X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/7009555e448259178dbd7443c30cd96047647b2e..a903be43617ef2b1d1650e18943368eca9019aab:/common/lfdemod.c?ds=inline

diff --git a/common/lfdemod.c b/common/lfdemod.c
index fae61206..7d40d22e 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -11,8 +11,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include "lfdemod.h"
-
-
 uint8_t justNoise(uint8_t *BitStream, size_t size)
 {
 	static const uint8_t THRESHOLD = 123;
@@ -31,13 +29,13 @@ int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi
 	*high=0;
 	*low=255;
 	// get high and low thresholds 
-	for (int i=0; i < size; i++){
+	for (size_t 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);
+	*high = ((*high-128)*fuzzHi + 12800)/100;
+	*low = ((*low-128)*fuzzLo + 12800)/100;
 	return 1;
 }
 
@@ -83,10 +81,8 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
 	//  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};
@@ -102,11 +98,8 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
 	idx = *startIdx + 9;
 	for (i=0; i<FmtLen; i++){ //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits)
 		parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5);
-		//check even parity
-		if (parityTest(parityBits, 5, 0) == 0){
-			//parity failed quit
-			return 0;
-		}
+		//check even parity - quit if failed
+		if (parityTest(parityBits, 5, 0) == 0) return 0;
 		//set uint64 with ID from BitStream
 		for (uint8_t ii=0; ii<4; ii++){
 			*hi = (*hi << 1) | (*lo >> 63);
@@ -120,185 +113,189 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
 }
 
 //by marshmellow
-//takes 3 arguments - clock, invert, maxErr as integers
-//attempts to demodulate ask while decoding manchester
-//prints binary found and saves in graphbuffer for further commands
-int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr)
+//demodulates strong heavily clipped samples
+int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low)
 {
-	int i;
-	//int clk2=*clk;
-	int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
-	if (*clk==0) return -3;
-	if (start < 0) return -3;
-	// 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
-
-	// 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;
-	//if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
-	if (!maxErr) gLen=*clk*2; 
-	uint8_t errCnt =0;
-	uint16_t MaxBits = 500;
-	uint32_t bestStart = *size;
-	int bestErrCnt = maxErr+1;
-	// 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!!
-
-						//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);
-
+	size_t bitCnt=0, smplCnt=0, errCnt=0;
+	uint8_t waveHigh = 0;
+	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++;
-						lastBit+=*clk;//skip over until hit too many errors
-						if (errCnt>(maxErr)) break;  //allow 1 error for every 1000 samples else start over
+						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
 				}
-				if ((i-iii) >(MaxBits * *clk)) break; //got plenty of 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;
-				}
+			} else { //haven't hit new high or new low yet
+				smplCnt++;
 			}
 		}
 	}
-	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 ((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!!
-
-					//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++;
-					}
+	*size = bitCnt;
+	return errCnt;
+}
 
-					lastBit+=*clk;//skip over error
-				}
-			}
-			if (bitnum >=MaxBits) break;
-		}
-		*size=bitnum;
-	} else{
-		*invert=bestStart;
-		*clk=iii;
-		return -1;
+//by marshmellow
+void askAmp(uint8_t *BitStream, size_t size)
+{
+	for(size_t i = 1; i<size; i++){
+		if (BitStream[i]-BitStream[i-1]>=30) //large jump up
+			BitStream[i]=127;
+		else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down
+			BitStream[i]=-127;
 	}
-	return bestErrCnt;
+	return;
 }
 
