X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/84871873a41a6eb80dd836efdbf4722ffcea089a..b7eddc14db9262a51ad3100ade7386d03500ace8:/common/lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 2352caad..f13a567c 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -5,409 +5,365 @@
 // at your option, any later version. See the LICENSE.txt file for the text of
 // the license.
 //-----------------------------------------------------------------------------
-// Low frequency commands
+// Low frequency demod/decode commands
 //-----------------------------------------------------------------------------
 
 #include <stdlib.h>
 #include <string.h>
 #include "lfdemod.h"
+uint8_t justNoise(uint8_t *BitStream, size_t size)
+{
+	static const uint8_t THRESHOLD = 123;
+	//test samples are not just noise
+	uint8_t justNoise1 = 1;
+	for(size_t idx=0; idx < size && justNoise1 ;idx++){
+		justNoise1 = BitStream[idx] < THRESHOLD;
+	}
+	return justNoise1;
+}
+
+//by marshmellow
+//get high and low values of a wave with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise
+int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo)
+{
+	*high=0;
+	*low=255;
+	// get high and low thresholds 
+	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 = ((*high-128)*fuzzHi + 12800)/100;
+	*low = ((*low-128)*fuzzLo + 12800)/100;
+	return 1;
+}
+
+// by marshmellow
+// pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType
+// returns 1 if passed
+uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType)
+{
+	uint8_t ans = 0;
+	for (uint8_t i = 0; i < bitLen; i++){
+		ans ^= ((bits >> i) & 1);
+	}
+	//PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
+	return (ans == pType);
+}
+
+//by marshmellow
+//search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length
+uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx)
+{
+	uint8_t foundCnt=0;
+	for (int idx=0; idx < *size - pLen; idx++){
+		if (memcmp(BitStream+idx, preamble, pLen) == 0){
+			//first index found
+			foundCnt++;
+			if (foundCnt == 1){
+				*startIdx = idx;
+			}
+			if (foundCnt == 2){
+				*size = idx - *startIdx;
+				return 1;
+			}
+		}
+	}
+	return 0;
+}
 
 //by marshmellow
 //takes 1s and 0s and searches for EM410x format - output EM ID
-uint64_t Em410xDecode(uint8_t *BitStream, size_t size)
+uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
 {
 	//no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
 	//  otherwise could be a void with no arguments
 	//set defaults
-	int high=0, low=255;
-	uint64_t lo=0;
-
 	uint32_t i = 0;
-	uint32_t initLoopMax = 65;
-	if (initLoopMax>size) initLoopMax=size;
+	if (BitStream[1]>1) return 0;  //allow only 1s and 0s
 
-	for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values
-	{
-		if (BitStream[i] > high)
-			high = BitStream[i];
-		else if (BitStream[i] < low)
-			low = BitStream[i];
-	}
-	if (((high !=1)||(low !=0))){  //allow only 1s and 0s
-		// PrintAndLog("no data found");
-		return 0;
-	}
-	uint8_t parityTest=0;
 	// 111111111 bit pattern represent start of frame
-	uint8_t frame_marker_mask[] = {1,1,1,1,1,1,1,1,1};
+	//  include 0 in front to help get start pos
+	uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
 	uint32_t idx = 0;
-	uint32_t ii=0;
-	uint8_t resetCnt = 0;
-	while( (idx + 64) < size) {
- restart:
-		// search for a start of frame marker
-		if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
-		{ // frame marker found
-			idx+=9;
-			for (i=0; i<10;i++){
-				for(ii=0; ii<5; ++ii){
-					parityTest += BitStream[(i*5)+ii+idx];
-				}
-				if (parityTest== ((parityTest>>1)<<1)){
-					parityTest=0;
-					for (ii=0; ii<4;++ii){
-						lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]);
+	uint32_t parityBits = 0;
+	uint8_t errChk = 0;
+	uint8_t FmtLen = 10;
+	*startIdx = 0;
+	errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx);
+	if (errChk == 0 || *size < 64) return 0;
+	if (*size > 64) FmtLen = 22;
+	*startIdx += 1; //get rid of 0 from preamble
+	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 - 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);
+			*lo = (*lo << 1) | (BitStream[(i*5)+ii+idx]);
+		}
+	}
+	if (errChk != 0) return 1;
+	//skip last 5 bit parity test for simplicity.
+	// *size = 64 | 128;
+	return 0;
+}
+
+//by marshmellow
+//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;
+	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;
 					}
-					//PrintAndLog("DEBUG: EM parity passed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d,lo: %d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1],lo);
-				}else {//parity failed
-					//PrintAndLog("DEBUG: EM parity failed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1]);
-					parityTest=0;
-					idx-=8;
-					if (resetCnt>5)return 0;
-					resetCnt++;
-					goto restart;//continue;
+					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++;
 			}
-			//skip last 5 bit parity test for simplicity.
-			return lo;
-		}else{
-			idx++;
 		}
 	}
-	return 0;
+	*size = bitCnt;
+	return errCnt;
 }
 
