]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/iso15693.c
Upgrade crapto1 library to v3.3 (#232)
[proxmark3-svn] / armsrc / iso15693.c
index 2592cbfe6c2416359ccbd7e85893eecc615cc5aa..9a6ef9f01220a5d52fe441b7e16ae82e70affcb7 100644 (file)
-//-----------------------------------------------------------------------------\r
-// Routines to support ISO 15693. This includes both the reader software and\r
-// the `fake tag' modes, but at the moment I've implemented only the reader\r
-// stuff, and that barely.\r
-// Jonathan Westhues, split Nov 2006\r
-\r
-// Modified by Greg Jones, Jan 2009 to perform modulation onboard in arm rather than on PC\r
-// Also added additional reader commands (SELECT, READ etc.)\r
-\r
-//-----------------------------------------------------------------------------\r
-#include <proxmark3.h>\r
-#include "apps.h"\r
-#include <stdio.h>\r
-#include <stdlib.h>\r
-\r
-// FROM winsrc\prox.h //////////////////////////////////\r
-#define arraylen(x) (sizeof(x)/sizeof((x)[0]))\r
-\r
-//-----------------------------------------------------------------------------\r
-// Map a sequence of octets (~layer 2 command) into the set of bits to feed\r
-// to the FPGA, to transmit that command to the tag.\r
-//-----------------------------------------------------------------------------\r
-\r
-       \r
-\r
-\r
-       // The sampling rate is 106.353 ksps/s, for T = 18.8 us\r
-\r
-       // SOF defined as \r
-       // 1) Unmodulated time of 56.64us\r
-       // 2) 24 pulses of 423.75khz\r
-       // 3) logic '1' (unmodulated for 18.88us followed by 8 pulses of 423.75khz)\r
-\r
-       static const int FrameSOF[] = {\r
-               -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,\r
-               -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,\r
-                1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,\r
-                1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,\r
-               -1, -1, -1, -1,\r
-               -1, -1, -1, -1,\r
-                1,  1,  1,  1,\r
-                1,  1,  1,  1\r
-       };\r
-       static const int Logic0[] = {\r
-                1,  1,  1,  1,\r
-                1,  1,  1,  1,\r
-               -1, -1, -1, -1,\r
-               -1, -1, -1, -1\r
-       };\r
-       static const int Logic1[] = {\r
-               -1, -1, -1, -1,\r
-               -1, -1, -1, -1,\r
-                1,  1,  1,  1,\r
-                1,  1,  1,  1\r
-       };\r
-\r
-       // EOF defined as \r
-       // 1) logic '0' (8 pulses of 423.75khz followed by unmodulated for 18.88us)\r
-       // 2) 24 pulses of 423.75khz\r
-       // 3) Unmodulated time of 56.64us\r
-\r
-       static const int FrameEOF[] = {\r
-                1,  1,  1,  1,\r
-                1,  1,  1,  1,\r
-               -1, -1, -1, -1,\r
-               -1, -1, -1, -1,\r
-                1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,\r
-                1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,\r
-               -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,\r
-               -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1\r
-       };\r
-\r
-\r
-\r
-\r
-static void CodeIso15693AsReader(BYTE *cmd, int n)\r
-{\r
-       int i, j;\r
-\r
-       ToSendReset();\r
-\r
-       // Give it a bit of slack at the beginning\r
-       for(i = 0; i < 24; i++) {\r
-               ToSendStuffBit(1);\r
-       }\r
-\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(1);\r
-       for(i = 0; i < n; i++) {\r
-               for(j = 0; j < 8; j += 2) {\r
-                       int these = (cmd[i] >> j) & 3;\r
-                       switch(these) {\r
-                               case 0:\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(0);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       break;\r
-                               case 1:\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(0);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       break;\r
-                               case 2:\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(0);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       break;\r
-                               case 3:\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(1);\r
-                                       ToSendStuffBit(0);\r
-                                       break;\r
-                       }\r
-               }\r
-       }\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(1);\r
-       ToSendStuffBit(0);\r
-       ToSendStuffBit(1);\r
-\r
-       // And slack at the end, too.\r
-       for(i = 0; i < 24; i++) {\r
-               ToSendStuffBit(1);\r
-       }\r
-}\r
-\r
-//-----------------------------------------------------------------------------\r
-// The CRC used by ISO 15693.\r
-//-----------------------------------------------------------------------------\r
-static WORD Crc(BYTE *v, int n)\r
-{\r
-       DWORD reg;\r
-       int i, j;\r
-\r
-       reg = 0xffff;\r
-       for(i = 0; i < n; i++) {\r
-               reg = reg ^ ((DWORD)v[i]);\r
-               for (j = 0; j < 8; j++) {\r
-                       if (reg & 0x0001) {\r
-                               reg = (reg >> 1) ^ 0x8408;\r
-                       } else {\r
-                               reg = (reg >> 1);\r
-                       }\r
-               }\r
-       }\r
-\r
-       return ~reg;\r
-}\r
-\r
-////////////////////////////////////////// code to do 'itoa'\r
\r
-\r
-\r
-/* reverse:  reverse string s in place */\r
-void reverse(char s[])\r
-{\r
-    int c, i, j;\r
-\r
-    for (i = 0, j = strlen(s)-1; i<j; i++, j--) {\r
-        c = s[i];\r
-        s[i] = s[j];\r
-        s[j] = c;\r
-    }\r
-}\r
-\r
-/* itoa:  convert n to characters in s */\r
-void itoa(int n, char s[])\r
-{\r
-    int i, sign;\r
-\r
-    if ((sign = n) < 0)  /* record sign */\r
-        n = -n;          /* make n positive */\r
-    i = 0;\r
-    do {       /* generate digits in reverse order */\r
-        s[i++] = n % 10 + '0';   /* get next digit */\r
-    } while ((n /= 10) > 0);     /* delete it */\r
-    if (sign < 0)\r
-        s[i++] = '-';\r
-    s[i] = '\0';\r
-    reverse(s);\r
-} \r
-\r
-//////////////////////////////////////// END 'itoa' CODE\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Encode (into the ToSend buffers) an identify request, which is the first\r
-// thing that you must send to a tag to get a response.\r
-//-----------------------------------------------------------------------------\r
-static void BuildIdentifyRequest(void)\r
-{\r
-       BYTE cmd[5];\r
-\r
-       WORD crc;\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       // AFI is at bit 5 (1<<4) when doing an INVENTORY\r
-       cmd[0] = (1 << 2) | (1 << 5) | (1 << 1); \r
-       // inventory command code\r
-       cmd[1] = 0x01;\r
-       // no mask\r
-       cmd[2] = 0x00;\r
-       //Now the CRC\r
-       crc = Crc(cmd, 3);\r
-       cmd[3] = crc & 0xff;\r
-       cmd[4] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-static void BuildSysInfoRequest(BYTE *uid)\r
-{\r
-       BYTE cmd[12];\r
-\r
-       WORD crc;\r
-       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block\r
-       // followed by teh block data\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       cmd[0] =  (1 << 5) | (1 << 1); // no SELECT bit\r
-       // System Information command code\r
-       cmd[1] = 0x2B;\r
-       // UID may be optionally specified here\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0; // always e0 (not exactly unique)         \r
-       //Now the CRC\r
-       crc = Crc(cmd, 10); // the crc needs to be calculated over 2 bytes \r
-       cmd[10] = crc & 0xff;\r
-       cmd[11] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-static void BuildSelectRequest( BYTE uid[])\r
-{\r
-       \r
-//     uid[6]=0x31;  // this is getting ignored - the uid array is not happening...\r
-       BYTE cmd[12];\r
-\r
-       WORD crc;\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       //cmd[0] = (1 << 2) | (1 << 5) | (1 << 1);      // INVENTROY FLAGS\r
-       cmd[0] = (1 << 4) | (1 << 5) | (1 << 1);        // Select and addressed FLAGS\r
-       // SELECT command code\r
-       cmd[1] = 0x25;\r
-       // 64-bit UID\r
-//     cmd[2] = uid[0];//0x32;\r
-//     cmd[3]= uid[1];//0x4b;\r
-//     cmd[4] = uid[2];//0x03;\r
-//     cmd[5] = uid[3];//0x01;\r
-//     cmd[6] = uid[4];//0x00;\r
-//     cmd[7] = uid[5];//0x10;\r
-//     cmd[8] = uid[6];//0x05; \r
-       cmd[2] = 0x32;//\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; // infineon?\r
-\r
-       cmd[9]= 0xe0; // always e0 (not exactly unique) \r
-\r
-//     DbpIntegers(cmd[8],cmd[7],cmd[6]);\r
-       // Now the CRC\r
-       crc = Crc(cmd, 10); // the crc needs to be calculated over 10 bytes \r
-       cmd[10] = crc & 0xff;\r
-       cmd[11] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-static void BuildReadBlockRequest(BYTE *uid, BYTE blockNumber )\r
-{\r
-       BYTE cmd[13];\r
-\r
-       WORD crc;\r
-       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block\r
-       // followed by teh block data\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       cmd[0] = (1 << 6)| (1 << 5) | (1 << 1); // no SELECT bit\r
-       // READ BLOCK command code\r
-       cmd[1] = 0x20;\r
-       // UID may be optionally specified here\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0; // always e0 (not exactly unique)         \r
-       // Block number to read\r
-       cmd[10] = blockNumber;//0x00;\r
-       //Now the CRC\r
-       crc = Crc(cmd, 11); // the crc needs to be calculated over 2 bytes \r
-       cmd[11] = crc & 0xff;\r
-       cmd[12] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-\r
-static void BuildReadMultiBlockRequest(BYTE *uid)\r
-{\r
-       BYTE cmd[14];\r
-\r
-       WORD crc;\r
-       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block\r
-       // followed by teh block data\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       cmd[0] =  (1 << 5) | (1 << 1); // no SELECT bit\r
-       // READ Multi BLOCK command code\r
-       cmd[1] = 0x23;\r
