X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/936e0729f9a4d62452e422a87ea372edd39ef165..415274a7c3253b71b582c2f563bb54080c2790be:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 88a250d8..5d19c897 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -11,8 +11,6 @@ #include #include #include "lfdemod.h" - - uint8_t justNoise(uint8_t *BitStream, size_t size) { static const uint8_t THRESHOLD = 123; @@ -25,19 +23,19 @@ uint8_t justNoise(uint8_t *BitStream, size_t size) } //by marshmellow -//get high and low with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise +//get high and low values of a wave with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo) { *high=0; *low=255; // get high and low thresholds - for (int i=0; i < size; i++){ + for (size_t i=0; i < size; i++){ if (BitStream[i] > *high) *high = BitStream[i]; if (BitStream[i] < *low) *low = BitStream[i]; } if (*high < 123) return -1; // just noise - *high = (int)(((*high-128)*(((float)fuzzHi)/100))+128); - *low = (int)(((*low-128)*(((float)fuzzLo)/100))+128); + *high = ((*high-128)*fuzzHi + 12800)/100; + *low = ((*low-128)*fuzzLo + 12800)/100; return 1; } @@ -50,443 +48,340 @@ uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) for (uint8_t i = 0; i < bitLen; i++){ ans ^= ((bits >> i) & 1); } - //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); + //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); return (ans == pType); } //by marshmellow -//search for given preamble in given BitStream and return startIndex and length +//search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx) { - uint8_t foundCnt=0; - for (int idx=0; idx < *size - pLen; idx++){ - if (memcmp(BitStream+idx, preamble, pLen) == 0){ - //first index found - foundCnt++; - if (foundCnt == 1){ - *startIdx = idx; - } - if (foundCnt == 2){ - *size = idx - *startIdx; - return 1; - } - } - } - return 0; + uint8_t foundCnt=0; + for (int idx=0; idx < *size - pLen; idx++){ + if (memcmp(BitStream+idx, preamble, pLen) == 0){ + //first index found + foundCnt++; + if (foundCnt == 1){ + *startIdx = idx; + } + if (foundCnt == 2){ + *size = idx - *startIdx; + return 1; + } + } + } + return 0; } - //by marshmellow //takes 1s and 0s and searches for EM410x format - output EM ID -uint64_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx) +uint8_t 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 - uint64_t lo=0; - uint32_t i = 0; - if (BitStream[1]>1){ //allow only 1s and 0s - // PrintAndLog("no data found"); - return 0; - } - // 111111111 bit pattern represent start of frame - uint8_t preamble[] = {1,1,1,1,1,1,1,1,1}; - uint32_t idx = 0; - uint32_t parityBits = 0; - uint8_t errChk = 0; - *startIdx = 0; - for (uint8_t extraBitChk=0; extraBitChk<5; extraBitChk++){ - errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx); - if (errChk == 0) return 0; - idx = *startIdx + 9; - for (i=0; i<10;i++){ //loop through 10 sets of 5 bits (50-10p = 40 bits) - parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5); - //check even parity - if (parityTest(parityBits, 5, 0) == 0){ - //parity failed try next bit (in the case of 1111111111) but last 9 = preamble - startIdx++; - errChk = 0; - break; - } - for (uint8_t ii=0; ii<4; ii++){ - lo = (lo << 1LL) | (BitStream[(i*5)+ii+idx]); - } - } - if (errChk != 0) return lo; - //skip last 5 bit parity test for simplicity. - // *size = 64; - } - return 0; + //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 + + // 111111111 bit pattern represent start of frame + // include 0 in front to help get start pos + uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1}; + uint32_t idx = 0; + uint32_t parityBits = 0; + uint8_t errChk = 0; + uint8_t FmtLen = 10; + *startIdx = 0; + errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); + if (errChk == 0 || *size < 64) return 0; + if (*size > 64) FmtLen = 22; + *startIdx += 1; //get rid of 0 from preamble + idx = *startIdx + 9; + for (i=0; i> 63); + *lo = (*lo << 1) | (BitStream[(i*5)+ii+idx]); + } + } + if (errChk != 0) return 1; + //skip last 5 bit parity test for simplicity. + // *size = 64 | 128; + return 0; } //by marshmellow -//takes 2 arguments - clock and invert both as integers -//attempts to demodulate ask while decoding manchester -//prints binary found and saves in graphbuffer for further commands -int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) +//demodulates strong heavily clipped samples +int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low) { - int i; - int clk2=*clk; - *clk=DetectASKClock(BinStream, *size, *clk); //clock default - - // if autodetected too low then adjust //MAY NEED ADJUSTMENT - if (clk2==0 && *clk<8) *clk =64; - if (clk2==0 && *clk<32) *clk=32; - if (*invert != 0 && *invert != 1) *invert=0; - uint32_t initLoopMax = 200; - if (initLoopMax > *size) initLoopMax=*size; - // Detect high and lows - // 25% fuzz in case highs and lows aren't clipped [marshmellow] - int high, low, ans; - ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); - if (ans<1) return -2; //just noise - - // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter - int tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - if (*clk<=32)tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - int iii = 0; - uint32_t gLen = *size; - if (gLen > 3000) gLen=3000; - uint8_t errCnt =0; - uint32_t bestStart = *size; - uint32_t bestErrCnt = (*size/1000); - uint32_t maxErr = (*size/1000); - // PrintAndLog("DEBUG - lastbit - %d",lastBit); - // loop to find first wave that works - for (iii=0; iii < gLen; ++iii){ - if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){ - lastBit=iii-*clk; - errCnt=0; - // loop through to see if this start location works - for (i = iii; i < *size; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ - lastBit+=*clk; - } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - + size_t bitCnt=0, smplCnt=0, errCnt=0; + uint8_t waveHigh = 0; + for (size_t i=0; i < *size; i++){ + if (BinStream[i] >= high && waveHigh){ + smplCnt++; + } else if (BinStream[i] <= low && !waveHigh){ + smplCnt++; + } else { //transition + if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){ + if (smplCnt > clk-(clk/4)-1) { //full clock + if (smplCnt > clk + (clk/4)+1) { //too many samples errCnt++; - lastBit+=*clk;//skip over until hit too many errors - if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over + BinStream[bitCnt++]=7; + } else if (waveHigh) { + BinStream[bitCnt++] = invert; + BinStream[bitCnt++] = invert; + } else if (!waveHigh) { + BinStream[bitCnt++] = invert ^ 1; + BinStream[bitCnt++] = invert ^ 1; } + waveHigh ^= 1; + smplCnt = 0; + } else if (smplCnt > (clk/2) - (clk/4)-1) { + if (waveHigh) { + BinStream[bitCnt++] = invert; + } else if (!waveHigh) { + BinStream[bitCnt++] = invert ^ 1; + } + waveHigh ^= 1; + smplCnt = 0; + } else if (!bitCnt) { + //first bit + waveHigh = (BinStream[i] >= high); + smplCnt = 1; + } else { + smplCnt++; + //transition bit oops } - if ((i-iii) >(400 * *clk)) break; //got plenty of bits - } - //we got more than 64 good bits and not all errors - if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt= high) && ((i-lastBit) > (*clk-tol))){ - lastBit += *clk; - BinStream[bitnum] = *invert; - bitnum++; - } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - BinStream[bitnum] = 1-*invert; - bitnum++; - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (bitnum > 0){ - BinStream[bitnum]=77; - bitnum++; - } + *size = bitCnt; + return errCnt; +} - lastBit+=*clk;//skip over error - } - } - if (bitnum >=400) break; - } - *size=bitnum; - } else{ - *invert=bestStart; - *clk=iii; - return -1; +//by marshmellow +void askAmp(uint8_t *BitStream, size_t size) +{ + for(size_t i = 1; i=30) //large jump up + BitStream[i]=127; + else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down + BitStream[i]=-127; } - return bestErrCnt; + return; } //by marshmellow -//encode binary data into binary manchester -int ManchesterEncode(uint8_t *BitStream, size_t size) +//attempts to demodulate ask modulations, askType == 0 for ask/raw, askType==1 for ask/manchester +int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp, uint8_t askType) { - size_t modIdx=20000, i=0; - if (size>modIdx) return -1; - for (size_t idx=0; idx < size; idx++){ - BitStream[idx+modIdx++] = BitStream[idx]; - BitStream[idx+modIdx++] = BitStream[idx]^1; - } - for (; i<(size*2); i++){ - BitStream[i] = BitStream[i+20000]; - } - return i; + if (*size==0) return -1; + int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default + if (*clk==0 || start < 0) return -3; + if (*invert != 1) *invert = 0; + if (amp==1) askAmp(BinStream, *size); + + uint8_t initLoopMax = 255; + if (initLoopMax > *size) initLoopMax = *size; + // Detect high and lows + //25% clip in case highs and lows aren't clipped [marshmellow] + int high, low; + if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) + return -2; //just noise + + size_t errCnt = 0; + // if clean clipped waves detected run alternate demod + if (DetectCleanAskWave(BinStream, *size, high, low)) { + errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); + if (askType) //askman + return manrawdecode(BinStream, size, 0); + else //askraw + return errCnt; + } + + int lastBit; //set first clock check - can go negative + size_t i, bitnum = 0; //output counter + uint8_t midBit = 0; + uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave + if (*clk <= 32) tol = 1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely + size_t MaxBits = 1024; + lastBit = start - *clk; + + for (i = start; i < *size; ++i) { + if (i-lastBit >= *clk-tol){ + if (BinStream[i] >= high) { + BinStream[bitnum++] = *invert; + } else if (BinStream[i] <= low) { + BinStream[bitnum++] = *invert ^ 1; + } else if (i-lastBit >= *clk+tol) { + if (bitnum > 0) { + BinStream[bitnum++]=7; + errCnt++; + } + } else { //in tolerance - looking for peak + continue; + } + midBit = 0; + lastBit += *clk; + } else if (i-lastBit >= (*clk/2-tol) && !midBit && !askType){ + if (BinStream[i] >= high) { + BinStream[bitnum++] = *invert; + } else if (BinStream[i] <= low) { + BinStream[bitnum++] = *invert ^ 1; + } else if (i-lastBit >= *clk/2+tol) { + BinStream[bitnum] = BinStream[bitnum-1]; + bitnum++; + } else { //in tolerance - looking for peak + continue; + } + midBit = 1; + } + if (bitnum >= MaxBits) break; + } + *size = bitnum; + return errCnt; } //by marshmellow //take 10 and 01 and manchester decode //run through 2 times and take least errCnt -int manrawdecode(uint8_t * BitStream, size_t *size) +int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert) { - int bitnum=0; - int errCnt =0; - int i=1; - int bestErr = 1000; - int bestRun = 0; - int ii=1; - for (ii=1;ii<3;++ii){ - i=1; - for (i=i+ii;i<*size-2;i+=2){ - if(BitStream[i]==1 && (BitStream[i+1]==0)){ - } else if((BitStream[i]==0)&& BitStream[i+1]==1){ - } else { + uint16_t bitnum=0, MaxBits = 512, errCnt = 0; + size_t i, ii; + uint16_t bestErr = 1000, bestRun = 0; + if (*size < 16) return -1; + //find correct start position [alignment] + for (ii=0;ii<2;++ii){ + for (i=ii; i<*size-3; i+=2) + if (BitStream[i]==BitStream[i+1]) errCnt++; - } - if(bitnum>300) break; - } + if (bestErr>errCnt){ bestErr=errCnt; bestRun=ii; } errCnt=0; } - errCnt=bestErr; - if (errCnt<20){ - ii=bestRun; - i=1; - for (i=i+ii;i < *size-2;i+=2){ - if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ - BitStream[bitnum++]=0; - } else if((BitStream[i] == 0) && BitStream[i+1] == 1){ - BitStream[bitnum++]=1; - } else { - BitStream[bitnum++]=77; - //errCnt++; - } - if(bitnum>300) break; + //decode + for (i=bestRun; i < *size-3; i+=2){ + if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ + BitStream[bitnum++]=invert; + } else if((BitStream[i] == 0) && BitStream[i+1] == 1){ + BitStream[bitnum++]=invert^1; + } else { + BitStream[bitnum++]=7; } - *size=bitnum; + if(bitnum>MaxBits) break; } - return errCnt; + *size=bitnum; + return bestErr; +} + +uint32_t manchesterEncode2Bytes(uint16_t datain) { + uint32_t output = 0; + uint8_t curBit = 0; + for (uint8_t i=0; i<16; i++) { + curBit = (datain >> (15-i) & 1); + output |= (1<<(((15-i)*2)+curBit)); + } + return output; +} + +//by marshmellow +//encode binary data into binary manchester +int ManchesterEncode(uint8_t *BitStream, size_t size) +{ + size_t modIdx=20000, i=0; + if (size>modIdx) return -1; + for (size_t idx=0; idx < size; idx++){ + BitStream[idx+modIdx++] = BitStream[idx]; + BitStream[idx+modIdx++] = BitStream[idx]^1; + } + for (; i<(size*2); i++){ + BitStream[i] = BitStream[i+20000]; + } + return i; } //by marshmellow -//take 01 or 10 = 0 and 11 or 00 = 1 +//take 01 or 10 = 1 and 11 or 00 = 0 +//check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010 +//decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) { - uint8_t bitnum=0; - uint32_t errCnt =0; - uint32_t i; - i=offset; - for (;i<*size-2; i+=2){ + uint16_t bitnum = 0; + uint16_t errCnt = 0; + size_t i = offset; + uint16_t MaxBits=512; + //if not enough samples - error + if (*size < 51) return -1; + //check for phase change faults - skip one sample if faulty + uint8_t offsetA = 1, offsetB = 1; + for (; i<48; i+=2){ + if (BitStream[i+1]==BitStream[i+2]) offsetA=0; + if (BitStream[i+2]==BitStream[i+3]) offsetB=0; + } + if (!offsetA && offsetB) offset++; + for (i=offset; i<*size-3; i+=2){ + //check for phase error + if (BitStream[i+1]==BitStream[i+2]) { + BitStream[bitnum++]=7; + errCnt++; + } if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){ BitStream[bitnum++]=1^invert; } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){ BitStream[bitnum++]=invert; } else { - BitStream[bitnum++]=77; + BitStream[bitnum++]=7; errCnt++; } - if(bitnum>250) break; + if(bitnum>MaxBits) break; } *size=bitnum; return errCnt; } -//by marshmellow -//takes 2 arguments - clock and invert both as integers -//attempts to demodulate ask only -//prints binary found and saves in graphbuffer for further commands -int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) +// by marshmellow +// demod gProxIIDemod +// error returns as -x +// success returns start position in BitStream +// BitStream must contain previously askrawdemod and biphasedemoded data +int gProxII_Demod(uint8_t BitStream[], size_t *size) { - uint32_t i; - // int invert=0; //invert default - int clk2 = *clk; - *clk=DetectASKClock(BinStream, *size, *clk); //clock default - //uint8_t BitStream[502] = {0}; - - //HACK: if clock not detected correctly - default - if (clk2==0 && *clk<8) *clk =64; - if (clk2==0 && *clk<32 && clk2==0) *clk=32; - if (*invert != 0 && *invert != 1) *invert =0; - uint32_t initLoopMax = 200; - if (initLoopMax > *size) initLoopMax=*size; - // Detect high and lows - //25% fuzz in case highs and lows aren't clipped [marshmellow] - int high, low, ans; - ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); - if (ans<1) return -2; //just noise - - //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter - uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock - // if they fall + or - this value + clock from last valid wave - if (*clk == 32) tol=1; //clock tolerance may not be needed anymore currently set to - // + or - 1 but could be increased for poor waves or removed entirely - uint32_t iii = 0; - uint32_t gLen = *size; - if (gLen > 500) gLen=500; - uint8_t errCnt =0; - uint32_t bestStart = *size; - uint32_t bestErrCnt = (*size/1000); - uint32_t maxErr = bestErrCnt; - uint8_t midBit=0; - //PrintAndLog("DEBUG - lastbit - %d",lastBit); - //loop to find first wave that works - for (iii=0; iii < gLen; ++iii){ - if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){ - lastBit=iii-*clk; - //loop through to see if this start location works - for (i = iii; i < *size; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit+=*clk; - midBit=0; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - midBit=0; - } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ - //no mid bar found - midBit=1; - } else { - //mid value found or no bar supposed to be here - - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - - errCnt++; - lastBit+=*clk;//skip over until hit too many errors - if (errCnt > ((*size/1000))){ //allow 1 error for every 1000 samples else start over - errCnt=0; - break; - } - } - } - if ((i-iii)>(500 * *clk)) break; //got enough bits - } - //we got more than 64 good bits and not all errors - if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<(*size/1000))) { - //possible good read - if (errCnt==0){ - bestStart=iii; - bestErrCnt=errCnt; - break; //great read - finish - } - if (errCnt= high) && ((i-lastBit) > (*clk-tol))){ - lastBit += *clk; - BinStream[bitnum] = *invert; - bitnum++; - midBit=0; - } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - BinStream[bitnum] = 1-*invert; - bitnum++; - midBit=0; - } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - BinStream[bitnum] = 1 - *invert; - bitnum++; - } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - BinStream[bitnum] = *invert; - bitnum++; - } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ - //no mid bar found - midBit=1; - if (bitnum!=0) BinStream[bitnum] = BinStream[bitnum-1]; - bitnum++; - - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (bitnum > 0){ - BinStream[bitnum]=77; - bitnum++; - } + size_t startIdx=0; + uint8_t preamble[] = {1,1,1,1,1,0}; - lastBit+=*clk;//skip over error - } - } - if (bitnum >=400) break; - } - *size=bitnum; - } else{ - *invert=bestStart; - *clk=iii; - return -1; + uint8_t errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found + if (*size != 96) return -2; //should have found 96 bits + //check first 6 spacer bits to verify format + if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){ + //confirmed proper separator bits found + //return start position + return (int) startIdx; } - return bestErrCnt; + return -5; } + //translate wave to 11111100000 (1 for each short wave 0 for each long wave) size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) { - uint32_t last_transition = 0; - uint32_t idx = 1; + size_t last_transition = 0; + size_t idx = 1; //uint32_t maxVal=0; if (fchigh==0) fchigh=10; if (fclow==0) fclow=8; //set the threshold close to 0 (graph) or 128 std to avoid static uint8_t threshold_value = 123; - + size_t preLastSample = 0; + size_t LastSample = 0; + size_t currSample = 0; // sync to first lo-hi transition, and threshold // Need to threshold first sample @@ -506,61 +401,76 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow // Check for 0->1 transition if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition - if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise + preLastSample = LastSample; + LastSample = currSample; + currSample = idx-last_transition; + if (currSample < (fclow-2)){ //0-5 = garbage noise //do nothing with extra garbage - } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves - dest[numBits]=1; - } else { //9+ = 10 waves - dest[numBits]=0; + } else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves + if (LastSample > (fchigh-2) && preLastSample < (fchigh-1)){ + dest[numBits-1]=1; //correct last 9 wave surrounded by 8 waves + } + dest[numBits++]=1; + + } else if (currSample > (fchigh+1) && !numBits) { //12 + and first bit = garbage + //do nothing with beginning garbage + } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's + dest[numBits++]=1; + } else { //9+ = 10 sample waves + dest[numBits++]=0; } last_transition = idx; - numBits++; } } return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0 } -uint32_t myround2(float f) -{ - if (f >= 2000) return 2000;//something bad happened - return (uint32_t) (f + (float)0.5); -} - //translate 11111100000 to 10 -size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, - uint8_t invert, uint8_t fchigh, uint8_t fclow) +size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, + uint8_t invert, uint8_t fchigh, uint8_t fclow) { uint8_t lastval=dest[0]; - uint32_t idx=0; + size_t idx=0; size_t numBits=0; uint32_t n=1; - for( idx=1; idx < size; idx++) { - - if (dest[idx]==lastval) { - n++; - continue; - } + n++; + if (dest[idx]==lastval) continue; + //if lastval was 1, we have a 1->0 crossing - if ( dest[idx-1]==1 ) { - n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); - } else {// 0->1 crossing - n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor + if (dest[idx-1]==1) { + if (!numBits && n < rfLen/fclow) { + n=0; + lastval = dest[idx]; + continue; + } + n = (n * fclow + rfLen/2) / rfLen; + } else {// 0->1 crossing + //test first bitsample too small + if (!numBits && n < rfLen/fchigh) { + n=0; + lastval = dest[idx]; + continue; + } + n = (n * fchigh + rfLen/2) / rfLen; } if (n == 0) n = 1; - if(n < maxConsequtiveBits) //Consecutive - { - if(invert==0){ //invert bits - memset(dest+numBits, dest[idx-1] , n); - }else{ - memset(dest+numBits, dest[idx-1]^1 , n); - } - numBits += n; - } + memset(dest+numBits, dest[idx-1]^invert , n); + numBits += n; n=0; lastval=dest[idx]; }//end for + // if valid extra bits at the end were all the same frequency - add them in + if (n > rfLen/fchigh) { + if (dest[idx-2]==1) { + n = (n * fclow + rfLen/2) / rfLen; + } else { + n = (n * fchigh + rfLen/2) / rfLen; + } + memset(dest+numBits, dest[idx-1]^invert , n); + numBits += n; + } return numBits; } //by marshmellow (from holiman's base) @@ -569,40 +479,40 @@ int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t { // FSK demodulator size = fsk_wave_demod(dest, size, fchigh, fclow); - size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow); + size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow); return size; } // loop to get raw HID waveform then FSK demodulate the TAG ID from it int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) { - if (justNoise(dest, *size)) return -1; - - size_t numStart=0, size2=*size, startIdx=0; - // FSK demodulator - *size = fskdemod(dest, size2,50,1,10,8); //fsk2a - if (*size < 96) return -2; - // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 - uint8_t preamble[] = {0,0,0,1,1,1,0,1}; - // find bitstring in array - uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); - if (errChk == 0) return -3; //preamble not found - - numStart = startIdx + sizeof(preamble); - // final loop, go over previously decoded FSK data and manchester decode into usable tag ID - for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ - if (dest[idx] == dest[idx+1]){ - return -4; //not manchester data - } - *hi2 = (*hi2<<1)|(*hi>>31); - *hi = (*hi<<1)|(*lo>>31); - //Then, shift in a 0 or one into low - if (dest[idx] && !dest[idx+1]) // 1 0 - *lo=(*lo<<1)|1; - else // 0 1 - *lo=(*lo<<1)|0; - } - return (int)startIdx; + if (justNoise(dest, *size)) return -1; + + size_t numStart=0, size2=*size, startIdx=0; + // FSK demodulator + *size = fskdemod(dest, size2,50,1,10,8); //fsk2a + if (*size < 96*2) return -2; + // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 + uint8_t preamble[] = {0,0,0,1,1,1,0,1}; + // find bitstring in array + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found + + numStart = startIdx + sizeof(preamble); + // final loop, go over previously decoded FSK data and manchester decode into usable tag ID + for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ + if (dest[idx] == dest[idx+1]){ + return -4; //not manchester data + } + *hi2 = (*hi2<<1)|(*hi>>31); + *hi = (*hi<<1)|(*lo>>31); + //Then, shift in a 0 or one into low + if (dest[idx] && !dest[idx+1]) // 1 0 + *lo=(*lo<<1)|1; + else // 0 1 + *lo=(*lo<<1)|0; + } + return (int)startIdx; } // loop to get raw paradox waveform then FSK demodulate the TAG ID from it @@ -637,7 +547,7 @@ int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, ui return (int)startIdx; } -uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) +uint32_t bytebits_to_byte(uint8_t *src, size_t numbits) { uint32_t num = 0; for(int i = 0 ; i < numbits ; i++) @@ -648,6 +558,17 @@ uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) return num; } +//least significant bit first +uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits) +{ + uint32_t num = 0; + for(int i = 0 ; i < numbits ; i++) + { + num = (num << 1) | *(src + (numbits-(i+1))); + } + return num; +} + int IOdemodFSK(uint8_t *dest, size_t size) { if (justNoise(dest, size)) return -1; @@ -676,11 +597,28 @@ int IOdemodFSK(uint8_t *dest, size_t size) return (int) startIdx; } return -5; +} + +// by marshmellow +// find viking preamble 0xF200 in already demoded data +int VikingDemod_AM(uint8_t *dest, size_t *size) { + if (justNoise(dest, *size)) return -1; + //make sure buffer has data + if (*size < 64*2) return -2; + + size_t startIdx = 0; + uint8_t preamble[] = {1,1,1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -4; //preamble not found + + if (*size != 64) return -5; + //return start position + return (int) startIdx; } // by marshmellow // takes a array of binary values, start position, length of bits per parity (includes parity bit), -// Parity Type (1 for odd 0 for even), and binary Length (length to run) +// Parity Type (1 for odd; 0 for even; 2 Always 1's), and binary Length (length to run) size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) { uint32_t parityWd = 0; @@ -688,11 +626,15 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p for (int word = 0; word < (bLen); word+=pLen){ for (int bit=0; bit < pLen; bit++){ parityWd = (parityWd << 1) | BitStream[startIdx+word+bit]; - BitStream[j++] = (BitStream[startIdx+word+bit]); + BitStream[j++] = (BitStream[startIdx+word+bit]); } - j--; + j--; // overwrite parity with next data // if parity fails then return 0 - if (parityTest(parityWd, pLen, pType) == 0) return -1; + if (pType == 2) { // then marker bit which should be a 1 + if (!BitStream[j]) return 0; + } else { + if (parityTest(parityWd, pLen, pType) == 0) return 0; + } bitCnt+=(pLen-1); parityWd = 0; } @@ -701,6 +643,21 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p return bitCnt; } +// Ask/Biphase Demod then try to locate an ISO 11784/85 ID +// BitStream must contain previously askrawdemod and biphasedemoded data +int FDXBdemodBI(uint8_t *dest, size_t *size) +{ + //make sure buffer has enough data + if (*size < 128) return -1; + + size_t startIdx = 0; + uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1}; + + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -2; //preamble not found + return (int)startIdx; +} + // by marshmellow // FSK Demod then try to locate an AWID ID int AWIDdemodFSK(uint8_t *dest, size_t *size) @@ -726,17 +683,17 @@ int AWIDdemodFSK(uint8_t *dest, size_t *size) // FSK Demod then try to locate an Farpointe Data (pyramid) ID int PyramiddemodFSK(uint8_t *dest, size_t *size) { - //make sure buffer has data - if (*size < 128*50) return -5; + //make sure buffer has data + if (*size < 128*50) return -5; - //test samples are not just noise - if (justNoise(dest, *size)) return -1; + //test samples are not just noise + if (justNoise(dest, *size)) return -1; - // FSK demodulator - *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 - if (*size < 128) return -2; //did we get a good demod? + // FSK demodulator + *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 + if (*size < 128) return -2; //did we get a good demod? - uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; + uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; size_t startIdx = 0; uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); if (errChk == 0) return -4; //preamble not found @@ -744,187 +701,336 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size) return (int)startIdx; } +// by marshmellow +// to detect a wave that has heavily clipped (clean) samples +uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low) +{ + uint16_t allPeaks=1; + uint16_t cntPeaks=0; + size_t loopEnd = 512+60; + if (loopEnd > size) loopEnd = size; + for (size_t i=60; ilow && dest[i] 300) return 1; + } + return allPeaks; +} + +// by marshmellow +// to help detect clocks on heavily clipped samples +// based on count of low to low +int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low) +{ + uint8_t fndClk[] = {8,16,32,40,50,64,128}; + size_t startwave; + size_t i = 0; + size_t minClk = 255; + // get to first full low to prime loop and skip incomplete first pulse + while ((dest[i] < high) && (i < size)) + ++i; + while ((dest[i] > low) && (i < size)) + ++i; + + // loop through all samples + while (i < size) { + // measure from low to low + while ((dest[i] > low) && (i < size)) + ++i; + startwave= i; + while ((dest[i] < high) && (i < size)) + ++i; + while ((dest[i] > low) && (i < size)) + ++i; + //get minimum measured distance + if (i-startwave < minClk && i < size) + minClk = i - startwave; + } + // set clock + for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { + if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) + return fndClk[clkCnt]; + } + return 0; +} + // by marshmellow // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping) // maybe somehow adjust peak trimming value based on samples to fix? -int DetectASKClock(uint8_t dest[], size_t size, int clock) +// return start index of best starting position for that clock and return clock (by reference) +int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) +{ + size_t i=1; + uint8_t clk[] = {255,8,16,32,40,50,64,100,128,255}; + uint8_t clkEnd = 9; + uint8_t loopCnt = 255; //don't need to loop through entire array... + if (size <= loopCnt) return -1; //not enough samples + + //if we already have a valid clock + uint8_t clockFnd=0; + for (;i0; i--){ + if (clk[i] == ans) { + *clock = ans; + //clockFnd = i; + return 0; // for strong waves i don't use the 'best start position' yet... + //break; //clock found but continue to find best startpos [not yet] + } + } + } + } + + uint8_t ii; + uint8_t clkCnt, tol = 0; + uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; + uint8_t bestStart[]={0,0,0,0,0,0,0,0,0}; + size_t errCnt = 0; + size_t arrLoc, loopEnd; + + if (clockFnd>0) { + clkCnt = clockFnd; + clkEnd = clockFnd+1; + } + else clkCnt=1; + + //test each valid clock from smallest to greatest to see which lines up + for(; clkCnt < clkEnd; clkCnt++){ + if (clk[clkCnt] <= 32){ + tol=1; + }else{ + tol=0; + } + //if no errors allowed - keep start within the first clock + if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) loopCnt=clk[clkCnt]*2; + bestErr[clkCnt]=1000; + //try lining up the peaks by moving starting point (try first few clocks) + for (ii=0; ii < loopCnt; ii++){ + if (dest[ii] < peak && dest[ii] > low) continue; + + errCnt=0; + // now that we have the first one lined up test rest of wave array + loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1; + for (i=0; i < loopEnd; ++i){ + arrLoc = ii + (i * clk[clkCnt]); + if (dest[arrLoc] >= peak || dest[arrLoc] <= low){ + }else if (dest[arrLoc-tol] >= peak || dest[arrLoc-tol] <= low){ + }else if (dest[arrLoc+tol] >= peak || dest[arrLoc+tol] <= low){ + }else{ //error no peak detected + errCnt++; + } + } + //if we found no errors then we can stop here and a low clock (common clocks) + // this is correct one - return this clock + //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i); + if(errCnt==0 && clkCnt<7) { + if (!clockFnd) *clock = clk[clkCnt]; + return ii; + } + //if we found errors see if it is lowest so far and save it as best run + if(errCnt maxErr) return -1; + if (!clockFnd) *clock = clk[best]; + return bestStart[best]; +} + +//by marshmellow +//detect psk clock by reading each phase shift +// a phase shift is determined by measuring the sample length of each wave +int DetectPSKClock(uint8_t dest[], size_t size, int clock) { - int i=0; - int clk[]={8,16,32,40,50,64,100,128,256}; - int loopCnt = 256; //don't need to loop through entire array... - if (size= peak) || (dest[ii] <= low)){ - errCnt=0; - // now that we have the first one lined up test rest of wave array - for (i=0; i<((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ - if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ - }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ - }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ - }else{ //error no peak detected - errCnt++; - } - } - //if we found no errors then we can stop here - // this is correct one - return this clock - //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i); - if(errCnt==0 && clkCnt<6) return clk[clkCnt]; - //if we found errors see if it is lowest so far and save it as best run - if(errCnt= dest[i+2]){ + if (waveStart == 0) { + waveStart = i+1; + //PrintAndLog("DEBUG: waveStart: %d",waveStart); + } else { + waveEnd = i+1; + //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); + waveLenCnt = waveEnd-waveStart; + if (waveLenCnt > fc){ + firstFullWave = waveStart; + fullWaveLen=waveLenCnt; + break; + } + waveStart=0; + } + } + } + //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); + + //test each valid clock from greatest to smallest to see which lines up + for(clkCnt=7; clkCnt >= 1 ; clkCnt--){ + lastClkBit = firstFullWave; //set end of wave as clock align + waveStart = 0; + errCnt=0; + peakcnt=0; + //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit); + + for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){ + //top edge of wave = start of new wave + if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){ + if (waveStart == 0) { + waveStart = i+1; + waveLenCnt=0; + } else { //waveEnd + waveEnd = i+1; + waveLenCnt = waveEnd-waveStart; + if (waveLenCnt > fc){ + //if this wave is a phase shift + //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, ii: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+clk[clkCnt]-tol,ii+1,fc); + if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit + peakcnt++; + lastClkBit+=clk[clkCnt]; + } else if (i lastClkBit + clk[clkCnt] + tol + fc){ + lastClkBit+=clk[clkCnt]; //no phase shift but clock bit + } + waveStart=i+1; + } + } + } + if (errCnt == 0){ + return clk[clkCnt]; + } + if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt; + if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt; + } + //all