// 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};
{
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++;
if (smplCnt > clk-(clk/4)-1) { //full clock
if (smplCnt > clk + (clk/4)+1) { //too many samples
errCnt++;
- BinStream[bitCnt++]=77;
+ BinStream[bitCnt++]=7;
} else if (waveHigh) {
BinStream[bitCnt++] = invert;
BinStream[bitCnt++] = invert;
//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
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;
}
+ //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++]=77;
+ BitStream[bitnum++]=7;
}
if(bitnum>MaxBits) break;
}
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;
lastBit = start - *clk;
for (i = start; i < *size; ++i) {
- if (i - lastBit > *clk){
+ if (i - lastBit == *clk){
if (BinStream[i] >= high) {
BinStream[bitnum++] = *invert;
} else if (BinStream[i] <= low) {
BinStream[bitnum++] = *invert ^ 1;
} else {
if (bitnum > 0) {
- BinStream[bitnum++]=77;
+ BinStream[bitnum++]=7;
errCnt++;
}
}
midBit = 0;
lastBit += *clk;
- } else if (i-lastBit > (*clk/2) && midBit == 0){
+ } else if (i-lastBit == (*clk/2) && midBit == 0){
if (BinStream[i] >= high) {
BinStream[bitnum++] = *invert;
} else if (BinStream[i] <= low) {
BinStream[bitnum++] = *invert ^ 1;
} else {
-
BinStream[bitnum] = BinStream[bitnum-1];
bitnum++;
}
}
-uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
+uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
{
uint16_t allPeaks=1;
uint16_t cntPeaks=0;
- size_t loopEnd = 572;
+ size_t loopEnd = 512+60;
if (loopEnd > size) loopEnd = size;
for (size_t i=60; i<loopEnd; i++){
if (dest[i]>low && dest[i]<high)
// 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 = 0;
+ 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
+ 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
int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
{
size_t i=1;
- uint8_t clk[]={255,8,16,32,40,50,64,100,128,255};
+ 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==0) return -1;
- if (size <= loopCnt) loopCnt = size-1; //not enough samples
+ if (size <= loopCnt) return -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;
+ for (;i<clkEnd;++i)
+ if (clk[i] == *clock) clockFnd = i;
//clock found but continue to find best startpos
//get high and low peak
if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1;
//test for large clean peaks
- if (DetectCleanAskWave(dest, size, peak, low)==1){
- int ans = DetectStrongAskClock(dest, size);
- for (i=8; i>1; i--){
- if (clk[i] == ans) {
- *clock = ans;
- clockFnd = i;
- break; //clock found but continue to find best startpos
+ if (!clockFnd){
+ if (DetectCleanAskWave(dest, size, peak, low)==1){
+ int ans = DetectStrongAskClock(dest, size, peak, low);
+ 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]
+ }
}
}
}
+
uint8_t ii;
uint8_t clkCnt, tol = 0;
uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
uint8_t bestStart[]={0,0,0,0,0,0,0,0,0};
size_t errCnt = 0;
size_t arrLoc, loopEnd;
- //test each valid clock from smallest to greatest to see which lines up
- uint8_t clkEnd=9;
- if (clockFnd>0) clkEnd=clockFnd+1;
- else clockFnd=1;
- for(clkCnt=clockFnd; clkCnt < clkEnd; clkCnt++){
+ 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 < clkEnd; clkCnt++){
if (clk[clkCnt] == 32){
tol=1;
}else{
tol=0;
}
- if (!maxErr && loopCnt>clk[clkCnt]*3) loopCnt=clk[clkCnt]*3;
+ //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 few clocks)
- for (ii=0; ii < loopCnt-tol-clk[clkCnt]; ii++){
+ for (ii=0; ii < loopCnt; ii++){
if (dest[ii] < peak && dest[ii] > low) continue;
errCnt=0;
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(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
}
}
}
- uint8_t iii=0;
+ uint8_t iii;
uint8_t best=0;
- for (iii=0; iii<8; ++iii){
+ for (iii=1; iii<clkEnd; ++iii){
if (bestErr[iii] < bestErr[best]){
if (bestErr[iii] == 0) bestErr[iii]=1;
// current best bit to error ratio vs new bit to error ratio
}
}
}
- if (bestErr[best] > maxErr) return -1;
- *clock = clk[best];
+ //if (bestErr[best] > maxErr) return -1;
+ if (!clockFnd) *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