X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/66707a3b3c59b7ac53231dda726b27389a9bfb70..327a690813ff04d580a2630977f160b8ec809bd9:/common/lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index c77a449a..92ad633e 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -1,439 +1,613 @@
 //-----------------------------------------------------------------------------
-// Copyright (C) 2014 
+// Copyright (C) 2014
 //
 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
 // 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 <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-//#include <inttypes.h>
-//#include <limits.h>
 #include "lfdemod.h"
-//#include "proxmark3.h"
-//#include "data.h"
-//#include "ui.h"
-//#include "graph.h"
-//#include "cmdparser.h"
-//#include "util.h"
-//#include "cmdmain.h"
-//#include "cmddata.h"
-//uint8_t BinStream[MAX_GRAPH_TRACE_LEN];
-//uint8_t BinStreamLen;
+
+
+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 (int 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);
+	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,uint32_t BitLen)
+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=0;
-  uint64_t lo=0; //hi=0,
-
   uint32_t i = 0;
-  uint32_t initLoopMax = 65;
-  if (initLoopMax>BitLen) initLoopMax=BitLen;
-
-  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"); 
+  if (BitStream[1]>1){  //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};
+  // 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};
   uint32_t idx = 0;
-  uint32_t ii=0;
-  uint8_t resetCnt = 0;
-  while( (idx + 64) < BitLen) {
- 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;//sizeof(frame_marker_mask);
-      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){
-            //hi = (hi<<1)|(lo>>31);
-            lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]);
-          }
-          //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;
-        }
-      }
-      //skip last 5 bit parity test for simplicity.
-      return lo;
-    }else{
-      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
+    if (parityTest(parityBits, 5, 0) == 0){
+      //parity failed quit
+    	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
-//takes 2 arguments - clock and invert both as integers
-//attempts to demodulate ask while decoding manchester 
+//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,uint32_t *BitLen,int *clk, int *invert)
+int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr)
 {
-  uint32_t i;
-  //int invert=0;  //invert default
-  int high = 0, low = 0;
-  *clk=DetectClock2(BinStream,(size_t)*BitLen,*clk); //clock default
-  uint8_t BitStream[252] = {0};
-
-  //sscanf(Cmd, "%i %i", &clk, &invert);    
-  if (*clk<8) *clk =64;
-  if (*clk<32) *clk=32;
-  if (*invert != 0 && *invert != 1) *invert=0;
-  uint32_t initLoopMax = 200;
-  if (initLoopMax>*BitLen) initLoopMax=*BitLen;
-  // Detect high and lows 
-  //PrintAndLog("Using Clock: %d  and invert=%d",clk,invert);
-  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 < 30) && ((high !=1)||(low !=-1))){  //throw away static - allow 1 and -1 (in case of threshold command first)
-    //PrintAndLog("no data found"); 
-    return -1;
-  }
-  //13% fuzz in case highs and lows aren't clipped [marshmellow]
-  high=(int)(0.75*high);
-  low=(int)(0.75*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
-  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 = *BitLen;
-  if (gLen > 500) gLen=500;
-  uint8_t errCnt =0;
-  uint32_t bestStart = *BitLen;
-  uint32_t bestErrCnt = (*BitLen/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;    
-      bitnum=0;
-      //loop through to see if this start location works
-      for (i = iii; i < *BitLen; ++i) {   
-        if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){
-          lastBit+=*clk;
-          BitStream[bitnum] =  *invert;
-          bitnum++;
-        } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
-          //low found and we are expecting a bar
-          lastBit+=*clk;
-          BitStream[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){
-              BitStream[bitnum]=77;
-              bitnum++;
-            }
-            
+	// 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!!