-       // UID may be optionally specified here\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0; // always e0 (not exactly unique)         \r
-       // First Block number to read\r
-       cmd[10] = 0x00;\r
-       // Number of Blocks to read\r
-       cmd[11] = 0x2f; // read quite a few\r
-       //Now the CRC\r
-       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes \r
-       cmd[12] = crc & 0xff;\r
-       cmd[13] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-static void BuildArbitraryRequest(BYTE *uid,BYTE CmdCode)\r
-{\r
-       BYTE cmd[14];\r
-\r
-       WORD crc;\r
-       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block\r
-       // followed by teh block data\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       cmd[0] =   (1 << 5) | (1 << 1); // no SELECT bit\r
-       // READ BLOCK command code\r
-       cmd[1] = CmdCode;\r
-       // UID may be optionally specified here\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0; // always e0 (not exactly unique)         \r
-       // Parameter\r
-       cmd[10] = 0x00;\r
-       cmd[11] = 0x0a;\r
-\r
-//     cmd[12] = 0x00;\r
-//     cmd[13] = 0x00; //Now the CRC\r
-       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes \r
-       cmd[12] = crc & 0xff;\r
-       cmd[13] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-static void BuildArbitraryCustomRequest(BYTE *uid,BYTE CmdCode)\r
-{\r
-       BYTE cmd[14];\r
-\r
-       WORD crc;\r
-       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block\r
-       // followed by teh block data\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       cmd[0] =   (1 << 5) | (1 << 1); // no SELECT bit\r
-       // READ BLOCK command code\r
-       cmd[1] = CmdCode;\r
-       // UID may be optionally specified here\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0; // always e0 (not exactly unique)         \r
-       // Parameter\r
-       cmd[10] = 0x05; // for custom codes this must be manufcturer code\r
-       cmd[11] = 0x00;\r
-\r
-//     cmd[12] = 0x00;\r
-//     cmd[13] = 0x00; //Now the CRC\r
-       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes \r
-       cmd[12] = crc & 0xff;\r
-       cmd[13] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-/////////////////////////////////////////////////////////////////////////\r
-// Now the VICC>VCD responses when we are simulating a tag\r
-////////////////////////////////////////////////////////////////////\r
-\r
- static void BuildInventoryResponse(void)\r
-{\r
-       BYTE cmd[12];\r
-\r
-       WORD crc;\r
-       // one sub-carrier, inventory, 1 slot, fast rate\r
-       // AFI is at bit 5 (1<<4) when doing an INVENTORY\r
-       cmd[0] = 0; //(1 << 2) | (1 << 5) | (1 << 1); \r
-       cmd[1] = 0;\r
-       // 64-bit UID\r
-       cmd[2] = 0x32;\r
-       cmd[3]= 0x4b;\r
-       cmd[4] = 0x03;\r
-       cmd[5] = 0x01;\r
-       cmd[6] = 0x00;\r
-       cmd[7] = 0x10;\r
-       cmd[8] = 0x05; \r
-       cmd[9]= 0xe0;\r
-       //Now the CRC\r
-       crc = Crc(cmd, 10);\r
-       cmd[10] = crc & 0xff;\r
-       cmd[11] = crc >> 8;\r
-\r
-       CodeIso15693AsReader(cmd, sizeof(cmd));\r
-}\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Transmit the command (to the tag) that was placed in ToSend[].\r
-//-----------------------------------------------------------------------------\r
-static void TransmitTo15693Tag(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
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);\r
-       if(*wait < 10) { *wait = 10; }\r
-\r
-//    for(c = 0; c < *wait;) {\r
-//        if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-//            SSC_TRANSMIT_HOLDING = 0x00;             // For exact timing!\r
-//            c++;\r
-//        }\r
-//        if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-//            volatile DWORD r = SSC_RECEIVE_HOLDING;\r
-//            (void)r;\r
-//        }\r
-//        WDT_HIT();\r
-//    }\r
-\r
-    c = 0;\r
-    for(;;) {\r
-        if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-            SSC_TRANSMIT_HOLDING = cmd[c];\r
-            c++;\r
-            if(c >= len) {\r
-                break;\r
-            }\r
-        }\r
-        if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-            volatile DWORD r = SSC_RECEIVE_HOLDING;\r
-            (void)r;\r
-        }\r
-        WDT_HIT();\r
-    }\r
-       *samples = (c + *wait) << 3;\r
-}\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Transmit the command (to the reader) that was placed in ToSend[].\r
-//-----------------------------------------------------------------------------\r
-static void TransmitTo15693Reader(const BYTE *cmd, int len, int *samples, int *wait)\r
-{\r
-    int c;\r
-\r
-//     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR);        // No requirement to energise my coils\r
-       if(*wait < 10) { *wait = 10; }\r
-\r
-    c = 0;\r
-    for(;;) {\r
-        if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-            SSC_TRANSMIT_HOLDING = cmd[c];\r
-            c++;\r
-            if(c >= len) {\r
-                break;\r
-            }\r
-        }\r
-        if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-            volatile DWORD r = SSC_RECEIVE_HOLDING;\r
-            (void)r;\r
-        }\r
-        WDT_HIT();\r
-    }\r
-       *samples = (c + *wait) << 3;\r
-}\r
-\r
-\r
-\r
-\r
-\r
-\r
-static int GetIso15693AnswerFromTag(BYTE *receivedResponse, int maxLen, int *samples, int *elapsed) \r
-{\r
-       int c = 0;\r
-       BYTE *dest = (BYTE *)BigBuf;\r
-       int getNext = 0;\r
-\r
-\r
-       SBYTE prev = 0;\r
-\r
-// NOW READ RESPONSE\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);\r
-       //spindelay(60);        // greg - experiment to get rid of some of the 0 byte/failed reads\r
-       c = 0;\r
-       getNext = FALSE;\r
-       for(;;) {\r
-               if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-                       SSC_TRANSMIT_HOLDING = 0x43;\r
-               }\r
-               if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-                       SBYTE b;\r
-                       b = (SBYTE)SSC_RECEIVE_HOLDING;\r
-\r
-                       // The samples are correlations against I and Q versions of the\r
-                       // tone that the tag AM-modulates, so every other sample is I,\r
-                       // every other is Q. We just want power, so abs(I) + abs(Q) is\r
-                       // close to what we want.\r
-                       if(getNext) {\r
-                               SBYTE r;\r
-\r
-                               if(b < 0) {\r
-                                       r = -b;\r
-                               } else {\r
-                                       r = b;\r
-                               }\r
-                               if(prev < 0) {\r
-                                       r -= prev;\r
-                               } else {\r
-                                       r += prev;\r
-                               }\r
-\r
-                               dest[c++] = (BYTE)r;\r
-\r
-                               if(c >= 2000) {\r
-                                       break;\r
-                               }\r
-                       } else {\r
-                               prev = b;\r
-                       }\r
-\r
-                       getNext = !getNext;\r
-               }\r
-       }\r
-\r
-//////////////////////////////////////////\r
-/////////// DEMODULATE ///////////////////\r
-//////////////////////////////////////////\r
-\r
-       int i, j;\r
-       int max = 0, maxPos;\r
-\r
-       int skip = 4;\r
-\r
-\r
-//     if(GraphTraceLen < 1000) return;        // THIS CHECKS FOR A BUFFER TO SMALL\r
-\r
-       // First, correlate for SOF\r
-       for(i = 0; i < 100; i++) {\r
-               int corr = 0;\r
-               for(j = 0; j < arraylen(FrameSOF); j += skip) {\r
-                       corr += FrameSOF[j]*dest[i+(j/skip)];\r
-               }\r
-               if(corr > max) {\r
-                       max = corr;\r
-                       maxPos = i;\r
-               }\r
-       }\r
-//     DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip));\r
-\r
-       int k = 0; // this will be our return value\r
-\r
-       // greg - If correlation is less than 1 then there's little point in continuing\r
-       if ((max/(arraylen(FrameSOF)/skip)) >= 1) \r
-       {\r
-\r
-       i = maxPos + arraylen(FrameSOF)/skip;\r
-       \r
-       BYTE outBuf[20];\r
-       memset(outBuf, 0, sizeof(outBuf));\r
-       BYTE mask = 0x01;\r
-       for(;;) {\r
-               int corr0 = 0, corr1 = 0, corrEOF = 0;\r
-               for(j = 0; j < arraylen(Logic0); j += skip) {\r
-                       corr0 += Logic0[j]*dest[i+(j/skip)];\r
-               }\r
-               for(j = 0; j < arraylen(Logic1); j += skip) {\r
-                       corr1 += Logic1[j]*dest[i+(j/skip)];\r
-               }\r
-               for(j = 0; j < arraylen(FrameEOF); j += skip) {\r
-                       corrEOF += FrameEOF[j]*dest[i+(j/skip)];\r
-               }\r
-               // Even things out by the length of the target waveform.\r
-               corr0 *= 4;\r
-               corr1 *= 4;\r
-\r
-               if(corrEOF > corr1 && corrEOF > corr0) {\r
-//                     DbpString("EOF at %d", i);\r
-                       break;\r
-               } else if(corr1 > corr0) {\r
-                       i += arraylen(Logic1)/skip;\r
-                       outBuf[k] |= mask;\r
-               } else {\r
-                       i += arraylen(Logic0)/skip;\r
-               }\r
-               mask <<= 1;\r
-               if(mask == 0) {\r
-                       k++;\r
-                       mask = 0x01;\r
-               }\r
-               if((i+(int)arraylen(FrameEOF)) >= 2000) {\r
-                       DbpString("ran off end!");\r
-                       break;\r
-               }\r
-       }\r
-       if(mask != 0x01) {\r
-               DbpString("error, uneven octet! (discard extra bits!)");\r
-///            DbpString("   mask=%02x", mask);\r
-       }\r
