X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/d5d6f22718903a68bd097b6e276f3eaa33ca3788..6ef3f9f219240a5868ff1079070102f27d818b49:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index ffa807fe..3f597a1f 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -9,8 +9,22 @@ //----------------------------------------------------------------------------- #include -#include #include "lfdemod.h" +#include + +//to allow debug print calls when used not on device +void dummy(char *fmt, ...){} + +#ifndef ON_DEVICE +#include "ui.h" +#include "cmdparser.h" +#include "cmddata.h" +#define prnt PrintAndLog +#else + uint8_t g_debugMode=0; +#define prnt dummy +#endif + uint8_t justNoise(uint8_t *BitStream, size_t size) { static const uint8_t THRESHOLD = 123; @@ -48,283 +62,185 @@ 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); + if (g_debugMode) prnt("DEBUG: ans: %d, ptype: %d, bits: %08X",ans,pType,bits); return (ans == pType); } -//by marshmellow -//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) +// 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; 2 for Always 1's; 3 for Always 0'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) { - 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; - } + uint32_t parityWd = 0; + size_t j = 0, bitCnt = 0; + 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]); } - } - return 0; -} + if (word+pLen > bLen) break; -//by marshmellow -//takes 1s and 0s and searches for EM410x format - output EM ID -uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) -{ - //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){ //allow only 1s and 0s - // PrintAndLog("no data found"); - return 0; - } - // 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]); + j--; // overwrite parity with next data + // if parity fails then return 0 + switch (pType) { + case 3: if (BitStream[j]==1) {return 0;} break; //should be 0 spacer bit + case 2: if (BitStream[j]==0) {return 0;} break; //should be 1 spacer bit + default: if (parityTest(parityWd, pLen, pType) == 0) {return 0;} break; //test parity } + bitCnt+=(pLen-1); + parityWd = 0; } - if (errChk != 0) return 1; - //skip last 5 bit parity test for simplicity. - // *size = 64 | 128; - return 0; + // if we got here then all the parities passed + //return ID start index and size + return bitCnt; } -//by marshmellow -//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 maxErr) +// by marshmellow +// takes a array of binary values, length of bits per parity (includes parity bit), +// Parity Type (1 for odd; 0 for even; 2 Always 1's; 3 Always 0's), and binary Length (length to run) +// Make sure *dest is long enough to store original sourceLen + #_of_parities_to_be_added +size_t addParity(uint8_t *BitSource, uint8_t *dest, uint8_t sourceLen, uint8_t pLen, uint8_t pType) { - size_t i; - int start = DetectASKClock(BinStream, *size, clk, 20); //clock default - if (*clk==0 || start < 0) return -3; - if (*invert != 1) *invert=0; - uint8_t initLoopMax = 255; - if (initLoopMax > *size) initLoopMax = *size; - // Detect high and lows - // 25% fuzz 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 - - // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check - uint16_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 - size_t iii = 0; - //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance - if (!maxErr) initLoopMax = *clk * 2; - uint16_t errCnt = 0, MaxBits = 512; - uint16_t bestStart = start; - uint16_t bestErrCnt = 0; - // PrintAndLog("DEBUG - lastbit - %d",lastBit); - // if best start position not already found by detect clock then - if (start <= 0 || start > initLoopMax){ - bestErrCnt = maxErr+1; - // loop to find first wave that works - for (iii=0; iii < initLoopMax; ++iii){ - // if no peak skip - if (BinStream[iii] < high && BinStream[iii] > low) continue; - - lastBit = iii - *clk; - // loop through to see if this start location works - for (i = iii; i < *size; ++i) { - if ((i-lastBit) > (*clk-tol) && (BinStream[i] >= high || BinStream[i] <= low)) { - lastBit += *clk; - } else if ((i-lastBit) > (*clk+tol)) { - errCnt++; - lastBit += *clk; - } - if ((i-iii) > (MaxBits * *clk) || errCnt > maxErr) break; //got plenty of bits or too many errors - } - //we got more than 64 good bits and not all errors - if ((((i-iii)/ *clk) > (64)) && (errCnt<=maxErr)) { - //possible good read - if (!errCnt || errCnt < bestErrCnt){ - bestStart = iii; //set this as new best run - bestErrCnt = errCnt; - if (!errCnt) break; //great read - finish - } - } - errCnt = 0; + uint32_t parityWd = 0; + size_t j = 0, bitCnt = 0; + for (int word = 0; word < sourceLen; word+=pLen-1) { + for (int bit=0; bit < pLen-1; bit++){ + parityWd = (parityWd << 1) | BitSource[word+bit]; + dest[j++] = (BitSource[word+bit]); } - } - if (bestErrCnt > maxErr){ - *invert = bestStart; - *clk = iii; - return -1; - } - //best run is good enough set to best run and set overwrite BinStream - lastBit = bestStart - *clk; - errCnt = 0; - for (i = bestStart; i < *size; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ - //high found and we are expecting a bar - lastBit += *clk; - BinStream[bitnum++] = *invert; - } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ - //low found and we are expecting a bar - lastBit += *clk; - BinStream[bitnum++] = *invert ^ 1; - } else if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - //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; - errCnt++; - } - lastBit += *clk;//skip over error + // if parity fails then return 0 + switch (pType) { + case 3: dest[j++]=0; break; // marker bit which should be a 0 + case 2: dest[j++]=1; break; // marker bit which