FIX: removing compiler warning about double const.

[proxmark3-svn] / common / lfdemod.c
diff --git a/common/lfdemod.c b/common/lfdemod.c

index ffa807febf702baf80ff6e48c93037f8d60b0350..ca126df32c696f7be98961c642dd0159397e07b7 100644 (file)
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -7,19 +7,29 @@
  //-----------------------------------------------------------------------------
  // Low frequency demod/decode commands
  //-----------------------------------------------------------------------------
  //-----------------------------------------------------------------------------
  // Low frequency demod/decode commands
  //-----------------------------------------------------------------------------
-
-#include <stdlib.h>
-#include <string.h>
  #include "lfdemod.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;
+
+//un_comment to allow debug print calls when used not on device
+void dummy(char *fmt, ...){}
+
+
+#ifndef ON_DEVICE
+# include "ui.h"
+# include "cmdparser.h"
+# include "cmddata.h"
+# define prnt PrintAndLog
+#else 
+       uint8_t g_debugMode=0;
+# define prnt dummy
+#endif
+
+//test samples are not just noise
+uint8_t justNoise(uint8_t *bits, size_t size) {
+       #define THRESHOLD 123
+       uint8_t val = 1;
+       for(size_t idx=0; idx < size && val ;idx++)
+               val = bits[idx] < THRESHOLD;
+       return val;
  }
  
  //by marshmellow
  }
  
  //by marshmellow
@@ -48,283 +58,196 @@ uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType)
         for (uint8_t i = 0; i < bitLen; i++){
                 ans ^= ((bits >> i) & 1);
         }
         for (uint8_t i = 0; i < bitLen; i++){
                 ans ^= ((bits >> i) & 1);
         }
-       //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
+       if (g_debugMode) prnt("DEBUG: ans: %d, ptype: %d, bits: %08X",ans,pType,bits);
         return (ans == pType);
  }
  
  //by marshmellow
         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)
+// 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 Always 1's; 3 for Always 0's), and binary Length (length to run) 
+size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen)
  {
  {
-       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;
-                       }
+       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]);
                 }
                 }
-       }
-       return 0;
-}
+               if (word+pLen > bLen) break;
  
  
-//by marshmellow
-//takes 1s and 0s and searches for EM410x format - output EM ID
-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
-       uint32_t i = 0;
-       if (BitStream[1]>1){  //allow only 1s and 0s
-               // PrintAndLog("no data found");
-               return 0;
-       }
-       // 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 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]);
+               j--; // overwrite parity with next data
+               // if parity fails then return 0
+               switch (pType) {
+                       case 3:  if (BitStream[j]==1) { return 0; } break; //should be 0 spacer bit
+                       case 2:  if (BitStream[j]==0) { return 0; } break; //should be 1 spacer bit
+                       default: if (parityTest(parityWd, pLen, pType) == 0) { return 0; } break; //test parity
                 }
                 }
+               bitCnt += (pLen-1);
+               parityWd = 0;
         }
         }
-       if (errChk != 0) return 1;
-       //skip last 5 bit parity test for simplicity.
-       // *size = 64 | 128;
-       return 0;
+       // if we got here then all the parities passed
+       //return ID start index and size
+       return bitCnt;
  }
  
  }
  
-//by marshmellow
-//takes 3 arguments - clock, invert, maxErr as integers
-//attempts to demodulate ask while decoding manchester
-//prints binary found and saves in graphbuffer for further commands
-int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr)
+// by marshmellow
+// takes a array of binary values, length of bits per parity (includes parity bit),
+//   Parity Type (1 for odd; 0 for even; 2 Always 1's; 3 Always 0's), and binary Length (length to run)
+//   Make sure *dest is long enough to store original sourceLen + #_of_parities_to_be_added
+size_t addParity(uint8_t *BitSource, uint8_t *dest, uint8_t sourceLen, uint8_t pLen, uint8_t pType)
  {
  {
-       size_t i;
-       int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
-       if (*clk==0 || start < 0) return -3;
-       if (*invert != 1) *invert=0;
-       uint8_t initLoopMax = 255;
-       if (initLoopMax > *size) initLoopMax = *size;
-       // Detect high and lows
-       // 25% fuzz 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
-
-       // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
-       int lastBit = 0;  //set first clock check
-       uint16_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
-       size_t iii = 0;
-       //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
-       if (!maxErr) initLoopMax = *clk * 2; 
-       uint16_t errCnt = 0, MaxBits = 512;
-       uint16_t bestStart = start;
-       uint16_t bestErrCnt = 0;
-       // PrintAndLog("DEBUG - lastbit - %d",lastBit);
-       // if best start position not already found by detect clock then
-       if (start <= 0 || start > initLoopMax){
-               bestErrCnt = maxErr+1;
-               // loop to find first wave that works
-               for (iii=0; iii < initLoopMax; ++iii){
-                       // if no peak skip
-                       if (BinStream[iii] < high && BinStream[iii] > low) continue;
-
-                       lastBit = iii - *clk;
-                       // loop through to see if this start location works
-                       for (i = iii; i < *size; ++i) {
-                               if ((i-lastBit) > (*clk-tol) && (BinStream[i] >= high || BinStream[i] <= low)) {
-                                               lastBit += *clk;
-                               } else if ((i-lastBit) > (*clk+tol)) {
-                                       errCnt++;
-                                       lastBit += *clk;
-                               }
-                               if ((i-iii) > (MaxBits * *clk) || errCnt > maxErr) break; //got plenty of bits or too many errors
-                       }
-                       //we got more than 64 good bits and not all errors
-                       if ((((i-iii)/ *clk) > (64)) && (errCnt<=maxErr)) {
-                               //possible good read
-                               if (!errCnt || errCnt < bestErrCnt){
-                                       bestStart = iii; //set this as new best run
-                                       bestErrCnt = errCnt;
-                                       if (!errCnt) break;  //great read - finish
-                               }
-                       }
-                       errCnt = 0;
+       uint32_t parityWd = 0;
+       size_t j = 0, bitCnt = 0;
+       for (int word = 0; word < sourceLen; word+=pLen-1) {
+               for (int bit=0; bit < pLen-1; bit++){
+                       parityWd = (parityWd << 1) | BitSource[word+bit];
+                       dest[j++] = (BitSource[word+bit]);
                 }
                 }
-       }
-       if (bestErrCnt > maxErr){
-               *invert = bestStart;
-               *clk = iii;
-               return -1;
-       }               
-       //best run is good enough set to best run and set overwrite BinStream
-       lastBit = bestStart - *clk;
-       errCnt = 0;
-       for (i = bestStart; i < *size; ++i) {
-               if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
-                       //high found and we are expecting a bar
-                       lastBit += *clk;
-                       BinStream[bitnum++] = *invert;
-               } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
-                       //low found and we are expecting a bar
-                       lastBit += *clk;
-                       BinStream[bitnum++] = *invert ^ 1;
-               } else if ((i-lastBit)>(*clk+tol)){
-                       //should have hit a high or low based on clock!!
-                       //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-                       if (bitnum > 0) {
-                               BinStream[bitnum++] = 77;
-                               errCnt++;
-                       }               
-                       lastBit += *clk;//skip over error
+               
+               // if parity fails then return 0
+               switch (pType) {
+                       case 3: dest[j++]=0; break; // marker bit which should be a 0
+                       case 2: dest[j++]=1; break; // marker bit which should be a 1
+                       default: 
+                               dest[j++] = parityTest(parityWd, pLen-1, pType) ^ 1;
+                               break;
                 }
                 }
-               if (bitnum >= MaxBits) break;
+               bitCnt += pLen;
+               parityWd = 0;
         }
         }
-       *size = bitnum;
-       return bestErrCnt;
+       // if we got here then all the parities passed
+       //return ID start index and size
+       return bitCnt;
  }
  
