X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/0644d5e3a3ed255fea1084c0af564c00f592b36c..327a690813ff04d580a2630977f160b8ec809bd9:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 88a250d8..92ad633e 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -25,7 +25,7 @@ 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; @@ -50,12 +50,12 @@ 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; @@ -75,63 +75,64 @@ uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_ 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}; + // 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; - 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]); - } + 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 lo; - //skip last 5 bit parity test for simplicity. - // *size = 64; } + 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 +//takes 3 arguments - clock, invert, maxErr 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) +int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr) { int i; - int clk2=*clk; - *clk=DetectASKClock(BinStream, *size, *clk); //clock default - + //int clk2=*clk; + int start = DetectASKClock(BinStream, *size, clk, 20); //clock default + if (*clk==0) return -3; + if (start < 0) return -3; // if autodetected too low then adjust //MAY NEED ADJUSTMENT - if (clk2==0 && *clk<8) *clk =64; - if (clk2==0 && *clk<32) *clk=32; + //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; @@ -145,14 +146,16 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) 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 + 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; + //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance + if (!maxErr) gLen=*clk*2; uint8_t errCnt =0; + uint16_t MaxBits = 500; uint32_t bestStart = *size; - uint32_t bestErrCnt = (*size/1000); - uint32_t maxErr = (*size/1000); + int bestErrCnt = maxErr+1; // PrintAndLog("DEBUG - lastbit - %d",lastBit); // loop to find first wave that works for (iii=0; iii < gLen; ++iii){ @@ -179,10 +182,10 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over } } - if ((i-iii) >(400 * *clk)) break; //got plenty of bits + if ((i-iii) >(MaxBits * *clk)) break; //got plenty of bits } //we got more than 64 good bits and not all errors - if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt (64)) && (errCnt<=maxErr)) { //possible good read if (errCnt==0){ bestStart=iii; @@ -196,7 +199,7 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) } } } - if (bestErrCnt=400) break; + if (bitnum >=MaxBits) break; } *size=bitnum; } else{ @@ -243,14 +246,14 @@ 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; + 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 @@ -258,21 +261,19 @@ int ManchesterEncode(uint8_t *BitStream, size_t size) //run through 2 times and take least errCnt int manrawdecode(uint8_t * BitStream, size_t *size) { - 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; + uint16_t bitnum=0, MaxBits = 512, errCnt = 0; + size_t i, ii; + uint16_t bestErr = 1000, bestRun = 0; + if (size == 0) return -1; + for (ii=0;ii<2;++ii){ + i=0; 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 { errCnt++; } - if(bitnum>300) break; + if(bitnum>MaxBits) break; } if (bestErr>errCnt){ bestErr=errCnt; @@ -283,8 +284,8 @@ int manrawdecode(uint8_t * BitStream, size_t *size) errCnt=bestErr; if (errCnt<20){ ii=bestRun; - i=1; - for (i=i+ii;i < *size-2;i+=2){ + i=0; + 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){ @@ -293,7 +294,7 @@ int manrawdecode(uint8_t * BitStream, size_t *size) BitStream[bitnum++]=77; //errCnt++; } - if(bitnum>300) break; + if(bitnum>MaxBits) break; } *size=bitnum; } @@ -301,14 +302,30 @@ int manrawdecode(uint8_t * BitStream, size_t *size) } //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; + uint16_t bitnum=0; uint32_t errCnt =0; - uint32_t i; - i=offset; - for (;i<*size-2; i+=2){ + 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++]=77; + 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)){ @@ -317,56 +334,135 @@ int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) BitStream[bitnum++]=77; errCnt++; } - if(bitnum>250) break; + if(bitnum>MaxBits) break; } *size=bitnum; return errCnt; } //by marshmellow -//takes 2 arguments - clock and invert both as integers +void askAmp(uint8_t *BitStream, size_t size) +{ + int shift = 127; + int shiftedVal=0; + for(int i = 1; i=30) //large jump up + shift=127; + else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down + shift=-127; + + shiftedVal=BitStream[i]+shift; + + if (shiftedVal>255) + shiftedVal=255; + else if (shiftedVal<0) + shiftedVal=0; + BitStream[i-1] = shiftedVal; + } + return; +} + +int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low) +{ + size_t bitCnt=0, smplCnt=0, errCnt=0; + uint8_t waveHigh = 0; + //PrintAndLog("clk: %d", clk); + 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++; + BinStream[bitCnt++]=77; + } 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 + } + } else { //haven't hit new high or new low yet + smplCnt++; + } + } + } + *size = bitCnt; + return errCnt; +} + +//by marshmellow +//takes 3 arguments - clock, invert and maxErr 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) +int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp) { 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 (*size==0) return -1; + int start = DetectASKClock(BinStream, *size, clk, 20); //clock default + if (*clk==0) return -1; + if (start<0) return -1; if (*invert != 0 && *invert != 1) *invert =0; + if (amp==1) askAmp(BinStream, *size); + uint32_t initLoopMax = 200; if (initLoopMax > *size) initLoopMax=*size; // Detect high and lows - //25% fuzz in case highs and lows aren't clipped [marshmellow] + //25% clip in case highs and lows aren't clipped [marshmellow] + uint8_t clip = 75; int high, low, ans; - ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); - if (ans<1) return -2; //just noise + ans = getHiLo(BinStream, initLoopMax, &high, &low, clip, clip); + if (ans<1) return -1; //just noise + + if (DetectCleanAskWave(BinStream, *size, high, low)) { + //PrintAndLog("Clean"); + return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); + } //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 + if (*clk == 32) tol=0; //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; + //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance + if (!maxErr) gLen = *clk * 2; uint8_t errCnt =0; uint32_t bestStart = *size; - uint32_t bestErrCnt = (*size/1000); - uint32_t maxErr = bestErrCnt; + uint32_t bestErrCnt = maxErr; //(*size/1000); uint8_t midBit=0; + uint16_t MaxBits=1000; + //PrintAndLog("DEBUG - lastbit - %d",lastBit); //loop to find first wave that works - for (iii=0; iii < gLen; ++iii){ + for (iii=start; 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))){ @@ -395,16 +491,16 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) 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; + if (errCnt > maxErr){ + //errCnt=0; break; } } } - if ((i-iii)>(500 * *clk)) break; //got enough bits + if ((i-iii)>(MaxBits * *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))) { + if ((((i-iii)/ *clk) > (64)) && (errCnt<=maxErr)) { //possible good read if (errCnt==0){ bestStart=iii; @@ -418,9 +514,9 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) } } } - if (bestErrCnt (*clk-tol))){ //low found and we are expecting a bar lastBit+=*clk; - BinStream[bitnum] = 1-*invert; + BinStream[bitnum] = 1 - *invert; bitnum++; midBit=0; } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ @@ -462,11 +558,10 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) BinStream[bitnum]=77; bitnum++; } - lastBit+=*clk;//skip over error } } - if (bitnum >=400) break; + if (bitnum >= MaxBits) break; } *size=bitnum; } else{ @@ -476,6 +571,28 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) } return bestErrCnt; } + +// 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) +{ + size_t startIdx=0; + uint8_t preamble[] = {1,1,1,1,1,0}; + + 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 -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) { @@ -510,7 +627,9 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow //do nothing with extra garbage } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves dest[numBits]=1; - } else { //9+ = 10 waves + } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage + //do nothing with beginning garbage + } else { //9+ = 10 waves dest[numBits]=0; } last_transition = idx; @@ -534,18 +653,31 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxCons uint32_t idx=0; size_t numBits=0; uint32_t n=1; - + float lowWaves = (((float)(rfLen))/((float)fclow)); + float highWaves = (((float)(rfLen))/((float)fchigh)); for( idx=1; idx < size; idx++) { if (dest[idx]==lastval) { n++; continue; } + n++; //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 < (uint8_t)lowWaves) { + n=0; + lastval = dest[idx]; + continue; + } + n=myround2(((float)n)/lowWaves); + } else {// 0->1 crossing + //test first bitsample too small + if (!numBits && n < (uint8_t)highWaves) { + n=0; + lastval = dest[idx]; + continue; + } + n = myround2(((float)n)/highWaves); //-1 for fudge factor } if (n == 0) n = 1; @@ -561,6 +693,17 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxCons n=0; lastval=dest[idx]; }//end for + + // if valid extra bits at the end were all the same frequency - add them in + if (n > lowWaves && n > highWaves) { + if (dest[idx-2]==1) { + n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); + } else { + n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor + } + memset(dest, dest[idx-1]^invert , n); + numBits += n; + } return numBits; } //by marshmellow (from holiman's base) @@ -688,7 +831,7 @@ 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--; // if parity fails then return 0 @@ -726,17 +869,17 @@ 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 @@ -744,40 +887,120 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size) return (int)startIdx; } + +uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low) +{ + uint16_t allPeaks=1; + uint16_t