 //by marshmellow
-//takes 2 arguments - clock and invert both 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)
+void askAmp(uint8_t *BitStream, size_t size)
 {
-	int i;
-	int high = 0, low = 255;
-	*clk=DetectASKClock(BinStream, *size, *clk); //clock default
-
-	if (*clk<8) *clk =64;
-	if (*clk<32) *clk=32;
-	if (*invert != 0 && *invert != 1) *invert=0;
-	uint32_t initLoopMax = 200;
-	if (initLoopMax > *size) initLoopMax=*size;
-	// Detect high and lows
-	for (i = 0; i < initLoopMax; ++i) //200 samples should be enough to find high and low values
-	{
-		if (BinStream[i] > high)
-			high = BinStream[i];
-		else if (BinStream[i] < low)
-			low = BinStream[i];
-	}
-	if ((high < 129) ){  //throw away static (anything < 1 graph)
-		//PrintAndLog("no data found");
-		return -2;
+	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;
 	}
-	//25% fuzz in case highs and lows aren't clipped [marshmellow]
-	high=(int)(((high-128)*.75)+128);
-	low= (int)(((low-128)*.75)+128);
+	return;
+}
 
-	//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;
-	uint8_t errCnt =0;
-	uint32_t bestStart = *size;
-	uint32_t bestErrCnt = (*size/1000);
-	uint32_t maxErr = (*size/1000);
-	//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!!
+//by marshmellow
+//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)
+{
+	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);
 
-						//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);
+	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
 
-						errCnt++;
-						lastBit+=*clk;//skip over until hit too many errors
-						if (errCnt>(maxErr)) break;  //allow 1 error for every 1000 samples else start over
-					}
-				}
-				if ((i-iii) >(400 * *clk)) break; //got plenty of bits
-			}
-			//we got more than 64 good bits and not all errors
-			if ((((i-iii)/ *clk) > (64+errCnt)) && (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;
-				}
-			}
-		}
+	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;
 	}
-	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++;
-					}
 
-					lastBit+=*clk;//skip over error
-				}
+	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;
 			}
-			if (bitnum >=400) break;
+			midBit = 1;
 		}
-		*size=bitnum;
-	} else{
-		*invert=bestStart;
-		*clk=iii;
-		return -1;
+		if (bitnum >= MaxBits) break;
 	}
-	return bestErrCnt;
+	*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 bitnum=0;
-	int errCnt =0;
-	int i=1;
-	int bestErr = 1000;
-	int bestRun = 0;
-	int ii=1;
-	for (ii=1;ii<3;++ii){
-		i=1;
-		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 {
+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 < 16) return -1;
+	//find correct start position [alignment]
+	for (ii=0;ii<2;++ii){
+		for (i=ii; i<*size-3; i+=2)
+			if (BitStream[i]==BitStream[i+1])
 				errCnt++;
-			}
-			if(bitnum>300) break;
-		}
+
 		if (bestErr>errCnt){
 			bestErr=errCnt;
 			bestRun=ii;
 		}
 		errCnt=0;
 	}
-	errCnt=bestErr;
-	if (errCnt<20){
-		ii=bestRun;
-		i=1;
-		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>300) 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
-//take 01 or 10 = 0 and 11 or 00 = 1
-int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset)
-{
-	uint8_t bitnum=0;
-	uint32_t errCnt =0;
-	uint32_t i=1;
-	i=offset;
-	for (;i<*size-2;i+=2){
+//take 01 or 10 = 1 and 11 or 00 = 0
+//check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010
+//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;
+	uint16_t errCnt = 0;
+	size_t i = offset;
+	uint16_t MaxBits=512;
+	//if not enough samples - error
+	if (*size < 51) return -1;
+	//check for phase change faults - skip one sample if faulty
+	uint8_t offsetA = 1, offsetB = 1;
+	for (; i<48; i+=2){
+		if (BitStream[i+1]==BitStream[i+2]) offsetA=0; 
+		if (BitStream[i+2]==BitStream[i+3]) offsetB=0;					
+	}
+	if (!offsetA && offsetB) offset++;
+	for (i=offset; i<*size-3; i+=2){
+		//check for phase error
+		if (BitStream[i+1]==BitStream[i+2]) {
+			BitStream[bitnum++]=7;
+			errCnt++;
+		}
 		if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){
-			BitStream[bitnum++]=1;
+			BitStream[bitnum++]=1^invert;
 		} else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
-			BitStream[bitnum++]=0;
+			BitStream[bitnum++]=invert;
 		} else {
-			BitStream[bitnum++]=77;
+			BitStream[bitnum++]=7;
 			errCnt++;
 		}
-		if(bitnum>250) break;
+		if(bitnum>MaxBits) break;
 	}
 	*size=bitnum;
 	return errCnt;
 }
 