 
-            errCnt++;
-            lastBit+=*clk;//skip over until hit too many errors
-            if (errCnt>((*BitLen/1000))){  //allow 1 error for every 1000 samples else start over
-              errCnt=0;
-              bitnum=0;//start over
-              break;
-            }
-          }
-        }
-        if (bitnum >250) break;
-      }
-      //we got more than 64 good bits and not all errors
-      if ((bitnum > (64+errCnt)) && (errCnt<(*BitLen/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 < (*BitLen/1000)) iii=bestStart;
-    }
-  }
-  if (bitnum>16){
-    
-   // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum);
-    //move BitStream back to GraphBuffer
-    //ClearGraph(0);
-    for (i=0; i < bitnum; ++i){
-      BinStream[i]=BitStream[i];
-    }
-    *BitLen=bitnum;
-    //RepaintGraphWindow();
-    //output
-    //if (errCnt>0){
-     // PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt);
-    //}
-   // PrintAndLog("ASK decoded bitstream:");
-    // Now output the bitstream to the scrollback by line of 16 bits
-   // printBitStream2(BitStream,bitnum);
-   // Em410xDecode(Cmd);
-  }  
-  return errCnt;
+						//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)) break;  //allow 1 error for every 1000 samples else start over
+					}
+				}
+				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;
+				}
+			}
+		}
+	}
+	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
+				}
+			}
+			if (bitnum >=MaxBits) break;
+		}
+		*size=bitnum;
+	} else{
+		*invert=bestStart;
+		*clk=iii;
+		return -1;
+	}
+	return bestErrCnt;
+}
+
+//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 10 and 01 and manchester decode
 //run through 2 times and take least errCnt
-int manrawdemod(uint8_t * BitStream, int *bitLen)
-{
-  uint8_t BitStream2[252]={0};
-  int bitnum=0;
-  int errCnt =0;
-  int i=1;
-  int bestErr = 1000;
-  int bestRun = 0;
-  int finish = 0;
-  int ii=1;
-  for (ii=1;ii<3;++ii){
-  	i=1;
-		for (i=i+ii;i<*bitLen-2;i+=2){
-		  if(BitStream[i]==1 && (BitStream[i+1]==0)){
-		    BitStream2[bitnum++]=0;
-		  } else if((BitStream[i]==0)&& BitStream[i+1]==1){
-		    BitStream2[bitnum++]=1;
-	    } else {
-		    BitStream2[bitnum++]=77;
-		      errCnt++;
-	    }
-	    if(bitnum>250) break;
+int manrawdecode(uint8_t * BitStream, size_t *size)
+{
+	uint16_t bitnum=0, MaxBits = 512, errCnt = 0;
+	size_t i, ii;
+	uint16_t bestErr = 1000, bestRun = 0;
+	if (size == 0) return -1;
+	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 {
+				errCnt++;
+			}
+			if(bitnum>MaxBits) break;
 		}
 		if (bestErr>errCnt){
-		  bestErr=errCnt;
-		  bestRun=ii;
-		}	
-		if (ii>1 || finish==1) {
-			if (bestRun==ii) {
-				break;
-			}  else{
-			  ii=bestRun-1;
-		    finish=1;
-		  }	
+			bestErr=errCnt;
+			bestRun=ii;
 		}
 		errCnt=0;
-		bitnum=0;
-  }
-  errCnt=bestErr;
-  if (errCnt<10){
-    for (i=0; i<bitnum;++i){
-      BitStream[i]=BitStream2[i];
-    }  
-    *bitLen=bitnum;
-  }
-  return errCnt;
+	}
+	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;
+		}
+		*size=bitnum;
+	}
+	return errCnt;
+}
+
+//by marshmellow
+//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;
+	uint32_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++]=77;
+			errCnt++;
+		}
+		if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){
+			BitStream[bitnum++]=1^invert;
+		} else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
+			BitStream[bitnum++]=invert;
+		} else {
+			BitStream[bitnum++]=77;
+			errCnt++;
+		}
+		if(bitnum>MaxBits) break;
+	}
+	*size=bitnum;
+	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 2 arguments - clock and invert both as integers