cntPeaks=0; + size_t loopEnd = 572; + if (loopEnd > size) loopEnd = size; + for (size_t i=60; ilow && dest[i] 300) return 1; + } + return allPeaks; +} + +int DetectStrongAskClock(uint8_t dest[], size_t size) +{ + int clk[]={0,8,16,32,40,50,64,100,128,256}; + size_t idx = 40; + uint8_t high=0; + size_t cnt = 0; + size_t highCnt = 0; + size_t highCnt2 = 0; + for (;idx < size; idx++){ + if (dest[idx]>128) { + if (!high){ + high=1; + if (cnt > highCnt){ + if (highCnt != 0) highCnt2 = highCnt; + highCnt = cnt; + } else if (cnt > highCnt2) { + highCnt2 = cnt; + } + cnt=1; + } else { + cnt++; + } + } else if (dest[idx] <= 128){ + if (high) { + high=0; + if (cnt > highCnt) { + if (highCnt != 0) highCnt2 = highCnt; + highCnt = cnt; + } else if (cnt > highCnt2) { + highCnt2 = cnt; + } + cnt=1; + } else { + cnt++; + } + } + } + uint8_t tol; + for (idx=8; idx>0; idx--){ + tol = clk[idx]/8; + if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol) + return clk[idx]; + if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol) + return clk[idx]; + } + return -1; +} + // 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) { 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 == 0) return -1; if (size0; i--){ + if (clk[i] == ans) { + *clock=ans; + return 0; + } + } + } int ii; int clkCnt; int tol = 0; int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; + int bestStart[]={0,0,0,0,0,0,0,0,0}; int errCnt=0; //test each valid clock from smallest to greatest to see which lines up - for(clkCnt=0; clkCnt < 8; ++clkCnt){ + for(clkCnt=0; clkCnt < 8; clkCnt++){ if (clk[clkCnt] == 32){ tol=1; }else{ tol=0; } + if (!maxErr) loopCnt=clk[clkCnt]*2; bestErr[clkCnt]=1000; //try lining up the peaks by moving starting point (try first 256) - for (ii=0; ii < loopCnt; ++ii){ + for (ii=0; ii < loopCnt; ii++){ if ((dest[ii] >= peak) || (dest[ii] <= low)){ errCnt=0; // now that we have the first one lined up test rest of wave array @@ -792,9 +1015,15 @@ int DetectASKClock(uint8_t dest[], size_t size, int clock) //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(errCnt==0 && clkCnt<6) { + *clock = clk[clkCnt]; + return ii; + } //if we found errors see if it is lowest so far and save it as best run - if(errCntmaxErr) return -1; + *clock=clk[best]; + return bestStart[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 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[]={16,32,40,50,64,100,128,256}; - int loopCnt = 2048; //don't need to loop through entire array... - if (size= 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 - } - //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); - } - return clk[best]; + size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0; + uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1; + uint16_t peakcnt=0, errCnt=0, waveLenCnt=0; + uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; + uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0}; + countFC(dest, size, &fc); + //PrintAndLog("DEBUG: FC: %d",fc); + + //find first full wave + for (i=0; i= 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 (attempt to get rid of high immediately after a low) -void pskCleanWave(uint8_t *BitStream, size_t size) +//by marshmellow +//detect nrz clock by reading #peaks vs no peaks(or errors) +int DetectNRZClock(uint8_t dest[], size_t size, int clock) { - 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; + int i=0; + int clk[]={8,16,32,40,50,64,100,128,256}; + int 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)){ + 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++; + } + } + if(peakcnt>peaksdet[clkCnt]) { + peaksdet[clkCnt]=peakcnt; + } + } + } + } + int iii=7; + int 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",clk[iii],peaksdet[iii],bestErr[iii],clk[best]); + } + return clk[best]; } // by marshmellow @@ -933,7 +1217,9 @@ void psk1TOpsk2(uint8_t *BitStream, size_t size) size_t i=1; uint8_t lastBit=BitStream[0]; for (; i=high) || (dest[iii]<=low)){ - lastBit=iii-*clk; - //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++; - //else if no bars found - }else if(dest[i] < high && 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; - bitnum++; - } - //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... - errCnt++; - } - if (bitnum>=1000) break; - } - //we got more than 64 good bits and not all errors - if ((bitnum > (64+errCnt)) && (errCnt < (maxErr))) { - //possible good read - if (errCnt == 0){ - bestStart = iii; - bestErrCnt = errCnt; - break; //great read - finish - } - if (errCnt < bestErrCnt){ //set this as new best run - bestErrCnt = errCnt; - bestStart = iii; - } - } - } - } - 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++; - } - //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++; - } - if (bitnum >=1000) break; - } - *size=bitnum; - } else{ - *size=bitnum; - *clk=bestStart; - return -1; - } + if (justNoise(dest, *size)) return -1; + *clk = DetectNRZClock(dest, *size, *clk); + if (*clk==0) return -2; + uint32_t i; + uint32_t gLen = 4096; + if (gLen>*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 + 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 + uint32_t iii = 0; + uint16_t errCnt =0; + uint16_t MaxBits = 1000; + uint32_t bestErrCnt = maxErr+1; + uint32_t bestPeakCnt = 0; + uint32_t bestPeakStart=0; + uint8_t bestFirstPeakHigh=0; + uint8_t firstPeakHigh=0; + uint8_t curBit=0; + uint8_t bitHigh=0; + uint8_t errBitHigh=0; + uint16_t peakCnt=0; + uint8_t ignoreWindow=4; + uint8_t ignoreCnt=ignoreWindow; //in case of noice 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; + bitnum=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; + bitnum++; + peakCnt++; + errBitHigh=0; + ignoreCnt=ignoreWindow; + //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; + bitnum++; + peakCnt++; + errBitHigh=0; + ignoreCnt=ignoreWindow; + //else if no bars found + }else if(dest[i] < high && dest[i] > low) { + if (ignoreCnt==0){ + bitHigh=0; + if (errBitHigh==1){ + errCnt++; + } + errBitHigh=0; + } else { + ignoreCnt--; + } + //if we are past a clock point + if (i >= lastBit+*clk+tol){ //clock val + lastBit+=*clk; + bitnum++; + } + //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... + errBitHigh=1; + } + if (bitnum>=MaxBits) break; + } + //we got more than 64 good bits and not all errors + if (bitnum > (64) && (errCnt <= (maxErr))) { + //possible good read + if (errCnt == 0){ + //bestStart = iii; + bestFirstPeakHigh=firstPeakHigh; + bestErrCnt = errCnt; + bestPeakCnt = peakCnt; + bestPeakStart = iii; + break; //great read - finish + } + if (errCnt < bestErrCnt){ //set this as new best run + bestErrCnt = errCnt; + //bestStart = iii; + } + if (peakCnt > bestPeakCnt){ + bestFirstPeakHigh=firstPeakHigh; + bestPeakCnt=peakCnt; + bestPeakStart=iii; + } + } + } + } + //PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart); + if (bestErrCnt <= maxErr){ + //best run is good enough set to best run and set overwrite BinStream + iii=bestPeakStart; + lastBit=bestPeakStart-*clk; + bitnum=0; + memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk); + bitnum += (bestPeakStart / *clk); + 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; + bitnum++; + errBitHigh=0; + ignoreCnt=ignoreWindow; + //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; + bitnum++; + errBitHigh=0; + ignoreCnt=ignoreWindow; + //else if no bars found + }else if(dest[i]low) { + if (ignoreCnt==0){ + bitHigh=0; + //if peak is done was it an error peak? + if (errBitHigh==1){ + dest[bitnum]=77; + bitnum++; + errCnt++; + } + errBitHigh=0; + } else { + ignoreCnt--; + } + //if we are past a clock point + if (i>=lastBit+*clk+tol){ //clock val + lastBit+=*clk; + dest[bitnum]=curBit; + bitnum++; + } + //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... + errBitHigh=1; + } + if (bitnum >= MaxBits) break; + } + *size=bitnum; + } else{ + *size=bitnum; + return bestErrCnt; + } - if (bitnum>16){ - *size=bitnum; - } else return -1; - return errCnt; + if (bitnum>16){ + *size=bitnum; + } else return -5; + return errCnt; } //by marshmellow @@ -1153,6 +1490,7 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc 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; @@ -1175,7 +1513,7 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc 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 @@ -1249,7 +1587,8 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc //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 *mostFC) { 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}; @@ -1257,7 +1596,8 @@ uint16_t countFC(uint8_t *BitStream, size_t size) uint8_t lastFCcnt=0; uint32_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]) @@ -1320,7 +1660,8 @@ uint16_t countFC(uint8_t *BitStream, size_t size) fcH=fcLens[best2]; fcL=fcLens[best1]; } - + + *mostFC=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; @@ -1328,3 +1669,146 @@ uint16_t countFC(uint8_t *BitStream, size_t size) return fcs; } + +//by marshmellow +//countPSK_FC is to detect the psk carrier clock length. +//counts and returns the 1 most common wave length +uint8_t countPSK_FC(uint8_t *BitStream, size_t size) +{ + 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; + uint32_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++; + + // 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; + uint16_t maxCnt1=0; + // go through fclens and find which ones are bigest + for (i=0; i<10; i++){ + //PrintAndLog("DEBUG: FC %d, Cnt %d",fcLens[i],fcCnts[i]); + // get the best FC value + if (fcCnts[i]>maxCnt1) { + maxCnt1=fcCnts[i]; + best1=i; + } + } + return fcLens[best1]; +} + +//by marshmellow - demodulate PSK1 wave +//uses wave lengths (# Samples) +int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) +{ + uint16_t loopCnt = 4096; //don't need to loop through entire array... + if (size == 0) return -1; + 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; + errCnt=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); + //if 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 + *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; +}