-//by marshmellow
-//takes 2 arguments - clock and invert both as integers
-//attempts to demodulate ask only
-//prints binary found and saves in graphbuffer for further commands
-int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert)
-{
-	uint32_t i;
-	// int invert=0;  //invert default
-	int high = 0, low = 255;
-	*clk=DetectASKClock(BinStream, *size, *clk); //clock default
-	uint8_t BitStream[502] = {0};
-
-	if (*clk<8) *clk =64;
-	if (*clk<32) *clk=32;
-	if (*invert != 0 && *invert != 1) *invert =0;
-	uint32_t initLoopMax = 200;
-	if (initLoopMax > *size) initLoopMax=*size;
-	// Detect high and lows
-	for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values
-	{
-		if (BinStream[i] > high)
-			high = BinStream[i];
-		else if (BinStream[i] < low)
-			low = BinStream[i];
-	}
-	if ((high < 129)){  //throw away static  high has to be more than 0 on graph. 
-													//noise <= -10 here
-		//   PrintAndLog("no data found");
-		return -2;
-	}
-	//25% fuzz in case highs and lows aren't clipped [marshmellow]
-	high=(int)(((high-128)*.75)+128);
-	low= (int)(((low-128)*.75)+128);
-
-	//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=1;    //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;
-	uint8_t errCnt =0;
-	uint32_t bestStart = *size;
-	uint32_t bestErrCnt = (*size/1000);
-	uint8_t midBit=0;
-	//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;
-			//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;
-					BitStream[bitnum] = *invert;
-					bitnum++;
-					midBit=0;
-				} else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
-					//low found and we are expecting a bar
-					lastBit+=*clk;
-					BitStream[bitnum] = 1- *invert;
-					bitnum++;
-					midBit=0;
-				} else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
-					//mid bar?
-					midBit=1;
-					BitStream[bitnum]= 1- *invert;
-					bitnum++;
-				} else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
-					//mid bar?
-					midBit=1;
-					BitStream[bitnum]= *invert;
-					bitnum++;
-				} else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){
-					//no mid bar found
-					midBit=1;
-					BitStream[bitnum]= BitStream[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){
-							BitStream[bitnum]=77;
-							bitnum++;
-						}
+// by marshmellow
+// demod gProxIIDemod 
+// error returns as -x 
+// success returns start position in BitStream
+// BitStream must contain previously askrawdemod and biphasedemoded data
+int gProxII_Demod(uint8_t BitStream[], size_t *size)
+{
+	size_t startIdx=0;
+	uint8_t preamble[] = {1,1,1,1,1,0};
 
-						errCnt++;
-						lastBit+=*clk;//skip over until hit too many errors
-						if (errCnt > ((*size/1000))){  //allow 1 error for every 1000 samples else start over
-							errCnt=0;
-							bitnum=0;//start over
-							break;
-						}
-					}
-				}
-				if (bitnum>500) break;
-			}
-			//we got more than 64 good bits and not all errors
-			if ((bitnum > (64+errCnt)) && (errCnt<(*size/1000))) {
-				//possible good read
-				if (errCnt==0) break;  //great read - finish
-				if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish
-				if (errCnt<bestErrCnt){  //set this as new best run
-					bestErrCnt=errCnt;
-					bestStart = iii;
-				}
-			}
-		}
-		if (iii>=gLen){ //exhausted test
-			//if there was a ok test go back to that one and re-run the best run (then dump after that run)
-			if (bestErrCnt < (*size/1000)) iii=bestStart;
-		}
+	uint8_t errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -3; //preamble not found
+	if (*size != 96) return -2; //should have found 96 bits
+	//check first 6 spacer bits to verify format
+	if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){
+		//confirmed proper separator bits found
+		//return start position
+		return (int) startIdx;
 	}
-	if (bitnum>16){
-		for (i=0; i < bitnum; ++i){
-			BinStream[i]=BitStream[i];
-		}
-		*size=bitnum;
-	} else return -1;
-	return errCnt;
+	return -5;
 }
+
 //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;
@@ -436,58 +392,64 @@ 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;
-			} else {							//9+ = 10 waves
-				dest[numBits]=0;
+				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;
 			}
 			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,
-    uint8_t invert, uint8_t fchigh, uint8_t fclow)
+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;
-
 	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 ) {
-			n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow));
-		} else {// 0->1 crossing
-			n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh));  //-1 for fudge factor
+		if (dest[idx-1]==1) {
+			if (!numBits && n < rfLen/fclow) {
+				n=0;
+				lastval = dest[idx];
+				continue;
+			}
+			n = (n * fclow + rfLen/2) / rfLen;
+		} else {// 0->1 crossing 
+			//test first bitsample too small
+			if (!numBits && n < rfLen/fchigh) {
+				n=0;
+				lastval = dest[idx];
+				continue;
+			}
+			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 > rfLen/fchigh) {
+		if (dest[idx-2]==1) {
+			n = (n * fclow + rfLen/2) / rfLen;
+		} else {
+			n = (n * fchigh + rfLen/2) / rfLen;
+		}
+		memset(dest+numBits, dest[idx-1]^invert , n);
+		numBits += n;
+	}
 	return numBits;
 }
 //by marshmellow  (from holiman's base)
@@ -496,62 +458,75 @@ 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;
 }
+
 // loop to get raw HID waveform then FSK demodulate the TAG ID from it
-int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_t *lo)
+int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo)
 {
+	if (justNoise(dest, *size)) return -1;
 