+//takes 3 arguments - clock, invert and maxErr as integers
 //attempts to demodulate ask only
-//prints binary found and saves in graphbuffer for further commands
-int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
+int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp)
 {
-  uint32_t i;
- // int invert=0;  //invert default
-  int high = 0, low = 0;
-  *clk=DetectClock2(BinStream,*bitLen,*clk); //clock default
-  uint8_t BitStream[252] = {0};
-
-  if (*clk<8) *clk =64;
-  if (*clk<32) *clk=32;
-  if (*invert != 0 && *invert != 1) *invert =0;
-  uint32_t initLoopMax = 200;
-  if (initLoopMax>*bitLen) initLoopMax=*bitLen;
-  // 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 < 30) && ((high !=1)||(low !=-1))){  //throw away static - allow 1 and -1 (in case of threshold command first)
- //   PrintAndLog("no data found"); 
-    return -1;
-  }
-  //25% fuzz in case highs and lows aren't clipped [marshmellow]
-  high=(int)(0.75*high);
-  low=(int)(0.75*low);
+	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);
 
-  //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 = *bitLen;
-  if (gLen > 500) gLen=500;
-  uint8_t errCnt =0;
-  uint32_t bestStart = *bitLen;
-  uint32_t bestErrCnt = (*bitLen/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 < *bitLen; ++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++;
-            }
-            
+	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
 
-            errCnt++;
-            lastBit+=*clk;//skip over until hit too many errors
-            if (errCnt>((*bitLen/1000))){  //allow 1 error for every 1000 samples else start over
-              errCnt=0;
-              bitnum=0;//start over
-              break;
-            }
-          }          
-        }
-        if (bitnum>250) break;
-      }
-      //we got more than 64 good bits and not all errors
-      if ((bitnum > (64+errCnt)) && (errCnt<(*bitLen/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 < (*bitLen/1000)) iii=bestStart;
-    }
-  }
-  if (bitnum>16){
-    
-   // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum);
-    //move BitStream back to BinStream
-   // ClearGraph(0);
-    for (i=0; i < bitnum; ++i){
-      BinStream[i]=BitStream[i];
-    }
-    *bitLen=bitnum;
-   // RepaintGraphWindow();
-    //output
-   // if (errCnt>0){
-   //   PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt);
-   // }
-   // PrintAndLog("ASK decoded bitstream:");
-    // Now output the bitstream to the scrollback by line of 16 bits
-   // printBitStream2(BitStream,bitnum);
-    //int errCnt=0;
-    //errCnt=manrawdemod(BitStream,bitnum);
-
- //   Em410xDecode(Cmd);
-  } else return -1;
-  return errCnt;
+	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;
 }
-//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)
+
+// 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};
+
+	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;
+	}
+	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;
-	uint32_t maxVal=0;
-	
-	// we do care about the actual theshold value as sometimes near the center of the
-	// wave we may get static that changes direction of wave for one value
-	// if our value is too low it might affect the read.  and if our tag or
-	// antenna is weak a setting too high might not see anything. [marshmellow]
-	if (size<100) return 0;
-	for(idx=1; idx<100; idx++){
-    	if(maxVal<dest[idx]) maxVal = dest[idx];
-    }
-    // set close to the top of the wave threshold with 13% margin for error
-    // less likely to get a false transition up there. 
