X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/f0cf62cd734219c2f8b012a4e3ba42520344bce4..385f398740895f512abc90ea5a00a9be82bf115b:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 873b6305..88a250d8 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -1,286 +1,325 @@ //----------------------------------------------------------------------------- -// Copyright (C) 2014 +// Copyright (C) 2014 // // This code is licensed to you under the terms of the GNU GPL, version 2 or, // at your option, any later version. See the LICENSE.txt file for the text of // the license. //----------------------------------------------------------------------------- -// Low frequency commands +// Low frequency demod/decode commands //----------------------------------------------------------------------------- -#include #include #include #include "lfdemod.h" + +uint8_t justNoise(uint8_t *BitStream, size_t size) +{ + static const uint8_t THRESHOLD = 123; + //test samples are not just noise + uint8_t justNoise1 = 1; + for(size_t idx=0; idx < size && justNoise1 ;idx++){ + justNoise1 = BitStream[idx] < THRESHOLD; + } + return justNoise1; +} + //by marshmellow -//takes 1s and 0s and searches for EM410x format - output EM ID -uint64_t Em410xDecode(uint8_t *BitStream, uint32_t BitLen) +//get high and low 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) { - //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 - int high = 0, low = 128; - uint64_t lo = 0; - uint32_t i = 0; - uint32_t initLoopMax = 65; - - if (initLoopMax > BitLen) - initLoopMax = BitLen; - - for (; i < initLoopMax; ++i) //65 samples should be plenty to find high and low values - { - if (BitStream[i] > high) - high = BitStream[i]; - else if (BitStream[i] < low) - low = BitStream[i]; + *high=0; + *low=255; + // get high and low thresholds + for (int i=0; i < size; i++){ + if (BitStream[i] > *high) *high = BitStream[i]; + if (BitStream[i] < *low) *low = BitStream[i]; } + if (*high < 123) return -1; // just noise + *high = (int)(((*high-128)*(((float)fuzzHi)/100))+128); + *low = (int)(((*low-128)*(((float)fuzzLo)/100))+128); + return 1; +} - if (((high !=1)||(low !=0))){ //allow only 1s and 0s - return 0; +// by marshmellow +// pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType +// returns 1 if passed +uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) +{ + uint8_t ans = 0; + for (uint8_t i = 0; i < bitLen; i++){ + ans ^= ((bits >> i) & 1); } + //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); + return (ans == pType); +} - uint8_t parityTest = 0; - // 111111111 bit pattern represent start of frame - uint8_t frame_marker_mask[] = {1,1,1,1,1,1,1,1,1}; - uint32_t idx = 0; - uint32_t j = 0; - uint8_t resetCnt = 0; - while( (idx + 64) < BitLen) { - - restart: - - // search for a start of frame marker - if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) { - // frame marker found - idx += 9;//sizeof(frame_marker_mask); - for ( i = 0; i < 10; ++i){ - for( j = 0; j < 5; ++j){ - parityTest += BitStream[(i*5) + j + idx]; - } - if (parityTest == ( (parityTest >> 1) << 1)){ - parityTest = 0; - for (j = 0; j < 4; ++j){ - lo = ( lo << 1LL)|( BitStream[( i * 5 ) + j + idx]); - } - } else { - //parity failed - parityTest = 0; - idx -= 8; - if (resetCnt > 5) return 0; - resetCnt++; - goto restart;//continue; - } - } - //skip last 5 bit parity test for simplicity. - return lo; - } else { - idx++; - } - } - return 0; +//by marshmellow +//search for given preamble in given BitStream and return startIndex and length +uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx) +{ + uint8_t foundCnt=0; + for (int idx=0; idx < *size - pLen; idx++){ + if (memcmp(BitStream+idx, preamble, pLen) == 0){ + //first index found + foundCnt++; + if (foundCnt == 1){ + *startIdx = idx; + } + if (foundCnt == 2){ + *size = idx - *startIdx; + return 1; + } + } + } + return 0; +} + + +//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) +{ + //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future + // otherwise could be a void with no arguments + //set defaults + uint64_t lo=0; + uint32_t i = 0; + if (BitStream[1]>1){ //allow only 1s and 0s + // PrintAndLog("no data found"); + return 0; + } + // 111111111 bit pattern represent start of frame + uint8_t preamble[] = {1,1,1,1,1,1,1,1,1}; + uint32_t idx = 0; + uint32_t parityBits = 0; + uint8_t errChk = 0; + *startIdx = 0; + for (uint8_t extraBitChk=0; extraBitChk<5; extraBitChk++){ + errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx); + if (errChk == 0) return 0; + idx = *startIdx + 9; + for (i=0; i<10;i++){ //loop through 10 sets of 5 bits (50-10p = 40 bits) + parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5); + //check even parity + if (parityTest(parityBits, 5, 0) == 0){ + //parity failed try next bit (in the case of 