-	size_t idx=0; //, found=0; //size=0,
+	size_t numStart=0, size2=*size, startIdx=0; 
 	// FSK demodulator
-	size = fskdemod(dest, size,50,0,10,8);
-
-	// final loop, go over previously decoded manchester data and decode into usable tag ID
-	// 111000 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0
-	uint8_t frame_marker_mask[] = {1,1,1,0,0,0};
-	int numshifts = 0;
-	idx = 0;
-	//one scan
-	while( idx + sizeof(frame_marker_mask) < size) {
-		// search for a start of frame marker
-		if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
-		{ // frame marker found
-			idx+=sizeof(frame_marker_mask);
-			while(dest[idx] != dest[idx+1] && idx < size-2)
-			{
-				// Keep going until next frame marker (or error)
-				// Shift in a bit. Start by shifting high registers
-				*hi2 = (*hi2<<1)|(*hi>>31);
-				*hi = (*hi<<1)|(*lo>>31);
-				//Then, shift in a 0 or one into low
-				if (dest[idx] && !dest[idx+1])	// 1 0
-					*lo=(*lo<<1)|0;
-				else // 0 1
-					*lo=(*lo<<1)|1;
-				numshifts++;
-				idx += 2;
-			}
-			// Hopefully, we read a tag and	 hit upon the next frame marker
-			if(idx + sizeof(frame_marker_mask) < size)
-			{
-				if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
-				{
-					//good return
-					return idx;
-				}
-			}
-			// reset
-			*hi2 = *hi = *lo = 0;
-			numshifts = 0;
-		}else	{
-			idx++;
+	*size = fskdemod(dest, size2,50,1,10,8); //fsk2a
+	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  
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -3; //preamble not found
+
+	numStart = startIdx + sizeof(preamble);
+	// final loop, go over previously decoded FSK data and manchester decode into usable tag ID
+	for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){
+		if (dest[idx] == dest[idx+1]){
+			return -4; //not manchester data
 		}
+		*hi2 = (*hi2<<1)|(*hi>>31);
+		*hi = (*hi<<1)|(*lo>>31);
+		//Then, shift in a 0 or one into low
+		if (dest[idx] && !dest[idx+1])  // 1 0
+			*lo=(*lo<<1)|1;
+		else // 0 1
+			*lo=(*lo<<1)|0;
 	}
-	return -1;
+	return (int)startIdx;
 }
 
-uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
+// loop to get raw paradox waveform then FSK demodulate the TAG ID from it
+int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo)
+{
+	if (justNoise(dest, *size)) return -1;
+	
+	size_t numStart=0, size2=*size, startIdx=0;
+	// FSK demodulator
+	*size = fskdemod(dest, size2,50,1,10,8); //fsk2a
+	if (*size < 96) return -2;
+
+	// 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
+	uint8_t preamble[] = {0,0,0,0,1,1,1,1};
+
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -3; //preamble not found
+
+	numStart = startIdx + sizeof(preamble);
+	// final loop, go over previously decoded FSK data and manchester decode into usable tag ID
+	for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){
+		if (dest[idx] == dest[idx+1]) 
+			return -4; //not manchester data
+		*hi2 = (*hi2<<1)|(*hi>>31);
+		*hi = (*hi<<1)|(*lo>>31);
+		//Then, shift in a 0 or one into low
+		if (dest[idx] && !dest[idx+1])	// 1 0
+			*lo=(*lo<<1)|1;
+		else // 0 1
+			*lo=(*lo<<1)|0;
+	}
+	return (int)startIdx;
+}
+
+uint32_t bytebits_to_byte(uint8_t *src, size_t numbits)
 {
 	uint32_t num = 0;
 	for(int i = 0 ; i < numbits ; i++)
@@ -562,22 +537,25 @@ uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
 	return num;
 }
 
-int IOdemodFSK(uint8_t *dest, size_t size)
+//least significant bit first
+uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits)
 {
-	static const uint8_t THRESHOLD = 129;
-	uint32_t idx=0;
-	//make sure buffer has data
-	if (size < 66) return -1;
-	//test samples are not just noise
-	uint8_t justNoise = 1;
-	for(idx=0;idx< size && justNoise ;idx++){
-		justNoise = dest[idx] < THRESHOLD;
+	uint32_t num = 0;
+	for(int i = 0 ; i < numbits ; i++)
+	{
+		num = (num << 1) | *(src + (numbits-(i+1)));
 	}
-	if(justNoise) return 0;
+	return num;
+}
 