-//     BYTE str1 [8];\r
-//     itoa(k,str1);\r
-//     strcat(str1," octets read");\r
-\r
-//     DbpString(  str1);    // DbpString("%d octets", k);\r
-\r
-//     for(i = 0; i < k; i+=3) {\r
-//             //DbpString("# %2d: %02x ", i, outBuf[i]);\r
-//             DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);\r
-//     }\r
-\r
-       for(i = 0; i < k; i++) {\r
-               receivedResponse[i] = outBuf[i];\r
-       }       \r
-       } // "end if correlation > 0"   (max/(arraylen(FrameSOF)/skip))\r
-       return k; // return the number of bytes demodulated\r
-\r
-///    DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));\r
-\r
-\r
-}\r
-\r
-// Now the GetISO15693 message from sniffing command\r
-static int GetIso15693AnswerFromSniff(BYTE *receivedResponse, int maxLen, int *samples, int *elapsed) \r
-{\r
-       int c = 0;\r
-       BYTE *dest = (BYTE *)BigBuf;\r
-       int getNext = 0;\r
-\r
-\r
-       SBYTE prev = 0;\r
-\r
-// NOW READ RESPONSE\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);\r
-       //spindelay(60);        // greg - experiment to get rid of some of the 0 byte/failed reads\r
-       c = 0;\r
-       getNext = FALSE;\r
-       for(;;) {\r
-               if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-                       SSC_TRANSMIT_HOLDING = 0x43;\r
-               }\r
-               if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-                       SBYTE b;\r
-                       b = (SBYTE)SSC_RECEIVE_HOLDING;\r
-\r
-                       // The samples are correlations against I and Q versions of the\r
-                       // tone that the tag AM-modulates, so every other sample is I,\r
-                       // every other is Q. We just want power, so abs(I) + abs(Q) is\r
-                       // close to what we want.\r
-                       if(getNext) {\r
-                               SBYTE r;\r
-\r
-                               if(b < 0) {\r
-                                       r = -b;\r
-                               } else {\r
-                                       r = b;\r
-                               }\r
-                               if(prev < 0) {\r
-                                       r -= prev;\r
-                               } else {\r
-                                       r += prev;\r
-                               }\r
-\r
-                               dest[c++] = (BYTE)r;\r
-\r
-                               if(c >= 20000) {\r
-                                       break;\r
-                               }\r
-                       } else {\r
-                               prev = b;\r
-                       }\r
-\r
-                       getNext = !getNext;\r
-               }\r
-       }\r
-\r
-//////////////////////////////////////////\r
-/////////// DEMODULATE ///////////////////\r
-//////////////////////////////////////////\r
-\r
-       int i, j;\r
-       int max = 0, maxPos;\r
-\r
-       int skip = 4;\r
-\r
-\r
-//     if(GraphTraceLen < 1000) return;        // THIS CHECKS FOR A BUFFER TO SMALL\r
-\r
-       // First, correlate for SOF\r
-       for(i = 0; i < 19000; i++) {\r
-               int corr = 0;\r
-               for(j = 0; j < arraylen(FrameSOF); j += skip) {\r
-                       corr += FrameSOF[j]*dest[i+(j/skip)];\r
-               }\r
-               if(corr > max) {\r
-                       max = corr;\r
-                       maxPos = i;\r
-               }\r
-       }\r
-//     DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip));\r
-\r
-       int k = 0; // this will be our return value\r
-\r
-       // greg - If correlation is less than 1 then there's little point in continuing\r
-       if ((max/(arraylen(FrameSOF)/skip)) >= 1)       // THIS SHOULD BE 1 \r
-       {\r
-\r
-       i = maxPos + arraylen(FrameSOF)/skip;\r
-       \r
-       BYTE outBuf[20];\r
-       memset(outBuf, 0, sizeof(outBuf));\r
-       BYTE mask = 0x01;\r
-       for(;;) {\r
-               int corr0 = 0, corr1 = 0, corrEOF = 0;\r
-               for(j = 0; j < arraylen(Logic0); j += skip) {\r
-                       corr0 += Logic0[j]*dest[i+(j/skip)];\r
-               }\r
-               for(j = 0; j < arraylen(Logic1); j += skip) {\r
-                       corr1 += Logic1[j]*dest[i+(j/skip)];\r
-               }\r
-               for(j = 0; j < arraylen(FrameEOF); j += skip) {\r
-                       corrEOF += FrameEOF[j]*dest[i+(j/skip)];\r
-               }\r
-               // Even things out by the length of the target waveform.\r
-               corr0 *= 4;\r
-               corr1 *= 4;\r
-\r
-               if(corrEOF > corr1 && corrEOF > corr0) {\r
-//                     DbpString("EOF at %d", i);\r
-                       break;\r
-               } else if(corr1 > corr0) {\r
-                       i += arraylen(Logic1)/skip;\r
-                       outBuf[k] |= mask;\r
-               } else {\r
-                       i += arraylen(Logic0)/skip;\r
-               }\r
-               mask <<= 1;\r
-               if(mask == 0) {\r
-                       k++;\r
-                       mask = 0x01;\r
-               }\r
-               if((i+(int)arraylen(FrameEOF)) >= 2000) {\r
-                       DbpString("ran off end!");\r
-                       break;\r
-               }\r
-       }\r
-       if(mask != 0x01) {\r
-               DbpString("error, uneven octet! (discard extra bits!)");\r
-///            DbpString("   mask=%02x", mask);\r
-       }\r
-//     BYTE str1 [8];\r
-//     itoa(k,str1);\r
-//     strcat(str1," octets read");\r
-\r
-//     DbpString(  str1);    // DbpString("%d octets", k);\r
-\r
-//     for(i = 0; i < k; i+=3) {\r
-//             //DbpString("# %2d: %02x ", i, outBuf[i]);\r
-//             DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);\r
-//     }\r
-\r
-       for(i = 0; i < k; i++) {\r
-               receivedResponse[i] = outBuf[i];\r
-       }       \r
-       } // "end if correlation > 0"   (max/(arraylen(FrameSOF)/skip))\r
-       return k; // return the number of bytes demodulated\r
-\r
-///    DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));\r
-\r
-\r
-}\r
-\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Start to read an ISO 15693 tag. We send an identify request, then wait\r
-// for the response. The response is not demodulated, just left in the buffer\r
-// so that it can be downloaded to a PC and processed there.\r
-//-----------------------------------------------------------------------------\r
-void AcquireRawAdcSamplesIso15693(void)\r
-{\r
-       int c = 0;\r
-       BYTE *dest = (BYTE *)BigBuf;\r
-       int getNext = 0;\r
-\r
-       SBYTE prev = 0;\r
-\r
-       BuildIdentifyRequest();\r
-\r
-       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-\r
-       // Give the tags time to energize\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);\r
-       SpinDelay(100);\r
-\r
-       // Now send the command\r
-       FpgaSetupSsc();\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);\r
-\r
-       c = 0;\r
-       for(;;) {\r
-               if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-                       SSC_TRANSMIT_HOLDING = ToSend[c];\r
-                       c++;\r
-                       if(c == ToSendMax+3) {\r
-                               break;\r
-                       }\r
-               }\r
-               if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-                       volatile DWORD r = SSC_RECEIVE_HOLDING;\r
-                       (void)r;\r
-               }\r
-               WDT_HIT();\r
-       }\r
-\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);\r
-\r
-       c = 0;\r
-       getNext = FALSE;\r
-       for(;;) {\r
-               if(SSC_STATUS & (SSC_STATUS_TX_READY)) {\r
-                       SSC_TRANSMIT_HOLDING = 0x43;\r
-               }\r
-               if(SSC_STATUS & (SSC_STATUS_RX_READY)) {\r
-                       SBYTE b;\r
-                       b = (SBYTE)SSC_RECEIVE_HOLDING;\r
-\r
-                       // The samples are correlations against I and Q versions of the\r
-                       // tone that the tag AM-modulates, so every other sample is I,\r
-                       // every other is Q. We just want power, so abs(I) + abs(Q) is\r
-                       // close to what we want.\r
-                       if(getNext) {\r
-                               SBYTE r;\r
-\r
-                               if(b < 0) {\r
-                                       r = -b;\r
-                               } else {\r
-                                       r = b;\r
-                               }\r
-                               if(prev < 0) {\r
-                                       r -= prev;\r
-                               } else {\r
-                                       r += prev;\r
-                               }\r
-\r
-                               dest[c++] = (BYTE)r;\r
-\r
-                               if(c >= 2000) {\r
-                                       break;\r
-                               }\r
-                       } else {\r
-                               prev = b;\r
-                       }\r
-\r
-                       getNext = !getNext;\r
-               }\r
-       }\r
-}\r
-\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector\r
-// all demodulation performed in arm rather than host. - greg\r
-//-----------------------------------------------------------------------------\r
-void ReaderIso15693(DWORD parameter)\r
-{\r
-       LED_A_ON();\r
-       LED_B_ON();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-\r
-\r
-//DbpString(parameter);\r
-\r
-       BYTE *receivedAnswer0 = (((BYTE *)BigBuf) + 3560); // allow 100 bytes per reponse (way too much)\r
-       BYTE *receivedAnswer1 = (((BYTE *)BigBuf) + 3660); // \r
-       BYTE *receivedAnswer2 = (((BYTE *)BigBuf) + 3760);\r
-       BYTE *receivedAnswer3 = (((BYTE *)BigBuf) + 3860);\r
-       //BYTE *TagUID= (((BYTE *)BigBuf) + 3960);              // where we hold the uid for hi15reader \r
-       int responseLen0 = 0;\r
-       int responseLen1 = 0;\r