 //by marshmellow
-//encode binary data into binary manchester 
-int ManchesterEncode(uint8_t *BitStream, size_t size)
+//attempts to demodulate ask modulations, askType == 0 for ask/raw, askType==1 for ask/manchester
+int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp, uint8_t askType)
 {
-	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;
+	if (*size==0) return -1;
+	int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default
+	if (*clk==0 || start < 0) return -3;
+	if (*invert != 1) *invert = 0;
+	if (amp==1) askAmp(BinStream, *size);
+
+	uint8_t initLoopMax = 255;
+	if (initLoopMax > *size) initLoopMax = *size;
+	// Detect high and lows
+	//25% clip in case highs and lows aren't clipped [marshmellow]
+	int high, low;
+	if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) 
+		return -2; //just noise
+
+	size_t errCnt = 0;
+	// if clean clipped waves detected run alternate demod
+	if (DetectCleanAskWave(BinStream, *size, high, low)) {
+		errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
+		if (askType) //askman
+			return manrawdecode(BinStream, size, 0);	
+		else //askraw
+			return errCnt;
 	}
-	for (; i<(size*2); i++){
-		BitStream[i] = BitStream[i+20000];
+
+	int lastBit;  //set first clock check - can go negative
+	size_t i, bitnum = 0;     //output counter
+	uint8_t midBit = 0;
+	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 MaxBits = 1024;
+	lastBit = start - *clk;
+
+	for (i = start; i < *size; ++i) {
+		if (i-lastBit >= *clk-tol){
+			if (BinStream[i] >= high) {
+				BinStream[bitnum++] = *invert;
+			} else if (BinStream[i] <= low) {
+				BinStream[bitnum++] = *invert ^ 1;
+			} else if (i-lastBit >= *clk+tol) {
+				if (bitnum > 0) {
+					BinStream[bitnum++]=7;
+					errCnt++;						
+				} 
+			} else { //in tolerance - looking for peak
+				continue;
+			}
+			midBit = 0;
+			lastBit += *clk;
+		} else if (i-lastBit >= (*clk/2-tol) && !midBit && !askType){
+			if (BinStream[i] >= high) {
+				BinStream[bitnum++] = *invert;
+			} else if (BinStream[i] <= low) {
+				BinStream[bitnum++] = *invert ^ 1;
+			} else if (i-lastBit >= *clk/2+tol) {
+				BinStream[bitnum] = BinStream[bitnum-1];
+				bitnum++;
+			} else { //in tolerance - looking for peak
+				continue;
+			}
+			midBit = 1;
+		}
+		if (bitnum >= MaxBits) break;
 	}
-	return i;
+	*size = bitnum;
+	return errCnt;
 }
 
 //by marshmellow
 //take 10 and 01 and manchester decode
 //run through 2 times and take least errCnt
-int manrawdecode(uint8_t * BitStream, size_t *size)
+int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert)
 {
 	uint16_t bitnum=0, MaxBits = 512, errCnt = 0;
 	size_t i, ii;
 	uint16_t bestErr = 1000, bestRun = 0;
-	if (size == 0) return -1;
+	if (*size < 16) return -1;
+	//find correct start position [alignment]
 	for (ii=0;ii<2;++ii){
-		i=0;
-		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 {
+		for (i=ii; i<*size-3; i+=2)
+			if (BitStream[i]==BitStream[i+1])
 				errCnt++;
-			}
-			if(bitnum>MaxBits) break;
-		}
+
 		if (bestErr>errCnt){
 			bestErr=errCnt;
 			bestRun=ii;
 		}
 		errCnt=0;
 	}
-	errCnt=bestErr;
-	if (errCnt<20){
-		ii=bestRun;
-		i=0;
-		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 {
-				BitStream[bitnum++]=77;
-				//errCnt++;
-			}
-			if(bitnum>MaxBits) break;
+	//decode
+	for (i=bestRun; i < *size-3; i+=2){
+		if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
+			BitStream[bitnum++]=invert;
+		} else if((BitStream[i] == 0) && BitStream[i+1] == 1){
+			BitStream[bitnum++]=invert^1;
+		} else {
+			BitStream[bitnum++]=7;
 		}
-		*size=bitnum;
+		if(bitnum>MaxBits) break;
 	}
-	return errCnt;
+	*size=bitnum;
+	return bestErr;
+}
+
+//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
@@ -307,9 +304,9 @@ int manrawdecode(uint8_t * BitStream, size_t *size)
 //decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding
 int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert)
 {
-	uint16_t bitnum=0;
-	uint32_t errCnt =0;
-	size_t i=offset;
+	uint16_t bitnum = 0;
+	uint16_t errCnt = 0;
+	size_t i = offset;
 	uint16_t MaxBits=512;
 	//if not enough samples - error
 	if (*size < 51) return -1;
@@ -323,7 +320,7 @@ int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert)
 	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)){
@@ -331,7 +328,7 @@ int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert)
 		} 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;
@@ -340,238 +337,7 @@ int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert)
 	return errCnt;
 }
 