+int IOdemodFSK(uint8_t *dest, size_t size)
+{
+	if (justNoise(dest, size)) return -1;
+	//make sure buffer has data
+	if (size < 66*64) return -2;
 	// FSK demodulator
-	size = fskdemod(dest, size, 64, 1, 10, 8);  //  RF/64 and invert
-	if (size < 65) return -1;  //did we get a good demod?
+	size = fskdemod(dest, size, 64, 1, 10, 8);  // FSK2a RF/64 
+	if (size < 65) return -3;  //did we get a good demod?
 	//Index map
 	//0           10          20          30          40          50          60
 	//|           |           |           |           |           |           |
@@ -587,16 +565,155 @@ int IOdemodFSK(uint8_t *dest, size_t size)
 	//
 	//XSF(version)facility:codeone+codetwo
 	//Handle the data
-	uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1};
-	for( idx=0; idx < (size - 65); idx++) {
-		if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
-			//frame marker found
-			if (!dest[idx+8] && dest[idx+17]==1 && dest[idx+26]==1 && dest[idx+35]==1 && dest[idx+44]==1 && dest[idx+53]==1){
-				//confirmed proper separator bits found
-				//return start position
-				return (int) idx;
-			}
+	size_t startIdx = 0;
+	uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1};
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx);
+	if (errChk == 0) return -4; //preamble not found
+
+	if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){
+		//confirmed proper separator bits found
+		//return start position
+		return (int) startIdx;
+	}
+	return -5;
+}
+
+// by marshmellow
+// takes a array of binary values, start position, length of bits per parity (includes parity bit),
+//   Parity Type (1 for odd; 0 for even; 2 for just drop it), and binary Length (length to run) 
+size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen)
+{
+	uint32_t parityWd = 0;
+	size_t j = 0, bitCnt = 0;
+	for (int word = 0; word < (bLen); word+=pLen){
+		for (int bit=0; bit < pLen; bit++){
+			parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
+			BitStream[j++] = (BitStream[startIdx+word+bit]);
 		}
+		j--;
+		// if parity fails then return 0
+		if (pType != 2) {
+			if (parityTest(parityWd, pLen, pType) == 0) return -1;
+		}
+		bitCnt+=(pLen-1);
+		parityWd = 0;
+	}
+	// if we got here then all the parities passed
+	//return ID start index and size
+	return bitCnt;
+}
+
+// Ask/Biphase Demod then try to locate an ISO 11784/85 ID
+// BitStream must contain previously askrawdemod and biphasedemoded data
+int FDXBdemodBI(uint8_t *dest, size_t *size)
+{
+	//make sure buffer has enough data
+	if (*size < 128) return -1;
+
+	size_t startIdx = 0;
+	uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1};
+
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -2; //preamble not found
+	return (int)startIdx;
+}
+
+// by marshmellow
+// FSK Demod then try to locate an AWID ID
+int AWIDdemodFSK(uint8_t *dest, size_t *size)
+{
+	//make sure buffer has enough data
+	if (*size < 96*50) return -1;
+
+	if (justNoise(dest, *size)) return -2;
+
+	// FSK demodulator
+	*size = fskdemod(dest, *size, 50, 1, 10, 8);  // fsk2a RF/50 
+	if (*size < 96) return -3;  //did we get a good demod?
+
+	uint8_t preamble[] = {0,0,0,0,0,0,0,1};
+	size_t startIdx = 0;
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -4; //preamble not found
+	if (*size != 96) return -5;
+	return (int)startIdx;
+}
+
+// by marshmellow
+// FSK Demod then try to locate an Farpointe Data (pyramid) ID
+int PyramiddemodFSK(uint8_t *dest, size_t *size)
+{
+	//make sure buffer has data
+	if (*size < 128*50) return -5;
+
+	//test samples are not just noise
+	if (justNoise(dest, *size)) return -1;
+
+	// FSK demodulator
+	*size = fskdemod(dest, *size, 50, 1, 10, 8);  // fsk2a RF/50 
+	if (*size < 128) return -2;  //did we get a good demod?
+
+	uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
+	size_t startIdx = 0;
+	uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -4; //preamble not found
+	if (*size != 128) return -3;
+	return (int)startIdx;
+}
+
+// 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 = 512+60;
+	if (loopEnd > size) loopEnd = size;
+	for (size_t i=60; i<loopEnd; i++){
+		if (dest[i]>low && dest[i]<high) 
+			allPeaks=0;
+		else
+			cntPeaks++;
+	}
+	if (allPeaks == 0){
+		if (cntPeaks > 300) return 1;
+	}
+	return allPeaks;
+}
+
+// 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)
+{
+	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;
+	}
+	// 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 0;
 }
@@ -604,204 +721,313 @@ int IOdemodFSK(uint8_t *dest, size_t size)
 // by marshmellow
 // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping)
 // maybe somehow adjust peak trimming value based on samples to fix?
-int DetectASKClock(uint8_t dest[], size_t size, int clock)
+// 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 peak=0;
-	int low=255;
-	int clk[]={16,32,40,50,64,100,128,256};
-	int loopCnt = 256;  //don't need to loop through entire array...
-	if (size<loopCnt) loopCnt = size;
+	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 quit
-	for (;i<8;++i)
-		if (clk[i] == clock) return clock;
+	//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
-	for (i=0; i < loopCnt; ++i){
-		if(dest[i] > peak){
-			peak = dest[i];
-		}
-		if(dest[i] < low){
-			low = dest[i];
+	int peak, low;
+	if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1;
+	
+	//test for large clean peaks
+	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]
+				}
+			}
 		}
 	}
-	peak=(int)(((peak-128)*.75)+128);
-	low= (int)(((low-128)*.75)+128);
-	int ii;
-	int clkCnt;
-	int tol = 0;
-	int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000};
-	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 < 6; ++clkCnt){
-		if (clk[clkCnt] == 32){
+	for(; clkCnt < clkEnd; clkCnt++){
+		if (clk[clkCnt] <= 32){
 			tol=1;
 		}else{
 			tol=0;
 		}
+		//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)
-		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/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++;
-					}
+		//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) 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 this is correct one - return this clock
-				if(errCnt==0) return clk[clkCnt];
-				//if we found errors see if it is lowest so far and save it as best run
-				if(errCnt<bestErr[clkCnt]) bestErr[clkCnt]=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;
 			}
 		}
 	}
-	int iii=0;
-	int best=0;
-	for (iii=0; iii<7;++iii){
-		if (bestErr[iii]<bestErr[best]){
-			//                current best bit to error ratio     vs  new bit to error ratio
-			if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
+	uint8_t iii;
+	uint8_t best=0;
+	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] ){
 				best = iii;
 			}
 		}
 	}
-	return clk[best];
+	//if (bestErr[best] > maxErr) return -1;
+	if (!clockFnd) *clock = clk[best];
+	return bestStart[best];
 }
 