tested with errors + //return the highest clk with the most peaks found + uint8_t best=7; + for (i=7; i>=1; i--){ + if (peaksdet[i] > peaksdet[best]) { + best = i; + } + //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]); + } + return clk[best]; } //by marshmellow -//detect psk clock by reading #peaks vs no peaks(or errors) -int DetectpskNRZClock(uint8_t dest[], size_t size, int clock) +//detect nrz clock by reading #peaks vs no peaks(or errors) +int DetectNRZClock(uint8_t dest[], size_t size, int clock) { - int i=0; - int clk[]={16,32,40,50,64,100,128,256}; - int loopCnt = 2048; //don't need to loop through entire array... + size_t i=0; + uint8_t clk[]={8,16,32,40,50,64,100,128,255}; + size_t loopCnt = 4096; //don't need to loop through entire array... + if (size == 0) return 0; if (size= peak || dest[i] <= low){ + peakcnt++; + } else { + if (peakcnt>0 && maxPeak < peakcnt){ + maxPeak = peakcnt; + } + peakcnt=0; } + } + peakcnt=0; + //test each valid clock from smallest to greatest to see which lines up + for(clkCnt=0; clkCnt < 8; ++clkCnt){ + //ignore clocks smaller than largest peak + if (clk[clkCnt]= peak) || (dest[ii] <= low)){ - errCnt=0; peakcnt=0; // now that we have the first one lined up test rest of wave array for (i=0; i < ((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ peakcnt++; - }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ - peakcnt++; - }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ - peakcnt++; - }else{ //error no peak detected - errCnt++; } } if(peakcnt>peaksdet[clkCnt]) { peaksdet[clkCnt]=peakcnt; - bestErr[clkCnt]=errCnt; } } } } - int iii=0; - int best=0; - //int ratio2; //debug - int ratio; - //int bits; - for (iii=0; iii < 7; ++iii){ - ratio=1000; - //ratio2=1000; //debug - //bits=size/clk[iii]; //debug - if (peaksdet[iii] > 0){ - ratio=bestErr[iii]/peaksdet[iii]; - if (((bestErr[best]/peaksdet[best]) > (ratio)+1)){ - best = iii; - } - //ratio2=bits/peaksdet[iii]; //debug + int iii=7; + uint8_t best=0; + for (iii=7; iii > 0; iii--){ + if (peaksdet[iii] > peaksdet[best]){ + best = iii; } - //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d, ratio: %d, bits: %d, peakbitr: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best],ratio, bits,ratio2); + //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]); } return clk[best]; } -// by marshmellow (attempt to get rid of high immediately after a low) -void pskCleanWave(uint8_t *BitStream, size_t size) -{ - int i; - int gap = 4; - int newLow=0; - int newHigh=0; - int high, low; - getHiLo(BitStream, size, &high, &low, 80, 90); - - for (i=0; i < size; ++i){ - if (newLow == 1){ - if (BitStream[i]>low){ - BitStream[i]=low+8; - gap--; - } - if (gap == 0){ - newLow=0; - gap=4; - } - }else if (newHigh == 1){ - if (BitStream[i]= high) newHigh=1; - } - return; -} - // by marshmellow // convert psk1 demod to psk2 demod // only transition waves are 1s @@ -933,7 +1039,9 @@ void psk1TOpsk2(uint8_t *BitStream, size_t size) size_t i=1; uint8_t lastBit=BitStream[0]; for (; i*size) gLen = *size; + int high, low; + if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter + size_t iii = 0, bitnum = 0; //bitnum counter + uint16_t errCnt = 0, MaxBits = 1000; + size_t bestErrCnt = maxErr+1; + size_t bestPeakCnt = 0, bestPeakStart = 0; + uint8_t bestFirstPeakHigh=0, firstPeakHigh=0, curBit=0, bitHigh=0, errBitHigh=0; uint8_t tol = 1; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - if (*clk==32) tol = 2; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - uint32_t iii = 0; - uint8_t errCnt =0; - uint32_t bestStart = *size; - uint32_t maxErr = (*size/1000); - uint32_t bestErrCnt = maxErr; - uint8_t curBit=0; - uint8_t bitHigh=0; - uint8_t ignorewin=*clk/8; - //PrintAndLog("DEBUG - lastbit - %d",lastBit); + uint16_t peakCnt=0; + uint8_t ignoreWindow=4; + uint8_t ignoreCnt=ignoreWindow; //in case of noise near peak //loop to find first wave that works - align to clock for (iii=0; iii < gLen; ++iii){ if ((dest[iii]>=high) || (dest[iii]<=low)){ + if (dest[iii]>=high) firstPeakHigh=1; + else firstPeakHigh=0; lastBit=iii-*clk; + peakCnt=0; + errCnt=0; //loop through to see if this start location works for (i = iii; i < *size; ++i) { - //if we found a high bar and we are at a clock bit - if ((dest[i]>=high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ - bitHigh=1; - lastBit+=*clk; - ignorewin=*clk/8; - bitnum++; - //else if low bar found and we are at a clock point - }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ - bitHigh=1; - lastBit+=*clk; - ignorewin=*clk/8; - bitnum++; + // if we are at a clock bit + if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) { + //test high/low + if (dest[i] >= high || dest[i] <= low) { + bitHigh = 1; + peakCnt++; + errBitHigh = 0; + ignoreCnt = ignoreWindow; + lastBit += *clk; + } else if (i == lastBit + *clk + tol) { + lastBit += *clk; + } //else if no bars found - }else if(dest[i] < high && dest[i] > low) { - if (ignorewin==0){ + } else if (dest[i] < high && dest[i] > low){ + if (ignoreCnt==0){ bitHigh=0; - }else ignorewin--; - //if we are past a clock point - if (i >= lastBit+*clk+tol){ //clock val - lastBit+=*clk; - bitnum++; + if (errBitHigh==1) errCnt++; + errBitHigh=0; + } else { + ignoreCnt--; } - //else if bar found but we are not at a clock bit and we did not just have a clock bit - }else if ((dest[i]>=high || dest[i]<=low) && (ilastBit+*clk+tol) && (bitHigh==0)){ + } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) { //error bar found no clock... - errCnt++; + errBitHigh=1; } - if (bitnum>=1000) break; + if (((i-iii) / *clk)>=MaxBits) break; } //we got more than 64 good bits and not all errors - if ((bitnum > (64+errCnt)) && (errCnt < (maxErr))) { + if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) { //possible good read - if (errCnt == 0){ - bestStart = iii; + if (!errCnt || peakCnt > bestPeakCnt){ + bestFirstPeakHigh=firstPeakHigh; bestErrCnt = errCnt; - break; //great read - finish - } - if (errCnt < bestErrCnt){ //set this as new best run - bestErrCnt = errCnt; - bestStart = iii; + bestPeakCnt = peakCnt; + bestPeakStart = iii; + if (!errCnt) break; //great read - finish } } } } - if (bestErrCnt < maxErr){ - //best run is good enough set to best run and set overwrite BinStream - iii=bestStart; - lastBit=bestStart-*clk; - bitnum=0; - for (i = iii; i < *size; ++i) { - //if we found a high bar and we are at a clock bit - if ((dest[i] >= high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ - bitHigh=1; - lastBit+=*clk; - curBit=1-*invert; - dest[bitnum]=curBit; - ignorewin=*clk/8; - bitnum++; - //else if low bar found and we are at a clock point - }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ - bitHigh=1; - lastBit+=*clk; - curBit=*invert; - dest[bitnum]=curBit; - ignorewin=*clk/8; - bitnum++; - //else if no bars found - }else if(dest[i]low) { - if (ignorewin==0){ - bitHigh=0; - }else ignorewin--; - //if we are past a clock point - if (i>=lastBit+*clk+tol){ //clock val - lastBit+=*clk; - dest[bitnum]=curBit; - bitnum++; + //PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart); + if (bestErrCnt > maxErr) return bestErrCnt; + + //best run is good enough set to best run and set overwrite BinStream + lastBit = bestPeakStart - *clk; + memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk); + bitnum += (bestPeakStart / *clk); + for (i = bestPeakStart; i < *size; ++i) { + // if expecting a clock bit + if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) { + // test high/low + if (dest[i] >= high || dest[i] <= low) { + peakCnt++; + bitHigh = 1; + errBitHigh = 0; + ignoreCnt = ignoreWindow; + curBit = *invert; + if (dest[i] >= high) curBit ^= 1; + dest[bitnum++] = curBit; + lastBit += *clk; + //else no bars found in clock area + } else if (i == lastBit + *clk + tol) { + dest[bitnum++] = curBit; + lastBit += *clk; + } + //else if no bars found + } else if (dest[i] < high && dest[i] > low){ + if (ignoreCnt == 0){ + bitHigh = 0; + if (errBitHigh == 1){ + dest[bitnum++] = 7; + errCnt++; } - //else if bar found but we are not at a clock bit and we did not just have a clock bit - }else if ((dest[i]>=high || dest[i]<=low) && ((ilastBit+*clk+tol)) && (bitHigh==0)){ - //error bar found no clock... - bitHigh=1; - dest[bitnum]=77; - bitnum++; - errCnt++; + errBitHigh=0; + } else { + ignoreCnt--; } - if (bitnum >=1000) break; + } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) { + //error bar found no clock... + errBitHigh=1; } - *size=bitnum; - } else{ - *size=bitnum; - *clk=bestStart; - return -1; + if (bitnum >= MaxBits) break; } - - if (bitnum>16){ - *size=bitnum; - } else return -1; - return errCnt; + *size = bitnum; + return bestErrCnt; } //by marshmellow //detects the bit clock for FSK given the high and low Field Clocks uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) { - uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; - uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; - uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; - uint8_t rfLensFnd = 0; - uint8_t lastFCcnt=0; - uint32_t fcCounter = 0; - uint16_t rfCounter = 0; - uint8_t firstBitFnd = 0; - size_t i; - - uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); - rfLensFnd=0; - fcCounter=0; - rfCounter=0; - firstBitFnd=0; - //PrintAndLog("DEBUG: fcTol: %d",fcTol); - // prime i to first up transition - for (i = 1; i < size-1; i++) - if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) - break; - - for (; i < size-1; i++){ - if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){ - // new peak - fcCounter++; - rfCounter++; - // if we got less than the small fc + tolerance then set it to the small fc - if (fcCounter < fcLow+fcTol) - fcCounter = fcLow; - else //set it to the large fc - fcCounter = fcHigh; - - //look for bit clock (rf/xx) - if ((fcCounterlastFCcnt)){ - //not the same size as the last wave - start of new bit sequence - - if (firstBitFnd>1){ //skip first wave change - probably not a complete bit - for (int ii=0; ii<15; ii++){ - if (rfLens[ii]==rfCounter){ - rfCnts[ii]++; - rfCounter=0; - break; - } - } - if (rfCounter>0 && rfLensFnd<15){ - //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); - rfCnts[rfLensFnd]++; - rfLens[rfLensFnd++]=rfCounter; - } - } else { - firstBitFnd++; - } - rfCounter=0; - lastFCcnt=fcCounter; - } - fcCounter=0; - } else { - // count sample - fcCounter++; - rfCounter++; - } - } - uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; - - for (i=0; i<15; i++){ - //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); - //get highest 2 RF values (might need to get more values to compare or compare all?) - if (rfCnts[i]>rfCnts[rfHighest]){ - rfHighest3=rfHighest2; - rfHighest2=rfHighest; - rfHighest=i; - } else if(rfCnts[i]>rfCnts[rfHighest2]){ - rfHighest3=rfHighest2; - rfHighest2=i; - } else if(rfCnts[i]>rfCnts[rfHighest3]){ - rfHighest3=i; - } - } - // set allowed clock remainder tolerance to be 1 large field clock length+1 - // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off - uint8_t tol1 = fcHigh+1; - - //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); - - // loop to find the highest clock that has a remainder less than the tolerance - // compare samples counted divided by - int ii=7; - for (; ii>=0; ii--){ - if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ - if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ - if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ - break; - } - } - } - } - - if (ii<0) return 0; // oops we went too far - - return clk[ii]; + uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; + uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfLensFnd = 0; + uint8_t lastFCcnt = 0; + uint16_t fcCounter = 0; + uint16_t rfCounter = 0; + uint8_t firstBitFnd = 0; + size_t i; + if (size == 0) return 0; + + uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); + rfLensFnd=0; + fcCounter=0; + rfCounter=0; + firstBitFnd=0; + //PrintAndLog("DEBUG: fcTol: %d",fcTol); + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) + break; + + for (; i < size-1; i++){ + fcCounter++; + rfCounter++; + + if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1]) + continue; + // else new peak + // if we got less than the small fc + tolerance then set it to the small fc + if (fcCounter < fcLow+fcTol) + fcCounter = fcLow; + else //set it to the large fc + fcCounter = fcHigh; + + //look for bit clock (rf/xx) + if ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){ + //not the same size as the last wave - start of new bit sequence + if (firstBitFnd > 1){ //skip first wave change - probably not a complete bit + for (int ii=0; ii<15; ii++){ + if (rfLens[ii] == rfCounter){ + rfCnts[ii]++; + rfCounter = 0; + break; + } + } + if (rfCounter > 0 && rfLensFnd < 15){ + //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); + rfCnts[rfLensFnd]++; + rfLens[rfLensFnd++] = rfCounter; + } + } else { + firstBitFnd++; + } + rfCounter=0; + lastFCcnt=fcCounter; + } + fcCounter=0; + } + uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; + + for (i=0; i<15; i++){ + //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); + //get highest 2 RF values (might need to get more values to compare or compare all?) + if (rfCnts[i]>rfCnts[rfHighest]){ + rfHighest3=rfHighest2; + rfHighest2=rfHighest; + rfHighest=i; + } else if(rfCnts[i]>rfCnts[rfHighest2]){ + rfHighest3=rfHighest2; + rfHighest2=i; + } else if(rfCnts[i]>rfCnts[rfHighest3]){ + rfHighest3=i; + } + } + // set allowed clock remainder tolerance to be 1 large field clock length+1 + // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off + uint8_t tol1 = fcHigh+1; + + //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); + + // loop to find the highest clock that has a remainder less than the tolerance + // compare samples counted divided by + int ii=7; + for (; ii>=0; ii--){ + if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ + break; + } + } + } + } + + if (ii<0) return 0; // oops we went too far + + return clk[ii]; } //by marshmellow //countFC is to detect the field clock lengths. //counts and returns the 2 most common wave lengths -uint16_t countFC(uint8_t *BitStream, size_t size) +//mainly used for FSK field clock detection +uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) +{ + uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; + uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; + uint8_t fcLensFnd = 0; + uint8_t lastFCcnt=0; + uint8_t fcCounter = 0; + size_t i; + if (size == 0) return 0; + + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) + break; + + for (; i < size-1; i++){ + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ + // new up transition + fcCounter++; + if (fskAdj){ + //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) + if (lastFCcnt==5 && fcCounter==9) fcCounter--; + //if fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5) + if ((fcCounter==9) || fcCounter==4) fcCounter++; + // save last field clock count (fc/xx) + lastFCcnt = fcCounter; + } + // find which fcLens to save it to: + for (int ii=0; ii<10; ii++){ + if (fcLens[ii]==fcCounter){ + fcCnts[ii]++; + fcCounter=0; + break; + } + } + if (fcCounter>0 && fcLensFnd<10){ + //add new fc length + fcCnts[fcLensFnd]++; + fcLens[fcLensFnd++]=fcCounter; + } + fcCounter=0; + } else { + // count sample + fcCounter++; + } + } + + uint8_t best1=9, best2=9, best3=9; + uint16_t maxCnt1=0; + // go through fclens and find which ones are bigest 2 + for (i=0; i<10; i++){ + // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); + // get the 3 best FC values + if (fcCnts[i]>maxCnt1) { + best3=best2; + best2=best1; + maxCnt1=fcCnts[i]; + best1=i; + } else if(fcCnts[i]>fcCnts[best2]){ + best3=best2; + best2=i; + } else if(fcCnts[i]>fcCnts[best3]){ + best3=i; + } + } + uint8_t fcH=0, fcL=0; + if (fcLens[best1]>fcLens[best2]){ + fcH=fcLens[best1]; + fcL=fcLens[best2]; + } else{ + fcH=fcLens[best2]; + fcL=fcLens[best1]; + } + + // TODO: take top 3 answers and compare to known Field clocks to get top 2 + + uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; + // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); + if (fskAdj) return fcs; + return fcLens[best1]; +} + +//by marshmellow - demodulate PSK1 wave +//uses wave lengths (# Samples) +int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) { - uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; - uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; - uint8_t fcLensFnd = 0; - uint8_t lastFCcnt=0; - uint32_t fcCounter = 0; - size_t i; - - // prime i to first up transition - for (i = 1; i < size-1; i++) - if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) - break; - - for (; i < size-1; i++){ - if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ - // new up transition - fcCounter++; - - //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) - if (lastFCcnt==5 && fcCounter==9) fcCounter--; - //if odd and not rc/5 add one (for when we get a fc 9 instead of 10) - if ((fcCounter==9 && fcCounter & 1) || fcCounter==4) fcCounter++; - - // save last field clock count (fc/xx) - // find which fcLens to save it to: - for (int ii=0; ii<10; ii++){ - if (fcLens[ii]==fcCounter){ - fcCnts[ii]++; - fcCounter=0; - break; - } - } - if (fcCounter>0 && fcLensFnd<10){ - //add new fc length - fcCnts[fcLensFnd]++; - fcLens[fcLensFnd++]=fcCounter; - } - fcCounter=0; - } else { - // count sample - fcCounter++; - } - } - - uint8_t best1=9, best2=9, best3=9; - uint16_t maxCnt1=0; - // go through fclens and find which ones are bigest 2 - for (i=0; i<10; i++){ - // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); - // get the 3 best FC values - if (fcCnts[i]>maxCnt1) { - best3=best2; - best2=best1; - maxCnt1=fcCnts[i]; - best1=i; - } else if(fcCnts[i]>fcCnts[best2]){ - best3=best2; - best2=i; - } else if(fcCnts[i]>fcCnts[best3]){ - best3=i; - } - } - uint8_t fcH=0, fcL=0; - if (fcLens[best1]>fcLens[best2]){ - fcH=fcLens[best1]; - fcL=fcLens[best2]; - } else{ - fcH=fcLens[best2]; - fcL=fcLens[best1]; - } - - // TODO: take top 3 answers and compare to known Field clocks to get top 2 - - uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; - // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); - - return fcs; + if (size == 0) return -1; + uint16_t loopCnt = 4096; //don't need to loop through entire array... + if (*size= dest[i+2]){ + waveEnd = i+1; + //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); + waveLenCnt = waveEnd-waveStart; + if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave + lastAvgWaveVal = avgWaveVal/(waveLenCnt); + firstFullWave = waveStart; + fullWaveLen=waveLenCnt; + //if average wave value is > graph 0 then it is an up wave or a 1 + if (lastAvgWaveVal > 123) curPhase ^= 1; //fudge graph 0 a little 123 vs 128 + break; + } + waveStart = i+1; + avgWaveVal = 0; + } + avgWaveVal += dest[i+2]; + } + //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); + lastClkBit = firstFullWave; //set start of wave as clock align + //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit); + waveStart = 0; + size_t numBits=0; + //set skipped bits + memset(dest, curPhase^1, firstFullWave / *clock); + numBits += (firstFullWave / *clock); + dest[numBits++] = curPhase; //set first read bit + for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){ + //top edge of wave = start of new wave + if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ + if (waveStart == 0) { + waveStart = i+1; + waveLenCnt = 0; + avgWaveVal = dest[i+1]; + } else { //waveEnd + waveEnd = i+1; + waveLenCnt = waveEnd-waveStart; + lastAvgWaveVal = avgWaveVal/waveLenCnt; + if (waveLenCnt > fc){ + //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal); + //this wave is a phase shift + //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc); + if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit + curPhase ^= 1; + dest[numBits++] = curPhase; + lastClkBit += *clock; + } else if (i < lastClkBit+10+fc){ + //noise after a phase shift - ignore + } else { //phase shift before supposed to based on clock + errCnt++; + dest[numBits++] = 7; + } + } else if (i+1 > lastClkBit + *clock + tol + fc){ + lastClkBit += *clock; //no phase shift but clock bit + dest[numBits++] = curPhase; + } + avgWaveVal = 0; + waveStart = i+1; + } + } + avgWaveVal += dest[i+1]; + } + *size = numBits; + return errCnt; }