-//by marshmellow
-void askAmp(uint8_t *BitStream, size_t size)
-{
-	int shift = 127;
-	int shiftedVal=0;
-	for(int i = 1; i<size; i++){
-		if (BitStream[i]-BitStream[i-1]>=30) //large jump up
-			shift=127;
-		else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down
-			shift=-127;
-
-		shiftedVal=BitStream[i]+shift;
-
-		if (shiftedVal>255) 
-			shiftedVal=255;
-		else if (shiftedVal<0) 
-			shiftedVal=0;
-		BitStream[i-1] = shiftedVal;
-	}
-	return;
-}
-
-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)
-{
-	uint32_t i;
-	if (*size==0) return -1;
-	int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
-	if (*clk==0) return -1;
-	if (start<0) return -1;
-	if (*invert != 0 && *invert != 1) *invert =0;
-	if (amp==1) askAmp(BinStream, *size);
-
-	uint32_t initLoopMax = 200;
-	if (initLoopMax > *size) initLoopMax=*size;
-	// Detect high and lows
-	//25% clip in case highs and lows aren't clipped [marshmellow]
-	uint8_t clip = 75;
-	int high, low, ans;
-	ans = getHiLo(BinStream, initLoopMax, &high, &low, clip, clip);
-	if (ans<1) return -1; //just noise
-
-	if (DetectCleanAskWave(BinStream, *size, high, low)) {
-		//PrintAndLog("Clean");
-		return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
-	}
-
-	//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=0;    //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;
-	//if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
-	if (!maxErr) gLen = *clk * 2; 
-	uint8_t errCnt =0;
-	uint32_t bestStart = *size;
-	uint32_t bestErrCnt = maxErr; //(*size/1000);
-	uint8_t midBit=0;
-	uint16_t MaxBits=1000;
-
-	//PrintAndLog("DEBUG - lastbit - %d",lastBit);
-	//loop to find first wave that works
-	for (iii=start; 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;
-					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!!
-						//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);
-
-						errCnt++;
-						lastBit+=*clk;//skip over until hit too many errors
-						if (errCnt > maxErr){  
-							//errCnt=0;
-							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;
-				}
-			}
-		}
-	}
-	if (bestErrCnt<=maxErr){
-		//best run is good enough - set to best run and overwrite BinStream
-		iii = bestStart;
-		lastBit = bestStart - *clk;
-		bitnum=0;
-		for (i = iii; i < *size; ++i) {
-			if ((BinStream[i] >= 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!!
-
-					//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++;
-					}
-					lastBit+=*clk;//skip over error
-				}
-			}
-			if (bitnum >= MaxBits) break;
-		}
-		*size=bitnum;
-	} else{
-		*invert=bestStart;
-		*clk=iii;
-		return -1;
-	}
-	return bestErrCnt;
-}
-
+// by marshmellow
 // demod gProxIIDemod 
 // error returns as -x 
 // success returns start position in BitStream
@@ -596,8 +362,8 @@ int gProxII_Demod(uint8_t BitStream[], size_t *size)
 //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;
+	size_t last_transition = 0;
+	size_t idx = 1;
 	//uint32_t maxVal=0;
 	if (fchigh==0) fchigh=10;
 	if (fclow==0) fclow=8;
@@ -626,82 +392,62 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow
 			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
-				dest[numBits]=1;
+				dest[numBits++]=1;
 			} else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage 
 				//do nothing with beginning garbage
 			} else {                                         //9+ = 10 waves
-				dest[numBits]=0;
+				dest[numBits++]=0;
 			}
 			last_transition = idx;
-			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);
-}
-
 //translate 11111100000 to 10
-size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits,
+size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
 		uint8_t invert, uint8_t fchigh, uint8_t fclow)
 {
 	uint8_t lastval=dest[0];
-	uint32_t idx=0;
+	size_t idx=0;
 	size_t numBits=0;
 	uint32_t n=1;
-	float lowWaves = (((float)(rfLen))/((float)fclow));
-	float highWaves = (((float)(rfLen))/((float)fchigh));
 	for( idx=1; idx < size; idx++) {
-
-		if (dest[idx]==lastval) {
-			n++;
-			continue;
-		}
 		n++;
+		if (dest[idx]==lastval) continue; 
+		
 		//if lastval was 1, we have a 1->0 crossing
 		if (dest[idx-1]==1) {
-			if (!numBits && n < (uint8_t)lowWaves) {
+			if (!numBits && n < rfLen/fclow) {
 				n=0;
 				lastval = dest[idx];
 				continue;
 			}
-			n=myround2(((float)n)/lowWaves);
+			n = (n * fclow + rfLen/2) / rfLen;
 		} else {// 0->1 crossing 
 			//test first bitsample too small
-			if (!numBits && n < (uint8_t)highWaves) {
+			if (!numBits && n < rfLen/fchigh) {
 				n=0;
 				lastval = dest[idx];
 				continue;
 			}
-			n = myround2(((float)n)/highWaves);  //-1 for fudge factor
+			n = (n * fchigh + rfLen/2) / rfLen; 
 		}
 		if (n == 0) n = 1;
 