 //by marshmellow
-//detect psk clock by reading #peaks vs no peaks(or errors)
-int DetectpskNRZClock(uint8_t dest[], size_t size, int clock)
-{
-	int i=0;
-	int peak=0;
-	int low=255;
-	int clk[]={16,32,40,50,64,100,128,256};
-	int loopCnt = 2048;  //don't need to loop through entire array...
+//detect psk clock by reading each phase shift
+// a phase shift is determined by measuring the sample length of each wave
+int DetectPSKClock(uint8_t dest[], size_t size, int clock)
+{
+	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;
 
-	//get high and low peak
-	for (i=0; i < loopCnt; ++i){
-		if(dest[i] > peak){
-			peak = dest[i];
+	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;
+			}
 		}
-		if(dest[i] < low){
-			low = dest[i];
+	}
+	//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]);
 	}
-	peak=(int)(((peak-128)*.75)+128);
-	low= (int)(((low-128)*.75)+128);
+	return clk[best];
+}
+
+//by marshmellow
+//detect nrz clock by reading #peaks vs no peaks(or errors)
+int DetectNRZClock(uint8_t dest[], size_t size, int clock)
+{
+	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;
+
+	//if we already have a valid clock quit
+	for (; i < 8; ++i)
+		if (clk[i] == clock) return clock;
+
+	//get high and low peak
+	int peak, low;
+	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 errCnt=0;
-	int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
-	int peaksdet[]={0,0,0,0,0,0,0,0,0};
-	//test each valid clock from smallest to greatest to see which lines up
-	for(clkCnt=0; clkCnt < 6; ++clkCnt){
-		if (clk[clkCnt] == 32){
-			tol=1;
-		}else{
-			tol=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){
+			peakcnt++;
+		} else {
+			if (peakcnt>0 && maxPeak < peakcnt){
+				maxPeak = peakcnt;
+			}
+			peakcnt=0;
 		}
+	}
+	peakcnt=0;
+	//test each valid clock from smallest to greatest to see which lines up
+	for(clkCnt=0; clkCnt < 8; ++clkCnt){
+		//ignore clocks smaller than largest peak
+		if (clk[clkCnt]<maxPeak) continue;
+
 		//try lining up the peaks by moving starting point (try first 256)
 		for (ii=0; ii< loopCnt; ++ii){
 			if ((dest[ii] >= peak) || (dest[ii] <= low)){
-				errCnt=0;
 				peakcnt=0;
 				// now that we have the first one lined up test rest of wave array
-				for (i=0; i < ((int)(size/clk[clkCnt])-1); ++i){
+				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){
 						peakcnt++;
-					}else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){
-						peakcnt++;
-					}else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
-						peakcnt++;
-					}else{  //error no peak detected
-						errCnt++;
 					}
 				}
 				if(peakcnt>peaksdet[clkCnt]) {
 					peaksdet[clkCnt]=peakcnt;
-					bestErr[clkCnt]=errCnt;
 				}
 			}
 		}
 	}
-	int iii=0;
-	int best=0;
-	//int ratio2;  //debug
-	int ratio;
-	//int bits;
-	for (iii=0; iii < 7; ++iii){
-		ratio=1000;
-		//ratio2=1000;  //debug
-		//bits=size/clk[iii];  //debug
-		if (peaksdet[iii] > 0){
-			ratio=bestErr[iii]/peaksdet[iii];
-			if (((bestErr[best]/peaksdet[best]) > (ratio)+1)){
-				best = iii;
-			}
-			//ratio2=bits/peaksdet[iii]; //debug
+	int iii=7;
+	uint8_t best=0;
+	for (iii=7; iii > 0; iii--){
+		if (peaksdet[iii] > peaksdet[best]){
+			best = iii;
 		}
-		//PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d, ratio: %d, bits: %d, peakbitr: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best],ratio, bits,ratio2);
+		//PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]);
 	}
 	return clk[best];
 }
 