-       int responseLen2 = 0;\r
-       int responseLen3 = 0;\r
-\r
-       // Blank arrays\r
-       int j;\r
-       for(j = 0; j < 100; j++) {\r
-               receivedAnswer3[j] = 0;\r
-               receivedAnswer2[j] =0;\r
-               receivedAnswer1[j] = 0;\r
-               receivedAnswer0[j] = 0;\r
-       }\r
-\r
-       // Setup SSC\r
-       FpgaSetupSsc();\r
-\r
-       // Start from off (no field generated)\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);\r
-       SpinDelay(200);\r
-\r
-       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-       FpgaSetupSsc();\r
-\r
-       // Give the tags time to energize\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);\r
-       SpinDelay(200);\r
-\r
-       LED_A_ON();\r
-       LED_B_OFF();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-\r
-       int samples = 0;\r
-       int tsamples = 0;\r
-       int wait = 0;\r
-       int elapsed = 0;\r
-\r
-       // FIRST WE RUN AN INVENTORY TO GET THE TAG UID\r
-       // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME\r
- BYTE TagUID[7];               // where we hold the uid for hi15reader \r
-\r
-\r
-//     BuildIdentifyRequest();\r
-//     //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait);      \r
-//     TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  // No longer ToSendMax+3\r
-//     // Now wait for a response\r
-//     responseLen0 = GetIso15693AnswerFromTag(receivedAnswer0, 100, &samples, &elapsed) ;     \r
-//     if (responseLen0 >=12) // we should do a better check than this\r
-//     {\r
-//             // really we should check it is a valid mesg\r
-//             // but for now just grab what we think is the uid\r
-//             TagUID[0] = receivedAnswer0[2];\r
-//             TagUID[1] = receivedAnswer0[3];\r
-//             TagUID[2] = receivedAnswer0[4];\r
-//             TagUID[3] = receivedAnswer0[5];\r
-//             TagUID[4] = receivedAnswer0[6];\r
-//             TagUID[5] = receivedAnswer0[7];\r
-//             TagUID[6] = receivedAnswer0[8]; // IC Manufacturer code\r
-//     DbpIntegers(TagUID[6],TagUID[5],TagUID[4]);     \r
-//}\r
-\r
-       // Now send the IDENTIFY command\r
-       BuildIdentifyRequest();\r
-       //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait);      \r
-       TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  // No longer ToSendMax+3\r
-       // Now wait for a response\r
-       responseLen1 = GetIso15693AnswerFromTag(receivedAnswer1, 100, &samples, &elapsed) ;\r
-       \r
-       if (responseLen1 >=12) // we should do a better check than this\r
-       {\r
-               \r
-               TagUID[0] = receivedAnswer1[2];\r
-               TagUID[1] = receivedAnswer1[3];\r
-               TagUID[2] = receivedAnswer1[4];\r
-               TagUID[3] = receivedAnswer1[5];\r
-               TagUID[4] = receivedAnswer1[6];\r
-               TagUID[5] = receivedAnswer1[7];\r
-               TagUID[6] = receivedAnswer1[8]; // IC Manufacturer code\r
-               \r
-               // Now send the SELECT command\r
-               BuildSelectRequest(*TagUID);\r
-               TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  // No longer ToSendMax+3\r
-               // Now wait for a response\r
-               responseLen2 = GetIso15693AnswerFromTag(receivedAnswer2, 100, &samples, &elapsed); \r
-\r
-               // Now send the MULTI READ command\r
-//             BuildArbitraryRequest(*TagUID,parameter);\r
-               BuildArbitraryCustomRequest(*TagUID,parameter);\r
-//             BuildReadBlockRequest(*TagUID,parameter);\r
-//             BuildSysInfoRequest(*TagUID);\r
-               //TransmitTo15693Tag(ToSend,ToSendMax+3,&tsamples, &wait);      \r
-               TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  // No longer ToSendMax+3        \r
-               // Now wait for a response\r
-               responseLen3 = GetIso15693AnswerFromTag(receivedAnswer3, 100, &samples, &elapsed) ;\r
-\r
-       }\r
-\r
-\r
-\r
-       BYTE str1 [4];\r
-       //char str2 [200];\r
-       int i;\r
-\r
-       itoa(responseLen1,str1);\r
-       strcat(str1," octets read from IDENTIFY request");\r
-       DbpString(str1);\r
-       for(i = 0; i < responseLen1; i+=3) {\r
-               DbpIntegers(receivedAnswer1[i],receivedAnswer1[i+1],receivedAnswer1[i+2]);\r
-       }\r
-\r
-       itoa(responseLen2,str1);\r
-       strcat(str1," octets read from SELECT request");\r
-       DbpString(str1);\r
-       for(i = 0; i < responseLen2; i+=3) {\r
-               DbpIntegers(receivedAnswer2[i],receivedAnswer2[i+1],receivedAnswer2[i+2]);\r
-       }\r
-\r
-       itoa(responseLen3,str1);\r
-       strcat(str1," octets read from XXX request");\r
-       DbpString(str1);\r
-       for(i = 0; i < responseLen3; i+=3) {\r
-               DbpIntegers(receivedAnswer3[i],receivedAnswer3[i+1],receivedAnswer3[i+2]);\r
-       }\r
-       \r
-\r
-//     str2[0]=0;\r
-//     for(i = 0; i < responseLen3; i++) {\r
-//             itoa(str1,receivedAnswer3[i]);\r
-//             strcat(str2,str1);\r
-//     }\r
-//     DbpString(str2);        \r
-\r
-       LED_A_OFF();\r
-       LED_B_OFF();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-\r
-\r
-}\r
-\r
-\r
-\r
-//-----------------------------------------------------------------------------\r
-// Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands\r
-// all demodulation performed in arm rather than host. - greg\r
-//-----------------------------------------------------------------------------\r
-void SimTagIso15693(DWORD parameter)\r
-{\r
-       LED_A_ON();\r
-       LED_B_ON();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-\r
-\r
-//DbpString(parameter);\r
-\r
-       BYTE *receivedAnswer0 = (((BYTE *)BigBuf) + 3560); // allow 100 bytes per reponse (way too much)\r
-       BYTE *receivedAnswer1 = (((BYTE *)BigBuf) + 3660); // \r
-       BYTE *receivedAnswer2 = (((BYTE *)BigBuf) + 3760);\r
-       BYTE *receivedAnswer3 = (((BYTE *)BigBuf) + 3860);\r
-       //BYTE *TagUID= (((BYTE *)BigBuf) + 3960);              // where we hold the uid for hi15reader \r
-       int responseLen0 = 0;\r
-       int responseLen1 = 0;\r
-       int responseLen2 = 0;\r
-       int responseLen3 = 0;\r
-\r
-       // Blank arrays\r
-       int j;\r
-       for(j = 0; j < 100; j++) {\r
-               receivedAnswer3[j] = 0;\r
-               receivedAnswer2[j] =0;\r
-               receivedAnswer1[j] = 0;\r
-               receivedAnswer0[j] = 0;\r
-       }\r
-\r
-       // Setup SSC\r
-       FpgaSetupSsc();\r
-\r
-       // Start from off (no field generated)\r
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);\r
-       SpinDelay(200);\r
-\r
-       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);\r
-       FpgaSetupSsc();\r
-\r
-       // Give the tags time to energize\r
-//     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);  // NO GOOD FOR SIM TAG!!!!\r
-       SpinDelay(200);\r
-\r
-       LED_A_OFF();\r
-       LED_B_OFF();\r
-       LED_C_ON();\r
-       LED_D_OFF();\r
-\r
-       int samples = 0;\r
-       int tsamples = 0;\r
-       int wait = 0;\r
-       int elapsed = 0;\r
-\r
-       // FIRST WE RUN AN INVENTORY TO GET THE TAG UID\r
-       // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME\r
- BYTE TagUID[7];               // where we hold the uid for hi15reader \r
-\r
-\r
-\r
-       // Now send the IDENTIFY command\r
-//     BuildIdentifyRequest();\r
-//     TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  // No longer ToSendMax+3\r
-\r
-\r
-       // Now wait for a command from the reader\r
-       responseLen1=0;\r
-//     while(responseLen1=0) {\r
-//             if(BUTTON_PRESS()) break;\r
-               responseLen1 = GetIso15693AnswerFromSniff(receivedAnswer1, 100, &samples, &elapsed) ;\r
-//             }\r
-\r
-       \r
-       if (responseLen1 >=1) // we should do a better check than this\r
-       {\r
-               // Build a suitable reponse to the reader INVENTORY cocmmand\r
-               BuildInventoryResponse;\r
-               TransmitTo15693Reader(ToSend,ToSendMax,&tsamples, &wait);\r
-\r
-               // Now wait for a command from the reader\r
-//             responseLen2 = GetIso15693AnswerFromTag(receivedAnswer2, 100, &samples, &elapsed); \r
-\r
-       \r
-               // Now wait for a command from the reader\r
-//             responseLen3 = GetIso15693AnswerFromTag(receivedAnswer3, 100, &samples, &elapsed) ;\r
-\r
-       }\r
-\r
-\r
-\r
-       BYTE str1 [4];\r
-       //char str2 [200];\r
-       int i;\r
-\r
-       itoa(responseLen1,str1);\r
-       strcat(str1," octets read from reader command");\r
-       DbpString(str1);\r
-       for(i = 0; i < responseLen1; i+=3) {\r
-               DbpIntegers(receivedAnswer1[i],receivedAnswer1[i+1],receivedAnswer1[i+2]);\r
-       }\r
-\r
-//     itoa(responseLen2,str1);\r
-//     strcat(str1," octets read from SELECT request");\r
-//     DbpString(str1);\r
-//     for(i = 0; i < responseLen2; i+=3) {\r
-//             DbpIntegers(receivedAnswer2[i],receivedAnswer2[i+1],receivedAnswer2[i+2]);\r
-//     }\r
-//\r
-//     itoa(responseLen3,str1);\r
-//     strcat(str1," octets read from XXX request");\r
-//     DbpString(str1);\r
-//     for(i = 0; i < responseLen3; i+=3) {\r
-//             DbpIntegers(receivedAnswer3[i],receivedAnswer3[i+1],receivedAnswer3[i+2]);\r
-//     }\r
-       \r
-\r
-//     str2[0]=0;\r
-//     for(i = 0; i < responseLen3; i++) {\r
-//             itoa(str1,receivedAnswer3[i]);\r
-//             strcat(str2,str1);\r
-//     }\r
-//     DbpString(str2);        \r
-\r
-       LED_A_OFF();\r
-       LED_B_OFF();\r
-       LED_C_OFF();\r
-       LED_D_OFF();\r
-\r
-\r
-}
\ No newline at end of file
+//-----------------------------------------------------------------------------
+// Jonathan Westhues, split Nov 2006
+// Modified by Greg Jones, Jan 2009
+// Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// Routines to support ISO 15693. This includes both the reader software and
+// the `fake tag' modes, but at the moment I've implemented only the reader
+// stuff, and that barely.