-		if(n < maxConsequtiveBits) //Consecutive
-		{
-			if(invert==0){ //invert bits
-				memset(dest+numBits, dest[idx-1] , n);
-			}else{
-				memset(dest+numBits, dest[idx-1]^1 , n);
-			}
-			numBits += n;
-		}
+		memset(dest+numBits, dest[idx-1]^invert , n);
+		numBits += n;
 		n=0;
 		lastval=dest[idx];
 	}//end for
-
 	// if valid extra bits at the end were all the same frequency - add them in
-	if (n > lowWaves && n > highWaves) {
+	if (n > rfLen/fchigh) {
 		if (dest[idx-2]==1) {
-			n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow));
+			n = (n * fclow + rfLen/2) / rfLen;
 		} else {
-			n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh));  //-1 for fudge factor			
+			n = (n * fchigh + rfLen/2) / rfLen;
 		}
-		memset(dest, dest[idx-1]^invert , n);
+		memset(dest+numBits, dest[idx-1]^invert , n);
 		numBits += n;
 	}
 	return numBits;
@@ -712,7 +458,7 @@ int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t
 {
 	// FSK demodulator
 	size = fsk_wave_demod(dest, size, fchigh, fclow);
-	size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow);
+	size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow);
 	return size;
 }
 
@@ -724,7 +470,7 @@ int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32
 	size_t numStart=0, size2=*size, startIdx=0; 
 	// FSK demodulator
 	*size = fskdemod(dest, size2,50,1,10,8); //fsk2a
-	if (*size < 96) return -2;
+	if (*size < 96*2) 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  
@@ -887,12 +633,13 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size)
 	return (int)startIdx;
 }
 
-
-uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
+// by marshmellow
+// to detect a wave that has heavily clipped (clean) samples
+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) 
@@ -906,52 +653,41 @@ uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
 	return allPeaks;
 }
 
-int DetectStrongAskClock(uint8_t dest[], size_t size)
+// by marshmellow
+// to help detect clocks on heavily clipped samples
+// based on count of low to low
+int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
 {
-	int clk[]={0,8,16,32,40,50,64,100,128,256};
-	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
@@ -960,86 +696,103 @@ 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)
 {
-	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 == 0) return -1;
-	if (size<loopCnt) loopCnt = size;
-	//if we already have a valid clock quit
-	
-	for (;i<8;++i)
-		if (clk[i] == *clock) return 0;
+	size_t i=1;
+	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 <= loopCnt) return -1; //not enough samples
+
+	//if we already have a valid clock
+	uint8_t clockFnd=0;
+	for (;i<clkEnd;++i)
+		if (clk[i] == *clock) clockFnd = i;
+		//clock found but continue to find best startpos
 