-    // (but have to be careful not to go too high and miss some short waves)
-  	uint8_t threshold_value = (uint8_t)(maxVal*.87); 	idx=1;
-		//uint8_t threshold_value = 127;
-	
+	//uint32_t maxVal=0;
+	if (fchigh==0) fchigh=10;
+	if (fclow==0) fclow=8;
+	//set the threshold close to 0 (graph) or 128 std to avoid static
+	uint8_t threshold_value = 123; 
+
 	// sync to first lo-hi transition, and threshold
 
 	// Need to threshold first sample
+
 	if(dest[0] < threshold_value) dest[0] = 0;
 	else dest[0] = 1;
 
@@ -443,16 +617,19 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size)
 	// between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
 	for(idx = 1; idx < size; idx++) {
 		// threshold current value
+
 		if (dest[idx] < threshold_value) dest[idx] = 0;
 		else dest[idx] = 1;
 
 		// Check for 0->1 transition
 		if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition
-			if (idx-last_transition<6){            //0-5 = garbage noise
+			if ((idx-last_transition)<(fclow-2)){            //0-5 = garbage noise
 				//do nothing with extra garbage
-			} else if (idx-last_transition <  9) { //6-8 = 8 waves
+			} else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves
 				dest[numBits]=1;
-			} else {							//9+ = 10 waves
+			} 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;
@@ -464,122 +641,146 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size)
 
 uint32_t myround2(float f)
 {
-  if (f >= 2000) return 2000;//something bad happened
-  return (uint32_t) (f + (float)0.5);
+	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 h2l_crossing_value,uint8_t l2h_crossing_value, 
+//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)
 {
 	uint8_t lastval=dest[0];
 	uint32_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 lastval was 1, we have a 1->0 crossing
-		if ( dest[idx-1]==1 ) {
-			n=myround2((float)(n+1)/((float)(rfLen)/(float)8));
-			//n=(n+1) / h2l_crossing_value;
-		} else {// 0->1 crossing
-			n=myround2((float)(n+1)/((float)(rfLen-2)/(float)10));  //-2 for fudge factor
-			//n=(n+1) / l2h_crossing_value;
+		if (dest[idx-1]==1) {
+			if (!numBits && n < (uint8_t)lowWaves) {
+				n=0;
+				lastval = dest[idx];
+				continue;
+			}
+			n=myround2(((float)n)/lowWaves);
+		} else {// 0->1 crossing 
+			//test first bitsample too small
+			if (!numBits && n < (uint8_t)highWaves) {
+				n=0;
+				lastval = dest[idx];
+				continue;
+			}
+			n = myround2(((float)n)/highWaves);  //-1 for fudge factor
 		}
 		if (n == 0) n = 1;
 
-		if(n < maxConsequtiveBits) //Consecutive 
+		if(n < maxConsequtiveBits) //Consecutive
 		{
-			if(invert==0){ //invert bits 
+			if(invert==0){ //invert bits
 				memset(dest+numBits, dest[idx-1] , n);
 			}else{
-				memset(dest+numBits, dest[idx-1]^1 , n);	
-			}			
+				memset(dest+numBits, dest[idx-1]^1 , 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 (dest[idx-2]==1) {
+			n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow));
+		} else {
+			n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh));  //-1 for fudge factor			
+		}
+		memset(dest, dest[idx-1]^invert , n);
+		numBits += n;
+	}
 	return numBits;
 }
 //by marshmellow  (from holiman's base)
 // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod)
-int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert)
+int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow)
 {
-  //uint8_t h2l_crossing_value = 6;
-  //uint8_t l2h_crossing_value = 5;
-  
-  // if (rfLen==64)  //currently only know settings for RF/64 change from default if option entered
-  // {
-  //   h2l_crossing_value=8;  //or 8  as 64/8 = 8
-  //   l2h_crossing_value=6;  //or 6.4 as 64/10 = 6.4
-  // }
- // size_t size  = GraphTraceLen; 
-    // FSK demodulator
-  size = fsk_wave_demod(dest, size);
-  size = aggregate_bits(dest, size,rfLen,192,invert);
- // size = aggregate_bits(size, h2l_crossing_value, l2h_crossing_value,192, invert); //192=no limit to same values
-  //done messing with GraphBuffer - repaint
-  //RepaintGraphWindow();
-  return size;
+	// FSK demodulator
+	size = fsk_wave_demod(dest, size, fchigh, fclow);
+	size = aggregate_bits(dest, size, rfLen, 192, 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 numStart=0, size2=*size, startIdx=0; 
+  // FSK demodulator
+  *size = fskdemod(dest, size2,50,1,10,8); //fsk2a
+  if (*size < 96) 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 (int)startIdx;
+}
+
+// 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 idx=0; //, found=0; //size=0,
+	size_t numStart=0, size2=*size, startIdx=0;
 	// FSK demodulator
-	size = fskdemod(dest, size,50,0);
-
-	// 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) 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 -1;
+	return (int)startIdx;
 }
 
-uint32_t bytebits_to_byte(uint8_t* src, int numbits)
+uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
 {
 	uint32_t num = 0;
 	for(int i = 0 ; i < numbits ; i++)
@@ -592,103 +793,1022 @@ uint32_t bytebits_to_byte(uint8_t* src, int numbits)
 
 int IOdemodFSK(uint8_t *dest, size_t size)
 {
-  uint32_t idx=0;
+	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);  // FSK2a RF/64 
+	if (size < 65) return -3;  //did we get a good demod?