-//by marshmellow (attempt to get rid of high immediately after a low)
-void pskCleanWave(uint8_t *bitStream, size_t size)
+// by marshmellow
+// convert psk1 demod to psk2 demod
+// only transition waves are 1s
+void psk1TOpsk2(uint8_t *BitStream, size_t size)
 {
-	int i;
-	int low=255;
-	int high=0;
-	int gap = 4;
- // int loopMax = 2048;
-	int newLow=0;
-	int newHigh=0;
-	for (i=0; i < size; ++i){
-		if (bitStream[i] < low) low=bitStream[i];
-		if (bitStream[i] > high) high=bitStream[i];
-	}
-	high = (int)(((high-128)*.80)+128);
-	low = (int)(((low-128)*.90)+128);
-	//low = (uint8_t)(((int)(low)-128)*.80)+128;
-	for (i=0; i < size; ++i){
-		if (newLow == 1){
-			bitStream[i]=low+8;
-			gap--;
-			if (gap == 0){
-				newLow=0;
-				gap=4;
-			}
-		}else if (newHigh == 1){
-			bitStream[i]=high-8;
-			gap--;
-			if (gap == 0){
-				newHigh=0;
-				gap=4;
-			}
+	size_t i=1;
+	uint8_t lastBit=BitStream[0];
+	for (; i<size; i++){
+		if (BitStream[i]==7){
+			//ignore errors
+		} else if (lastBit!=BitStream[i]){
+			lastBit=BitStream[i];
+			BitStream[i]=1;
+		} else {
+			BitStream[i]=0;
 		}
-		if (bitStream[i] <= low) newLow=1;
-		if (bitStream[i] >= high) newHigh=1;
 	}
 	return;
 }
 
+// by marshmellow
+// convert psk2 demod to psk1 demod
+// from only transition waves are 1s to phase shifts change bit
+void psk2TOpsk1(uint8_t *BitStream, size_t size)
+{
+	uint8_t phase=0;
+	for (size_t i=0; i<size; i++){
+		if (BitStream[i]==1){
+			phase ^=1;
+		}
+		BitStream[i]=phase;
+	}
+	return;
+}
 
-//redesigned by marshmellow adjusted from existing decode functions
-//indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
+// redesigned by marshmellow adjusted from existing decode functions
+// indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
 int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
 {
 	//26 bit 40134 format  (don't know other formats)
@@ -864,146 +1090,395 @@ int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
 	return 1;
 }
 