 	//get high and low peak
 	int peak, low;
-	getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+	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=7; i>0; i--){
-			if (clk[i] == ans) {
-				*clock=ans;
-				return 0;
+	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]
+				}
 			}
 		}
 	}
-	int ii;
-	int clkCnt;
-	int tol = 0;
-	int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
-	int bestStart[]={0,0,0,0,0,0,0,0,0};
-	int errCnt=0;
+	
+	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;
+
+	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=0; clkCnt < 8; clkCnt++){
-		if (clk[clkCnt] == 32){
+	for(; 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]*2 + tol && clk[clkCnt]<128) loopCnt=clk[clkCnt]*2;
 		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; ii++){
-			if ((dest[ii] >= 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) {
-					*clock = clk[clkCnt];
-					return ii;
-				}
-				//if we found errors see if it is lowest so far and save it as best run
-				if(errCnt<bestErr[clkCnt]){
-					bestErr[clkCnt]=errCnt;
-					bestStart[clkCnt]=ii;
+			if (dest[ii] < peak && dest[ii] > low) continue;
+
+			errCnt=0;
+			// now that we have the first one lined up test rest of wave array
+			loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1;
+			for (i=0; i < loopEnd; ++i){
+				arrLoc = ii + (i * clk[clkCnt]);
+				if (dest[arrLoc] >= peak || dest[arrLoc] <= low){
+				}else if (dest[arrLoc-tol] >= peak || dest[arrLoc-tol] <= low){
+				}else if (dest[arrLoc+tol] >= peak || dest[arrLoc+tol] <= low){
+				}else{  //error no peak detected
+					errCnt++;
 				}
 			}
+			//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<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
+			if(errCnt<bestErr[clkCnt]){
+				bestErr[clkCnt]=errCnt;
+				bestStart[clkCnt]=ii;
+			}
 		}
 	}
-	uint8_t iii=0;
+	uint8_t iii;
 	uint8_t best=0;
-	for (iii=0; iii<8; ++iii){
-		if (bestErr[iii]<bestErr[best]){
-			if (bestErr[iii]==0) bestErr[iii]=1;
+	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 (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
+			if ( (size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii] ){
 				best = iii;
 			}
 		}
 	}
-	if (bestErr[best]>maxErr) return -1;
-	*clock=clk[best];
+	//if (bestErr[best] > maxErr) return -1;
+	if (!clockFnd) *clock = clk[best];
 	return bestStart[best];
 }
 
@@ -1063,7 +816,8 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
 	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);
+	fc = countFC(dest, size, 0);
+	if (fc!=2 && fc!=4 && fc!=8) return -1;
 	//PrintAndLog("DEBUG: FC: %d",fc);
 
 	//find first full wave
@@ -1144,9 +898,9 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
 //detect nrz clock by reading #peaks vs no peaks(or errors)
 int DetectNRZClock(uint8_t dest[], size_t size, int clock)
 {
-	int i=0;
-	int clk[]={8,16,32,40,50,64,100,128,256};
-	int loopCnt = 4096;  //don't need to loop through entire array...
+	size_t i=0;
+	uint8_t clk[]={8,16,32,40,50,64,100,128,255};
+	size_t loopCnt = 4096;  //don't need to loop through entire array...
 	if (size == 0) return 0;
 	if (size<loopCnt) loopCnt = size;
 
@@ -1156,15 +910,15 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock)
 
 	//get high and low peak
 	int peak, low;
-	getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+	if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0;
 