1111111111) but last 9 = preamble + startIdx++; + errChk = 0; + break; + } + for (uint8_t ii=0; ii<4; ii++){ + lo = (lo << 1LL) | (BitStream[(i*5)+ii+idx]); + } + } + if (errChk != 0) return lo; + //skip last 5 bit parity test for simplicity. + // *size = 64; + } + return 0; } //by marshmellow //takes 2 arguments - clock and invert both as integers -//attempts to demodulate ask while decoding manchester +//attempts to demodulate ask while decoding manchester //prints binary found and saves in graphbuffer for further commands -int askmandemod(uint8_t *BinStream, uint32_t *BitLen, int *clk, int *invert) +int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) { int i; - int high = 0, low = 128; - *clk = DetectASKClock(BinStream, (size_t)*BitLen, *clk); //clock default - - if (*clk < 8 ) *clk = 64; - if (*clk < 32 ) *clk = 32; - if (*invert != 1) *invert = 0; - - uint32_t initLoopMax = 200; - if (initLoopMax > *BitLen) - initLoopMax = *BitLen; - - // Detect high and lows - // 200 samples should be enough to find high and low values - for (i = 0; i < initLoopMax; ++i) { - if (BinStream[i] > high) - high = BinStream[i]; - else if (BinStream[i] < low) - low = BinStream[i]; - } - - //throw away static - if ((high < 158) ) - return -2; + int clk2=*clk; + *clk=DetectASKClock(BinStream, *size, *clk); //clock default - //25% fuzz in case highs and lows aren't clipped [marshmellow] - high = (int)(high * .75); - low = (int)(low+128 * .25); - - int lastBit = 0; // set first clock check - uint32_t bitnum = 0; // output counter + // if autodetected too low then adjust //MAY NEED ADJUSTMENT + if (clk2==0 && *clk<8) *clk =64; + if (clk2==0 && *clk<32) *clk=32; + if (*invert != 0 && *invert != 1) *invert=0; + uint32_t initLoopMax = 200; + if (initLoopMax > *size) initLoopMax=*size; + // Detect high and lows + // 25% fuzz in case highs and lows aren't clipped [marshmellow] + int high, low, ans; + ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); + if (ans<1) return -2; //just noise - // clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - int tol = ( *clk == 32 ) ? 1 : 0; + // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); + int lastBit = 0; //set first clock check + uint32_t bitnum = 0; //output counter + int tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave + if (*clk<=32)tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely + int iii = 0; + uint32_t gLen = *size; + if (gLen > 3000) gLen=3000; + uint8_t errCnt =0; + uint32_t bestStart = *size; + uint32_t bestErrCnt = (*size/1000); + uint32_t maxErr = (*size/1000); + // PrintAndLog("DEBUG - lastbit - %d",lastBit); + // loop to find first wave that works + for (iii=0; iii < gLen; ++iii){ + if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){ + lastBit=iii-*clk; + errCnt=0; + // loop through to see if this start location works + for (i = iii; i < *size; ++i) { + if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ + lastBit+=*clk; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! - int j = 0; - uint32_t gLen = *BitLen; + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (gLen > 3000) gLen = 3000; + errCnt++; + lastBit+=*clk;//skip over until hit too many errors + if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over + } + } + if ((i-iii) >(400 * *clk)) break; //got plenty of bits + } + //we got more than 64 good bits and not all errors + if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt= high) && ((i-lastBit) > (*clk-tol))){ + lastBit += *clk; + BinStream[bitnum] = *invert; + bitnum++; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + BinStream[bitnum] = 1-*invert; + bitnum++; + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! - uint8_t errCnt = 0; - uint32_t bestStart = *BitLen; - uint32_t bestErrCnt = (*BitLen/1000); - uint32_t maxErr = bestErrCnt; + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + if (bitnum > 0){ + BinStream[bitnum]=77; + bitnum++; + } - //loop to find first wave that works - for (j=0; j < gLen; ++j){ - - if ((BinStream[j] >= high)||(BinStream[j] <= low)){ - lastBit = j - *clk; - errCnt = 0; - - //loop through to see if this start location works - for (i = j; i < *BitLen; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit += *clk; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit += *clk; - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit) > (*clk + tol)){ - //should have hit a high or low based on clock!! - - errCnt++; - lastBit += *clk;//skip over until hit too many errors - if (errCnt > maxErr) break; //allow 1 error for every 1000 samples else start over - } - } - if ((i-j) >(400 * *clk)) break; //got plenty of bits - } - //we got more than 64 good bits and not all errors - if ((((i-j)/ *clk) > (64 + errCnt)) && (errCnt < maxErr)) { - //possible good read - if (errCnt == 0){ - bestStart = j; - bestErrCnt = errCnt; - break; //great read - finish - } - if (errCnt < bestErrCnt){ //set this as new best run - bestErrCnt = errCnt; - bestStart = j; - } - } - } - } - if (bestErrCnt < maxErr){ - //best run is good enough set to best run and set overwrite BinStream - j = bestStart; - lastBit = bestStart - *clk; - bitnum = 0; - for (i = j; i < *BitLen; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit += *clk; - BinStream[bitnum] = *invert; - bitnum++; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit += *clk; - BinStream[bitnum] = 1 - *invert; - bitnum++; - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit) > (*clk+tol)){ - //should have hit a high or low based on clock!! - if (bitnum > 0){ - BinStream[bitnum] = 77; - bitnum++; + lastBit+=*clk;//skip over error } - lastBit += *clk;//skip over error } + if (bitnum >=400) break; } - if (bitnum >= 400) break; - } - *BitLen = bitnum; - } else { - *invert = bestStart; - *clk = j; - return -1; - } - return bestErrCnt; + *size=bitnum; + } else{ + *invert=bestStart; + *clk=iii; + return -1; + } + return bestErrCnt; +} + +//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 10 and 01 and manchester decode //run through 2 times and take least errCnt -int manrawdecode(uint8_t * bits, int *bitlen) +int manrawdecode(uint8_t * BitStream, size_t *size) { - int bitnum = 0; - int errCnt = 0; - int bestErr = 1000; - int bestRun = 0; - int i = 1; - int j = 1; - - for (; j < 3; ++j){ - i = 1; - for ( i = i + j; i < *bitlen-2; i += 2){ - if ( bits[i]==1 && (bits[i+1]==0)){ - } else if ((bits[i]==0)&& bits[i+1]==1){ + int bitnum=0; + int errCnt =0; + int i=1; + int bestErr = 1000; + int bestRun = 0; + int ii=1; + for (ii=1;ii<3;++ii){ + i=1; + for (i=i+ii;i<*size-2;i+=2){ + if(BitStream[i]==1 && (BitStream[i+1]==0)){ + } else if((BitStream[i]==0)&& BitStream[i+1]==1){ } else { errCnt++; } - if(bitnum > 300) break; + if(bitnum>300) break; } - if (bestErr > errCnt){ - bestErr = errCnt; - bestRun = j; - } - errCnt = 0; + if (bestErr>errCnt){ + bestErr=errCnt; + bestRun=ii; + } + errCnt=0; } - errCnt = bestErr; - if (errCnt < 20){ - j = bestRun; - i = 1; - for ( i = i+j; i < *bitlen-2; i += 2){ - if ( bits[i] == 1 && bits[i + 1] == 0 ){ - bits[bitnum++] = 0; - } else if ( bits[i] == 0 && bits[i + 1] == 1 ){ - bits[bitnum++] = 1; + errCnt=bestErr; + if (errCnt<20){ + ii=bestRun; + i=1; + for (i=i+ii;i < *size-2;i+=2){ + if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ + BitStream[bitnum++]=0; + } else if((BitStream[i] == 0) && BitStream[i+1] == 1){ + BitStream[bitnum++]=1; } else { - bits[bitnum++] = 77; + BitStream[bitnum++]=77; + //errCnt++; } - if ( bitnum > 300 ) break; + if(bitnum>300) break; } - *bitlen = bitnum; - } + *size=bitnum; + } return errCnt; } - //by marshmellow //take 01 or 10 = 0 and 11 or 00 = 1 -int BiphaseRawDecode(uint8_t * bits, int *bitlen, int offset) +int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) { - uint8_t bitnum = 0; - uint32_t errCnt = 0; - uint32_t i = offset; - - for (; i < *bitlen-2; i += 2 ){ - if ( (bits[i]==1 && bits[i+1]==0)|| - (bits[i]==0 && bits[i+1]==1)){ - bits[bitnum++] = 1; - } else if ( (bits[i]==0 && bits[i+1]==0)|| - (bits[i]==1 && bits[i+1]==1)){ - bits[bitnum++] = 0; + uint8_t bitnum=0; + uint32_t errCnt =0; + uint32_t i; + i=offset; + for (;i<*size-2; i+=2){ + 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 { - bits[bitnum++] = 77; + BitStream[bitnum++]=77; errCnt++; } - if ( bitnum > 250) break; - } - *bitlen = bitnum; + if(bitnum>250) break; + } + *size=bitnum; return errCnt; } @@ -288,193 +327,188 @@ int BiphaseRawDecode(uint8_t * bits, int *bitlen, int offset) //takes 2 arguments - clock and invert both as integers //attempts to demodulate ask only //prints binary found and saves in graphbuffer for further commands -int askrawdemod(uint8_t *BinStream, int *bitLen, int *clk, int *invert) +int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) { - uint32_t i; - uint32_t initLoopMax = 200; - int high = 0, low = 128; - uint8_t BitStream[502] = {0x00}; - - *clk = DetectASKClock(BinStream, *bitLen, *clk); //clock default - - if (*clk < 8) *clk = 64; - if (*clk < 32) *clk = 32; - if (*invert != 1) *invert = 0; + uint32_t i; + // int invert=0; //invert default + int clk2 = *clk; + *clk=DetectASKClock(BinStream, *size, *clk); //clock default + //uint8_t BitStream[502] = {0}; - if (initLoopMax > *bitLen) - initLoopMax = *bitLen; - - // Detect high and lows - for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values - { - if (BinStream[i] > high) - high = BinStream[i]; - else if (BinStream[i] < low) - low = BinStream[i]; - } - - //throw away static - if ((high < 158)){ - return -2; - } - + //HACK: if clock not detected correctly - default + if (clk2==0 && *clk<8) *clk =64; + if (clk2==0 && *clk<32 && clk2==0) *clk=32; + if (*invert != 0 && *invert != 1) *invert =0; + uint32_t initLoopMax = 200; + if (initLoopMax > *size) initLoopMax=*size; + // Detect high and lows //25% fuzz in case highs and lows aren't clipped [marshmellow] - high = (int)(high * .75); - low = (int)(low+128 * .25); + int high, low, ans; + ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); + if (ans<1) return -2; //just noise - int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter - - uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - if (*clk==32) tol = 1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - - uint32_t gLen = *bitLen; - if (gLen > 500) gLen = 500; - - uint32_t j = 0; - uint8_t errCnt = 0; - uint32_t bestStart = *bitLen; - uint32_t bestErrCnt = (*bitLen / 1000); - uint32_t errCntLimit = bestErrCnt; - uint8_t midBit = 0; - - //loop to find first wave that works - for (j = 0; j < gLen; ++j){ - - if ((BinStream[j] >= high)||(BinStream[j] <= low)){ - lastBit = j - *clk; - //loop through to see if this start location works - for (i = j; i < *bitLen; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit += *clk; - BitStream[bitnum] = *invert; - bitnum++; - midBit = 0; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit += *clk; - BitStream[bitnum] = 1-*invert; - bitnum++; - midBit=0; - } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit = 1; - BitStream[bitnum] = 1 - *invert; - bitnum++; - } else if ((BinStream[i]>=high)&&(midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit = 1; - BitStream[bitnum] = *invert; - bitnum++; - } else if ((i-lastBit)>((*clk/2)+tol)&&(midBit==0)){ - //no mid bar found - midBit = 1; - BitStream[bitnum] = BitStream[bitnum-1]; - bitnum++; - } else { - //mid value found or no bar supposed to be here + //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); + int lastBit = 0; //set first clock check + uint32_t bitnum = 0; //output counter + uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock + // if they fall + or - this value + clock from last valid wave + if (*clk == 32) tol=1; //clock tolerance may not be needed anymore currently set to + // + or - 1 but could be increased for poor waves or removed entirely + uint32_t iii = 0; + uint32_t gLen = *size; + if (gLen > 500) gLen=500; + uint8_t errCnt =0; + uint32_t bestStart = *size; + uint32_t bestErrCnt = (*size/1000); + uint32_t maxErr = bestErrCnt; + uint8_t midBit=0; + //PrintAndLog("DEBUG - lastbit - %d",lastBit); + //loop to find first wave that works + for (iii=0; iii < gLen; ++iii){ + if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){ + lastBit=iii-*clk; + //loop through to see if this start location works + for (i = iii; i < *size; ++i) { + if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ + lastBit+=*clk; + midBit=0; + } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + midBit=0; + } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ + //no mid bar found + midBit=1; + } else { + //mid value found or no bar supposed to be here - if (( i - lastBit) > ( *clk + tol)){ - //should have hit a high or low based on clock!! + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (bitnum > 0){ - BitStream[bitnum] = 77; - bitnum++; - } + errCnt++; + lastBit+=*clk;//skip over until hit too many errors + if (errCnt > ((*size/1000))){ //allow 1 error for every 1000 samples else start over + errCnt=0; + break; + } + } + } + if ((i-iii)>(500 * *clk)) break; //got enough bits + } + //we got more than 64 good bits and not all errors + if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<(*size/1000))) { + //possible good read + if (errCnt==0){ + bestStart=iii; + bestErrCnt=errCnt; + break; //great read - finish + } + if (errCnt= high) && ((i-lastBit) > (*clk-tol))){ + lastBit += *clk; + BinStream[bitnum] = *invert; + bitnum++; + midBit=0; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + BinStream[bitnum] = 1-*invert; + bitnum++; + midBit=0; + } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + BinStream[bitnum] = 1 - *invert; + bitnum++; + } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + BinStream[bitnum] = *invert; + bitnum++; + } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ + //no mid bar found + midBit=1; + if (bitnum!