+// Modified to perform modulation onboard in arm rather than on PC
+// Also added additional reader commands (SELECT, READ etc.)
+//-----------------------------------------------------------------------------
+// The ISO 15693 describes two transmission modes from reader to tag, and 4 
+// transmission modes from tag to reader. As of Mar 2010 this code only 
+// supports one of each: "1of4" mode from reader to tag, and the highspeed 
+// variant with one subcarrier from card to reader.
+// As long, as the card fully support ISO 15693 this is no problem, since the 
+// reader chooses both data rates, but some non-standard tags do not. Further for 
+// the simulation to work, we will need to support all data rates.
+//
+// VCD (reader) -> VICC (tag)
+// 1 out of 256:
+//     data rate: 1,66 kbit/s (fc/8192) 
+//     used for long range
+// 1 out of 4:
+//     data rate: 26,48 kbit/s (fc/512)
+//     used for short range, high speed
+// 
+// VICC (tag) -> VCD (reader)
+// Modulation:
+//             ASK / one subcarrier (423,75 khz)
+//             FSK / two subcarriers (423,75 khz && 484,28 khz)
+// Data Rates / Modes:
+//     low ASK: 6,62 kbit/s
+//     low FSK: 6.67 kbit/s
+//     high ASK: 26,48 kbit/s
+//     high FSK: 26,69 kbit/s
+//-----------------------------------------------------------------------------
+// added "1 out of 256" mode (for VCD->PICC) - atrox 20100911
+
+
+// Random Remarks:
+// *) UID is always used "transmission order" (LSB), which is reverse to display order
+
+// TODO / BUGS / ISSUES:
+// *) writing to tags takes longer: we miss the answer from the tag in most cases
+//    -> tweak the read-timeout times
+// *) signal decoding from the card is still a bit shaky. 
+// *) signal decoding is unable to detect collissions.
+// *) add anti-collission support for inventory-commands 
+// *) read security status of a block
+// *) sniffing and simulation do only support one transmission mode. need to support 
+//             all 8 transmission combinations
+//     *) remove or refactor code under "depricated"
+// *) document all the functions
+
+
+#include "proxmark3.h"
+#include "util.h"
+#include "apps.h"
+#include "string.h"
+#include "iso15693tools.h"
+#include "cmd.h"
+
+#define arraylen(x) (sizeof(x)/sizeof((x)[0]))
+
+///////////////////////////////////////////////////////////////////////
+// ISO 15693 Part 2 - Air Interface
+// This section basicly contains transmission and receiving of bits
+///////////////////////////////////////////////////////////////////////
+
+#define FrameSOF              Iso15693FrameSOF
+#define Logic0                Iso15693Logic0
+#define Logic1                Iso15693Logic1
+#define FrameEOF              Iso15693FrameEOF
+
+#define Crc(data,datalen)     Iso15693Crc(data,datalen)
+#define AddCrc(data,datalen)  Iso15693AddCrc(data,datalen)
+#define sprintUID(target,uid)  Iso15693sprintUID(target,uid)
+
+int DEBUG=0;
+
+
+// ---------------------------
+// Signal Processing 
+// ---------------------------
+
+// prepare data using "1 out of 4" code for later transmission
+// resulting data rate is 26,48 kbit/s (fc/512)
+// cmd ... data
+// n ... length of data
+static void CodeIso15693AsReader(uint8_t *cmd, int n)
+{
+       int i, j;
+
+       ToSendReset();
+
+       // Give it a bit of slack at the beginning
+       for(i = 0; i < 24; i++) {
+               ToSendStuffBit(1);
+       }
+
+       // SOF for 1of4
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       for(i = 0; i < n; i++) {
+               for(j = 0; j < 8; j += 2) {
+                       int these = (cmd[i] >> j) & 3;
+                       switch(these) {
+                               case 0:
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(0);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       break;
+                               case 1:
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(0);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       break;
+                               case 2:
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(0);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       break;
+                               case 3:
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(1);
+                                       ToSendStuffBit(0);
+                                       break;
+                       }
+               }
+       }
+       // EOF
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);
+
+       // And slack at the end, too.
+       for(i = 0; i < 24; i++) {
+               ToSendStuffBit(1);
+       }
+}
+
+// encode data using "1 out of 256" sheme
+// data rate is 1,66 kbit/s (fc/8192) 
+// is designed for more robust communication over longer distances
+static void CodeIso15693AsReader256(uint8_t *cmd, int n)
+{
+       int i, j;
+
+       ToSendReset();
+
+       // Give it a bit of slack at the beginning
+       for(i = 0; i < 24; i++) {
+               ToSendStuffBit(1);
+       }
+
+       // SOF for 1of256
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(0);
+       
+       for(i = 0; i < n; i++) {
+               for (j = 0; j<=255; j++) {
+                       if (cmd[i]==j) {
+                               ToSendStuffBit(1);
+                               ToSendStuffBit(0);
+                       } else {
+                               ToSendStuffBit(1);
+                               ToSendStuffBit(1);
+                       }                       
+               }       
+       }
+       // EOF
+       ToSendStuffBit(1);
+       ToSendStuffBit(1);
+       ToSendStuffBit(0);
+       ToSendStuffBit(1);
+
+       // And slack at the end, too.
+       for(i = 0; i < 24; i++) {
+               ToSendStuffBit(1);
+       }
+}
+
+
+// Transmit the command (to the tag) that was placed in ToSend[].
+static void TransmitTo15693Tag(const uint8_t *cmd, int len, int *samples, int *wait)
+{
+    int c;
+
+//    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);
+       if(*wait < 10) { *wait = 10; }
+
+//    for(c = 0; c < *wait;) {
+//        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+//            AT91C_BASE_SSC->SSC_THR = 0x00;          // For exact timing!
+//            c++;
+//        }
+//        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+//            volatile 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();
+    }
+       *samples = (c + *wait) << 3;
+}
+
+//-----------------------------------------------------------------------------
+// Transmit the command (to the reader) that was placed in ToSend[].
+//-----------------------------------------------------------------------------
+static void TransmitTo15693Reader(const uint8_t *cmd, int len, int *samples, int *wait)
+{
+    int c = 0;
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K);
+       if(*wait < 10) { *wait = 10; }
+
+    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();
+    }
+       *samples = (c + *wait) << 3;
+}
+
+
+// Read from Tag
+// Parameters:
+//             receivedResponse
+//             maxLen
+//             samples
+//             elapsed
+// returns: 
+//             number of decoded bytes
+static int GetIso15693AnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed)
+{
+       int c = 0;
+       uint8_t *dest = BigBuf_get_addr();
+       int getNext = 0;
+
+       int8_t prev = 0;
+
+// NOW READ RESPONSE
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+       //spindelay(60);        // greg - experiment to get rid of some of the 0 byte/failed reads
+       c = 0;
+       getNext = FALSE;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x43;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       int8_t b;
+                       b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       // The samples are correlations against I and Q versions of the
+                       // tone that the tag AM-modulates, so every other sample is I,
+                       // every other is Q. We just want power, so abs(I) + abs(Q) is
+                       // close to what we want.
+                       if(getNext) {
+                               int8_t r = ABS(b) + ABS(prev);
+
+                               dest[c++] = (uint8_t)r;
+
+                               if(c >= 2000) {
+                                       break;
+                               }
+                       } else {
+                               prev = b;
+                       }
+
+                       getNext = !getNext;
+               }
+       }
+
+       //////////////////////////////////////////
+       /////////// DEMODULATE ///////////////////
+       //////////////////////////////////////////
+
+       int i, j;
+       int max = 0, maxPos=0;
+
+       int skip = 4;
+
+       //      if(GraphTraceLen < 1000) return;        // THIS CHECKS FOR A BUFFER TO SMALL
+
+       // First, correlate for SOF
+       for(i = 0; i < 100; i++) {
+               int corr = 0;
+               for(j = 0; j < arraylen(FrameSOF); j += skip) {
+                       corr += FrameSOF[j]*dest[i+(j/skip)];
+               }
+               if(corr > max) {
+                       max = corr;
+                       maxPos = i;
+               }
+       }
+       //      DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip));
+
+       int k = 0; // this will be our return value
+
+       // greg - If correlation is less than 1 then there's little point in continuing
+       if ((max/(arraylen(FrameSOF)/skip)) >= 1)
+       {
+
+               i = maxPos + arraylen(FrameSOF)/skip;
+       
+               uint8_t outBuf[20];
+               memset(outBuf, 0, sizeof(outBuf));
+               uint8_t mask = 0x01;
+               for(;;) {
+                       int corr0 = 0, corr1 = 0, corrEOF = 0;
+                       for(j = 0; j < arraylen(Logic0); j += skip) {
+                               corr0 += Logic0[j]*dest[i+(j/skip)];
+                       }
+                       for(j = 0; j < arraylen(Logic1); j += skip) {
+                               corr1 += Logic1[j]*dest[i+(j/skip)];
+                       }
+                       for(j = 0; j < arraylen(FrameEOF); j += skip) {
+                               corrEOF += FrameEOF[j]*dest[i+(j/skip)];
+                       }
+                       // Even things out by the length of the target waveform.