  }
  
-//by marshmellow
-//encode binary data into binary manchester 
-int ManchesterEncode(uint8_t *BitStream, size_t size)
+uint32_t bytebits_to_byte(uint8_t *src, size_t numbits)
  {
  {
-       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;
+       uint32_t num = 0;
+       for(int i = 0 ; i < numbits ; i++) {
+               num = (num << 1) | (*src);
+               src++;
         }
         }
-       for (; i<(size*2); i++){
-               BitStream[i] = BitStream[i+20000];
+       return num;
+}
+
+//least significant bit first
+uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits)
+{
+       uint32_t num = 0;
+       for(int i = 0 ; i < numbits ; i++) {
+               num = (num << 1) | *(src + (numbits-(i+1)));
         }
         }
-       return i;
+       return num;
  }
  
  //by marshmellow
  }
  
  //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)
+// search for given preamble in given BitStream and return success=1 or fail=0 and startIndex (where it was found)
+bool preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx){
+       return preambleSearchEx(BitStream, preamble, pLen, size, startIdx, false);
+}
+//by marshmellow
+//search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length
+// param @findone:  look for a repeating preamble or only the first.
+// em4x05/4x69 only sends preamble once, so look for it once in the first pLen bits
+bool preambleSearchEx(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone)
  {
  {
-       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){
-               for (i=ii; i<*size-2; i+=2)
-                       if (BitStream[i]==BitStream[i+1])
-                               errCnt++;
-
-               if (bestErr>errCnt){
-                       bestErr=errCnt;
-                       bestRun=ii;
-               }
-               errCnt=0;
-       }
-       if (bestErr<20){
-               for (i=bestRun; i < *size-2; i+=2){
-                       if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
-                               BitStream[bitnum++]=0;
-                       } else if((BitStream[i] == 0) && BitStream[i+1] == 1){
-                               BitStream[bitnum++]=1;
-                       } else {
-                               BitStream[bitnum++]=77;
+       // Sanity check.  If preamble length is bigger than bitstream length.
+       if ( *size <= pLen ) return false;
+       
+       uint8_t foundCnt = 0;
+       for (int idx = 0; idx < *size - pLen; idx++){
+               if (memcmp(BitStream+idx, preamble, pLen) == 0){
+                       if (g_debugMode) prnt("DEBUG: preamble found at %i", idx);
+                       //first index found
+                       foundCnt++;
+                       if (foundCnt == 1){
+                               *startIdx = idx;
+                               if (findone) return true;
+                       }
+                       if (foundCnt == 2){
+                               *size = idx - *startIdx;
+                               return true;
                         }
                         }
-                       if(bitnum>MaxBits) break;
                 }
                 }
-               *size=bitnum;
         }
         }
-       return bestErr;
+       return false;
  }
  
  }
  
-//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;
-       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++]=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;
+// find start of modulating data (for fsk and psk) in case of beginning noise or slow chip startup.
+size_t findModStart(uint8_t dest[], size_t size, uint8_t threshold_value, uint8_t expWaveSize) {
+       size_t i = 0;
+       size_t waveSizeCnt = 0;
+       uint8_t thresholdCnt = 0;
+       bool isAboveThreshold = dest[i++] >= threshold_value;
+       for (; i < size-20; i++ ) {
+               if(dest[i] < threshold_value && isAboveThreshold) {
+                       thresholdCnt++;
+                       if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break;                     
+                       isAboveThreshold = false;
+                       waveSizeCnt = 0;
+               } else if (dest[i] >= threshold_value && !isAboveThreshold) {
+                       thresholdCnt++;
+                       if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break;                     
+                       isAboveThreshold = true;
+                       waveSizeCnt = 0;
                 } else {
                 } else {
-                       BitStream[bitnum++]=77;
-                       errCnt++;
+                       waveSizeCnt++;
                 }
                 }
-               if(bitnum>MaxBits) break;
+               if (thresholdCnt > 10) break;
         }
         }
-       *size=bitnum;
-       return errCnt;
+       if (g_debugMode == 2) prnt("DEBUG: threshold Count reached at %u, count: %u",i, thresholdCnt);
+       return i;
  }
  
  //by marshmellow
  }
  
  //by marshmellow
-void askAmp(uint8_t *BitStream, size_t size)
+//takes 1s and 0s and searches for EM410x format - output EM ID
+// actually, no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
+uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
  {
  {
-       int shift = 127;
-       int shiftedVal=0;
-       for(size_t 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;
+       // sanity check
+       if (BitStream[1] > 1) return 0; 
+       
+       uint8_t fmtlen;
+       *startIdx = 0;
+       
+       // preamble 0111111111
+       // include 0 in front to help get start pos
+       uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
+       if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx)) 
+               return 0;
+       if (*size < 64) return 0;
+       
+       fmtlen = (*size == 110) ? 22 : 10;
+
+       //skip last 4bit parity row for simplicity
+       *size = removeParity(BitStream, *startIdx + sizeof(preamble), 5, 0, fmtlen * 5);  
+       
+       switch (*size) {
+          case 40: { 
+           // std em410x format
+               *hi = 0;
+               *lo = ((uint64_t)(bytebits_to_byte(BitStream, 8)) << 32) | (bytebits_to_byte(BitStream + 8, 32));
+               break;
+           } 
+           case 88:  { 
+           // long em format
+               *hi = (bytebits_to_byte(BitStream, 24)); 
+               *lo = ((uint64_t)(bytebits_to_byte(BitStream + 24, 32)) << 32) | (bytebits_to_byte(BitStream + 24 + 32, 32));
+               break;
+           } 
+           default: return 0;
+       
+       }
+       return 1;
  }
  
  }
  
-// demodulates strong heavily clipped samples
+//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;
  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++;
         for (size_t i=0; i < *size; i++){
                 if (BinStream[i] >= high && waveHigh){
                         smplCnt++;
@@ -332,10 +255,12 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int
                         smplCnt++;
                 } else { //transition
                         if ((BinStream[i] >= high && !waveHigh) || (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++;
                                 if (smplCnt > clk-(clk/4)-1) { //full clock
                                         if (smplCnt > clk + (clk/4)+1) { //too many samples
                                                 errCnt++;
-                                               BinStream[bitCnt++]=77;
+                                               if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i);
+                                               BinStream[bitCnt++] = 7;
                                         } else if (waveHigh) {
                                                 BinStream[bitCnt++] = invert;
                                                 BinStream[bitCnt++] = invert;
                                         } else if (waveHigh) {
                                                 BinStream[bitCnt++] = invert;
                                                 BinStream[bitCnt++] = invert;
@@ -371,111 +296,86 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int
  }
  
