// 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;
- }
+ if (BitStream[1]>1) return 0; //allow only 1s and 0s
+
// 111111111 bit pattern represent start of frame
// include 0 in front to help get start pos
uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
return 0;
}
+// 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++;
+ } else if (BinStream[i] <= low && !waveHigh){
+ smplCnt++;
+ } else { //transition
+ if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
+ if (smplCnt > clk-(clk/4)-1) { //full clock
+ if (smplCnt > clk + (clk/4)+1) { //too many samples
+ errCnt++;
+ BinStream[bitCnt++]=7;
+ } else if (waveHigh) {
+ BinStream[bitCnt++] = invert;
+ BinStream[bitCnt++] = invert;
+ } else if (!waveHigh) {
+ BinStream[bitCnt++] = invert ^ 1;
+ BinStream[bitCnt++] = invert ^ 1;
+ }
+ waveHigh ^= 1;
+ smplCnt = 0;
+ } else if (smplCnt > (clk/2) - (clk/4)-1) {
+ if (waveHigh) {
+ BinStream[bitCnt++] = invert;
+ } else if (!waveHigh) {
+ BinStream[bitCnt++] = invert ^ 1;
+ }
+ waveHigh ^= 1;
+ smplCnt = 0;
+ } else if (!bitCnt) {
+ //first bit
+ waveHigh = (BinStream[i] >= high);
+ smplCnt = 1;
+ } else {
+ smplCnt++;
+ //transition bit oops
+ }
+ } else { //haven't hit new high or new low yet
+ smplCnt++;
+ }
+ }
+ }
+ *size = bitCnt;
+ return errCnt;
+}
+
//by marshmellow
//takes 3 arguments - clock, invert, maxErr as integers
//attempts to demodulate ask while decoding manchester
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;
int high, low;
if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) return -2; //just noise
+ // if clean clipped waves detected run alternate demod
+ if (DetectCleanAskWave(BinStream, *size, high, low)) {
+ cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
+ 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 * 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;
- }
- }
- 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;
//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;
+ BinStream[bitnum++] = 7;
errCnt++;
}
lastBit += *clk;//skip over error
if (bitnum >= MaxBits) break;
}
*size = bitnum;
- return bestErrCnt;
+ return errCnt;
}
//by marshmellow
size_t i, ii;
uint16_t bestErr = 1000, bestRun = 0;
if (size == 0) return -1;
+ //find correct start position [alignment]
for (ii=0;ii<2;++ii){
for (i=ii; i<*size-2; i+=2)
if (BitStream[i]==BitStream[i+1])
}
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;
- }
- if(bitnum>MaxBits) break;
+ //decode
+ 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++]=7;
}
- *size=bitnum;
+ if(bitnum>MaxBits) break;
}
+ *size=bitnum;
return bestErr;
}
for (i=offset; i<*size-3; i+=2){
//check for phase error
if (BitStream[i+1]==BitStream[i+2]) {
- BitStream[bitnum++]=77;
+ BitStream[bitnum++]=7;
errCnt++;
}
if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){
} else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
BitStream[bitnum++]=invert;
} else {
- BitStream[bitnum++]=77;
+ BitStream[bitnum++]=7;
errCnt++;
}
if(bitnum>MaxBits) break;
return;
}
-// 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++;
- } else if (BinStream[i] <= low && !waveHigh){
- smplCnt++;
- } else { //transition
- if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
- if (smplCnt > clk-(clk/4)-1) { //full clock
- if (smplCnt > clk + (clk/4)+1) { //too many samples
- errCnt++;
- BinStream[bitCnt++]=77;
- } else if (waveHigh) {
- BinStream[bitCnt++] = invert;
- BinStream[bitCnt++] = invert;
- } else if (!waveHigh) {
- BinStream[bitCnt++] = invert ^ 1;
- BinStream[bitCnt++] = invert ^ 1;
- }
- waveHigh ^= 1;
- smplCnt = 0;
- } else if (smplCnt > (clk/2) - (clk/4)-1) {
- if (waveHigh) {
- BinStream[bitCnt++] = invert;
- } else if (!waveHigh) {
- BinStream[bitCnt++] = invert ^ 1;
- }
- waveHigh ^= 1;
- smplCnt = 0;
- } else if (!bitCnt) {
- //first bit
- waveHigh = (BinStream[i] >= high);
- smplCnt = 1;
- } else {
- smplCnt++;
- //transition bit oops
- }
- } else { //haven't hit new high or new low yet
- smplCnt++;
- }
- }
- }
- *size = bitCnt;
- return errCnt;
-}
-
//by marshmellow
//takes 3 arguments - clock, invert and maxErr as integers
//attempts to demodulate ask only
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;
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 * 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<bestErrCnt){ //set this as new best run
- bestErrCnt=errCnt;
- bestStart = iii;
- }
- }
- errCnt=0;
- }
- }
- }
- if (bestErrCnt > 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;
BinStream[bitnum++] = *invert ^ 1;
} else {
if (bitnum > 0) {
- BinStream[bitnum++]=77;
+ BinStream[bitnum++]=7;
errCnt++;
}
}
// 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 <= 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==0) return -1;
+ if (size <= loopCnt) loopCnt = size-1; //not enough samples
+
+ //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;
//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;
+ 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]
}
}
}
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;
+ //if no errors allowed - keep start within the first clock
+ if (!maxErr && size > clk[clkCnt]*3 + tol) loopCnt=clk[clkCnt]*2;
bestErr[clkCnt]=1000;
- //try lining up the peaks by moving starting point (try first 256)
- for (ii=0; ii < loopCnt; ii++){
+ //try lining up the peaks by moving starting point (try first few clocks)
+ for (ii=0; ii < loopCnt-clk[clkCnt]; ii++){
if (dest[ii] < peak && dest[ii] > low) continue;
errCnt=0;
}
}
}
- if (bestErr[best] > maxErr) return -1;
+ //if (bestErr[best] > maxErr) return -1;
*clock = clk[best];
return bestStart[best];
}
size_t i=1;
uint8_t lastBit=BitStream[0];
for (; i<size; i++){
- if (BitStream[i]==77){
+ if (BitStream[i]==7){
//ignore errors
} else if (lastBit!=BitStream[i]){
lastBit=BitStream[i];
if (ignoreCnt == 0){
bitHigh = 0;
if (errBitHigh == 1){
- dest[bitnum++] = 77;
+ dest[bitnum++] = 7;
errCnt++;
}
errBitHigh=0;
//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
projects / proxmark3-svn / blobdiff