=0) BinStream[bitnum] = BinStream[bitnum-1]; + bitnum++; + + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! - errCnt++; - lastBit += *clk;//skip over until hit too many errors - if (errCnt > errCntLimit){ //allow 1 error for every 1000 samples else start over - errCnt = 0; - bitnum = 0;//start over - break; - } - } - } - if (bitnum > 500) break; - } - //we got more than 64 good bits and not all errors - //possible good read - if ((bitnum > (64 + errCnt)) && (errCnt < errCntLimit)) { - - //great read - finish - if (errCnt == 0) break; - - //if current run == bestErrCnt run (after exhausted testing) then finish - if (bestStart == j) break; - - //set this as new best run - if (errCnt < bestErrCnt){ - bestErrCnt = errCnt; - bestStart = j; - } - } - } - if (j >= gLen){ //exhausted test - //if there was a ok test go back to that one and re-run the best run (then dump after that run) - if (bestErrCnt < errCntLimit) - j = bestStart; - } - } - if (bitnum > 16){ + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + if (bitnum > 0){ + BinStream[bitnum]=77; + bitnum++; + } - for (i = 0; i < bitnum; ++i){ - BinStream[i] = BitStream[i]; + lastBit+=*clk;//skip over error + } + } + if (bitnum >=400) break; } - *bitLen = bitnum; - } else { + *size=bitnum; + } else{ + *invert=bestStart; + *clk=iii; return -1; } - return errCnt; + return bestErrCnt; } -//translate wave to 11111100000 (1 for each short wave 0 for each long wave) +//translate wave to 11111100000 (1 for each short wave 0 for each long wave) size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) { uint32_t last_transition = 0; uint32_t idx = 1; - uint32_t maxVal = 0; - - if (fchigh == 0) fchigh = 10; - if (fclow == 0) fclow = 8; - - // we do care about the actual theshold value as sometimes near the center of the - // wave we may get static that changes direction of wave for one value - // if our value is too low it might affect the read. and if our tag or - // antenna is weak a setting too high might not see anything. [marshmellow] - if ( size < 100) - return 0; - - // Find high from first 100 samples - for ( idx = 1; idx < 100; idx++ ){ - if ( maxVal < dest[idx]) - maxVal = dest[idx]; - } - - // set close to the top of the wave threshold with 25% margin for error - // less likely to get a false transition up there. - // (but have to be careful not to go too high and miss some short waves) - uint8_t threshold_value = (uint8_t)(maxVal * .75); - + //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; + // sync to first lo-hi transition, and threshold + // Need to threshold first sample - - dest[0] = (dest[0] < threshold_value) ? 0 : 1; + + if(dest[0] < threshold_value) dest[0] = 0; + else dest[0] = 1; 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 // 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++) { - // threshold current value - dest[idx] = (dest[idx] < threshold_value) ? 0 : 1; + + 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 ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise //do nothing with extra garbage - } else if ((idx - last_transition) < ( fchigh - 1 )) { //6-8 = 8 waves + } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves dest[numBits]=1; } else { //9+ = 10 waves dest[numBits]=0; @@ -483,124 +517,131 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow numBits++; } } - //it returns the number of bytes, but each byte represents a bit: 1 or 0 - return numBits; + return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0 } uint32_t myround2(float f) { - if (f >= 2000) return 2000;//something bad happened - return (uint32_t) (f + (float)0.5); + if (f >= 2000) return 2000;//something bad happened + return (uint32_t) (f + (float)0.5); } -//translate 11111100000 to 10 -size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, uint8_t invert, uint8_t fchigh, uint8_t fclow ) +//translate 11111100000 to 10 +size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, + uint8_t invert, uint8_t fchigh, uint8_t fclow) { - uint8_t lastval = dest[0]; - uint32_t idx = 0; - uint32_t n = 1; - size_t numBits = 0; + uint8_t lastval=dest[0]; + uint32_t idx=0; + size_t numBits=0; + uint32_t n=1; - for( idx = 1; idx < size; idx++) { + for( idx=1; idx < size; idx++) { - if (dest[idx] == lastval) { + if (dest[idx]==lastval) { n++; continue; } //if lastval was 1, we have a 1->0 crossing - if ( dest[idx-1] == 1 ) { - n = myround2( (float)( n + 1 ) / ((float)(rfLen)/(float)fclow)); - } else { // 0->1 crossing - n = myround2( (float)( n + 1 ) / ((float)(rfLen-2)/(float)fchigh)); //-2 for fudge factor + 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 (n == 0) n = 1; - if(n < maxConsequtiveBits) //Consecutive + if(n < maxConsequtiveBits) //Consecutive { - if(invert == 0){ //invert bits + if(invert==0){ //invert bits memset(dest+numBits, dest[idx-1] , n); }else{ - memset(dest+numBits, dest[idx-1]^1 , n); - } + memset(dest+numBits, dest[idx-1]^1 , n); + } numBits += n; } - n = 0; - lastval = dest[idx]; + n=0; + lastval=dest[idx]; }//end for 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) { // FSK demodulator size = fsk_wave_demod(dest, size, fchigh, fclow); - if ( size > 0 ) - size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow); + size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow); return size; } // loop to get raw HID waveform then FSK demodulate the TAG ID from it -int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) +int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) { - size_t idx = 0; - int numshifts = 0; + if (justNoise(dest, *size)) return -1; - // FSK demodulator - size = fskdemod(dest, size, 50, 0, 10, 8); + size_t numStart=0, size2=*size, startIdx=0; + // FSK demodulator + *size = fskdemod(dest, size2,50,1,10,8); //fsk2a + if (*size < 96) return -2; + // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 + uint8_t preamble[] = {0,0,0,1,1,1,0,1}; + // find bitstring in array + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found - // final loop, go over previously decoded manchester data and decode into usable tag ID - // 111000 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0 - uint8_t frame_marker_mask[] = {1,1,1,0,0,0}; + numStart = startIdx + sizeof(preamble); + // final loop, go over previously decoded FSK data and manchester decode into usable tag ID + for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ + if (dest[idx] == dest[idx+1]){ + return -4; //not manchester data + } + *hi2 = (*hi2<<1)|(*hi>>31); + *hi = (*hi<<1)|(*lo>>31); + //Then, shift in a 0 or one into low + if (dest[idx] && !dest[idx+1]) // 1 0 + *lo=(*lo<<1)|1; + else // 0 1 + *lo=(*lo<<1)|0; + } + return (int)startIdx; +} - uint8_t mask_len = sizeof frame_marker_mask / sizeof frame_marker_mask[0]; +// loop to get raw paradox waveform then FSK demodulate the TAG ID from it +int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) +{ + if (justNoise(dest, *size)) return -1; - //one scan - while( idx + mask_len < size) { - // search for a start of frame marker - if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) - { // frame marker found - idx += mask_len; - while(dest[idx] != dest[idx+1] && idx < size-2) - { - // Keep going until next frame marker (or error) - // Shift in a bit. Start by shifting high registers - *hi2 = ( *hi2 << 1 ) | ( *hi >> 31 ); - *hi = ( *hi << 1 ) | ( *lo >> 31 ); - //Then, shift in a 0 or one into low - if (dest[idx] && !dest[idx+1]) // 1 0 - *lo = ( *lo << 1 ) | 0; - else // 0 1 - *lo = ( *lo << 1 ) | 1; - numshifts++; - idx += 2; - } - // Hopefully, we read a tag and hit upon the next frame marker - if(idx + mask_len < size) - { - if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) - { - //good return - return idx; - } - } - // reset - *hi2 = *hi = *lo = 0; - numshifts = 0; - }else { - idx++; - } + size_t numStart=0, size2=*size, startIdx=0; + // FSK demodulator + *size = fskdemod(dest, size2,50,1,10,8); //fsk2a + if (*size < 96) return -2; + + // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 + uint8_t preamble[] = {0,0,0,0,1,1,1,1}; + + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found + + numStart = startIdx + sizeof(preamble); + // final loop, go over previously decoded FSK data and manchester decode into usable tag ID + for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ + if (dest[idx] == dest[idx+1]) + return -4; //not manchester data + *hi2 = (*hi2<<1)|(*hi>>31); + *hi = (*hi<<1)|(*lo>>31); + //Then, shift in a 0 or one into low + if (dest[idx] && !dest[idx+1]) // 1 0 + *lo=(*lo<<1)|1; + else // 0 1 + *lo=(*lo<<1)|0; } - return -1; + return (int)startIdx; } -uint32_t bytebits_to_byte(uint8_t *src, int numbits) +uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) { - //HACK: potential overflow in numbits is larger then uint32 bits. - uint32_t num = 0; - for(int i = 0 ; i < numbits ; ++i) { + for(int i = 0 ; i < numbits ; i++) + { num = (num << 1) | (*src); src++; } @@ -609,27 +650,12 @@ uint32_t bytebits_to_byte(uint8_t *src, int numbits) int IOdemodFSK(uint8_t *dest, size_t size) { + if (justNoise(dest, size)) return -1; //make sure buffer has data - if (size < 100) return -1; - - uint32_t idx = 0; - uint8_t testMax = 0; - - //test samples are not just noise - for (; idx < 65; ++idx ){ - if (testMax < dest[idx]) - testMax = dest[idx]; - } - - //if not just noise - if (testMax < 170) return -2; - + if (size < 66*64) return -2; // FSK demodulator - size = fskdemod(dest, size, 64, 1, 10, 8); // RF/64 and invert - - //did we get a good demod? - if (size < 65) return -3; - + size = fskdemod(dest, size, 64, 1, 10, 8); // FSK2a RF/64 + if (size < 65) return -3; //did we get a good demod? //Index map //0 10 20 30 40 50 60 //| | | | | | | @@ -639,25 +665,83 @@ int IOdemodFSK(uint8_t *dest, size_t size) // //XSF(version)facility:codeone+codetwo //Handle the data - - uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1}; - - for( idx = 0; idx < (size - 65); ++idx) { - if ( memcmp(dest + idx, mask, sizeof(mask))==0) { - //frame marker found - if (!dest[idx+8] && - dest[idx+17] == 1 && - dest[idx+26] == 1 && - dest[idx+35] == 1 && - dest[idx+44] == 1 && - dest[idx+53] == 1){ - //confirmed proper separator bits found - //return start position - return (int) idx; - } - } + size_t