  //by marshmellow
  }
  
  //by marshmellow
-//takes 3 arguments - clock, invert and maxErr as integers
-//attempts to demodulate ask only
-int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp)
+void askAmp(uint8_t *BitStream, size_t size)
+{
+       uint8_t last = 128;
+       for(size_t i = 1; i < size; ++i){
+               if (BitStream[i]-BitStream[i-1] >= 30) //large jump up
+                       last = 255;
+               else if(BitStream[i-1] - BitStream[i] >= 20) //large jump down
+                       last = 0;
+               
+               BitStream[i] = last;
+       }
+}
+
+//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;
  {
         if (*size==0) return -1;
-       int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
-       if (*clk==0 || start < 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);
         if (*invert != 1) *invert = 0;
         if (amp==1) askAmp(BinStream, *size);
+       if (g_debugMode==2) prnt("DEBUG ASK: clk %d, beststart %d, amp %d", *clk, start, amp);
  
         uint8_t initLoopMax = 255;
  
         uint8_t initLoopMax = 255;
-       if (initLoopMax > *size) initLoopMax=*size;
+       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) 
         // 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 -1; //just noise
+               return -2; //just noise
  
  
+       size_t errCnt = 0;
         // if clean clipped waves detected run alternate demod
         // if clean clipped waves detected run alternate demod
-       if (DetectCleanAskWave(BinStream, *size, high, low))
-               return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
+       if (DetectCleanAskWave(BinStream, *size, high, low)) {
+               if (g_debugMode==2) prnt("DEBUG ASK: Clean Wave Detected - using clean wave demod");
+               errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
+               if (askType) //askman
+                       return manrawdecode(BinStream, size, 0);        
+               //askraw
+               return errCnt;
+       }
+       if (g_debugMode==2) prnt("DEBUG ASK: Weak Wave Detected - using weak wave demod");
  
  
-       int lastBit = 0;  //set first clock check - can go negative
-       size_t i, iii = 0;
-       size_t errCnt = 0, bitnum = 0;     //output counter
+       int lastBit;  //set first clock check - can go negative
+       size_t i, bitnum = 0;     //output counter
         uint8_t midBit = 0;
         uint8_t midBit = 0;
-       size_t bestStart = start, bestErrCnt = 0; //(*size/1000);
-       size_t MaxBits = 1024;
-
-       //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
-       if (!maxErr) initLoopMax = *clk * 2; 
-       //if best start not already found by detectclock
-       if (start <= 0 || start > initLoopMax){
-               bestErrCnt = maxErr+1;
-               //PrintAndLog("DEBUG - lastbit - %d",lastBit);
-               //loop to find first wave that works
-               for (iii=0; iii < initLoopMax; ++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 (i-lastBit > *clk && (BinStream[i] >= high || BinStream[i] <= low)){
-                                               lastBit += *clk;
-                                               midBit = 0;
-                                       } else if (i-lastBit > (*clk/2) && midBit == 0) {
-                                               midBit = 1;
-                                       } else if ((i-lastBit) > *clk) {
-                                               //should have hit a high or low based on clock!!
-                                               //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-                                               errCnt++;
-                                               lastBit += *clk;//skip over until hit too many errors
-                                               if (errCnt > maxErr) 
-                                                       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;
-                                       }
-                               }
-                               errCnt=0;
-                       }
-               }
-       }
-       if (bestErrCnt > maxErr){
-               *invert = bestStart;
-               *clk = iii;
-               return -1;
-       }
-       //best run is good enough - set to best run and overwrite BinStream
-       lastBit = bestStart - *clk - 1;
-       errCnt = 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 = 3072;    //max bits to collect
+       lastBit = start - *clk;
  
  
-       for (i = bestStart; i < *size; ++i) {
-               if (i - lastBit > *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;
                         if (BinStream[i] >= high) {
                                 BinStream[bitnum++] = *invert;
                         } else if (BinStream[i] <= low) {
                                 BinStream[bitnum++] = *invert ^ 1;
-                       } else {
+                       } else if (i-lastBit >= *clk+tol) {
                                 if (bitnum > 0) {
                                 if (bitnum > 0) {
-                                       BinStream[bitnum++]=77;
+                                       if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i);
+                                       BinStream[bitnum++]=7;
                                         errCnt++;                                               
                                 } 
                                         errCnt++;                                               
                                 } 
+                       } else { //in tolerance - looking for peak
+                               continue;
                         }
                         midBit = 0;
                         lastBit += *clk;
                         }
                         midBit = 0;
                         lastBit += *clk;
-               } else if (i-lastBit > (*clk/2) && midBit == 0){
+               } 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;
                         if (BinStream[i] >= high) {
                                 BinStream[bitnum++] = *invert;
                         } else if (BinStream[i] <= low) {
                                 BinStream[bitnum++] = *invert ^ 1;
-                       } else {
-
+                       } else if (i-lastBit >= *clk/2+tol) {
                                 BinStream[bitnum] = BinStream[bitnum-1];
                                 bitnum++;
                                 BinStream[bitnum] = BinStream[bitnum-1];
                                 bitnum++;
+                       } else { //in tolerance - looking for peak
+                               continue;
                         }
                         midBit = 1;
                 }
                         }
                         midBit = 1;
                 }
@@ -484,7 +384,107 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max
         *size = bitnum;
         return errCnt;
  }
         *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, uint8_t invert){
+       int errCnt = 0, bestErr = 1000;
+       uint16_t bitnum = 0, MaxBits = 512, bestRun = 0;
+       size_t i, k;
+       if (*size < 16) return -1;
+       //find correct start position [alignment]
+       for (k=0; k < 2; ++k){
+               for (i=k; i<*size-3; i += 2)
+                       if (BitStream[i] == BitStream[i+1])
+                               errCnt++;
+
+               if (bestErr > errCnt){
+                       bestErr = errCnt;
+                       bestRun = k;
+               }
+               errCnt=0;
+       }
+       //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;
+               }
+               if (bitnum>MaxBits) break;
+       }
+       *size=bitnum;
+       return bestErr;
+}
+
+uint32_t manchesterEncode2Bytes(uint16_t datain) {
+       uint32_t output = 0;
+       uint8_t curBit = 0;
+       for (uint8_t i=0; i<16; i++) {
+               curBit = (datain >> (15-i) & 1);
+               output |= (1<<(((15-i)*2)+curBit));
+       }
+       return output;
+}
+
+//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 = 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^invert;
+               } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
+                       BitStream[bitnum++]=invert;
+               } else {
+                       BitStream[bitnum++]=7;
+                       errCnt++;
+               }
+               if(bitnum>MaxBits) break;
+       }
+       *size=bitnum;
+       return errCnt;
+}
  
  
+// by marshmellow
  // demod gProxIIDemod 
  // error returns as -x 
  // success returns start position in BitStream
  // demod gProxIIDemod 
  // error returns as -x 
  // success returns start position in BitStream
@@ -494,55 +494,73 @@ int gProxII_Demod(uint8_t BitStream[], size_t *size)
         size_t startIdx=0;
         uint8_t preamble[] = {1,1,1,1,1,0};
  
         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 (!preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx)) 
+               return -3; //preamble not found
+
         if (*size != 96) return -2; //should have found 96 bits
         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;
         }
         //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;
+       return -5; //spacer bits not found - not a valid gproxII
  }
  
  }
  
-//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
+//translate wave to 11111100000 (1 for each short wave [higher freq] 0 for each long wave [lower freq])
  size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
  {
         size_t last_transition = 0;
         size_t idx = 1;
  size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
  {
         size_t last_transition = 0;
         size_t idx = 1;
-       //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; 
         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; 
+       size_t preLastSample = 0;
+       size_t LastSample = 0;
+       size_t currSample = 0;
+       if ( size < 1024 ) return 0; // not enough samples
  