+                       corr0 *= 4;
+                       corr1 *= 4;
+       
+                       if(corrEOF > corr1 && corrEOF > corr0) {
+       //                      DbpString("EOF at %d", i);
+                               break;
+                       } else if(corr1 > corr0) {
+                               i += arraylen(Logic1)/skip;
+                               outBuf[k] |= mask;
+                       } else {
+                               i += arraylen(Logic0)/skip;
+                       }
+                       mask <<= 1;
+                       if(mask == 0) {
+                               k++;
+                               mask = 0x01;
+                       }
+                       if((i+(int)arraylen(FrameEOF)) >= 2000) {
+                               DbpString("ran off end!");
+                               break;
+                       }
+               }
+               if(mask != 0x01) { // this happens, when we miss the EOF
+                       // TODO: for some reason this happens quite often
+                       if (DEBUG) Dbprintf("error, uneven octet! (extra bits!) mask=%02x", mask);
+                       if (mask<0x08) k--; // discard the last uneven octet;
+                       // 0x08 is an assumption - but works quite often
+               }
+       //      uint8_t str1 [8];
+       //      itoa(k,str1);
+       //      strncat(str1," octets read",8);
+       
+       //      DbpString(  str1);    // DbpString("%d octets", k);
+       
+       //      for(i = 0; i < k; i+=3) {
+       //              //DbpString("# %2d: %02x ", i, outBuf[i]);
+       //              DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);
+       //      }
+       
+               for(i = 0; i < k; i++) {
+                       receivedResponse[i] = outBuf[i];
+               }
+       } // "end if correlation > 0"   (max/(arraylen(FrameSOF)/skip))
+       return k; // return the number of bytes demodulated
+
+///    DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));
+
+}
+
+
+// Now the GetISO15693 message from sniffing command
+static int GetIso15693AnswerFromSniff(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed)
+{
+       int c = 0;
+       uint8_t *dest = BigBuf_get_addr();
+       int getNext = 0;
+
+       int8_t prev = 0;
+
+// NOW READ RESPONSE
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+       //spindelay(60);        // greg - experiment to get rid of some of the 0 byte/failed reads
+       c = 0;
+       getNext = FALSE;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x43;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       int8_t b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       // The samples are correlations against I and Q versions of the
+                       // tone that the tag AM-modulates, so every other sample is I,
+                       // every other is Q. We just want power, so abs(I) + abs(Q) is
+                       // close to what we want.
+                       if(getNext) {
+                               int8_t r = ABS(b) + ABS(prev);
+
+                               dest[c++] = (uint8_t)r;
+
+                               if(c >= 20000) {
+                                       break;
+                               }
+                       } else {
+                               prev = b;
+                       }
+
+                       getNext = !getNext;
+               }
+       }
+
+       //////////////////////////////////////////
+       /////////// DEMODULATE ///////////////////
+       //////////////////////////////////////////
+
+       int i, j;
+       int max = 0, maxPos=0;
+
+       int skip = 4;
+
+//     if(GraphTraceLen < 1000) return;        // THIS CHECKS FOR A BUFFER TO SMALL
+
+       // First, correlate for SOF
+       for(i = 0; i < 19000; i++) {
+               int corr = 0;
+               for(j = 0; j < arraylen(FrameSOF); j += skip) {
+                       corr += FrameSOF[j]*dest[i+(j/skip)];
+               }
+               if(corr > max) {
+                       max = corr;
+                       maxPos = i;
+               }
+       }
+//     DbpString("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip));
+
+       int k = 0; // this will be our return value
+
+       // greg - If correlation is less than 1 then there's little point in continuing
+       if ((max/(arraylen(FrameSOF)/skip)) >= 1)       // THIS SHOULD BE 1
+       {
+       
+               i = maxPos + arraylen(FrameSOF)/skip;
+       
+               uint8_t outBuf[20];
+               memset(outBuf, 0, sizeof(outBuf));
+               uint8_t mask = 0x01;
+               for(;;) {
+                       int corr0 = 0, corr1 = 0, corrEOF = 0;
+                       for(j = 0; j < arraylen(Logic0); j += skip) {
+                               corr0 += Logic0[j]*dest[i+(j/skip)];
+                       }
+                       for(j = 0; j < arraylen(Logic1); j += skip) {
+                               corr1 += Logic1[j]*dest[i+(j/skip)];
+                       }
+                       for(j = 0; j < arraylen(FrameEOF); j += skip) {
+                               corrEOF += FrameEOF[j]*dest[i+(j/skip)];
+                       }
+                       // Even things out by the length of the target waveform.
+                       corr0 *= 4;
+                       corr1 *= 4;
+       
+                       if(corrEOF > corr1 && corrEOF > corr0) {
+       //                      DbpString("EOF at %d", i);
+                               break;
+                       } else if(corr1 > corr0) {
+                               i += arraylen(Logic1)/skip;
+                               outBuf[k] |= mask;
+                       } else {
+                               i += arraylen(Logic0)/skip;
+                       }
+                       mask <<= 1;
+                       if(mask == 0) {
+                               k++;
+                               mask = 0x01;
+                       }
+                       if((i+(int)arraylen(FrameEOF)) >= 2000) {
+                               DbpString("ran off end!");
+                               break;
+                       }
+               }
+               if(mask != 0x01) {
+                       DbpString("sniff: error, uneven octet! (discard extra bits!)");
+       ///             DbpString("   mask=%02x", mask);
+               }
+       //      uint8_t str1 [8];
+       //      itoa(k,str1);
+       //      strncat(str1," octets read",8);
+       
+       //      DbpString(  str1);    // DbpString("%d octets", k);
+       
+       //      for(i = 0; i < k; i+=3) {
+       //              //DbpString("# %2d: %02x ", i, outBuf[i]);
+       //              DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);
+       //      }
+       
+               for(i = 0; i < k; i++) {
+                       receivedResponse[i] = outBuf[i];
+               }
+       } // "end if correlation > 0"   (max/(arraylen(FrameSOF)/skip))
+       return k; // return the number of bytes demodulated
+
+///    DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));
+}
+
+
+static void BuildIdentifyRequest(void);
+//-----------------------------------------------------------------------------
+// Start to read an ISO 15693 tag. We send an identify request, then wait
+// for the response. The response is not demodulated, just left in the buffer
+// so that it can be downloaded to a PC and processed there.
+//-----------------------------------------------------------------------------
+void AcquireRawAdcSamplesIso15693(void)
+{
+       uint8_t *dest = BigBuf_get_addr();
+
+       int c = 0;
+       int getNext = 0;
+       int8_t prev = 0;
+
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       BuildIdentifyRequest();
+
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+       // Give the tags time to energize
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+       SpinDelay(100);
+
+       // Now send the command
+       FpgaSetupSsc();
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);
+
+       c = 0;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = ToSend[c];
+                       c++;
+                       if(c == ToSendMax+3) {
+                               break;
+                       }
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+                       (void)r;
+               }
+               WDT_HIT();
+       }
+
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+
+       c = 0;
+       getNext = FALSE;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x43;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       int8_t b;
+                       b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       // The samples are correlations against I and Q versions of the
+                       // tone that the tag AM-modulates, so every other sample is I,
+                       // every other is Q. We just want power, so abs(I) + abs(Q) is
+                       // close to what we want.
+                       if(getNext) {
+                               int8_t r = ABS(b) + ABS(prev);
+
+                               dest[c++] = (uint8_t)r;
+
+                               if(c >= 2000) {
+                                       break;
+                               }
+                       } else {
+                               prev = b;
+                       }
+
+                       getNext = !getNext;
+               }
+       }
+}
+
+
+void RecordRawAdcSamplesIso15693(void)
+{
+       uint8_t *dest = BigBuf_get_addr();
+
+       int c = 0;
+       int getNext = 0;
+       int8_t prev = 0;
+
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       // Setup SSC
+       FpgaSetupSsc();
+
+       // Start from off (no field generated)
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       SpinDelay(200);
+
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+       SpinDelay(100);
+
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+
+       c = 0;
+       getNext = FALSE;
+       for(;;) {
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+                       AT91C_BASE_SSC->SSC_THR = 0x43;
+               }
+               if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+                       int8_t b;
+                       b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+
+                       // The samples are correlations against I and Q versions of the
+                       // tone that the tag AM-modulates, so every other sample is I,
+                       // every other is Q. We just want power, so abs(I) + abs(Q) is
+                       // close to what we want.
+                       if(getNext) {
+                               int8_t r = ABS(b) + ABS(prev);
+
+                               dest[c++] = (uint8_t)r;
+
+                               if(c >= 7000) {
+                                       break;
+                               }
+                       } else {
+                               prev = b;
+                       }
+
+                       getNext = !getNext;
+                       WDT_HIT();
+               }
+       }
+       Dbprintf("fin record");
+}
+
+
+// Initialize the proxmark as iso15k reader 
+// (this might produces glitches that confuse some tags
+void Iso15693InitReader() {
+       LED_A_ON();
+       LED_B_ON();
+       LED_C_OFF();
+       LED_D_OFF();
+       
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       // Setup SSC
+       // FpgaSetupSsc();
+
+       // Start from off (no field generated)
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       SpinDelay(10);
+
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+       FpgaSetupSsc();
+
+       // Give the tags time to energize
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+       SpinDelay(250);
+
+       LED_A_ON();
+       LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+}
+
+///////////////////////////////////////////////////////////////////////
+// ISO 15693 Part 3 - Air Interface
+// This section basicly contains transmission and receiving of bits
+///////////////////////////////////////////////////////////////////////
+
+// Encode (into the ToSend buffers) an identify request, which is the first
+// thing that you must send to a tag to get a response.
