X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/3c6542087e2a0f92f5c1024b812aac969253a764..50282b85e45dba28ece1cc10ab3f063ebca8b4c8:/common/lfdemod.c?ds=inline diff --git a/common/lfdemod.c b/common/lfdemod.c index 2b1373ee..5fec933f 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -25,15 +25,13 @@ void dummy(char *fmt, ...){} #define prnt dummy #endif -uint8_t justNoise(uint8_t *BitStream, size_t size) -{ - static const uint8_t THRESHOLD = 123; - //test samples are not just noise - uint8_t justNoise1 = 1; - for(size_t idx=0; idx < size && justNoise1 ;idx++){ - justNoise1 = BitStream[idx] < THRESHOLD; - } - return justNoise1; +//test samples are not just noise +uint8_t justNoise(uint8_t *bits, size_t size) { + #define THRESHOLD 123 + uint8_t val = 1; + for(size_t idx=0; idx < size && val ;idx++) + val = bits[idx] < THRESHOLD; + return val; } //by marshmellow @@ -81,8 +79,8 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p j--; // overwrite parity with next data // if parity fails then return 0 switch (pType) { - case 3: if (BitStream[j]==1) { return 0 }; break; //should be 0 spacer bit - case 2: if (BitStream[j]==0) { return 0 }; break; //should be 1 spacer bit + case 3: if (BitStream[j]==1) { return 0; } break; //should be 0 spacer bit + case 2: if (BitStream[j]==0) { return 0; } break; //should be 1 spacer bit default: if (parityTest(parityWd, pLen, pType) == 0) { return 0; } break; //test parity } bitCnt+=(pLen-1); @@ -169,13 +167,13 @@ uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_ //by marshmellow //takes 1s and 0s and searches for EM410x format - output EM ID -uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) +int Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) { //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future // otherwise could be a void with no arguments //set defaults uint32_t i = 0; - if (BitStream[1]>1) return 0; //allow only 1s and 0s + if (BitStream[1]>1) return -1; //allow only 1s and 0s // 111111111 bit pattern represent start of frame // include 0 in front to help get start pos @@ -186,14 +184,15 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_ uint8_t FmtLen = 10; *startIdx = 0; errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); - if (errChk == 0 || *size < 64) return 0; + if (errChk == 0 ) return -4; + if (*size < 64) return -3; if (*size > 64) FmtLen = 22; *startIdx += 1; //get rid of 0 from preamble idx = *startIdx + 9; for (i=0; i> 63);