  
-       // sync to first lo-hi transition, and threshold
+       //find start of modulating data in trace 
+       idx = findModStart(dest, size, threshold_value, fchigh);
  
         // Need to threshold first sample
  
         // Need to threshold first sample
-
-       if(dest[0] < threshold_value) dest[0] = 0;
+       if(dest[idx] < threshold_value) dest[0] = 0;
         else dest[0] = 1;
         else dest[0] = 1;
+       idx++;
  
         size_t numBits = 0;
         // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
  
         size_t numBits = 0;
         // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
-       // or 10 (fc/10) cycles but in practice due to noise etc we may end up with with anywhere
+       // or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere
         // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
         // 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++) {
+       //  (could also be fc/5 && fc/7 for fsk1 = 4-9)
+       for(; idx < size-20; idx++) {
                 // threshold current value
  
                 if (dest[idx] < threshold_value) dest[idx] = 0;
                 else dest[idx] = 1;
  
                 // Check for 0->1 transition
                 // 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)<(fclow-2)){            //0-5 = garbage noise
+               if (dest[idx-1] < dest[idx]) {
+                       preLastSample = LastSample;
+                       LastSample = currSample;
+                       currSample = idx-last_transition;
+                       if (currSample < (fclow-2)){            //0-5 = garbage noise (or 0-3)
                                 //do nothing with extra garbage
                                 //do nothing with extra garbage
-                       } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves
+                       } else if (currSample < (fchigh-1)) {           //6-8 = 8 sample waves  (or 3-6 = 5)
+                               //correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5)
+                               if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1))){
+                                       dest[numBits-1]=1;
+                               }
+                               dest[numBits++]=1;
+
+                       } else if (currSample > (fchigh+1) && numBits < 3) { //12 + and first two bit = unusable garbage
+                               //do nothing with beginning garbage and reset..  should be rare..
+                               numBits = 0; 
+                       } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's (or 4 then a 6 should be two 5's)
                                 dest[numBits++]=1;
                                 dest[numBits++]=1;
-                       } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage 
-                               //do nothing with beginning garbage
-                       } else {                                         //9+ = 10 waves
+                       } else {                                        //9+ = 10 sample waves (or 6+ = 7)
                                 dest[numBits++]=0;
                         }
                         last_transition = idx;
                                 dest[numBits++]=0;
                         }
                         last_transition = idx;
@@ -552,6 +570,7 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow
  }
  
  //translate 11111100000 to 10
  }
  
  //translate 11111100000 to 10
+//rfLen = clock, fchigh = larger field clock, fclow = smaller field clock
  size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
                 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)
  {
@@ -561,27 +580,18 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
         uint32_t n=1;
         for( idx=1; idx < size; idx++) {
                 n++;
         uint32_t n=1;
         for( idx=1; idx < size; idx++) {
                 n++;
-               if (dest[idx]==lastval) continue; 
+               if (dest[idx]==lastval) continue; //skip until we hit a transition
                 
                 
+               //find out how many bits (n) we collected
                 //if lastval was 1, we have a 1->0 crossing
                 if (dest[idx-1]==1) {
                 //if lastval was 1, we have a 1->0 crossing
                 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 
                         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;
  
                         n = (n * fchigh + rfLen/2) / rfLen; 
                 }
                 if (n == 0) n = 1;
  
+               //add to our destination the bits we collected          
                 memset(dest+numBits, dest[idx-1]^invert , n);
                 numBits += n;
                 n=0;
                 memset(dest+numBits, dest[idx-1]^invert , n);
                 numBits += n;
                 n=0;
@@ -599,6 +609,7 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
         }
         return numBits;
  }
         }
         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, uint8_t fchigh, uint8_t fclow)
  //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, uint8_t fchigh, uint8_t fclow)
@@ -614,15 +625,14 @@ int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32
  {
         if (justNoise(dest, *size)) return -1;
  
  {
         if (justNoise(dest, *size)) return -1;
  
-       size_t numStart=0, size2=*size, startIdx=0; 
+       size_t numStart=0, size2 = *size, startIdx=0; 
         // FSK demodulator
         *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};
         // FSK demodulator
         *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
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) 
+               return -3; //preamble not found
  
         numStart = startIdx + sizeof(preamble);
         // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
  
         numStart = startIdx + sizeof(preamble);
         // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
@@ -633,10 +643,11 @@ int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32
                 *hi2 = (*hi2<<1)|(*hi>>31);
                 *hi = (*hi<<1)|(*lo>>31);
                 //Then, shift in a 0 or one into low
                 *hi2 = (*hi2<<1)|(*hi>>31);
                 *hi = (*hi<<1)|(*lo>>31);
                 //Then, shift in a 0 or one into low
+               *lo <<= 1;
                 if (dest[idx] && !dest[idx+1])  // 1 0
                 if (dest[idx] && !dest[idx+1])  // 1 0
-                       *lo=(*lo<<1)|1;
+                       *lo |= 1;
                 else // 0 1
                 else // 0 1
-                       *lo=(*lo<<1)|0;
+                       *lo |= 0;
         }
         return (int)startIdx;
  }
         }
         return (int)startIdx;
  }
@@ -646,16 +657,15 @@ int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, ui
  {
         if (justNoise(dest, *size)) return -1;
         
  {
         if (justNoise(dest, *size)) return -1;
         
-       size_t numStart=0, size2=*size, startIdx=0;
+       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};
         // 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
+       if (preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) 
+               return -3; //preamble not found
  
         numStart = startIdx + sizeof(preamble);
         // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
  
         numStart = startIdx + sizeof(preamble);
         // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
@@ -673,17 +683,6 @@ int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, ui
         return (int)startIdx;
  }
  
         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++)
-       {
-               num = (num << 1) | (*src);
-               src++;
-       }
-       return num;
-}
-
  int IOdemodFSK(uint8_t *dest, size_t size)
  {
         if (justNoise(dest, size)) return -1;
  int IOdemodFSK(uint8_t *dest, size_t size)
  {
         if (justNoise(dest, size)) return -1;
@@ -703,8 +702,8 @@ int IOdemodFSK(uint8_t *dest, size_t size)
         //Handle the data
         size_t startIdx = 0;
         uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1};
         //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 (! preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx))
+               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
  
         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
@@ -715,26 +714,98 @@ int IOdemodFSK(uint8_t *dest, size_t size)
  }
  
