-
- int metric = 0;
-
- int parityBits = *((uint32_t *)(got+i+4));
- // 4 bytes of additional information...
- // maximum of 32 additional parity bit information
- //
- // TODO:
- // at each quarter bit period we can send power level (16 levels)
- // or each half bit period in 256 levels.
-
-
- int len = got[i+8];
-
- if (len > 100) {
- break;
- }
- if (i + len >= 1900) {
- break;
- }
-
- uint8_t *frame = (got+i+9);
-
- // Break and stick with current result if buffer was not completely full
- if (frame[0] == 0x44 && frame[1] == 0x44 && frame[3] == 0x44) { break; }
-
- char line[1000] = "";
- int j;
- for (j = 0; j < len; j++) {
- int oddparity = 0x01;
- int k;
-
- for (k=0;k<8;k++) {
- oddparity ^= (((frame[j] & 0xFF) >> k) & 0x01);
- }
-
- //if((parityBits >> (len - j - 1)) & 0x01) {
- if (isResponse && (oddparity != ((parityBits >> (len - j - 1)) & 0x01))) {
- sprintf(line+(j*4), "%02x! ", frame[j]);
- }
- else {
- sprintf(line+(j*4), "%02x ", frame[j]);
- }
- }
-
- char *crc;
- crc = "";
- if (len > 2) {
- uint8_t b1, b2;
- for (j = 0; j < (len - 1); j++) {
- // gives problems... search for the reason..
- /*if(frame[j] == 0xAA) {
- switch(frame[j+1]) {
- case 0x01:
- crc = "[1] Two drops close after each other";
- break;
- case 0x02:
- crc = "[2] Potential SOC with a drop in second half of bitperiod";
- break;
- case 0x03:
- crc = "[3] Segment Z after segment X is not possible";
- break;
- case 0x04:
- crc = "[4] Parity bit of a fully received byte was wrong";
- break;
- default:
- crc = "[?] Unknown error";
- break;
- }
- break;
- }*/
- }
-
- if (strlen(crc)==0) {
- if(!isResponse && len == 4) {
- // Rough guess that this is a command from the reader
- // For iClass the command byte is not part of the CRC
- ComputeCrc14443(CRC_ICLASS, &frame[1], len-3, &b1, &b2);
- }
- else {
- // For other data.. CRC might not be applicable (UPDATE commands etc.)
- ComputeCrc14443(CRC_ICLASS, frame, len-2, &b1, &b2);