 	//PrintAndLog("DEBUG: peak: %d, low: %d",peak,low);
-	int ii;
+	size_t ii;
 	uint8_t clkCnt;
 	uint8_t tol = 0;
-	int peakcnt=0;
-	int peaksdet[]={0,0,0,0,0,0,0,0};
-	int maxPeak=0;
+	uint16_t peakcnt=0;
+	uint16_t peaksdet[]={0,0,0,0,0,0,0,0};
+	uint16_t maxPeak=0;
 	//test for large clipped waves
 	for (i=0; i<loopCnt; i++){
 		if (dest[i] >= peak || dest[i] <= low){
@@ -1199,7 +953,7 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock)
 		}
 	}
 	int iii=7;
-	int best=0;
+	uint8_t best=0;
 	for (iii=7; iii > 0; iii--){
 		if (peaksdet[iii] > peaksdet[best]){
 			best = iii;
@@ -1217,7 +971,7 @@ void psk1TOpsk2(uint8_t *BitStream, size_t size)
 	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];
@@ -1316,28 +1070,20 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr)
 	if (justNoise(dest, *size)) return -1;
 	*clk = DetectNRZClock(dest, *size, *clk);
 	if (*clk==0) return -2;
-	uint32_t i;
-	uint32_t gLen = 4096;
+	size_t i, gLen = 4096;
 	if (gLen>*size) gLen = *size;
 	int high, low;
 	if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low
 	int lastBit = 0;  //set first clock check
-	uint32_t bitnum = 0;     //output counter
+	size_t iii = 0, bitnum = 0; //bitnum counter
+	uint16_t errCnt = 0, MaxBits = 1000;
+	size_t bestErrCnt = maxErr+1;
+	size_t bestPeakCnt = 0, bestPeakStart = 0;
+	uint8_t bestFirstPeakHigh=0, firstPeakHigh=0, curBit=0, bitHigh=0, errBitHigh=0;
 	uint8_t tol = 1;  //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
-	uint32_t iii = 0;
-	uint16_t errCnt =0;
-	uint16_t MaxBits = 1000;
-	uint32_t bestErrCnt = maxErr+1;
-	uint32_t bestPeakCnt = 0;
-	uint32_t bestPeakStart=0;
-	uint8_t bestFirstPeakHigh=0;
-	uint8_t firstPeakHigh=0;
-	uint8_t curBit=0;
-	uint8_t bitHigh=0;
-	uint8_t errBitHigh=0;
 	uint16_t peakCnt=0;
 	uint8_t ignoreWindow=4;
-	uint8_t ignoreCnt=ignoreWindow; //in case of noice near peak
+	uint8_t ignoreCnt=ignoreWindow; //in case of noise near peak
 	//loop to find first wave that works - align to clock
 	for (iii=0; iii < gLen; ++iii){
 		if ((dest[iii]>=high) || (dest[iii]<=low)){
@@ -1346,135 +1092,93 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr)
 			lastBit=iii-*clk;
 			peakCnt=0;
 			errCnt=0;
-			bitnum=0;
 			//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;
-					bitnum++;
-					peakCnt++;
-					errBitHigh=0;
-					ignoreCnt=ignoreWindow;
-				//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;
-					bitnum++;
-					peakCnt++;
-					errBitHigh=0;
-					ignoreCnt=ignoreWindow;
+				// if we are at a clock bit
+				if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+					//test high/low
+					if (dest[i] >= high || dest[i] <= low) {
+						bitHigh = 1;
+						peakCnt++;
+						errBitHigh = 0;
+						ignoreCnt = ignoreWindow;
+						lastBit += *clk;
+					} else if (i == lastBit + *clk + tol) {
+						lastBit += *clk;
+					}
 				//else if no bars found
-				}else if(dest[i] < high && dest[i] > low) {
+				} else if (dest[i] < high && dest[i] > low){
 					if (ignoreCnt==0){
 						bitHigh=0;
-						if (errBitHigh==1){
-							errCnt++;
-						}
+						if (errBitHigh==1) errCnt++;
 						errBitHigh=0;
 					} else {
 						ignoreCnt--;
 					}
-					//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) && (i<lastBit+*clk-tol || i>lastBit+*clk+tol) && (bitHigh==0)){
+				} else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) {
 					//error bar found no clock...
 					errBitHigh=1;
 				}
-				if (bitnum>=MaxBits) break;
+				if (((i-iii) / *clk)>=MaxBits) break;
 			}
 			//we got more than 64 good bits and not all errors
-			if (bitnum > (64) && (errCnt <= (maxErr))) {
+			if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) {
 				//possible good read
-				if (errCnt == 0){
-					//bestStart = iii;
+				if (!errCnt || peakCnt > bestPeakCnt){
 					bestFirstPeakHigh=firstPeakHigh;
 					bestErrCnt = errCnt;
 					bestPeakCnt = peakCnt;
 					bestPeakStart = iii;
-					break;  //great read - finish
+					if (!errCnt) break;  //great read - finish
 				}
-				if (errCnt < bestErrCnt){  //set this as new best run
-					bestErrCnt = errCnt;
-					//bestStart = iii;
-				}
-				if (peakCnt > bestPeakCnt){
-					bestFirstPeakHigh=firstPeakHigh;
-					bestPeakCnt=peakCnt;
-					bestPeakStart=iii;
-				} 
 			}
 		}
 	}
 	//PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart);
-	if (bestErrCnt <= maxErr){
-		//best run is good enough set to best run and set overwrite BinStream
-		iii=bestPeakStart;
-		lastBit=bestPeakStart-*clk;
-		bitnum=0;
-		memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk);
-		bitnum += (bestPeakStart / *clk);
-		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;
-				bitnum++;
-				errBitHigh=0;
-				ignoreCnt=ignoreWindow;
-			//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;
-				bitnum++;
-				errBitHigh=0;
-				ignoreCnt=ignoreWindow;
-			//else if no bars found
-			}else if(dest[i]<high && dest[i]>low) {
-				if (ignoreCnt==0){
-					bitHigh=0;
-					//if peak is done was it an error peak?
-					if (errBitHigh==1){
-						dest[bitnum]=77;
-						bitnum++;
-						errCnt++;
-					}
-					errBitHigh=0;
-				} else {
-					ignoreCnt--;
-				}
-				//if we are past a clock point
-				if (i>=lastBit+*clk+tol){ //clock val
-					lastBit+=*clk;
-					dest[bitnum]=curBit;
-					bitnum++;
+	if (bestErrCnt > maxErr) return bestErrCnt;		
+
+	//best run is good enough set to best run and set overwrite BinStream
+	lastBit = bestPeakStart - *clk;
+	memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk);
+	bitnum += (bestPeakStart / *clk);
+	for (i = bestPeakStart; i < *size; ++i) {
+		// if expecting a clock bit
+		if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+			// test high/low
+			if (dest[i] >= high || dest[i] <= low) {
+				peakCnt++;
+				bitHigh = 1;
+				errBitHigh = 0;
+				ignoreCnt = ignoreWindow;
+				curBit = *invert;
+				if (dest[i] >= high) curBit ^= 1;
+				dest[bitnum++] = curBit;
+				lastBit += *clk;
+			//else no bars found in clock area
+			} else if (i == lastBit + *clk + tol) {
+				dest[bitnum++] = curBit;
+				lastBit += *clk;
+			}
+		//else if no bars found
+		} else if (dest[i] < high && dest[i] > low){
+			if (ignoreCnt == 0){
+				bitHigh = 0;
+				if (errBitHigh == 1){
+					dest[bitnum++] = 7;
+					errCnt++;
 				}
-			//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) && ((i<lastBit+*clk-tol) || (i>lastBit+*clk+tol)) && (bitHigh==0)){
-				//error bar found no clock...
-				errBitHigh=1;
+				errBitHigh=0;
+			} else {
+				ignoreCnt--;
 			}
-			if (bitnum >= MaxBits) break;
+		} else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) {
+			//error bar found no clock...
+			errBitHigh=1;
 		}
-		*size=bitnum;
-	} else{
-		*size=bitnum;
-		return bestErrCnt;
+		if (bitnum >= MaxBits) break;
 	}
-
-	if (bitnum>16){
-		*size=bitnum;
-	} else return -5;
-	return errCnt;
+	*size = bitnum;
+	return bestErrCnt;
 }
 