  // by marshmellow
  }
  
  // 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;
+// find viking preamble 0xF200 in already demoded data
+int VikingDemod_AM(uint8_t *dest, size_t *size) {
+       //make sure buffer has data
+       if (*size < 64*2) return -2;
+       size_t startIdx = 0;
+       uint8_t preamble[] = {1,1,1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) 
+               return -4; //preamble not found
+       
+       uint32_t checkCalc = bytebits_to_byte(dest+startIdx,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+8,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+16,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+24,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+32,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+40,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+48,8) ^ 
+                                                bytebits_to_byte(dest+startIdx+56,8);
+       if ( checkCalc != 0xA8 ) return -5;     
+       if (*size != 64) return -6;
+       //return start position
+       return (int)startIdx;
+}
+
+// by iceman
+// find Visa2000 preamble in already demoded data
+int Visa2kDemod_AM(uint8_t *dest, size_t *size) {
+       if (*size < 96) return -1; //make sure buffer has data
+       size_t startIdx = 0;
+       uint8_t preamble[] = {0,1,0,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -2; //preamble not found
+       if (*size != 96) return -3; //wrong demoded size
+       //return start position
+       return (int)startIdx;
+}
+// by iceman
+// find Noralsy preamble in already demoded data
+int NoralsyDemod_AM(uint8_t *dest, size_t *size) {
+       if (*size < 96) return -1; //make sure buffer has data
+       size_t startIdx = 0;
+       uint8_t preamble[] = {1,0,1,1,1,0,1,1,0,0,0,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -2; //preamble not found
+       if (*size != 96) return -3; //wrong demoded size
+       //return start position
+       return (int)startIdx;
+}
+// find presco preamble 0x10D in already demoded data
+int PrescoDemod(uint8_t *dest, size_t *size) {
+       if (*size < 128*2) return -1; //make sure buffer has data
+       size_t startIdx = 0;
+       uint8_t preamble[] = {0,0,0,1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -2; //preamble not found
+       if (*size != 128) return -3; //wrong demoded size
+       //return start position
+       return (int)startIdx;
+}
+
+// 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) {
+       if (*size < 128*2) return -1;   //make sure buffer has enough data
+       size_t startIdx = 0;
+       uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -2; //preamble not found
+       if (*size != 128) return -3; //wrong demoded size
+       //return start position
+       return (int)startIdx;
+}
+
+// ASK/Diphase fc/64 (inverted Biphase)
+// Note: this i s not a demod, this is only a detection
+// the parameter *dest needs to be demoded before call
+// 0xFFFF preamble, 64bits
+int JablotronDemod(uint8_t *dest, size_t *size){
+       if (*size < 64*2) return -1;    //make sure buffer has enough data
+       size_t startIdx = 0;
+       uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) 
+               return -2; //preamble not found
+       if (*size != 64) return -3; // wrong demoded size
+       
+       uint8_t checkchksum = 0;
+       for (int i=16; i < 56; i += 8) {
+               checkchksum += bytebits_to_byte(dest+startIdx+i,8);
         }
         }
-       // if we got here then all the parities passed
-       //return ID start index and size
-       return bitCnt;
+       checkchksum ^= 0x3A;
+       uint8_t crc = bytebits_to_byte(dest+startIdx+56, 8);
+       if ( checkchksum != crc ) return -5;
+       return (int)startIdx;
  }
  
  // by marshmellow
  }
  
  // by marshmellow
@@ -752,14 +823,14 @@ int AWIDdemodFSK(uint8_t *dest, size_t *size)
  
         uint8_t preamble[] = {0,0,0,0,0,0,0,1};
         size_t startIdx = 0;
  
         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 (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -4; //preamble not found
         if (*size != 96) return -5;
         return (int)startIdx;
  }
  
  // by marshmellow
         if (*size != 96) return -5;
         return (int)startIdx;
  }
  
  // by marshmellow
-// FSK Demod then try to locate an Farpointe Data (pyramid) ID
+// FSK Demod then try to locate a Farpointe Data (pyramid) ID
  int PyramiddemodFSK(uint8_t *dest, size_t *size)
  {
         //make sure buffer has data
  int PyramiddemodFSK(uint8_t *dest, size_t *size)
  {
         //make sure buffer has data
@@ -771,83 +842,95 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size)
         // FSK demodulator
         *size = fskdemod(dest, *size, 50, 1, 10, 8);  // fsk2a RF/50 
         if (*size < 128) return -2;  //did we get a good demod?
         // 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;
         size_t startIdx = 0;
-       uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
-       if (errChk == 0) return -4; //preamble not found
+       uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -4; //preamble not found
         if (*size != 128) return -3;
         return (int)startIdx;
  }
  
         if (*size != 128) return -3;
         return (int)startIdx;
  }
  
+// find nedap preamble in already demoded data
+int NedapDemod(uint8_t *dest, size_t *size) {
+       //make sure buffer has data
+       if (*size < 128) return -3;
+
+       size_t startIdx = 0;
+       //uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0,0,0,1};
+       uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -4; //preamble not found
+       return (int) startIdx;
+}
+
+// Find IDTEC PSK1, RF  Preamble == 0x4944544B, Demodsize 64bits
+// by iceman
+int IdteckDemodPSK(uint8_t *dest, size_t *size) {
+       //make sure buffer has data
+       if (*size < 64*2) return -1;    
+       size_t startIdx = 0;
+       uint8_t preamble[] = {0,1,0,0,1,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,1,0,1,1};
+       if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+               return -2; //preamble not found
+       if (*size != 64) return -3; // wrong demoded size
+       return (int) startIdx;
+}
  
  
-uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
+// by marshmellow
+// to detect a wave that has heavily clipped (clean) samples
+uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
  {
  {
-       uint16_t allPeaks=1;
+       bool allArePeaks = true;
         uint16_t cntPeaks=0;
         uint16_t cntPeaks=0;
-       size_t loopEnd = 572;
+       size_t loopEnd = 512+160;
         if (loopEnd > size) loopEnd = size;
         if (loopEnd > size) loopEnd = size;
-       for (size_t i=60; i<loopEnd; i++){
+       for (size_t i=160; i<loopEnd; i++){
                 if (dest[i]>low && dest[i]<high) 
                 if (dest[i]>low && dest[i]<high) 
-                       allPeaks=0;
+                       allArePeaks = false;
                 else
                         cntPeaks++;
         }
                 else
                         cntPeaks++;
         }
-       if (allPeaks == 0){
-               if (cntPeaks > 300) return 1;
+       if (!allArePeaks){
+               if (cntPeaks > 300) return true;
         }
         }
-       return allPeaks;
+       return allArePeaks;
  }
  }
-
  // by marshmellow
  // to help detect clocks on heavily clipped samples
  // by marshmellow
  // to help detect clocks on heavily clipped samples
-// based on counts between zero crossings
-int DetectStrongAskClock(uint8_t dest[], size_t size)
+// based on count of low to low
+int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
  {
  {
-       int clk[]={0,8,16,32,40,50,64,100,128};
-       size_t idx = 40;
-       uint8_t high=0;
-       size_t cnt = 0;
-       size_t highCnt = 0;
-       size_t highCnt2 = 0;
-       for (;idx < size; idx++){
-               if (dest[idx]>128) {
-                       if (!high){
-                               high=1;
-                               if (cnt > highCnt){
-                                       if (highCnt != 0) highCnt2 = highCnt;
-                                       highCnt = cnt;
-                               } else if (cnt > highCnt2) {
-                                       highCnt2 = cnt;
-                               }
-                               cnt=1;
-                       } else {
-                               cnt++;
-                       }
-               } else if (dest[idx] <= 128){
-                       if (high) {
-                               high=0;
-                               if (cnt > highCnt) {
-                                       if (highCnt != 0) highCnt2 = highCnt;
-                                       highCnt = cnt;
-                               } else if (cnt > highCnt2) {
-                                       highCnt2 = cnt;
-                               }
-                               cnt=1;
-                       } else {
-                               cnt++;
-                       }
-               }
+       uint8_t fndClk[] = {8,16,32,40,50,64,128};
+       size_t startwave;
+       size_t i = 100;
+       size_t minClk = 255;
+               // get to first full low to prime loop and skip incomplete first pulse
+       while ((dest[i] < high) && (i < size))
+               ++i;
+       while ((dest[i] > low) && (i < size))
+               ++i;
+
+       // loop through all samples
+       while (i < size) {
+               // measure from low to low
+               while ((dest[i] > low) && (i < size))
+                       ++i;
+               startwave= i;
+               while ((dest[i] < high) && (i < size))
+                       ++i;
+               while ((dest[i] > low) && (i < size))
+                       ++i;
+               //get minimum measured distance
+               if (i-startwave < minClk && i < size)
+                       minClk = i - startwave;
         }
         }
-       uint8_t tol;
-       for (idx=8; idx>0; idx--){
-               tol = clk[idx]/8;
-               if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol)
-                       return clk[idx];
-               if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol)
-                       return clk[idx];
+       // set clock
+       if (g_debugMode==2) prnt("DEBUG ASK: detectstrongASKclk smallest wave: %d",minClk);
+       for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
+               if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1)
+                       return fndClk[clkCnt];
         }
         }
-       return -1;
+       return 0;
  }
  