+static void BuildIdentifyRequest(void)
+{
+       uint8_t cmd[5];
+
+       uint16_t crc;
+       // one sub-carrier, inventory, 1 slot, fast rate
+       // AFI is at bit 5 (1<<4) when doing an INVENTORY
+       cmd[0] = (1 << 2) | (1 << 5) | (1 << 1);
+       // inventory command code
+       cmd[1] = 0x01;
+       // no mask
+       cmd[2] = 0x00;
+       //Now the CRC
+       crc = Crc(cmd, 3);
+       cmd[3] = crc & 0xff;
+       cmd[4] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+// uid is in transmission order (which is reverse of display order)
+static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber )
+{
+       uint8_t cmd[13];
+
+       uint16_t crc;
+       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block
+       // followed by teh block data
+       // one sub-carrier, inventory, 1 slot, fast rate
+       cmd[0] = (1 << 6)| (1 << 5) | (1 << 1); // no SELECT bit, ADDR bit, OPTION bit
+       // READ BLOCK command code
+       cmd[1] = 0x20;
+       // UID may be optionally specified here
+       // 64-bit UID
+       cmd[2] = uid[0];
+       cmd[3] = uid[1];
+       cmd[4] = uid[2];
+       cmd[5] = uid[3];
+       cmd[6] = uid[4];
+       cmd[7] = uid[5];
+       cmd[8] = uid[6];
+       cmd[9] = uid[7]; // 0xe0; // always e0 (not exactly unique)
+       // Block number to read
+       cmd[10] = blockNumber;//0x00;
+       //Now the CRC
+       crc = Crc(cmd, 11); // the crc needs to be calculated over 12 bytes
+       cmd[11] = crc & 0xff;
+       cmd[12] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+// Now the VICC>VCD responses when we are simulating a tag
+ static void BuildInventoryResponse( uint8_t *uid)
+{
+       uint8_t cmd[12];
+
+       uint16_t crc;
+       // one sub-carrier, inventory, 1 slot, fast rate
+       // AFI is at bit 5 (1<<4) when doing an INVENTORY
+    //(1 << 2) | (1 << 5) | (1 << 1);
+       cmd[0] = 0; // 
+       cmd[1] = 0; // DSFID (data storage format identifier).  0x00 = not supported
+       // 64-bit UID
+       cmd[2] = uid[7]; //0x32;
+       cmd[3] = uid[6]; //0x4b;
+       cmd[4] = uid[5]; //0x03;
+       cmd[5] = uid[4]; //0x01;
+       cmd[6] = uid[3]; //0x00;
+       cmd[7] = uid[2]; //0x10;
+       cmd[8] = uid[1]; //0x05;
+       cmd[9] = uid[0]; //0xe0;
+       //Now the CRC
+       crc = Crc(cmd, 10);
+       cmd[10] = crc & 0xff;
+       cmd[11] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+// Universal Method for sending to and recv bytes from a tag
+//     init ... should we initialize the reader?
+//     speed ... 0 low speed, 1 hi speed 
+//     **recv will return you a pointer to the received data
+//     If you do not need the answer use NULL for *recv[] 
+//     return: lenght of received data
+int SendDataTag(uint8_t *send, int sendlen, int init, int speed, uint8_t **recv) {
+
+       int samples = 0;
+       int tsamples = 0;
+       int wait = 0;
+       int elapsed = 0;
+       
+       LED_A_ON();
+       LED_B_ON();
+       LED_C_OFF();
+       LED_D_OFF();
+       
+       if (init) Iso15693InitReader();
+
+       int answerLen=0;
+       uint8_t *answer = BigBuf_get_addr() + 3660;
+       if (recv != NULL) memset(answer, 0, 100);
+
+       if (!speed) {
+               // low speed (1 out of 256)
+               CodeIso15693AsReader256(send, sendlen);
+       } else {
+               // high speed (1 out of 4)
+               CodeIso15693AsReader(send, sendlen);
+       }
+       
+       LED_A_ON();
+       LED_B_OFF();
+       
+       TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  
+       // Now wait for a response
+       if (recv!=NULL) {
+               LED_A_OFF();
+               LED_B_ON();
+               answerLen = GetIso15693AnswerFromTag(answer, 100, &samples, &elapsed) ; 
+               *recv=answer;
+       }
+
+       LED_A_OFF();
+       LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+       
+       return answerLen;
+}
+
+
+// --------------------------------------------------------------------
+// Debug Functions 
+// --------------------------------------------------------------------
+
+// Decodes a message from a tag and displays its metadata and content
+#define DBD15STATLEN 48
+void DbdecodeIso15693Answer(int len, uint8_t *d) {
+       char status[DBD15STATLEN+1]={0};
+       uint16_t crc;
+
+       if (len>3) {
+               if (d[0]&(1<<3)) 
+                       strncat(status,"ProtExt ",DBD15STATLEN);
+               if (d[0]&1) { 
+                       // error
+                       strncat(status,"Error ",DBD15STATLEN);
+                       switch (d[1]) {
+                               case 0x01: 
+                                       strncat(status,"01:notSupp",DBD15STATLEN);
+                                       break;
+                               case 0x02: 
+                                       strncat(status,"02:notRecog",DBD15STATLEN);
+                                       break;
+                               case 0x03: 
+                                       strncat(status,"03:optNotSupp",DBD15STATLEN);
+                                       break;
+                               case 0x0f: 
+                                       strncat(status,"0f:noInfo",DBD15STATLEN);
+                                       break;
+                               case 0x10: 
+                                       strncat(status,"10:dontExist",DBD15STATLEN);
+                                       break;
+                               case 0x11: 
+                                       strncat(status,"11:lockAgain",DBD15STATLEN);
+                                       break;
+                               case 0x12: 
+                                       strncat(status,"12:locked",DBD15STATLEN);
+                                       break;
+                               case 0x13: 
+                                       strncat(status,"13:progErr",DBD15STATLEN);
+                                       break;
+                               case 0x14: 
+                                       strncat(status,"14:lockErr",DBD15STATLEN);
+                                       break;
+                               default:
+                                       strncat(status,"unknownErr",DBD15STATLEN);
+                       }
+                       strncat(status," ",DBD15STATLEN);
+               } else {
+                       strncat(status,"NoErr ",DBD15STATLEN);
+               }
+                       
+               crc=Crc(d,len-2);
+               if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) ) 
+                       strncat(status,"CrcOK",DBD15STATLEN);
+               else
+                       strncat(status,"CrcFail!",DBD15STATLEN); 
+
+               Dbprintf("%s",status);
+       }
+}
+
+
+
+///////////////////////////////////////////////////////////////////////
+// Functions called via USB/Client
+///////////////////////////////////////////////////////////////////////
+
+void SetDebugIso15693(uint32_t debug) {
+       DEBUG=debug;
+       Dbprintf("Iso15693 Debug is now %s",DEBUG?"on":"off");
+       return;
+}
+
+
+
+//-----------------------------------------------------------------------------
+// Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector
+// all demodulation performed in arm rather than host. - greg
+//-----------------------------------------------------------------------------
+void ReaderIso15693(uint32_t parameter)
+{
+       LED_A_ON();
+       LED_B_ON();
+       LED_C_OFF();
+       LED_D_OFF();
+
+       int answerLen1 = 0;
+       int answerLen2 = 0;
+       int answerLen3 = 0;
+       int i = 0;
+       int samples = 0;
+       int tsamples = 0;
+       int wait = 0;
+       int elapsed = 0;
+       uint8_t TagUID[8] = {0x00};
+
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
+       uint8_t *answer1 = BigBuf_get_addr() + 3660;
+       uint8_t *answer2 = BigBuf_get_addr() + 3760;
+       uint8_t *answer3 = BigBuf_get_addr() + 3860;
+       // Blank arrays
+       memset(answer1, 0x00, 300);
+
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+       // Setup SSC
+       FpgaSetupSsc();
+
+       // Start from off (no field generated)
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       SpinDelay(200);
+
+       // Give the tags time to energize
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+       SpinDelay(200);
+
+       LED_A_ON();
+       LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+
+       // FIRST WE RUN AN INVENTORY TO GET THE TAG UID
+       // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME
+
+       // Now send the IDENTIFY command
+       BuildIdentifyRequest();
+       
+       TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);
+       
+       // Now wait for a response
+       answerLen1 = GetIso15693AnswerFromTag(answer1, 100, &samples, &elapsed) ;
+
+       if (answerLen1 >=12) // we should do a better check than this
+       {
+               TagUID[0] = answer1[2];
+               TagUID[1] = answer1[3];
+               TagUID[2] = answer1[4];
+               TagUID[3] = answer1[5];
+               TagUID[4] = answer1[6];
+               TagUID[5] = answer1[7];
+               TagUID[6] = answer1[8]; // IC Manufacturer code
+               TagUID[7] = answer1[9]; // always E0
+
+       }
+
+       Dbprintf("%d octets read from IDENTIFY request:", answerLen1);
+       DbdecodeIso15693Answer(answerLen1,answer1);
+       Dbhexdump(answerLen1,answer1,true);
+
+       // UID is reverse
+       if (answerLen1>=12) 
+               Dbprintf("UID = %02hX%02hX%02hX%02hX%02hX%02hX%02hX%02hX",
+                       TagUID[7],TagUID[6],TagUID[5],TagUID[4],
+                       TagUID[3],TagUID[2],TagUID[1],TagUID[0]);
+
+
+       Dbprintf("%d octets read from SELECT request:", answerLen2);
+       DbdecodeIso15693Answer(answerLen2,answer2);
+       Dbhexdump(answerLen2,answer2,true);
+
+       Dbprintf("%d octets read from XXX request:", answerLen3);
+       DbdecodeIso15693Answer(answerLen3,answer3);
+       Dbhexdump(answerLen3,answer3,true);
+
+       // read all pages
+       if (answerLen1>=12 && DEBUG) {
+               i=0;                    
+               while (i<32) {  // sanity check, assume max 32 pages
+                       BuildReadBlockRequest(TagUID,i);
+             TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);  
+         answerLen2 = GetIso15693AnswerFromTag(answer2, 100, &samples, &elapsed);
+                       if (answerLen2>0) {
+                               Dbprintf("READ SINGLE BLOCK %d returned %d octets:",i,answerLen2);
+                               DbdecodeIso15693Answer(answerLen2,answer2);
+                               Dbhexdump(answerLen2,answer2,true);
+                               if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr 
+                       } 
+                       i++;
+               } 
+       }
+
+       LED_A_OFF();
+       LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+}
+
+// Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands
+// all demodulation performed in arm rather than host. - greg
+void SimTagIso15693(uint32_t parameter, uint8_t *uid)
+{
+       LED_A_ON();
+       LED_B_ON();
+       LED_C_OFF();
+       LED_D_OFF();
+
+       int answerLen1 = 0;
+       int samples = 0;
+       int tsamples = 0;
+       int wait = 0;
+       int elapsed = 0;
+
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
+       uint8_t *buf = BigBuf_get_addr() + 3660;
+       memset(buf, 0x00, 100);
+       
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+       FpgaSetupSsc();
+
+       // Start from off (no field generated)
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       SpinDelay(200);
+
+       LED_A_OFF();
+       LED_B_OFF();
+       LED_C_ON();
+       LED_D_OFF();
+
+       // Listen to reader
+       answerLen1 = GetIso15693AnswerFromSniff(buf, 100, &samples, &elapsed) ;
+
+       if (answerLen1 >=1) // we should do a better check than this
+       {
+               // Build a suitable reponse to the reader INVENTORY cocmmand
+               // not so obsvious, but in the call to BuildInventoryResponse,  the command is copied to the global ToSend buffer used below.