 //by marshmellow
@@ -1485,8 +1189,8 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
 	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;
+	uint8_t lastFCcnt = 0;
+	uint16_t fcCounter = 0;
 	uint16_t rfCounter = 0;
 	uint8_t firstBitFnd = 0;
 	size_t i;
@@ -1504,45 +1208,41 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
 			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 ((fcCounter<lastFCcnt || fcCounter>lastFCcnt)){
-				//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;
-						}
+		fcCounter++;
+		rfCounter++;
+
+		if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1]) 
+			continue;		
+		// else new peak 
+		// 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 ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){
+			//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;
+				if (rfCounter > 0 && rfLensFnd < 15){
+					//PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
+					rfCnts[rfLensFnd]++;
+					rfLens[rfLensFnd++] = rfCounter;
+				}
+			} else {
+				firstBitFnd++;
 			}
-			fcCounter=0;
-		} else {
-			// count sample
-			fcCounter++;
-			rfCounter++;
+			rfCounter=0;
+			lastFCcnt=fcCounter;
 		}
+		fcCounter=0;
 	}
 	uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15;
 
@@ -1588,13 +1288,13 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
 //countFC is to detect the field clock lengths.
 //counts and returns the 2 most common wave lengths
 //mainly used for FSK field clock detection
-uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t *mostFC)
+uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
 {
 	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;
+	uint8_t fcCounter = 0;
 	size_t i;
 	if (size == 0) return 0;
 
@@ -1607,13 +1307,14 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t *mostFC)
 		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++;
-
+			if (fskAdj){
+				//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 fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5)
+				if ((fcCounter==9) || fcCounter==4) fcCounter++;
 			// save last field clock count  (fc/xx)
+			lastFCcnt = fcCounter;
+			}
 			// find which fcLens to save it to:
 			for (int ii=0; ii<10; ii++){
 				if (fcLens[ii]==fcCounter){
@@ -1661,89 +1362,31 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t *mostFC)
 		fcL=fcLens[best1];
 	}
 