+	//Index map
+	//0           10          20          30          40          50          60
+	//|           |           |           |           |           |           |
+	//01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
+	//-----------------------------------------------------------------------------
+	//00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11
+	//
+	//XSF(version)facility:codeone+codetwo
+	//Handle the data
+	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), 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 (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;
+}
+
+// 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 < 64) return -1;
+	if (*size < 128*50) return -5;
+
 	//test samples are not just noise
-	uint8_t testMax=0;
-	for(idx=0;idx<64;idx++){
-		if (testMax<dest[idx]) testMax=dest[idx];
-	}
-	idx=0;
-	//if not just noise
-	if (testMax>170){
-		// FSK demodulator
-		size = fskdemod(dest, size,64,1);
-		//Index map
-		//0           10          20          30          40          50          60
-		//|           |           |           |           |           |           |
-		//01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
-		//-----------------------------------------------------------------------------
-		//00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11
-		//
-		//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 - 74); 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;
+	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;
+}
+
+
+uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
+{
+	uint16_t allPeaks=1;
+	uint16_t cntPeaks=0;
+	size_t loopEnd = 572;
+	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;
+}
+
+int DetectStrongAskClock(uint8_t dest[], size_t size)
+{
+	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++;
+			}
 		}
-	}	
-	return 0;
+	}
+	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];
+	}
+	return -1;
 }
 
 // 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 DetectClock2(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=0;
-  int clk[]={16,32,40,50,64,100,128,256};
+  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 clock;
-  if (!peak){
-    for (i=0;i<size;++i){
-      if(dest[i]>peak){
-        peak = dest[i]; 
-      }
-      if(dest[i]<low){
-        low = dest[i];
-      }
-    }
-    peak=(int)(peak*.75);
-    low= (int)(low*.75);
+    if (clk[i] == *clock) return 0;
+
+  //get high and low peak
+  int peak, low;
+  getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+  
+  //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;
+	  	}
+	  }
   }
   int ii;
-  int loopCnt = 256;
-  if (size<loopCnt) loopCnt = size;
   int clkCnt;
   int tol = 0;
-  int bestErr=1000;
-  int errCnt[]={0,0,0,0,0,0,0,0};
-  for(clkCnt=0; clkCnt<6;++clkCnt){
-    if (clk[clkCnt]==32){
+  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;
+  //test each valid clock from smallest to greatest to see which lines up
+  for(clkCnt=0; clkCnt < 8; clkCnt++){
+    if (clk[clkCnt] == 32){
       tol=1;
     }else{
       tol=0;
     }
-    bestErr=1000;
-    for (ii=0; ii<loopCnt; ++ii){
-      if ((dest[ii]>=peak) || (dest[ii]<=low)){
-        errCnt[clkCnt]=0;
-        for (i=0; i<((int)(size/clk[clkCnt])-1); ++i){
+  	if (!maxErr) 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-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 if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
