X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/23f0a7d862fb41d21dd90403cb657e91705bf886..6e98444637baaa183812fad93cd7c03d645ba95e:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index df30aba4..c00222b3 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -172,7 +172,7 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr) { size_t i; - int start = DetectASKClock(BinStream, *size, clk, 20); //clock default + int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default if (*clk==0 || start < 0) return -3; if (*invert != 1) *invert=0; uint8_t initLoopMax = 255; @@ -188,59 +188,14 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max return manrawdecode(BinStream, size); } - // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check + int lastBit; //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*3) initLoopMax = *clk * 3; 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-tol-*clk; ++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) > (32)) && (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; - } - } - 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) { + lastBit = start - *clk; + for (i = start; i < *size; ++i) { if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ //high found and we are expecting a bar lastBit += *clk; @@ -261,7 +216,7 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max if (bitnum >= MaxBits) break; } *size = bitnum; - return bestErrCnt; + return errCnt; } //by marshmellow @@ -381,13 +336,13 @@ void askAmp(uint8_t *BitStream, size_t size) int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp) { if (*size==0) return -1; - int start = DetectASKClock(BinStream, *size, clk, 20); //clock default + int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default if (*clk==0 || start < 0) return -1; if (*invert != 1) *invert = 0; if (amp==1) askAmp(BinStream, *size); 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; @@ -398,67 +353,13 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max if (DetectCleanAskWave(BinStream, *size, high, low)) return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); - 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, errCnt = 0, bitnum = 0; //output counter uint8_t midBit = 0; - size_t bestStart = start, bestErrCnt = 0; //(*size/1000); size_t MaxBits = 1024; + lastBit = start - *clk; - //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance - if (!maxErr && initLoopMax > *clk*3) initLoopMax = *clk * 3; - //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 - *clk; ++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 32 good bits and not all errors - if ((((i-iii)/ *clk) > 32) && (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; - - for (i = bestStart; i < *size; ++i) { + for (i = start; i < *size; ++i) { if (i - lastBit > *clk){ if (BinStream[i] >= high) { BinStream[bitnum++] = *invert; @@ -861,15 +762,17 @@ 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 loopCnt = 255; //don't need to loop through entire array... if (size==0) return -1; if (size <= loopCnt) loopCnt = size-1; //not enough samples - //if we already have a valid clock quit - - for (;i<8;++i) - if (clk[i] == *clock) return 0; + + //if we already have a valid clock + uint8_t clockFnd=0; + for (;i<9;++i) + if (clk[i] == *clock) clockFnd=i; + //clock found but continue to find best startpos //get high and low peak int peak, low; @@ -878,10 +781,11 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) //test for large clean peaks if (DetectCleanAskWave(dest, size, peak, low)==1){ int ans = DetectStrongAskClock(dest, size); - for (i=7; i>0; i--){ + for (i=8; i>1; i--){ if (clk[i] == ans) { *clock = ans; - return 0; + clockFnd = i; + break; //clock found but continue to find best startpos } } } @@ -892,15 +796,19 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) size_t errCnt = 0; size_t arrLoc, loopEnd; //test each valid clock from smallest to greatest to see which lines up - for(clkCnt=0; clkCnt < 8; clkCnt++){ + uint8_t clkEnd=9; + if (clockFnd>0) clkEnd=clockFnd+1; + else clockFnd=1; + + for(clkCnt=clockFnd; clkCnt < clkEnd; clkCnt++){ if (clk[clkCnt] == 32){ tol=1; }else{ tol=0; } - if (!maxErr && loopCnt>clk[clkCnt]*2) loopCnt=clk[clkCnt]*2; + if (!maxErr && loopCnt>clk[clkCnt]*3) loopCnt=clk[clkCnt]*3; 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-tol-clk[clkCnt]; ii++){ if (dest[ii] < peak && dest[ii] > low) continue;