-	*mostFC=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;
-}
-
-//by marshmellow
-//countPSK_FC is to detect the psk carrier clock length.
-//counts and returns the 1 most common wave length
-uint8_t countPSK_FC(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;
-	uint32_t fcCounter = 0;
-	size_t i;
-	if (size == 0) return 0;
-	
-	// 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++;
-			
-			// 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;
-	uint16_t maxCnt1=0;
-	// go through fclens and find which ones are bigest  
-	for (i=0; i<10; i++){
-		//PrintAndLog("DEBUG: FC %d, Cnt %d",fcLens[i],fcCnts[i]);    
-		// get the best FC value
-		if (fcCnts[i]>maxCnt1) {
-			maxCnt1=fcCnts[i];
-			best1=i;
-		}
-	}
-	return fcLens[best1]; 
+	if (fskAdj) return fcs;	
+	return fcLens[best1];
 }
 
 //by marshmellow - demodulate PSK1 wave 
 //uses wave lengths (# Samples) 
 int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
 {
-	uint16_t loopCnt = 4096;  //don't need to loop through entire array...
 	if (size == 0) return -1;
+	uint16_t loopCnt = 4096;  //don't need to loop through entire array...
 	if (*size<loopCnt) loopCnt = *size;
 
 	uint8_t curPhase = *invert;
 	size_t i, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
 	uint8_t fc=0, fullWaveLen=0, tol=1;
 	uint16_t errCnt=0, waveLenCnt=0;
-	fc = countPSK_FC(dest, *size);
+	fc = countFC(dest, *size, 0);
 	if (fc!=2 && fc!=4 && fc!=8) return -1;
 	//PrintAndLog("DEBUG: FC: %d",fc);
 	*clock = DetectPSKClock(dest, *size, *clock);
-	if (*clock==0) return -1;
+	if (*clock == 0) return -1;
 	int avgWaveVal=0, lastAvgWaveVal=0;
 	//find first phase shift
 	for (i=0; i<loopCnt; i++){
@@ -1756,30 +1399,29 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
 				firstFullWave = waveStart;
 				fullWaveLen=waveLenCnt;
 				//if average wave value is > graph 0 then it is an up wave or a 1
-				if (lastAvgWaveVal > 123) curPhase^=1;  //fudge graph 0 a little 123 vs 128
+				if (lastAvgWaveVal > 123) curPhase ^= 1;  //fudge graph 0 a little 123 vs 128
 				break;
 			} 
 			waveStart = i+1;
 			avgWaveVal = 0;
 		}
-		avgWaveVal+=dest[i+2];
+		avgWaveVal += dest[i+2];
 	}
 	//PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);  
 	lastClkBit = firstFullWave; //set start of wave as clock align
 	//PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit);
 	waveStart = 0;
-	errCnt=0;
 	size_t numBits=0;
 	//set skipped bits
-	memset(dest,curPhase^1,firstFullWave / *clock);
+	memset(dest, curPhase^1, firstFullWave / *clock);
 	numBits += (firstFullWave / *clock);
 	dest[numBits++] = curPhase; //set first read bit
-	for (i = firstFullWave+fullWaveLen-1; i < *size-3; i++){
+	for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
 		//top edge of wave = start of new wave 
 		if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
 			if (waveStart == 0) {
 				waveStart = i+1;
-				waveLenCnt=0;
+				waveLenCnt = 0;
 				avgWaveVal = dest[i+1];
 			} else { //waveEnd
 				waveEnd = i+1;
@@ -1787,27 +1429,27 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
 				lastAvgWaveVal = avgWaveVal/waveLenCnt;
 				if (waveLenCnt > fc){  
 					//PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
-					//if this wave is a phase shift
+					//this wave is a phase shift
 					//PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
 					if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit
-						curPhase^=1;
+						curPhase ^= 1;
 						dest[numBits++] = curPhase;
 						lastClkBit += *clock;
-					} else if (i<lastClkBit+10+fc){
+					} else if (i < lastClkBit+10+fc){
 						//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
 					dest[numBits++] = curPhase;
 				}
-				avgWaveVal=0;
-				waveStart=i+1;
+				avgWaveVal = 0;
+				waveStart = i+1;
 			}
 		}
-		avgWaveVal+=dest[i+1];
+		avgWaveVal += dest[i+1];
 	}
 	*size = numBits;
 	return errCnt;