           }else{  //error no peak detected
-            errCnt[clkCnt]++;
-          }    
+            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;
+        }
+      }
+    }
+  }
+  uint8_t iii=0;
+  uint8_t best=0;
+  for (iii=0; iii<8; ++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;
+      }
+    }
+  }
+  if (bestErr[best]>maxErr) return -1;
+  *clock=clk[best];
+  return bestStart[best];
+}
+
+//by marshmellow
+//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;
+
+  size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0;
+  uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1;
+  uint16_t peakcnt=0, errCnt=0, waveLenCnt=0;
+  uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
+  uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0};
+  countFC(dest, size, &fc);
+  //PrintAndLog("DEBUG: FC: %d",fc);
+
+  //find first full wave
+  for (i=0; i<loopCnt; i++){
+    if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
+      if (waveStart == 0) {
+        waveStart = i+1;
+        //PrintAndLog("DEBUG: waveStart: %d",waveStart);
+      } else {
+        waveEnd = i+1;
+        //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+        waveLenCnt = waveEnd-waveStart;
+        if (waveLenCnt > fc){
+          firstFullWave = waveStart;
+          fullWaveLen=waveLenCnt;
+          break;
+        } 
+        waveStart=0;
+      }
+    }
+  }
+  //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
+  
+  //test each valid clock from greatest to smallest to see which lines up
+  for(clkCnt=7; clkCnt >= 1 ; clkCnt--){
+    lastClkBit = firstFullWave; //set end of wave as clock align
+    waveStart = 0;
+    errCnt=0;
+    peakcnt=0;
+    //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit);
+
+    for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){
+      //top edge of wave = start of new wave 
+      if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
+        if (waveStart == 0) {
+          waveStart = i+1;
+          waveLenCnt=0;
+        } else { //waveEnd
+          waveEnd = i+1;
+          waveLenCnt = waveEnd-waveStart;
+          if (waveLenCnt > fc){ 
+            //if this wave is a phase shift
+            //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, ii: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+clk[clkCnt]-tol,ii+1,fc);
+            if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit
+              peakcnt++;
+              lastClkBit+=clk[clkCnt];
+            } else if (i<lastClkBit+8){
+              //noise after a phase shift - ignore
+            } else { //phase shift before supposed to based on clock
+              errCnt++;
+            }
+          } else if (i+1 > lastClkBit + clk[clkCnt] + tol + fc){
+            lastClkBit+=clk[clkCnt]; //no phase shift but clock bit
+          }
+          waveStart=i+1;
+        }
+      }
+    }
+    if (errCnt == 0){
+      return clk[clkCnt];
+    }
+    if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
+    if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt;
+  } 
+  //all tested with errors 
+  //return the highest clk with the most peaks found
+  uint8_t best=7;
+  for (i=7; i>=1; i--){
+    if (peaksdet[i] > peaksdet[best]) {
+      best = i;
+    }
+    //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]);
+  }
+  return clk[best];
+}
+
+//by marshmellow
+//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...
