransmit(sel_all,sizeof(sel_all));
+  // Receive the UID
+  ReaderReceive(receivedAnswer);
+  // Construct SELECT UID command
+  // First copy the 5 bytes (Mifare Classic) after the 93 70
+  memcpy(sel_uid+2,receivedAnswer,5);
+  // Secondly compute the two CRC bytes at the end
+  AppendCrc14443a(sel_uid,7);
+
+  byte_t nt_diff = 0;
+  LED_A_OFF();
+  byte_t par = 0;
+  byte_t par_mask = 0xff;
+  byte_t par_low = 0;
+  int led_on = TRUE;
+
+  tracing = FALSE;
+  byte_t nt[4];
+  byte_t nt_attacked[4];
+  byte_t par_list[8];
+  byte_t ks_list[8];
+  num_to_bytes(parameter,4,nt_attacked);
+
+  while(TRUE)
+  {
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+    SpinDelay(200);
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+
+    // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+    ReaderTransmitShort(wupa);
+
+    // Test if the action was cancelled
+    if(BUTTON_PRESS()) {
+      break;
+    }
+
+    // Receive the ATQA
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+    // Transmit SELECT_ALL
+    ReaderTransmit(sel_all,sizeof(sel_all));
+
+    // Receive the UID
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+    // Transmit SELECT_UID
+    ReaderTransmit(sel_uid,sizeof(sel_uid));
+
+    // Receive the SAK
+    if (!ReaderReceive(receivedAnswer)) continue;
+
+    // Transmit MIFARE_CLASSIC_AUTH
+    ReaderTransmit(mf_auth,sizeof(mf_auth));
+
+    // Receive the (16 bit) "random" nonce
+    if (!ReaderReceive(receivedAnswer)) continue;
+    memcpy(nt,receivedAnswer,4);
+
+    // Transmit reader nonce and reader answer
+    ReaderTransmitPar(mf_nr_ar,sizeof(mf_nr_ar),par);
+
+    // Receive 4 bit answer
+    if (ReaderReceive(receivedAnswer))
+    {
+      if (nt_diff == 0)
+      {
+        LED_A_ON();
+        memcpy(nt_attacked,nt,4);
+        par_mask = 0xf8;
+        par_low = par & 0x07;
+      }
+
+      if (memcmp(nt,nt_attacked,4) != 0) continue;
+
+      led_on = !led_on;
+      if(led_on) LED_B_ON(); else LED_B_OFF();
+      par_list[nt_diff] = par;
+      ks_list[nt_diff] = receivedAnswer[0]^0x05;
+
+      // Test if the information is complete
+      if (nt_diff == 0x07) break;
+
+      nt_diff = (nt_diff+1) & 0x07;
+      mf_nr_ar[3] = nt_diff << 5;
+      par = par_low;
+    } else {
+      if (nt_diff == 0)
+      {
+        par++;
+      } else {
+        par = (((par>>3)+1) << 3) | par_low;
+      }
+    }
+  }
+
+  LogTraceInfo(sel_uid+2,4);
+  LogTraceInfo(nt,4);
+  LogTraceInfo(par_list,8);
+  LogTraceInfo(ks_list,8);
+
+  // Thats it...
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       LEDsoff();
+  tracing = TRUE;
+}
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