+               
+               BuildInventoryResponse(uid);
+       
+               TransmitTo15693Reader(ToSend,ToSendMax, &tsamples, &wait);
+       }
+
+       Dbprintf("%d octets read from reader command: %x %x %x %x %x %x %x %x %x", answerLen1,
+               buf[0], buf[1], buf[2], buf[3],
+               buf[4], buf[5], buf[6], buf[7], buf[8]);
+
+       Dbprintf("Simulationg uid: %x %x %x %x %x %x %x %x",
+               uid[0], uid[1], uid[2], uid[3],
+               uid[4], uid[5], uid[6], uid[7]);
+
+       LED_A_OFF();
+       LED_B_OFF();
+       LED_C_OFF();
+       LED_D_OFF();
+}
+
+
+// Since there is no standardized way of reading the AFI out of a tag, we will brute force it
+// (some manufactures offer a way to read the AFI, though)
+void BruteforceIso15693Afi(uint32_t speed) 
+{      
+       uint8_t data[20];
+       uint8_t *recv=data;
+       int datalen=0, recvlen=0;
+               
+       Iso15693InitReader();
+       
+       // first without AFI
+       // Tags should respond wihtout AFI and with AFI=0 even when AFI is active
+       
+       data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH | 
+               ISO15_REQ_INVENTORY | ISO15_REQINV_SLOT1;
+       data[1]=ISO15_CMD_INVENTORY;
+       data[2]=0; // mask length
+       datalen=AddCrc(data,3);
+       recvlen=SendDataTag(data,datalen,0,speed,&recv);
+       WDT_HIT();
+       if (recvlen>=12) {
+               Dbprintf("NoAFI UID=%s",sprintUID(NULL,&recv[2]));
+       }
+       
+       // now with AFI
+       
+       data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH | 
+               ISO15_REQ_INVENTORY | ISO15_REQINV_AFI | ISO15_REQINV_SLOT1;
+       data[1]=ISO15_CMD_INVENTORY;
+       data[2]=0; // AFI
+       data[3]=0; // mask length
+       
+       for (int i=0;i<256;i++) {
+               data[2]=i & 0xFF;
+               datalen=AddCrc(data,4);
+               recvlen=SendDataTag(data,datalen,0,speed,&recv);
+               WDT_HIT();
+               if (recvlen>=12) {
+                       Dbprintf("AFI=%i UID=%s",i,sprintUID(NULL,&recv[2]));
+               }
+       }       
+       Dbprintf("AFI Bruteforcing done.");
+       
+}
+
+// Allows to directly send commands to the tag via the client
+void DirectTag15693Command(uint32_t datalen,uint32_t speed, uint32_t recv, uint8_t data[]) {
+
+       int recvlen=0;
+       uint8_t *recvbuf = BigBuf_get_addr();
+//     UsbCommand n;
+       
+       if (DEBUG) {
+               Dbprintf("SEND");
+               Dbhexdump(datalen,data,true);
+       }
+       
+       recvlen=SendDataTag(data,datalen,1,speed,(recv?&recvbuf:NULL));
+
+       if (recv) { 
+               LED_B_ON();
+    cmd_send(CMD_ACK,recvlen>48?48:recvlen,0,0,recvbuf,48);
+               LED_B_OFF();    
+               
+               if (DEBUG) {
+                       Dbprintf("RECV");
+                       DbdecodeIso15693Answer(recvlen,recvbuf); 
+                       Dbhexdump(recvlen,recvbuf,true);
+               }
+       }
+
+}
+
+
+
+
+// --------------------------------------------------------------------
+// -- Misc & deprecated functions
+// --------------------------------------------------------------------
+
+/*
+
+// do not use; has a fix UID
+static void __attribute__((unused)) BuildSysInfoRequest(uint8_t *uid)
+{
+       uint8_t cmd[12];
+
+       uint16_t crc;
+       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block
+       // followed by teh block data
+       // one sub-carrier, inventory, 1 slot, fast rate
+       cmd[0] =  (1 << 5) | (1 << 1); // no SELECT bit
+       // System Information command code
+       cmd[1] = 0x2B;
+       // UID may be optionally specified here
+       // 64-bit UID
+       cmd[2] = 0x32;
+       cmd[3]= 0x4b;
+       cmd[4] = 0x03;
+       cmd[5] = 0x01;
+       cmd[6] = 0x00;
+       cmd[7] = 0x10;
+       cmd[8] = 0x05;
+       cmd[9]= 0xe0; // always e0 (not exactly unique)
+       //Now the CRC
+       crc = Crc(cmd, 10); // the crc needs to be calculated over 2 bytes
+       cmd[10] = crc & 0xff;
+       cmd[11] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+
+// do not use; has a fix UID
+static void __attribute__((unused)) BuildReadMultiBlockRequest(uint8_t *uid)
+{
+       uint8_t cmd[14];
+
+       uint16_t crc;
+       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block
+       // followed by teh block data
+       // one sub-carrier, inventory, 1 slot, fast rate
+       cmd[0] =  (1 << 5) | (1 << 1); // no SELECT bit
+       // READ Multi BLOCK command code
+       cmd[1] = 0x23;
+       // UID may be optionally specified here
+       // 64-bit UID
+       cmd[2] = 0x32;
+       cmd[3]= 0x4b;
+       cmd[4] = 0x03;
+       cmd[5] = 0x01;
+       cmd[6] = 0x00;
+       cmd[7] = 0x10;
+       cmd[8] = 0x05;
+       cmd[9]= 0xe0; // always e0 (not exactly unique)
+       // First Block number to read
+       cmd[10] = 0x00;
+       // Number of Blocks to read
+       cmd[11] = 0x2f; // read quite a few
+       //Now the CRC
+       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes
+       cmd[12] = crc & 0xff;
+       cmd[13] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+// do not use; has a fix UID
+static void __attribute__((unused)) BuildArbitraryRequest(uint8_t *uid,uint8_t CmdCode)
+{
+       uint8_t cmd[14];
+
+       uint16_t crc;
+       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block
+       // followed by teh block data
+       // one sub-carrier, inventory, 1 slot, fast rate
+       cmd[0] =   (1 << 5) | (1 << 1); // no SELECT bit
+       // READ BLOCK command code
+       cmd[1] = CmdCode;
+       // UID may be optionally specified here
+       // 64-bit UID
+       cmd[2] = 0x32;
+       cmd[3]= 0x4b;
+       cmd[4] = 0x03;
+       cmd[5] = 0x01;
+       cmd[6] = 0x00;
+       cmd[7] = 0x10;
+       cmd[8] = 0x05;
+       cmd[9]= 0xe0; // always e0 (not exactly unique)
+       // Parameter
+       cmd[10] = 0x00;
+       cmd[11] = 0x0a;
+
+//     cmd[12] = 0x00;
+//     cmd[13] = 0x00; //Now the CRC
+       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes
+       cmd[12] = crc & 0xff;
+       cmd[13] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+// do not use; has a fix UID
+static void __attribute__((unused)) BuildArbitraryCustomRequest(uint8_t uid[], uint8_t CmdCode)
+{
+       uint8_t cmd[14];
+
+       uint16_t crc;
+       // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block
+       // followed by teh block data
+       // one sub-carrier, inventory, 1 slot, fast rate
+       cmd[0] =   (1 << 5) | (1 << 1); // no SELECT bit
+       // READ BLOCK command code
+       cmd[1] = CmdCode;
+       // UID may be optionally specified here
+       // 64-bit UID
+       cmd[2] = 0x32;
+       cmd[3]= 0x4b;
+       cmd[4] = 0x03;
+       cmd[5] = 0x01;
+       cmd[6] = 0x00;
+       cmd[7] = 0x10;
+       cmd[8] = 0x05;
+       cmd[9]= 0xe0; // always e0 (not exactly unique)
+       // Parameter
+       cmd[10] = 0x05; // for custom codes this must be manufcturer code
+       cmd[11] = 0x00;
+
+//     cmd[12] = 0x00;
+//     cmd[13] = 0x00; //Now the CRC
+       crc = Crc(cmd, 12); // the crc needs to be calculated over 2 bytes
+       cmd[12] = crc & 0xff;
+       cmd[13] = crc >> 8;
+
+       CodeIso15693AsReader(cmd, sizeof(cmd));
+}
+
+
+
+
+*/
+
+
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