+  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;
+  getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+
+  //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low);
+  int ii;
+  uint8_t clkCnt;
+  uint8_t tol = 0;
+  int peakcnt=0;
+  int peaksdet[]={0,0,0,0,0,0,0,0};
+  int 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)){
+        peakcnt=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){
+            peakcnt++;
+          }
+        }
+        if(peakcnt>peaksdet[clkCnt]) {
+          peaksdet[clkCnt]=peakcnt;
         }
-        if(errCnt[clkCnt]==0) return clk[clkCnt];
-        if(errCnt[clkCnt]<bestErr) bestErr=errCnt[clkCnt];
       }
-    } 
-    errCnt[clkCnt]=bestErr;
+    }
   }
-  int iii=0;
+  int iii=7;
   int best=0;
-  for (iii=0; iii<6;++iii){
-    if (errCnt[iii]<errCnt[best]){
-      best = iii;
+  for (iii=7; iii > 0; iii--){
+    if (peaksdet[iii] > peaksdet[best]){
+    	best = iii;
     }
+    //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]);
   }
   return clk[best];
 }
+
+// by marshmellow
+// convert psk1 demod to psk2 demod
+// only transition waves are 1s
+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){
+			//ignore errors
+		} else if (lastBit!=BitStream[i]){
+			lastBit=BitStream[i];
+			BitStream[i]=1;
+		} else {
+			BitStream[i]=0;
+		}
+	}
+	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
+int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
+{
+	//26 bit 40134 format  (don't know other formats)
+	int i;
+	int long_wait=29;//29 leading zeros in format
+	int start;
+	int first = 0;
+	int first2 = 0;
+	int bitCnt = 0;
+	int ii;
+	// Finding the start of a UID
+	for (start = 0; start <= *size - 250; start++) {
+		first = bitStream[start];
+		for (i = start; i < start + long_wait; i++) {
+			if (bitStream[i] != first) {
+				break;
+			}
+		}
+		if (i == (start + long_wait)) {
+			break;
+		}
+	}
+	if (start == *size - 250 + 1) {
+		// did not find start sequence
+		return -1;
+	}
+	// Inverting signal if needed
+	if (first == 1) {
+		for (i = start; i < *size; i++) {
+			bitStream[i] = !bitStream[i];
+		}
+		*invert = 1;
+	}else *invert=0;
+
+	int iii;
+	//found start once now test length by finding next one
+	for (ii=start+29; ii <= *size - 250; ii++) {
+		first2 = bitStream[ii];
+		for (iii = ii; iii < ii + long_wait; iii++) {
+			if (bitStream[iii] != first2) {
+				break;
+			}
+		}
+		if (iii == (ii + long_wait)) {
+			break;
+		}
+	}
+	if (ii== *size - 250 + 1){
+		// did not find second start sequence
+		return -2;
+	}
+	bitCnt=ii-start;
+
+	// Dumping UID
+	i = start;
+	for (ii = 0; ii < bitCnt; ii++) {
+		bitStream[ii] = bitStream[i++];
+	}
+	*size=bitCnt;
+	return 1;
+}
+
+// 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)
+{
+  if (justNoise(dest, *size)) return -1;
+  *clk = DetectNRZClock(dest, *size, *clk);
+  if (*clk==0) return -2;
+  uint32_t i;
+  uint32_t 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 = 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
+  //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;
+      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;
+        //else if no bars found
+        }else if(dest[i] < high && dest[i] > low) {
+          if (ignoreCnt==0){
+            bitHigh=0;
+            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)){
+          //error bar found no clock...
+          errBitHigh=1;
+        }
+        if (bitnum>=MaxBits) break;
+      }
+      //we got more than 64 good bits and not all errors
+      if (bitnum > (64) && (errCnt <= (maxErr))) {
+        //possible good read
+        if (errCnt == 0){
+          //bestStart = iii;
+          bestFirstPeakHigh=firstPeakHigh;
+          bestErrCnt = errCnt;
+          bestPeakCnt = peakCnt;
+          bestPeakStart = iii;
+          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++;
+        }
+      //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;
+      }
+      if (bitnum >= MaxBits) break;
+    }
+    *size=bitnum;
+  } else{
+    *size=bitnum;
+    return bestErrCnt;
+  }
+
+  if (bitnum>16){
+    *size=bitnum;
+  } else return -5;
+  return errCnt;
+}
+
+//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;
+  uint32_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++){
+    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;
+            }
+          }
+          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;
+    } else {
+      // count sample
+      fcCounter++;
+      rfCounter++;
+    }
+  }
+  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;
+        }
+      }
+    }
+  }
+
+  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 *mostFC)
+{
+  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;
+  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 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++;
+
+      // 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, 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{
+    fcH=fcLens[best2];
+    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]; 
+}
+
+//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;
+  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);
+  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;
+  errCnt=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);
+          //if 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++] = 77;
+          }
+        } 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;
+}