  // by marshmellow
  }
  
  // by marshmellow
@@ -856,26 +939,34 @@ int DetectStrongAskClock(uint8_t dest[], size_t size)
  // return start index of best starting position for that clock and return clock (by reference)
  int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
  {
  // 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)
  {
-       size_t i=0;
-       uint8_t clk[]={8,16,32,40,50,64,100,128,255};
+       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...
         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 0;
+       if (size <= loopCnt+60) return -1; //not enough samples
+       size -= 60; //sometimes there is a strange end wave - filter out this....
+       //if we already have a valid clock
+       uint8_t clockFnd=0;
+       for (;i<clkEnd;++i)
+               if (clk[i] == *clock) clockFnd = i;
+               //clock found but continue to find best startpos
  
         //get high and low peak
         int peak, low;
         if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1;
         
         //test for large clean peaks
  
         //get high and low peak
         int peak, low;
         if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1;
         
         //test for large clean peaks
-       if (DetectCleanAskWave(dest, size, peak, low)==1){
-               int ans = DetectStrongAskClock(dest, size);
-               for (i=7; i>0; i--){
-                       if (clk[i] == ans) {
-                               *clock = ans;
-                               return 0;
+       if (!clockFnd){
+               if (DetectCleanAskWave(dest, size, peak, low)==1){
+                       int ans = DetectStrongAskClock(dest, size, peak, low);
+                       if (g_debugMode==2) prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %d",ans);
+                       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]
+                               }
                         }
                 }
         }
                         }
                 }
         }
@@ -885,20 +976,32 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
         uint8_t bestStart[]={0,0,0,0,0,0,0,0,0};
         size_t errCnt = 0;
         size_t arrLoc, loopEnd;
         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
         //test each valid clock from smallest to greatest to see which lines up
-       for(clkCnt=0; clkCnt < 8; clkCnt++){
-               if (clk[clkCnt] == 32){
+       for(; clkCnt < clkEnd; clkCnt++) {
+               if (clk[clkCnt] <= 32) {
                         tol=1;
                         tol=1;
-               }else{
+               } else {
                         tol=0;
                 }
                         tol=0;
                 }
-               if (!maxErr) loopCnt=clk[clkCnt]*2;
-               bestErr[clkCnt]=1000;
-               //try lining up the peaks by moving starting point (try first 256)
+               //if no errors allowed - keep start within the first clock
+               if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) 
+                       loopCnt = clk[clkCnt] * 2;
+
+               bestErr[clkCnt] = 1000;
+
+               //try lining up the peaks by moving starting point (try first few clocks)
                 for (ii=0; ii < loopCnt; ii++){
                         if (dest[ii] < peak && dest[ii] > low) continue;
  
                 for (ii=0; ii < loopCnt; ii++){
                         if (dest[ii] < peak && dest[ii] > low) continue;
  
-                       errCnt=0;
+                       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){
                         // 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){
@@ -910,33 +1013,33 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
                                         errCnt++;
                                 }
                         }
                                         errCnt++;
                                 }
                         }
-                       //if we found no errors then we can stop here
+                       //if we found no errors then we can stop here and a low clock (common clocks)
                         //  this is correct one - return this clock
                         //  this is correct one - return this clock
-                                       //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i);
-                       if(errCnt==0 && clkCnt<6) {
-                               *clock = clk[clkCnt];
+                       if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %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
                                 return ii;
                         }
                         //if we found errors see if it is lowest so far and save it as best run
-                       if(errCnt<bestErr[clkCnt]){
-                               bestErr[clkCnt]=errCnt;
-                               bestStart[clkCnt]=ii;
+                       if (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;
+       uint8_t k;
+       uint8_t best = 0;
+       for (k=1; k < clkEnd; ++k){
+               if (bestErr[k] < bestErr[best]){
+                       if (bestErr[k] == 0) bestErr[k]=1;
                         // current best bit to error ratio     vs  new bit to error ratio
                         // 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 ( (size/clk[best])/bestErr[best] < (size/clk[k])/bestErr[k] ){
+                               best = k;
                         }
                 }
                         }
                 }
+               if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]);
         }
         }
-       if (bestErr[best] > maxErr) return -1;
-       *clock = clk[best];
+       if (!clockFnd) *clock = clk[best];
         return bestStart[best];
  }
  
         return bestStart[best];
  }
  
@@ -948,7 +1051,7 @@ 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;
         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 (size<loopCnt) loopCnt = size-20;
  
         //if we already have a valid clock quit
         size_t i=1;
  
         //if we already have a valid clock quit
         size_t i=1;
@@ -962,17 +1065,17 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
         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;
         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);
+       if (g_debugMode==2) prnt("DEBUG PSK: FC: %d",fc);
  
         //find first full wave
  
         //find first full wave
-       for (i=0; i<loopCnt; i++){
+       for (i=160; i<loopCnt; i++){
                 if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
                         if (waveStart == 0) {
                                 waveStart = i+1;
                 if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
                         if (waveStart == 0) {
                                 waveStart = i+1;
-                               //PrintAndLog("DEBUG: waveStart: %d",waveStart);
+                               //prnt("DEBUG: waveStart: %d",waveStart);
                         } else {
                                 waveEnd = i+1;
                         } else {
                                 waveEnd = i+1;
-                               //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+                               //prnt("DEBUG: waveEnd: %d",waveEnd);
                                 waveLenCnt = waveEnd-waveStart;
                                 if (waveLenCnt > fc){
                                         firstFullWave = waveStart;
                                 waveLenCnt = waveEnd-waveStart;
                                 if (waveLenCnt > fc){
                                         firstFullWave = waveStart;
@@ -983,7 +1086,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
                         }
                 }
         }
                         }
                 }
         }
-       //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
+       if (g_debugMode ==2) prnt("DEBUG PSK: 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--){
         