should be a 1 + default: + dest[j++] = parityTest(parityWd, pLen-1, pType) ^ 1; + break; } - if (bitnum >= MaxBits) break; + bitCnt += pLen; + parityWd = 0; } - *size = bitnum; - return bestErrCnt; + // if we got here then all the parities passed + //return ID start index and size + return bitCnt; } -//by marshmellow -//encode binary data into binary manchester -int ManchesterEncode(uint8_t *BitStream, size_t size) +uint32_t bytebits_to_byte(uint8_t *src, size_t numbits) { - 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; + uint32_t num = 0; + for(int i = 0 ; i < numbits ; i++) + { + num = (num << 1) | (*src); + src++; } - for (; i<(size*2); i++){ - BitStream[i] = BitStream[i+20000]; + 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 i; + return num; } //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) +//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) { - 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){ - for (i=ii; i<*size-2; i+=2) - if (BitStream[i]==BitStream[i+1]) - errCnt++; + return (preambleSearchEx(BitStream, preamble, pLen, size, startIdx, false)) ? 1 : 0; +} - if (bestErr>errCnt){ - bestErr=errCnt; - bestRun=ii; - } - errCnt=0; - } - if (bestErr<20){ - for (i=bestRun; 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; +// search for given preamble in given BitStream and return success=1 or fail=0 and startIndex (where it was found) and length if not fineone +// fineone does not look for a repeating preamble for em4x05/4x69 sends preamble once, so look for it once in the first pLen bits +bool preambleSearchEx(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone) { + // Sanity check. If preamble length is bigger than bitstream length. + if ( *size <= pLen ) return false; + + uint8_t foundCnt = 0; + for (size_t idx = 0; idx < *size - pLen; idx++) { + if (memcmp(BitStream+idx, preamble, pLen) == 0) { + //first index found + foundCnt++; + if (foundCnt == 1) { + if (g_debugMode) prnt("DEBUG: preamble found at %u", idx); + *startIdx = idx; + if (findone) return true; + } else if (foundCnt == 2) { + *size = idx - *startIdx; + return true; } - if(bitnum>MaxBits) break; } - *size=bitnum; } - return bestErr; + return false; } -//by marshmellow -//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) -{ - 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++]=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)){ - BitStream[bitnum++]=invert; +// find start of modulating data (for fsk and psk) in case of beginning noise or slow chip startup. +size_t findModStart(uint8_t dest[], size_t size, uint8_t threshold_value, uint8_t expWaveSize) { + size_t i = 0; + size_t waveSizeCnt = 0; + uint8_t thresholdCnt = 0; + bool isAboveThreshold = dest[i++] >= threshold_value; + for (; i < size-20; i++ ) { + if(dest[i] < threshold_value && isAboveThreshold) { + thresholdCnt++; + if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break; + isAboveThreshold = false; + waveSizeCnt = 0; + } else if (dest[i] >= threshold_value && !isAboveThreshold) { + thresholdCnt++; + if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break; + isAboveThreshold = true; + waveSizeCnt = 0; } else { - BitStream[bitnum++]=77; - errCnt++; + waveSizeCnt++; } - if(bitnum>MaxBits) break; + if (thresholdCnt > 10) break; } - *size=bitnum; - return errCnt; + if (g_debugMode == 2) prnt("DEBUG: threshold Count reached at %u, count: %u",i, thresholdCnt); + return i; } //by marshmellow -void askAmp(uint8_t *BitStream, size_t size) +//takes 1s and 0s and searches for EM410x format - output EM ID +uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) { - int shift = 127; - int shiftedVal=0; - for(size_t i = 1; i=30) //large jump up - shift=127; - else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down - shift=-127; + //sanity checks + if (*size < 64) return 0; + if (BitStream[1]>1) return 0; //allow only 1s and 0s - shiftedVal=BitStream[i]+shift; - - if (shiftedVal>255) - shiftedVal=255; - else if (shiftedVal<0) - shiftedVal=0; - BitStream[i-1] = shiftedVal; + // 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}; + uint8_t errChk = 0; + uint8_t FmtLen = 10; // sets of 4 bits = end data + *startIdx = 0; + errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); + if ( errChk == 0 || (*size != 64 && *size != 128) ) return 0; + if (*size == 128) FmtLen = 22; // 22 sets of 4 bits + + //skip last 4bit parity row for simplicity + *size = removeParity(BitStream, *startIdx + sizeof(preamble), 5, 0, FmtLen * 5); + if (*size == 40) { // std em410x format + *hi = 0; + *lo = ((uint64_t)(bytebits_to_byte(BitStream, 8)) << 32) | (bytebits_to_byte(BitStream + 8, 32)); + } else if (*size == 88) { // long em format + *hi = (bytebits_to_byte(BitStream, 24)); + *lo = ((uint64_t)(bytebits_to_byte(BitStream + 24, 32)) << 32) | (bytebits_to_byte(BitStream + 24 + 32, 32)); + } else { + return 0; } - return; + return 1; } -// demodulates strong heavily clipped samples +//by marshmellow +//demodulates strong heavily clipped samples 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++; @@ -335,7 +251,8 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int if (smplCnt > clk-(clk/4)-1) { //full clock if (smplCnt > clk + (clk/4)+1) { //too many samples errCnt++; - BinStream[bitCnt++]=77; + if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i); + BinStream[bitCnt++]=7; } else if (waveHigh) { BinStream[bitCnt++] = invert; BinStream[bitCnt++] = invert; @@ -371,111 +288,87 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int } //by marshmellow -//takes 3 arguments - clock, invert and maxErr as integers -//attempts to demodulate ask only -int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp) +//amplify based on ask edge detection +void askAmp(uint8_t *BitStream, size_t size) +{ + uint8_t Last = 128; + for(size_t i = 1; i=30) //large jump up + Last = 255; + else if(BitStream[i-1]-BitStream[i]>=20) //large jump down + Last = 0; + + BitStream[i-1] = Last; + } + return; +} + +//by marshmellow +//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) { if (*size==0) return -1; - int start = DetectASKClock(BinStream, *size, clk, 20); //clock default - if (*clk==0 || start < 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); + if (g_debugMode==2) prnt("DEBUG ASK: clk %d, beststart %d, amp %d", *clk, start, amp); uint8_t initLoopMax = 255; - if (initLoopMax > *size) initLoopMax=*size; + 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 -1; //just noise + return -2; //just noise + size_t errCnt = 0; // if clean clipped waves detected run alternate demod - if (DetectCleanAskWave(BinStream, *size, high, low)) - return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); + if (DetectCleanAskWave(BinStream, *size, high, low)) { + if (g_debugMode==2) prnt("DEBUG ASK: Clean Wave Detected - using clean wave demod"); + errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); + if (askType) //askman + return manrawdecode(BinStream, size, 0); + else //askraw + return errCnt; + } + if (g_debugMode==2) prnt("DEBUG ASK: Weak Wave Detected - using weak wave demod"); - int lastBit = 0; //set first clock check - can go negative - size_t i, iii = 0; - size_t errCnt = 0, bitnum = 0; //output counter + int lastBit; //set first clock check - can go negative + size_t i, bitnum = 0; //output counter uint8_t midBit = 0; - size_t bestStart = start, bestErrCnt = 0; //(*size/1000); - size_t MaxBits = 1024; - - //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance - if (!maxErr) initLoopMax = *clk * 2; - //if best start not already found by detectclock - if (start <= 0 || start > initLoopMax){ - bestErrCnt = maxErr+1; - //PrintAndLog("DEBUG - lastbit - %d",lastBit); - //loop to find first wave that works - for (iii=0; iii < initLoopMax; ++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 (i-lastBit > *clk && (BinStream[i] >= high || BinStream[i] <= low)){ - lastBit += *clk; - midBit = 0; - } else if (i-lastBit > (*clk/2) && midBit == 0) { - midBit = 1; - } else if ((i-lastBit) > *clk) { - //should have hit a high or low based on clock!! - //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 > maxErr) - break; - } - 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<=maxErr)) { - //possible good read - if (errCnt==0){ - bestStart=iii; - bestErrCnt=errCnt; - break; //great read - finish - } - if (errCnt maxErr){ - *invert = bestStart; - *clk = iii; - return -1; - } - //best run is good enough - set to best run and overwrite BinStream - lastBit = bestStart - *clk - 1; - errCnt = 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 = 3072; //max bits to collect + lastBit = start - *clk; - for (i = bestStart; i < *size; ++i) { - if (i - lastBit > *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 { + } else if (i-lastBit >= *clk+tol) { if (bitnum > 0) { - BinStream[bitnum++]=77; + if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i); + BinStream[bitnum++]=7; errCnt++; } + } else { //in tolerance - looking for peak + continue; } midBit = 0; lastBit += *clk; - } else if (i-lastBit > (*clk/2) && midBit == 0){ + } 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 { - + } else if (i-lastBit >= *clk/2+tol) { BinStream[bitnum] = BinStream[bitnum-1]; bitnum++; + } else { //in tolerance - looking for peak + continue; } midBit = 1; } @@ -485,6 +378,108 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max 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, uint8_t invert) +{ + 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 (bestErr>errCnt){ + bestErr=errCnt; + bestRun=ii; + } + errCnt=0; + } + //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; + } + if(bitnum>MaxBits) break; + } + *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 = 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) +{ + 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++]=7; + errCnt++; + } + if(bitnum>MaxBits) break; + } + *size=bitnum; + return errCnt; +} + +// by marshmellow // demod gProxIIDemod // error returns as -x // success returns start position in BitStream @@ -503,46 +498,62 @@ int gProxII_Demod(uint8_t BitStream[], size_t *size) //return start position return (int) startIdx; } - return -5; + return -5; //spacer bits not found - not a valid gproxII } -//translate wave to 11111100000 (1 for each short wave 0 for each long wave) +//translate wave to 11111100000 (1 for each short wave [higher freq] 0 for each long wave [lower freq]) size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) { 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; + if ( size < 1024 ) return 0; // not enough samples - // sync to first lo-hi transition, and threshold + //find start of modulating data in trace + idx = findModStart(dest, size, threshold_value, fchigh); // Need to threshold first sample - - if(dest[0] < threshold_value) dest[0] = 0; + if(dest[idx] < threshold_value) dest[0] = 0; else dest[0] = 1; - + idx++; + size_t numBits = 0; // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8) - // or 10 (fc/10) cycles but in practice due to noise etc we may end up with with anywhere + // or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10 - for(idx = 1; idx < size; idx++) { + // (could also be fc/5 && fc/7 for fsk1 = 4-9) + for(; idx < size-20; idx++) { // threshold current value if (dest[idx] < threshold_value) dest[idx] = 0; else dest[idx] = 1; // Check for 0->1 transition - if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition - if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise + if (dest[idx-1] < dest[idx]) { + preLastSample = LastSample; + LastSample = currSample; + currSample = idx-last_transition; + if (currSample < (fclow-2)) { //0-5 = garbage noise (or 0-3) //do nothing with extra garbage - } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves + } else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves (or 3-6 = 5) + //correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5) + if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1))){ + dest[numBits-1]=1; + } + dest[numBits++]=1; + + } else if (currSample > (fchigh+1) && numBits < 3) { //12 + and first two bit = unusable garbage + //do nothing with beginning garbage and reset.. should be rare.. + numBits = 0; + } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's (or 4 then a 6 should be two 5's) dest[numBits++]=1; - } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage - //do nothing with beginning garbage - } else { //9+ = 10 waves + } else { //9+ = 10 sample waves (or 6+ = 7) dest[numBits++]=0; } last_transition = idx; @@ -552,6 +563,7 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow } //translate 11111100000 to 10 +//rfLen = clock, fchigh = larger field clock, fclow = smaller field clock size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) { @@ -561,27 +573,18 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint32_t n=1; for( idx=1; idx < size; idx++) { n++; - if (dest[idx]==lastval) continue; + if (dest[idx]==lastval) continue; //skip until we hit a transition + //find out how many bits (n) we collected //if lastval was 1, we have a 1->0 crossing 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; + //add to our destination the bits we collected memset(dest+numBits, dest[idx-1]^invert , n); numBits += n; n=0; @@ -599,6 +602,7 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, } return numBits; } + //by marshmellow (from holiman's base) // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod) int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) @@ -673,17 +677,6 @@ 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 num = 0; - for(int i = 0 ; i < numbits ; i++) - { - num = (num << 1) | (*src); - src++; - } - return num; -} - int IOdemodFSK(uint8_t *dest, size_t size) { if (justNoise(dest, size)) return -1; @@ -712,29 +705,53 @@ int IOdemodFSK(uint8_t *dest, size_t size) return (int) startIdx; } return -5; -} +} // 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) -size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) +// find viking preamble 0xF200 in already demoded data +int VikingDemod_AM(uint8_t *dest, size_t *size) { + //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 + uint32_t checkCalc = bytebits_to_byte(dest+startIdx,8) ^ bytebits_to_byte(dest+startIdx+8,8) ^ bytebits_to_byte(dest+startIdx+16,8) + ^ bytebits_to_byte(dest+startIdx+24,8) ^ bytebits_to_byte(dest+startIdx+32,8) ^ bytebits_to_byte(dest+startIdx+40,8) + ^ bytebits_to_byte(dest+startIdx+48,8) ^ bytebits_to_byte(dest+startIdx+56,8); + if ( checkCalc != 0xA8 ) return -5; + if (*size != 64) return -6; + //return start position + return (int) startIdx; +} + +// find presco preamble 0x10D in already demoded data +int PrescoDemod(uint8_t *dest, size_t *size) { + //make sure buffer has data + if (*size < 64*2) return -2; + + size_t startIdx = 0; + uint8_t preamble[] = {1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -4; //preamble not found + //return start position + return (int) startIdx; +} + +// 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) { - uint32_t parityWd = 0; - size_t j = 0, bitCnt = 0; - 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]); - } - j--; - // if parity fails then return 0 - if (parityTest(parityWd, pLen, pType) == 0) return -1; - bitCnt+=(pLen-1); - parityWd = 0; - } - // if we got here then all the parities passed - //return ID start index and size - return bitCnt; + //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 @@ -759,7 +776,7 @@ int AWIDdemodFSK(uint8_t *dest, size_t *size) } // by marshmellow -// FSK Demod then try to locate an Farpointe Data (pyramid) ID +// FSK Demod then try to locate a Farpointe Data (pyramid) ID int PyramiddemodFSK(uint8_t *dest, size_t *size) { //make sure buffer has data @@ -780,74 +797,61 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size) return (int)startIdx; } - -uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low) +// 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; + bool allArePeaks = true; uint16_t cntPeaks=0; - size_t loopEnd = 572; + size_t loopEnd = 512+160; if (loopEnd > size) loopEnd = size; - for (size_t i=60; ilow && dest[i] 300) return 1; + if (!allArePeaks){ + if (cntPeaks > 300) return true; } - return allPeaks; + return allArePeaks; } - // by marshmellow // to help detect clocks on heavily clipped samples -// based on counts between zero crossings -int DetectStrongAskClock(uint8_t dest[], size_t size) +// based on count of low to low +int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low) { - int clk[]={0,8,16,32,40,50,64,100,128}; - 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 fndClk[] = {8,16,32,40,50,64,128}; + size_t startwave; + size_t i = 100; + 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; } - 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]; + // set clock + if (g_debugMode==2) prnt("DEBUG ASK: detectstrongASKclk smallest wave: %d",minClk); + for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { + if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) + return fndClk[clkCnt]; } - return -1; + return 0; } // by marshmellow @@ -856,26 +860,34 @@ int DetectStrongAskClock(uint8_t dest[], size_t size) // 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=0; - uint8_t clk[]={8,16,32,40,50,64,100,128,255}; + 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 quit - - for (;i<8;++i) - if (clk[i] == *clock) return 0; + if (size <= loopCnt+60) return -1; //not enough samples + size -= 60; //sometimes there is a strange end wave - filter out this.... + //if we already have a valid clock + uint8_t clockFnd=0; + for (;i0; i--){ - if (clk[i] == ans) { - *clock = ans; - return 0; + if (!clockFnd){ + if (DetectCleanAskWave(dest, size, peak, low)==1){ + int ans = DetectStrongAskClock(dest, size, peak, low); + if (g_debugMode==2) prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %d",ans); + for (i=clkEnd-1; i>0; 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] + } } } } @@ -885,16 +897,24 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) 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=0; clkCnt < 8; clkCnt++){ - if (clk[clkCnt] == 32){ + for(; clkCnt < clkEnd; clkCnt++){ + if (clk[clkCnt] <= 32){ tol=1; }else{ tol=0; } - if (!maxErr) loopCnt=clk[clkCnt]*2; + //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 256) + //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; @@ -910,11 +930,11 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) errCnt++; } } - //if we found no errors then we can stop here + //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<6) { - *clock = clk[clkCnt]; + if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %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 @@ -924,9 +944,9 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) } } } - uint8_t iii=0; + uint8_t iii; uint8_t best=0; - for (iii=0; iii<8; ++iii){ + for (iii=1; iii maxErr) return -1; - *clock = clk[best]; + if (!clockFnd) *clock = clk[best]; return bestStart[best]; } @@ -948,7 +968,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock) uint8_t clk[]={255,16,32,40,50,64,100,128,255}; //255 is not a valid clock uint16_t loopCnt = 4096; //don't need to loop through entire array... if (size == 0) return 0; - if (size= dest[i+2]){ if (waveStart == 0) { waveStart = i+1; - //PrintAndLog("DEBUG: waveStart: %d",waveStart); + //prnt("DEBUG: waveStart: %d",waveStart); } else { waveEnd = i+1; - //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); + //prnt("DEBUG: waveEnd: %d",waveEnd); waveLenCnt = waveEnd-waveStart; if (waveLenCnt > fc){ firstFullWave = waveStart; @@ -983,7 +1003,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock) } } } - //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); + if (g_debugMode ==2) prnt("DEBUG PSK: 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--){ @@ -991,7 +1011,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock) waveStart = 0; errCnt=0; peakcnt=0; - //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit); + if (g_debugMode == 2) prnt("DEBUG PSK: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit); for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){ //top edge of wave = start of new wave @@ -1004,7 +1024,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock) 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 (g_debugMode == 2) prnt("DEBUG PSK: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+clk[clkCnt]-tol,i+1,fc); if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit peakcnt++; lastClkBit+=clk[clkCnt]; @@ -1033,11 +1053,40 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock) 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]); + if (g_debugMode == 2) prnt("DEBUG PSK: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[i],peaksdet[i],bestErr[i],clk[best]); } return clk[best]; } +int DetectStrongNRZClk(uint8_t *dest, size_t size, int peak, int low){ + //find shortest transition from high to low + size_t i = 0; + size_t transition1 = 0; + int lowestTransition = 255; + bool lastWasHigh = false; + + //find first valid beginning of a high or low wave + while ((dest[i] >= peak || dest[i] <= low) && (i < size)) + ++i; + while ((dest[i] < peak && dest[i] > low) && (i < size)) + ++i; + lastWasHigh = (dest[i] >= peak); + + if (i==size) return 0; + transition1 = i; + + for (;i < size; i++) { + if ((dest[i] >= peak && !lastWasHigh) || (dest[i] <= low && lastWasHigh)) { + lastWasHigh = (dest[i] >= peak); + if (i-transition1 < lowestTransition) lowestTransition = i-transition1; + transition1 = i; + } + } + if (lowestTransition == 255) lowestTransition = 0; + if (g_debugMode==2) prnt("DEBUG NRZ: detectstrongNRZclk smallest wave: %d",lowestTransition); + return lowestTransition; +} + //by marshmellow //detect nrz clock by reading #peaks vs no peaks(or errors) int DetectNRZClock(uint8_t dest[], size_t size, int clock) @@ -1046,8 +1095,7 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock) 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++; + if (!firstpeak) continue; + smplCnt++; } else { - if (peakcnt>0 && maxPeak < peakcnt){ - maxPeak = peakcnt; + firstpeak=true; + if (smplCnt > 6 ){ + if (maxPeak > smplCnt){ + maxPeak = smplCnt; + //prnt("maxPk: %d",maxPeak); + } + peakcnt++; + //prnt("maxPk: %d, smplCnt: %d, peakcnt: %d",maxPeak,smplCnt,peakcnt); + smplCnt=0; } - peakcnt=0; } } + bool errBitHigh = 0; + bool bitHigh = 0; + uint8_t ignoreCnt = 0; + uint8_t ignoreWindow = 4; + bool lastPeakHigh = 0; + int lastBit = 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++; + peakcnt = 0; + bitHigh = false; + ignoreCnt = 0; + lastBit = ii-clk[clkCnt]; + //loop through to see if this start location works + for (i = ii; i < size-20; ++i) { + //if we are at a clock bit + if ((i >= lastBit + clk[clkCnt] - tol) && (i <= lastBit + clk[clkCnt] + tol)) { + //test high/low + if (dest[i] >= peak || dest[i] <= low) { + //if same peak don't count it + if ((dest[i] >= peak && !lastPeakHigh) || (dest[i] <= low && lastPeakHigh)) { + peakcnt++; + } + lastPeakHigh = (dest[i] >= peak); + bitHigh = true; + errBitHigh = false; + ignoreCnt = ignoreWindow; + lastBit += clk[clkCnt]; + } else if (i == lastBit + clk[clkCnt] + tol) { + lastBit += clk[clkCnt]; + } + //else if not a clock bit and no peaks + } else if (dest[i] < peak && dest[i] > low){ + if (ignoreCnt==0){ + bitHigh=false; + if (errBitHigh==true) peakcnt--; + errBitHigh=false; + } else { + ignoreCnt--; + } + // else if not a clock bit but we have a peak + } else if ((dest[i]>=peak || dest[i]<=low) && (!bitHigh)) { + //error bar found no clock... + errBitHigh=true; } } if(peakcnt>peaksdet[clkCnt]) { @@ -1099,11 +1191,16 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock) int iii=7; uint8_t best=0; for (iii=7; iii > 0; iii--){ - if (peaksdet[iii] > peaksdet[best]){ + if ((peaksdet[iii] >= (peaksdet[best]-1)) && (peaksdet[iii] <= peaksdet[best]+1) && lowestTransition) { + if (clk[iii] > (lowestTransition - (clk[iii]/8)) && clk[iii] < (lowestTransition + (clk[iii]/8))) { + best = iii; + } + } else 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]); + if (g_debugMode==2) prnt("DEBUG NRZ: Clk: %d, peaks: %d, maxPeak: %d, bestClk: %d, lowestTrs: %d",clk[iii],peaksdet[iii],maxPeak, clk[best], lowestTransition); } + return clk[best]; } @@ -1115,7 +1212,7 @@ void psk1TOpsk2(uint8_t *BitStream, size_t size) size_t i=1; uint8_t lastBit=BitStream[0]; for (; i*size) gLen = *size; + if (gLen>*size) gLen = *size-20; 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 - 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 - 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 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 (ignoreCnt==0){ - bitHigh=0; - if (errBitHigh==1) errCnt++; - errBitHigh=0; - } else { - ignoreCnt--; - } - } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) { - //error bar found no clock... - errBitHigh=1; - } - if (((i-iii) / *clk)>=MaxBits) break; - } - //we got more than 64 good bits and not all errors - if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) { - //possible good read - if (!errCnt || peakCnt > bestPeakCnt){ - bestFirstPeakHigh=firstPeakHigh; - bestErrCnt = errCnt; - bestPeakCnt = peakCnt; - bestPeakStart = iii; - if (!errCnt) break; //great read - finish - } - } - } + + uint8_t bit=0; + //convert wave samples to 1's and 0's + for(i=20; i < *size-20; i++){ + if (dest[i] >= high) bit = 1; + if (dest[i] <= low) bit = 0; + dest[i] = bit; } - //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++] = 77; - errCnt++; - } - errBitHigh=0; - } else { - ignoreCnt--; - } - } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) { - //error bar found no clock... - errBitHigh=1; + //now demod based on clock (rf/32 = 32 1's for one 1 bit, 32 0's for one 0 bit) + size_t lastBit = 0; + size_t numBits = 0; + for(i=21; i < *size-20; i++) { + //if transition detected or large number of same bits - store the passed bits + if (dest[i] != dest[i-1] || (i-lastBit) == (10 * *clk)) { + memset(dest+numBits, dest[i-1] ^ *invert, (i - lastBit + (*clk/4)) / *clk); + numBits += (i - lastBit + (*clk/4)) / *clk; + lastBit = i-1; } - if (bitnum >= MaxBits) break; } - *size = bitnum; - return bestErrCnt; + *size = numBits; + return 0; } //by marshmellow @@ -1340,18 +1308,18 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc size_t i; if (size == 0) return 0; - uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); + uint8_t fcTol = ((fcHigh*100 - fcLow*100)/2 + 50)/100; //(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++) + // prime i to first peak / up transition + for (i = 160; i < size-20; i++) if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) break; - for (; i < size-1; i++){ + for (; i < size-20; i++){ fcCounter++; rfCounter++; @@ -1359,7 +1327,10 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc continue; // else new peak // if we got less than the small fc + tolerance then set it to the small fc - if (fcCounter < fcLow+fcTol) + // if it is inbetween set it to the last counter + if (fcCounter < fcHigh && fcCounter > fcLow) + fcCounter = lastFCcnt; + else if (fcCounter < fcLow+fcTol) fcCounter = fcLow; else //set it to the large fc fcCounter = fcHigh; @@ -1369,7 +1340,7 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc //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){ + if (rfLens[ii] >= (rfCounter-4) && rfLens[ii] <= (rfCounter+4)){ rfCnts[ii]++; rfCounter = 0; break; @@ -1391,7 +1362,6 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc 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; @@ -1403,27 +1373,30 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc } else if(rfCnts[i]>rfCnts[rfHighest3]){ rfHighest3=i; } + if (g_debugMode==2) prnt("DEBUG FSK: RF %d, cnts %d",rfLens[i], rfCnts[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]); + if (g_debugMode==2) prnt("DEBUG FSK: most counted rf values: 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 + // test 128 down to 32 (shouldn't be possible to have fc/10 & fc/8 and rf/16 or less) int ii=7; - for (; ii>=0; ii--){ + for (; ii>=2; 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){ + if (g_debugMode==2) prnt("DEBUG FSK: clk %d divides into the 3 