-
-//by marshmellow - demodulate PSK wave or NRZ wave (both similar enough)
-//peaks switch bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
-int pskNRZrawDemod(uint8_t *dest, size_t *size, int *clk, int *invert)
+// by marshmellow - demodulate NRZ wave (both similar enough)
+// peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
+// there probably is a much simpler way to do this.... 
+int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr)
 {
-	pskCleanWave(dest,*size);
-	int clk2 = DetectpskNRZClock(dest, *size, *clk);
-	*clk=clk2;
-	uint32_t i;
-	uint8_t high=0, low=255;
-	uint32_t gLen = *size;
-	if (gLen > 1280) gLen=1280;
-	// get high
-	for (i=0; i < gLen; ++i){
-		if (dest[i] > high) high = dest[i];
-		if (dest[i] < low) low = dest[i];
-	}
-	//fudge high/low bars by 25%
-	high = (uint8_t)((((int)(high)-128)*.75)+128);
-	low = (uint8_t)((((int)(low)-128)*.80)+128);
-
-	//PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
+	if (justNoise(dest, *size)) return -1;
+	*clk = DetectNRZClock(dest, *size, *clk);
+	if (*clk==0) return -2;
+	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
-	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 = 2;    //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;
-	uint8_t errCnt =0;
-	uint32_t bestStart = *size;
-	uint32_t maxErr = (*size/1000);
-	uint32_t bestErrCnt = maxErr;
-	//uint8_t midBit=0;
-	uint8_t curBit=0;
-	uint8_t bitHigh=0;
-	uint8_t ignorewin=*clk/8;
-	//PrintAndLog("DEBUG - lastbit - %d",lastBit);
+	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
+	uint16_t peakCnt=0;
+	uint8_t ignoreWindow=4;
+	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)){
+			if (dest[iii]>=high) firstPeakHigh=1;
+			else firstPeakHigh=0;
 			lastBit=iii-*clk;
+			peakCnt=0;
+			errCnt=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;
-					ignorewin=*clk/8;
-					bitnum++;
-				//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;
-					ignorewin=*clk/8;
-					bitnum++;
+				// 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) {
-					if (ignorewin==0){
+				} else if (dest[i] < high && dest[i] > low){
+					if (ignoreCnt==0){
 						bitHigh=0;
-					}else ignorewin--;
-										//if we are past a clock point
-					if (i >= lastBit+*clk+tol){ //clock val
-						lastBit+=*clk;
-						bitnum++;
+						if (errBitHigh==1) errCnt++;
+						errBitHigh=0;
+					} else {
+						ignoreCnt--;
 					}
-				//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...
-					errCnt++;
+					errBitHigh=1;
 				}
-				if (bitnum>=1000) break;
+				if (((i-iii) / *clk)>=MaxBits) break;
 			}
 			//we got more than 64 good bits and not all errors
-			if ((bitnum > (64+errCnt)) && (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;
-					break;  //great read - finish
+					bestPeakCnt = peakCnt;
+					bestPeakStart = iii;
+					if (!errCnt) break;  //great read - finish
 				}
-				if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish
-				if (errCnt < bestErrCnt){  //set this as new best run
-					bestErrCnt = errCnt;
-					bestStart = iii;
+			}
+		}
+	}
+	//PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart);
+	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++;
 				}
+				errBitHigh=0;
+			} else {
+				ignoreCnt--;
 			}
+		} else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) {
+			//error bar found no clock...
+			errBitHigh=1;
 		}
+		if (bitnum >= MaxBits) break;
 	}
-	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 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;
-				ignorewin=*clk/8;
-				bitnum++;
-			//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;
-				ignorewin=*clk/8;
-				bitnum++;
-			//else if no bars found
-			}else if(dest[i]<high && dest[i]>low) {
-				if (ignorewin==0){
-					bitHigh=0;
-				}else ignorewin--;
-				//if we are past a clock point
-				if (i>=lastBit+*clk+tol){ //clock val
-					lastBit+=*clk;
-					dest[bitnum]=curBit;
-					bitnum++;
+	*size = bitnum;
+	return bestErrCnt;
+}
+
+//by marshmellow
+//detects the bit clock for FSK given the high and low Field Clocks
+uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow)
+{
+	uint8_t clk[] = {8,16,32,40,50,64,100,128,0};
+	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;
+	uint16_t fcCounter = 0;
+	uint16_t rfCounter = 0;
+	uint8_t firstBitFnd = 0;
+	size_t i;
+	if (size == 0) return 0;
+
+	uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2);
+	rfLensFnd=0;
+	fcCounter=0;
+	rfCounter=0;
+	firstBitFnd=0;
+	//PrintAndLog("DEBUG: fcTol: %d",fcTol);
+	// 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++){
+		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;
+		}
+		fcCounter=0;
+	}
+	uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15;
+
+	for (i=0; i<15; i++){
+		//PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]);
+		//get highest 2 RF values  (might need to get more values to compare or compare all?)
+		if (rfCnts[i]>rfCnts[rfHighest]){
+			rfHighest3=rfHighest2;
+			rfHighest2=rfHighest;
+			rfHighest=i;
+		} else if(rfCnts[i]>rfCnts[rfHighest2]){
+			rfHighest3=rfHighest2;
+			rfHighest2=i;
+		} else if(rfCnts[i]>rfCnts[rfHighest3]){
+			rfHighest3=i;
+		}
+	}  
+	// set allowed clock remainder tolerance to be 1 large field clock length+1 
+	//   we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off  
+	uint8_t tol1 = fcHigh+1; 
+	
+	//PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]);
+
+	// loop to find the highest clock that has a remainder less than the tolerance
+	//   compare samples counted divided by
+	int ii=7;
+	for (; ii>=0; ii--){
+		if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){
+			if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){
+				if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){
+					break;
 				}
-			//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...
-				bitHigh=1;
-				dest[bitnum]=77;
-				bitnum++;
-				errCnt++;
 			}
-			if (bitnum >=1000) break;
 		}
-		*size=bitnum;
+	}
+
+	if (ii<0) return 0; // oops we went too far
+
+	return clk[ii];
+}
+
+//by marshmellow
+//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 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;
+	uint8_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++;
+			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){
+					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, best2=9, best3=9;
+	uint16_t maxCnt1=0;
+	// go through fclens and find which ones are bigest 2  
+	for (i=0; i<10; i++){
+		// PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt);    
+		// get the 3 best FC values
+		if (fcCnts[i]>maxCnt1) {
+			best3=best2;
+			best2=best1;
+			maxCnt1=fcCnts[i];
+			best1=i;
+		} else if(fcCnts[i]>fcCnts[best2]){
+			best3=best2;
+			best2=i;
+		} else if(fcCnts[i]>fcCnts[best3]){
+			best3=i;
+		}
+	}
+	uint8_t fcH=0, fcL=0;
+	if (fcLens[best1]>fcLens[best2]){
+		fcH=fcLens[best1];
+		fcL=fcLens[best2];
 	} else{
-		*size=bitnum;
-		*clk=bestStart;
-		return -1;
+		fcH=fcLens[best2];
+		fcL=fcLens[best1];
 	}
 
-	if (bitnum>16){
-		*size=bitnum;
-	} else return -1;
-	return errCnt;
+	// 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]);
+	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)
+{
+	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 = 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;
+	int avgWaveVal=0, lastAvgWaveVal=0;
+	//find first phase shift
+	for (i=0; i<loopCnt; i++){
+		if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
+			waveEnd = i+1;
+			//PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+			waveLenCnt = waveEnd-waveStart;
+			if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave 
+				lastAvgWaveVal = avgWaveVal/(waveLenCnt);
+				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
+				break;
+			} 
+			waveStart = i+1;
+			avgWaveVal = 0;
+		}
+		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;
+	size_t numBits=0;
+	//set skipped bits
+	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++){
+		//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;
+				avgWaveVal = dest[i+1];
+			} else { //waveEnd
+				waveEnd = i+1;
+				waveLenCnt = waveEnd-waveStart;
+				lastAvgWaveVal = avgWaveVal/waveLenCnt;
+				if (waveLenCnt > fc){  
+					//PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
+					//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;
+						dest[numBits++] = curPhase;
+						lastClkBit += *clock;
+					} else if (i < lastClkBit+10+fc){
+						//noise after a phase shift - ignore
+					} else { //phase shift before supposed to based on clock
+						errCnt++;
+						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 += dest[i+1];
+	}
+	*size = numBits;
+	return errCnt;
+}