         //test each valid clock from greatest to smallest to see which lines up
         for(clkCnt=7; clkCnt >= 1 ; clkCnt--){
@@ -991,7 +1094,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
                 waveStart = 0;
                 errCnt=0;
                 peakcnt=0;
                 waveStart = 0;
                 errCnt=0;
                 peakcnt=0;
-               //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit);
+               if (g_debugMode == 2) prnt("DEBUG PSK: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit);
  
                 for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){
                         //top edge of wave = start of new wave 
  
                 for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){
                         //top edge of wave = start of new wave 
@@ -1004,7 +1107,7 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
                                         waveLenCnt = waveEnd-waveStart;
                                         if (waveLenCnt > fc){ 
                                                 //if this wave is a phase shift
                                         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 (g_debugMode == 2) prnt("DEBUG PSK: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+clk[clkCnt]-tol,i+1,fc);
                                                 if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit
                                                         peakcnt++;
                                                         lastClkBit+=clk[clkCnt];
                                                 if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit
                                                         peakcnt++;
                                                         lastClkBit+=clk[clkCnt];
@@ -1033,11 +1136,40 @@ int DetectPSKClock(uint8_t dest[], size_t size, int clock)
                 if (peaksdet[i] > peaksdet[best]) {
                         best = 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]);
+               if (g_debugMode == 2) prnt("DEBUG PSK: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[i],peaksdet[i],bestErr[i],clk[best]);
         }
         return clk[best];
  }
  
         }
         return clk[best];
  }
  
+int DetectStrongNRZClk(uint8_t *dest, size_t size, int peak, int low){
+       //find shortest transition from high to low
+       size_t i = 0;
+       size_t transition1 = 0;
+       int lowestTransition = 255;
+       bool lastWasHigh = false;
+
+       //find first valid beginning of a high or low wave
+       while ((dest[i] >= peak || dest[i] <= low) && (i < size))
+               ++i;
+       while ((dest[i] < peak && dest[i] > low) && (i < size))
+               ++i;
+       lastWasHigh = (dest[i] >= peak);
+
+       if (i==size) return 0;
+       transition1 = i;
+
+       for (;i < size; i++) {
+               if ((dest[i] >= peak && !lastWasHigh) || (dest[i] <= low && lastWasHigh)) {
+                       lastWasHigh = (dest[i] >= peak);
+                       if (i-transition1 < lowestTransition) lowestTransition = i-transition1;
+                       transition1 = i;
+               }
+       }
+       if (lowestTransition == 255) lowestTransition = 0;
+       if (g_debugMode==2) prnt("DEBUG NRZ: detectstrongNRZclk smallest wave: %d",lowestTransition);
+       return lowestTransition;
+}
+
  //by marshmellow
  //detect nrz clock by reading #peaks vs no peaks(or errors)
  int DetectNRZClock(uint8_t dest[], size_t size, int clock)
  //by marshmellow
  //detect nrz clock by reading #peaks vs no peaks(or errors)
  int DetectNRZClock(uint8_t dest[], size_t size, int clock)
@@ -1046,8 +1178,7 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock)
         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;
         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 (size<loopCnt) loopCnt = size-20;
         //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 quit
         for (; i < 8; ++i)
                 if (clk[i] == clock) return clock;
@@ -1056,38 +1187,82 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock)
         int peak, low;
         if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0;
  
         int peak, low;
         if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0;
  
-       //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low);
+       int lowestTransition = DetectStrongNRZClk(dest, size-20, peak, low);
         size_t ii;
         uint8_t clkCnt;
         uint8_t tol = 0;
         size_t ii;
         uint8_t clkCnt;
         uint8_t tol = 0;
-       uint16_t peakcnt=0;
-       uint16_t peaksdet[]={0,0,0,0,0,0,0,0};
-       uint16_t maxPeak=0;
+       uint16_t smplCnt = 0;
+       int16_t peakcnt = 0;
+       int16_t peaksdet[] = {0,0,0,0,0,0,0,0};
+       uint16_t maxPeak = 255;
+       bool firstpeak = false;
         //test for large clipped waves
         for (i=0; i<loopCnt; i++){
                 if (dest[i] >= peak || dest[i] <= low){
         //test for large clipped waves
         for (i=0; i<loopCnt; i++){
                 if (dest[i] >= peak || dest[i] <= low){
-                       peakcnt++;
+                       if (!firstpeak) continue;
+                       smplCnt++;
                 } else {
                 } else {
-                       if (peakcnt>0 && maxPeak < peakcnt){
-                               maxPeak = peakcnt;
+                       firstpeak=true;
+                       if (smplCnt > 6 ){
+                               if (maxPeak > smplCnt){
+                                       maxPeak = smplCnt;
+                                       //prnt("maxPk: %d",maxPeak);
+                               }
+                               peakcnt++;
+                               //prnt("maxPk: %d, smplCnt: %d, peakcnt: %d",maxPeak,smplCnt,peakcnt);
+                               smplCnt=0;
                         }
                         }
-                       peakcnt=0;
                 }
         }
                 }
         }
+       bool errBitHigh = 0;
+       bool bitHigh = 0;
+       uint8_t ignoreCnt = 0;
+       uint8_t ignoreWindow = 4;
+       bool lastPeakHigh = 0;
+       int lastBit = 0; 
         peakcnt=0;
         //test each valid clock from smallest to greatest to see which lines up
         for(clkCnt=0; clkCnt < 8; ++clkCnt){
         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;
-
+               //ignore clocks smaller than smallest peak
+               if (clk[clkCnt] < maxPeak - (clk[clkCnt]/4)) continue;
                 //try lining up the peaks by moving starting point (try first 256)
                 //try lining up the peaks by moving starting point (try first 256)
-               for (ii=0; ii< loopCnt; ++ii){
+               for (ii=20; ii < loopCnt; ++ii){
                         if ((dest[ii] >= peak) || (dest[ii] <= low)){
                                 peakcnt=0;
                         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){
+                               bitHigh = false;
+                               ignoreCnt = 0;
+                               lastBit = ii-clk[clkCnt]; 
+                               //loop through to see if this start location works
+                               for (i = ii; i < size-20; ++i) {
+                                       //if we are at a clock bit
+                                       if ((i >= lastBit + clk[clkCnt] - tol) && (i <= lastBit + clk[clkCnt] + tol)) {
+                                               //test high/low
+                                               if (dest[i] >= peak || dest[i] <= low) {
+                                                       //if same peak don't count it
+                                                       if ((dest[i] >= peak && !lastPeakHigh) || (dest[i] <= low && lastPeakHigh)) {
                                                 peakcnt++;
                                                 peakcnt++;
+                                                       }
+                                                       lastPeakHigh = (dest[i] >= peak);
+                                                       bitHigh = true;
+                                                       errBitHigh = false;
+                                                       ignoreCnt = ignoreWindow;
+                                                       lastBit += clk[clkCnt];
+                                               } else if (i == lastBit + clk[clkCnt] + tol) {
+                                                       lastBit += clk[clkCnt];
+                                               }
+                                       //else if not a clock bit and no peaks
+                                       } else if (dest[i] < peak && dest[i] > low){
+                                               if (ignoreCnt==0){
+                                                       bitHigh=false;
+                                                       if (errBitHigh==true) peakcnt--;
+                                                       errBitHigh=false;
+                                               } else {
+                                                       ignoreCnt--;
+                                               }
+                                               // else if not a clock bit but we have a peak
+                                       } else if ((dest[i]>=peak || dest[i]<=low) && (!bitHigh)) {
+                                               //error bar found no clock...
+                                               errBitHigh=true;
                                         }
                                 }
                                 if(peakcnt>peaksdet[clkCnt]) {
                                         }
                                 }
                                 if(peakcnt>peaksdet[clkCnt]) {
@@ -1099,47 +1274,48 @@ int DetectNRZClock(uint8_t dest[], size_t size, int clock)
         int iii=7;
         uint8_t best=0;
         for (iii=7; iii > 0; iii--){
         int iii=7;
         uint8_t best=0;
         for (iii=7; iii > 0; iii--){
-               if (peaksdet[iii] > peaksdet[best]){
+               if ((peaksdet[iii] >= (peaksdet[best]-1)) && (peaksdet[iii] <= peaksdet[best]+1) && lowestTransition) {
+                       if (clk[iii] > (lowestTransition - (clk[iii]/8)) && clk[iii] < (lowestTransition + (clk[iii]/8))) {
+                       best = iii;
+               }
+               } else if (peaksdet[iii] > peaksdet[best]){
                         best = iii;
                 }
                         best = iii;
                 }
-               //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]);
+               if (g_debugMode==2) prnt("DEBUG NRZ: Clk: %d, peaks: %d, maxPeak: %d, bestClk: %d, lowestTrs: %d",clk[iii],peaksdet[iii],maxPeak, clk[best], lowestTransition);
         }
         }
+
         return clk[best];
  }
  
