- 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<loopCnt) loopCnt = size;
-
- //if we already have a valid clock quit
- size_t i=1;
- for (; i < 8; ++i)
- if (clk[i] == clock) return clock;
-
- size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0;
- uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1;
- uint16_t peakcnt=0, errCnt=0, waveLenCnt=0;
- uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
- uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0};
- countFC(dest, size, &fc);
- //PrintAndLog("DEBUG: FC: %d",fc);
-
- //find first full wave
- for (i=0; i<loopCnt; i++){
- if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
- if (waveStart == 0) {
- waveStart = i+1;
- //PrintAndLog("DEBUG: waveStart: %d",waveStart);
- } else {
- waveEnd = i+1;
- //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
- waveLenCnt = waveEnd-waveStart;
- if (waveLenCnt > fc){
- firstFullWave = waveStart;
- fullWaveLen=waveLenCnt;
- break;
- }
- waveStart=0;
- }
- }
- }
- //PrintAndLog("DEBUG: 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--){
- lastClkBit = firstFullWave; //set end of wave as clock align
- waveStart = 0;
- errCnt=0;
- peakcnt=0;
- //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit);
-
- for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){
- //top edge of wave = start of new wave
- if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
- if (waveStart == 0) {
- waveStart = i+1;
- waveLenCnt=0;
- } else { //waveEnd
- waveEnd = i+1;
- 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 (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit
- peakcnt++;
- lastClkBit+=clk[clkCnt];
- } else if (i<lastClkBit+8){
- //noise after a phase shift - ignore
- } else { //phase shift before supposed to based on clock
- errCnt++;
- }
- } else if (i+1 > lastClkBit + clk[clkCnt] + tol + fc){
- lastClkBit+=clk[clkCnt]; //no phase shift but clock bit
- }
- waveStart=i+1;
- }
- }
- }
- if (errCnt == 0){
- return clk[clkCnt];
- }
- if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
- if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt;
- }
- //all tested with errors
- //return the highest clk with the most peaks found
- uint8_t best=7;
- for (i=7; i>=1; i--){
- 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]);
- }
- return clk[best];
+ 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<loopCnt) loopCnt = size;
+
+ //if we already have a valid clock quit
+ size_t i=1;
+ for (; i < 8; ++i)
+ if (clk[i] == clock) return clock;
+
+ size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0;
+ uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1;
+ uint16_t peakcnt=0, errCnt=0, waveLenCnt=0;
+ uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
+ uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0};
+ fc = countFC(dest, size, 0);
+ if (fc!=2 && fc!=4 && fc!=8) return -1;
+ //PrintAndLog("DEBUG: FC: %d",fc);
+
+ //find first full wave
+ for (i=0; i<loopCnt; i++){
+ if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
+ if (waveStart == 0) {
+ waveStart = i+1;
+ //PrintAndLog("DEBUG: waveStart: %d",waveStart);
+ } else {
+ waveEnd = i+1;
+ //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+ waveLenCnt = waveEnd-waveStart;
+ if (waveLenCnt > fc){
+ firstFullWave = waveStart;
+ fullWaveLen=waveLenCnt;
+ break;
+ }
+ waveStart=0;
+ }
+ }
+ }
+ //PrintAndLog("DEBUG: 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--){
+ lastClkBit = firstFullWave; //set end of wave as clock align
+ waveStart = 0;
+ errCnt=0;
+ peakcnt=0;
+ //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit);
+
+ for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){
+ //top edge of wave = start of new wave
+ if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
+ if (waveStart == 0) {
+ waveStart = i+1;
+ waveLenCnt=0;
+ } else { //waveEnd
+ waveEnd = i+1;
+ 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 (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit
+ peakcnt++;
+ lastClkBit+=clk[clkCnt];
+ } else if (i<lastClkBit+8){
+ //noise after a phase shift - ignore
+ } else { //phase shift before supposed to based on clock
+ errCnt++;
+ }
+ } else if (i+1 > lastClkBit + clk[clkCnt] + tol + fc){
+ lastClkBit+=clk[clkCnt]; //no phase shift but clock bit
+ }
+ waveStart=i+1;
+ }
+ }
+ }
+ if (errCnt == 0){
+ return clk[clkCnt];
+ }
+ if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
+ if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt;
+ }
+ //all tested with errors
+ //return the highest clk with the most peaks found
+ uint8_t best=7;
+ for (i=7; i>=1; i--){
+ 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]);
+ }
+ return clk[best];