most rf values within tolerance",clk[ii]); break; } } } } - if (ii<0) return 0; // oops we went too far + if (ii<2) return 0; // oops we went too far return clk[ii]; } @@ -1434,20 +1407,20 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc //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 fcLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; uint8_t fcLensFnd = 0; - uint8_t lastFCcnt=0; + uint8_t lastFCcnt = 0; uint8_t fcCounter = 0; size_t i; - if (size == 0) return 0; + if (size < 180) return 0; // prime i to first up transition - for (i = 1; i < size-1; i++) + for (i = 160; i < size-20; i++) if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) break; - for (; i < size-1; i++){ + for (; i < size-20; i++){ if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ // new up transition fcCounter++; @@ -1460,14 +1433,14 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) lastFCcnt = fcCounter; } // find which fcLens to save it to: - for (int ii=0; ii<10; ii++){ + for (int ii=0; ii<15; ii++){ if (fcLens[ii]==fcCounter){ fcCnts[ii]++; fcCounter=0; break; } } - if (fcCounter>0 && fcLensFnd<10){ + if (fcCounter>0 && fcLensFnd<15){ //add new fc length fcCnts[fcLensFnd]++; fcLens[fcLensFnd++]=fcCounter; @@ -1479,11 +1452,10 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) } } - uint8_t best1=9, best2=9, best3=9; + uint8_t best1=14, best2=14, best3=14; 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); + for (i=0; i<15; i++){ // get the 3 best FC values if (fcCnts[i]>maxCnt1) { best3=best2; @@ -1496,7 +1468,9 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) } else if(fcCnts[i]>fcCnts[best3]){ best3=i; } + if (g_debugMode==2) prnt("DEBUG countfc: FC %u, Cnt %u, best fc: %u, best2 fc: %u",fcLens[i],fcCnts[i],fcLens[best1],fcLens[best2]); } + if (fcLens[best1]==0) return 0; uint8_t fcH=0, fcL=0; if (fcLens[best1]>fcLens[best2]){ fcH=fcLens[best1]; @@ -1505,11 +1479,13 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) fcH=fcLens[best2]; fcL=fcLens[best1]; } - + if ((size-180)/fcH/3 > fcCnts[best1]+fcCnts[best2]) { + if (g_debugMode==2) prnt("DEBUG countfc: fc is too large: %u > %u. Not psk or fsk",(size-180)/fcH/3,fcCnts[best1]+fcCnts[best2]); + return 0; //lots of waves not psk or fsk + } // 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]; } @@ -1522,28 +1498,39 @@ 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> 8; + if (fc2 == 10) return -1; //fsk found - quit + fc = fc & 0xFF; if (fc!=2 && fc!=4 && fc!=8) return -1; //PrintAndLog("DEBUG: FC: %d",fc); *clock = DetectPSKClock(dest, *size, *clock); if (*clock == 0) return -1; - int avgWaveVal=0, lastAvgWaveVal=0; + + //find start of modulating data in trace + uint8_t threshold_value = 123; //-5 + i = findModStart(dest, *size, threshold_value, fc); + //find first phase shift - for (i=0; i= dest[i+2]){ waveEnd = i+1; - //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); + if (g_debugMode == 2) prnt("DEBUG PSK: waveEnd: %u, waveStart: %u",waveEnd, waveStart); waveLenCnt = waveEnd-waveStart; - if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave + if (waveLenCnt > fc && waveStart > fc && !(waveLenCnt > fc+3)){ //not first peak and is a large wave but not out of whack 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 + //if average wave value is > graph 0 then it is an up wave or a 1 (could cause inverting) + if (lastAvgWaveVal > threshold_value) curPhase ^= 1; break; } waveStart = i+1; @@ -1551,14 +1538,21 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) } 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); + if (firstFullWave == 0) { + // no phase shift detected - could be all 1's or 0's - doesn't matter where we start + // so skip a little to ensure we are past any Start Signal + firstFullWave = 160; + memset(dest, curPhase, firstFullWave / *clock); + } else { + memset(dest, curPhase^1, firstFullWave / *clock); + } + //advance bits numBits += (firstFullWave / *clock); + //set start of wave as clock align + lastClkBit = firstFullWave; + if (g_debugMode==2) prnt("DEBUG PSK: firstFullWave: %u, waveLen: %u",firstFullWave,fullWaveLen); + if (g_debugMode==2) prnt("DEBUG PSK: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc); + waveStart = 0; dest[numBits++] = curPhase; //set first read bit for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){ //top edge of wave = start of new wave @@ -1583,11 +1577,14 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) //noise after a phase shift - ignore } else { //phase shift before supposed to based on clock errCnt++; - dest[numBits++] = 77; + dest[numBits++] = 7; } } else if (i+1 > lastClkBit + *clock + tol + fc){ lastClkBit += *clock; //no phase shift but clock bit dest[numBits++] = curPhase; + } else if (waveLenCnt < fc - 1) { //wave is smaller than field clock (shouldn't happen often) + errCnt2++; + if(errCnt2 > 101) return errCnt2; } avgWaveVal = 0; waveStart = i+1; @@ -1598,3 +1595,198 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) *size = numBits; return errCnt; } + +bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { + size_t ststart = 0, stend = 0; + return DetectST_ext(buffer, size, foundclock, &ststart, &stend); +} + +//by marshmellow +//attempt to identify a Sequence Terminator in ASK modulated raw wave +bool DetectST_ext(uint8_t buffer[], size_t *size, int *foundclock, size_t *ststart, size_t *stend) { + size_t bufsize = *size; + //need to loop through all samples and identify our clock, look for the ST pattern + uint8_t fndClk[] = {8,16,32,40,50,64,128}; + int clk = 0; + int tol = 0; + int i, j, skip, start, end, low, high, minClk, waveStart; + bool complete = false; + int tmpbuff[bufsize / 32]; //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured + int waveLen[bufsize / 32]; // if clock is larger then we waste memory in array size that is not needed... + size_t testsize = (bufsize < 512) ? bufsize : 512; + int phaseoff = 0; + high = low = 128; + memset(tmpbuff, 0, sizeof(tmpbuff)); + + if ( getHiLo(buffer, testsize, &high, &low, 80, 80) == -1 ) { + if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting"); + return false; //just noise + } + i = 0; + j = 0; + minClk = 255; + // get to first full low to prime loop and skip incomplete first pulse + while ((buffer[i] < high) && (i < bufsize)) + ++i; + while ((buffer[i] > low) && (i < bufsize)) + ++i; + skip = i; + + // populate tmpbuff buffer with pulse lengths + while (i < bufsize) { + // measure from low to low + while ((buffer[i] > low) && (i < bufsize)) + ++i; + start= i; + while ((buffer[i] < high) && (i < bufsize)) + ++i; + //first high point for this wave + waveStart = i; + while ((buffer[i] > low) && (i < bufsize)) + ++i; + if (j >= (bufsize/32)) { + break; + } + waveLen[j] = i - waveStart; //first high to first low + tmpbuff[j++] = i - start; + if (i-start < minClk && i < bufsize) { + minClk = i - start; + } + } + // set clock - might be able to get this externally and remove this work... + if (!clk) { + for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { + tol = fndClk[clkCnt]/8; + if (minClk >= fndClk[clkCnt]-tol && minClk <= fndClk[clkCnt]+1) { + clk=fndClk[clkCnt]; + break; + } + } + // clock not found - ERROR + if (!clk) { + if (g_debugMode==2) prnt("DEBUG STT: clock not found - quitting"); + return false; + } + } else tol = clk/8; + + *foundclock = clk; + + // look for Sequence Terminator - should be pulses of clk*(1 or 1.5), clk*2, clk*(1.5 or 2) + start = -1; + for (i = 0; i < j - 4; ++i) { + skip += tmpbuff[i]; + if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior + if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol && waveLen[i+1] > clk*3/2-tol) { //2 clocks and wave size is 1 1/2 + if (tmpbuff[i+2] >= (clk*3)/2-tol && tmpbuff[i+2] <= clk*2+tol && waveLen[i+2] > clk-tol) { //1 1/2 to 2 clocks and at least one full clock wave + if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit + start = i + 3; + break; + } + } + } + } + } + // first ST not found - ERROR + if (start < 0) { + if (g_debugMode==2) prnt("DEBUG STT: first STT not found - quitting"); + return false; + } else { + if (g_debugMode==2) prnt("DEBUG STT: first STT found at: %d, j=%d",start, j); + } + if (waveLen[i+2] > clk*1+tol) + phaseoff = 0; + else + phaseoff = clk/2; + + // skip over the remainder of ST + skip += clk*7/2; //3.5 clocks from tmpbuff[i] = end of st - also aligns for ending point + + // now do it again to find the end + end = skip; + for (i += 3; i < j - 4; ++i) { + end += tmpbuff[i]; + if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior + if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol && waveLen[i+1] > clk*3/2-tol) { //2 clocks and wave size is 1 1/2 + if (tmpbuff[i+2] >= (clk*3)/2-tol && tmpbuff[i+2] <= clk*2+tol && waveLen[i+2] > clk-tol) { //1 1/2 to 2 clocks and at least one full clock wave + if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit + complete = true; + break; + } + } + } + } + } + end -= phaseoff; + //didn't find second ST - ERROR + if (!complete) { + if (g_debugMode==2) prnt("DEBUG STT: second STT not found - quitting"); + return false; + } + if (g_debugMode==2) prnt("DEBUG STT: start of data: %d end of data: %d, datalen: %d, clk: %d, bits: %d, phaseoff: %d", skip, end, end-skip, clk, (end-skip)/clk, phaseoff); + //now begin to trim out ST so we can use normal demod cmds + start = skip; + size_t datalen = end - start; + // check validity of datalen (should be even clock increments) - use a tolerance of up to 1/8th a clock + if ( clk - (datalen % clk) <= clk/8) { + // padd the amount off - could be problematic... but shouldn't happen often + datalen += clk - (datalen % clk); + } else if ( (datalen % clk) <= clk/8 ) { + // padd the amount off - could be problematic... but shouldn't happen often + datalen -= datalen % clk; + } else { + if (g_debugMode==2) prnt("DEBUG STT: datalen not divisible by clk: %u %% %d = %d - quitting", datalen, clk, datalen % clk); + return false; + } + // if datalen is less than one t55xx block - ERROR + if (datalen/clk < 8*4) { + if (g_debugMode==2) prnt("DEBUG STT: datalen is less than 1 full t55xx block - quitting"); + return false; + } + size_t dataloc = start; + if (buffer[dataloc-(clk*4)-(clk/8)] <= low && buffer[dataloc] <= low && buffer[dataloc-(clk*4)] >= high) { + //we have low drift (and a low just before the ST and a low just after the ST) - compensate by backing up the start + for ( i=0; i <= (clk/8); ++i ) { + if ( buffer[dataloc - (clk*4) - i] <= low ) { + dataloc -= i; + break; + } + } + } + + size_t newloc = 0; + i=0; + if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen); + bool firstrun = true; + // warning - overwriting buffer given with raw wave data with ST removed... + while ( dataloc < bufsize-(clk/2) ) { + //compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part) + if (buffer[dataloc]low && buffer[dataloc+3]low) { + for(i=0; i < clk/2-tol; ++i) { + buffer[dataloc+i] = high+5; + } + } //test for single sample outlier (high between two lows) in the case of very strong waves + if (buffer[dataloc] >= high && buffer[dataloc+2] <= low) { + buffer[dataloc] = buffer[dataloc+2]; + buffer[dataloc+1] = buffer[dataloc+2]; + } + if (firstrun) { + *stend = dataloc; + *ststart = dataloc-(clk*4); + firstrun=false; + } + for (i=0; i