X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/fac69c3d76b04088c337365ee124f8db4c13a2f0..571324a5c4b3edf7460633ca66ca5081aa4fdc6b:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index f5fee22a..3f597a1f 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -218,8 +218,8 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_ uint8_t FmtLen = 10; // sets of 4 bits = end data *startIdx = 0; errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); - if (errChk == 0 || *size < 64) return 0; - if (*size == 110) FmtLen = 22; // 22 sets of 4 bits + if ( errChk == 0 || (*size != 64 && *size != 128) ) return 0; + if (*size == 128) FmtLen = 22; // 22 sets of 4 bits //skip last 4bit parity row for simplicity *size = removeParity(BitStream, *startIdx + sizeof(preamble), 5, 0, FmtLen * 5); @@ -1596,9 +1596,14 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) return errCnt; } +bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { + size_t ststart = 0, stend = 0; + return DetectST_ext(buffer, size, foundclock, &ststart, &stend); +} + //by marshmellow //attempt to identify a Sequence Terminator in ASK modulated raw wave -bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { +bool DetectST_ext(uint8_t buffer[], size_t *size, int *foundclock, size_t *ststart, size_t *stend) { size_t bufsize = *size; //need to loop through all samples and identify our clock, look for the ST pattern uint8_t fndClk[] = {8,16,32,40,50,64,128}; @@ -1751,7 +1756,7 @@ bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { size_t newloc = 0; i=0; if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen); - + bool firstrun = true; // warning - overwriting buffer given with raw wave data with ST removed... while ( dataloc < bufsize-(clk/2) ) { //compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part) @@ -1759,6 +1764,15 @@ bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { for(i=0; i < clk/2-tol; ++i) { buffer[dataloc+i] = high+5; } + } //test for single sample outlier (high between two lows) in the case of very strong waves + if (buffer[dataloc] >= high && buffer[dataloc+2] <= low) { + buffer[dataloc] = buffer[dataloc+2]; + buffer[dataloc+1] = buffer[dataloc+2]; + } + if (firstrun) { + *stend = dataloc; + *ststart = dataloc-(clk*4); + firstrun=false; } for (i=0; i