startIdx = 0; + uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1}; + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx); + if (errChk == 0) return -4; //preamble not found + + if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){ + //confirmed proper separator bits found + //return start position + 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) +{ + 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; } - return 0; + // if we got here then all the parities passed + //return ID start index and size + return bitCnt; +} + +// by marshmellow +// FSK Demod then try to locate an AWID ID +int AWIDdemodFSK(uint8_t *dest, size_t *size) +{ + //make sure buffer has enough data + if (*size < 96*50) return -1; + + if (justNoise(dest, *size)) return -2; + + // FSK demodulator + *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 + if (*size < 96) return -3; //did we get a good demod? + + uint8_t preamble[] = {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 + if (*size != 96) return -5; + return (int)startIdx; +} + +// by marshmellow +// 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; + + //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? + + 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 + if (*size != 128) return -3; + return (int)startIdx; } // by marshmellow @@ -665,86 +749,582 @@ int IOdemodFSK(uint8_t *dest, size_t size) // maybe somehow adjust peak trimming value based on samples to fix? int DetectASKClock(uint8_t dest[], size_t size, int clock) { - int i = 0; - int clk[] = {16,32,40,50,64,100,128,256}; - uint8_t clkLen = sizeof clk / sizeof clk[0]; - + int i=0; + int clk[]={8,16,32,40,50,64,100,128,256}; + int loopCnt = 256; //don't need to loop through entire array... + if (size= peak) || (dest[ii] <= low)){ + errCnt=0; + // now that we have the first one lined up test rest of wave array + for (i=0; i<((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ + if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ + }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ + }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ + }else{ //error no peak detected + errCnt++; + } + } + //if we found no errors then we can stop here + // this is correct one - return this clock + //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i); + if(errCnt==0 && clkCnt<6) return clk[clkCnt]; + //if we found errors see if it is lowest so far and save it as best run + if(errCnt peak) - peak = dest[i]; - if(dest[i] < low) - low = dest[i]; - } + int peak, low; + getHiLo(dest, loopCnt, &peak, &low, 75, 75); - peak = (int)(peak * .75); - low = (int)(low+128 * .25); - - int ii, cnt, bestErr, tol = 0; - int errCnt[clkLen]; - memset(errCnt, 0x00, clkLen); - - int tmpIndex, tmphigh, tmplow; - + //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low); + int ii; + uint8_t clkCnt; + uint8_t tol = 0; + int peakcnt=0; + int errCnt=0; + int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000}; + int peaksdet[]={0,0,0,0,0,0,0,0}; //test each valid clock from smallest to greatest to see which lines up - for( cnt = 0; cnt < clkLen; ++cnt ){ - - tol = (clk[cnt] == 32) ? 1 : 0; - bestErr = 1000; - tmpIndex = tmphigh = tmplow = 0; - - //try lining up the peaks by moving starting point (try first 256) - for (ii=0; ii < loopCnt; ++ii){ - - // not a peak? continue - if ( (dest[ii] < peak) && (dest[ii] > low)) - continue; - - errCnt[cnt] = 0; - - // now that we have the first one lined up test rest of wave array - for ( i = 0; i < ((int)(size / clk[cnt]) - 1); ++i){ - - tmpIndex = ii + (i * clk[cnt] ); - tmplow = dest[ tmpIndex - tol]; - tmphigh = dest[ tmpIndex + tol]; - - if ( dest[tmpIndex] >= peak || dest[tmpIndex] <= low ) { + for(clkCnt=0; clkCnt < 7; ++clkCnt){ + if (clk[clkCnt] <= 32){ + tol=1; + }else{ + tol=0; + } + //try lining up the peaks by moving starting point (try first 256) + for (ii=0; ii< loopCnt; ++ii){ + if ((dest[ii] >= 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++; + } } - else if ( tmplow >= peak || tmplow <= low){ - } - else if ( tmphigh >= peak || tmphigh <= low){ + if(peakcnt>peaksdet[clkCnt]) { + peaksdet[clkCnt]=peakcnt; + bestErr[clkCnt]=errCnt; } - else - errCnt[cnt]++; //error no peak detected } + } + } + 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]; +} - //if we found no errors this is correct one - return this clock - if ( errCnt[cnt] == 0 ) - return clk[cnt]; +// by marshmellow (attempt to get rid of high immediately after a low) +void pskCleanWave(uint8_t *BitStream, size_t size) +{ + int i; + int gap = 4; + int newLow=0; + int newHigh=0; + int high, low; + getHiLo(BitStream, size, &high, &low, 80, 90); + + for (i=0; i < size; ++i){ + if (newLow == 1){ + if (BitStream[i]>low){ + BitStream[i]=low+8; + gap--; + } + if (gap == 0){ + newLow=0; + gap=4; + } + }else if (newHigh == 1){ + if (BitStream[i]= high) newHigh=1; + } + return; +} - if ( errCnt[cnt] < bestErr) - bestErr = errCnt[cnt]; +// by marshmellow +// convert psk1 demod to psk2 demod +// only transition waves are 1s +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 (bitnum>16){ + *size=bitnum; + } else return -1; + return errCnt; +} + +//by marshmellow +//detects the bit clock for FSK given the high and low Field Clocks +uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) +{ + uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; + uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfLensFnd = 0; + uint8_t lastFCcnt=0; + uint32_t fcCounter = 0; + uint16_t rfCounter = 0; + uint8_t firstBitFnd = 0; + size_t i; + + uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); + rfLensFnd=0; + fcCounter=0; + rfCounter=0; + firstBitFnd=0; + //PrintAndLog("DEBUG: fcTol: %d",fcTol); + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) + break; + + for (; i < size-1; i++){ + if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){ + // new peak + fcCounter++; + rfCounter++; + // if we got less than the small fc + tolerance then set it to the small fc + if (fcCounter < fcLow+fcTol) + fcCounter = fcLow; + else //set it to the large fc + fcCounter = fcHigh; + + //look for bit clock (rf/xx) + if ((fcCounterlastFCcnt)){ + //not the same size as the last wave - start of new bit sequence + + if (firstBitFnd>1){ //skip first wave change - probably not a complete bit + for (int ii=0; ii<15; ii++){ + if (rfLens[ii]==rfCounter){ + rfCnts[ii]++; + rfCounter=0; + break; + } + } + if (rfCounter>0 && rfLensFnd<15){ + //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); + rfCnts[rfLensFnd]++; + rfLens[rfLensFnd++]=rfCounter; + } + } else { + firstBitFnd++; + } + rfCounter=0; + lastFCcnt=fcCounter; + } + fcCounter=0; + } else { + // count sample + fcCounter++; + rfCounter++; + } + } + uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; + + for (i=0; i<15; i++){ + //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); + //get highest 2 RF values (might need to get more values to compare or compare all?) + if (rfCnts[i]>rfCnts[rfHighest]){ + rfHighest3=rfHighest2; + rfHighest2=rfHighest; + rfHighest=i; + } else if(rfCnts[i]>rfCnts[rfHighest2]){ + rfHighest3=rfHighest2; + rfHighest2=i; + } else if(rfCnts[i]>rfCnts[rfHighest3]){ + rfHighest3=i; + } + } + // set allowed clock remainder tolerance to be 1 large field clock length+1 + // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off + uint8_t tol1 = fcHigh+1; + + //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); + + // loop to find the highest clock that has a remainder less than the tolerance + // compare samples counted divided by + int ii=7; + for (; ii>=0; ii--){ + if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ + break; + } + } + } + } + + if (ii<0) return 0; // oops we went too far + + return clk[ii]; +} + +//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) +{ + uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; + uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; + uint8_t fcLensFnd = 0; + uint8_t lastFCcnt=0; + uint32_t fcCounter = 0; + size_t i; + + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) + break; + + for (; i < size-1; i++){ + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ + // new up transition + fcCounter++; + + //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) + if (lastFCcnt==5 && fcCounter==9) fcCounter--; + //if odd and not rc/5 add one (for when we get a fc 9 instead of 10) + if ((fcCounter==9 && fcCounter & 1) || fcCounter==4) fcCounter++; + + // save last field clock count (fc/xx) + // find which fcLens to save it to: + for (int ii=0; ii<10; ii++){ + if (fcLens[ii]==fcCounter){ + fcCnts[ii]++; + fcCounter=0; + break; + } + } + if (fcCounter>0 && fcLensFnd<10){ + //add new fc length + fcCnts[fcLensFnd]++; + fcLens[fcLensFnd++]=fcCounter; + } + fcCounter=0; + } else { + // count sample + fcCounter++; + } + } + + uint8_t best1=9, best2=9, best3=9; + uint16_t maxCnt1=0; + // go through fclens and find which ones are bigest 2 + for (i=0; i<10; i++){ + // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); + // get the 3 best FC values + if (fcCnts[i]>maxCnt1) { + best3=best2; + best2=best1; + maxCnt1=fcCnts[i]; + best1=i; + } else if(fcCnts[i]>fcCnts[best2]){ + best3=best2; + best2=i; + } else if(fcCnts[i]>fcCnts[best3]){ + best3=i; + } + } + uint8_t fcH=0, fcL=0; + if (fcLens[best1]>fcLens[best2]){ + fcH=fcLens[best1]; + fcL=fcLens[best2]; + } else{ + fcH=fcLens[best2]; + fcL=fcLens[best1]; + } + + // TODO: take top 3 answers and compare to known Field clocks to get top 2 + + uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; + // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); + + return fcs; }