  // by marshmellow
  // convert psk1 demod to psk2 demod
  // only transition waves are 1s
         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;
+void psk1TOpsk2(uint8_t *bits, size_t size) {
+       uint8_t lastBit = bits[0];
+       for (size_t i = 1; i < size; i++){
+               //ignore errors         
+               if (bits[i] == 7) continue;
+                       
+               if (lastBit != bits[i]){
+                       lastBit = bits[i];
+                       bits[i] = 1;
                 } else {
                 } else {
-                       BitStream[i]=0;
+                       bits[i] = 0;
                 }
         }
                 }
         }
-       return;
  }
  
  // by marshmellow
  // convert psk2 demod to psk1 demod
  // from only transition waves are 1s to phase shifts change bit
  }
  
  // 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;
+void psk2TOpsk1(uint8_t *bits, size_t size) {
+       uint8_t phase = 0;
+       for (size_t i = 0; i < size; i++){
+               if (bits[i] == 1){
+                       phase ^= 1;
                 }
                 }
-               BitStream[i]=phase;
+               bits[i] = phase;
         }
         }
-       return;
  }
  
  // redesigned by marshmellow adjusted from existing decode functions
  }
  
  // redesigned by marshmellow adjusted from existing decode functions
@@ -1147,182 +1323,53 @@ void psk2TOpsk1(uint8_t *BitStream, size_t size)
  int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
  {
         //26 bit 40134 format  (don't know other formats)
  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;
+       uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
+       uint8_t preamble_i[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
+       size_t startidx = 0; 
+       if (!preambleSearch(bitStream, preamble, sizeof(preamble), size, &startidx)){
+               // if didn't find preamble try again inverting
+               if (!preambleSearch(bitStream, preamble_i, sizeof(preamble_i), size, &startidx)) return -1;
+               *invert ^= 1;
+       } 
+       if (*size != 64 && *size != 224) return -2;
+       if (*invert==1)
+               for (size_t i = startidx; i < *size; i++)
+                       bitStream[i] ^= 1;
  
  
-       // Dumping UID
-       i = start;
-       for (ii = 0; ii < bitCnt; ii++) {
-               bitStream[ii] = bitStream[i++];
-       }
-       *size=bitCnt;
-       return 1;
+       return (int) startidx;
  }
  
  }
  
-// by marshmellow - demodulate NRZ wave (both similar enough)
+// by marshmellow - demodulate NRZ wave - requires a read with strong signal
  // peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
  // 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)
-{
+int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert){
         if (justNoise(dest, *size)) return -1;
         *clk = DetectNRZClock(dest, *size, *clk);
         if (*clk==0) return -2;
         size_t i, gLen = 4096;
         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;
+       if (gLen>*size) gLen = *size-20;
         int high, low;
         if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low
         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
-       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 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 (ignoreCnt==0){
-                                               bitHigh=0;
-                                               if (errBitHigh==1) errCnt++;
-                                               errBitHigh=0;
-                                       } else {
-                                               ignoreCnt--;
-                                       }
-                               } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) {
-                                       //error bar found no clock...
-                                       errBitHigh=1;
-                               }
-                               if (((i-iii) / *clk)>=MaxBits) break;
-                       }
-                       //we got more than 64 good bits and not all errors
-                       if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) {
-                               //possible good read
-                               if (!errCnt || peakCnt > bestPeakCnt){
-                                       bestFirstPeakHigh=firstPeakHigh;
-                                       bestErrCnt = errCnt;
-                                       bestPeakCnt = peakCnt;
-                                       bestPeakStart = iii;
-                                       if (!errCnt) break;  //great read - finish
-                               }
-                       }
-               }
+
+       uint8_t bit=0;
+       //convert wave samples to 1's and 0's
+       for(i=20; i < *size-20; i++){
+               if (dest[i] >= high) bit = 1;
+               if (dest[i] <= low)  bit = 0;
+               dest[i] = bit;
         }
         }
-       //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++] = 77;
-                                       errCnt++;
-                               }
-                               errBitHigh=0;
-                       } else {
-                               ignoreCnt--;
-                       }
-               } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) {
-                       //error bar found no clock...
-                       errBitHigh=1;
+       //now demod based on clock (rf/32 = 32 1's for one 1 bit, 32 0's for one 0 bit) 
+       size_t lastBit = 0;
+       size_t numBits = 0;
+       for(i=21; i < *size-20; i++) {
+               //if transition detected or large number of same bits - store the passed bits
+               if (dest[i] != dest[i-1] || (i-lastBit) == (10 * *clk)) {
+                       memset(dest+numBits, dest[i-1] ^ *invert, (i - lastBit + (*clk/4)) / *clk);
+                       numBits += (i - lastBit + (*clk/4)) / *clk;
+                       lastBit = i-1;
                 }
                 }
-               if (bitnum >= MaxBits) break;
         }
         }
-       *size = bitnum;
-       return bestErrCnt;
+       *size = numBits;
+       return 0;
  }
  
  //by marshmellow
  }
  
  //by marshmellow
@@ -1340,18 +1387,18 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
         size_t i;
         if (size == 0) return 0;
  
         size_t i;
         if (size == 0) return 0;
  
-       uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2);
+       uint8_t fcTol = ((fcHigh*100 - fcLow*100)/2 + 50)/100; //(uint8_t)(0.5+(float)(fcHigh-fcLow)/2);
         rfLensFnd=0;
         fcCounter=0;
         rfCounter=0;
         firstBitFnd=0;
         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++)
+       //prnt("DEBUG: fcTol: %d",fcTol);
+       // prime i to first peak / up transition
+       for (i = 160; i < size-20; i++)
                 if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1])
                         break;
  
                 if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1])
                         break;
  
-       for (; i < size-1; i++){
+       for (; i < size-20; i++){
                 fcCounter++;
                 rfCounter++;
  
                 fcCounter++;
                 rfCounter++;
  
@@ -1359,7 +1406,10 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
                         continue;               
                 // else new peak 
                 // if we got less than the small fc + tolerance then set it to the small fc
                         continue;               
                 // else new peak 
                 // if we got less than the small fc + tolerance then set it to the small fc
-               if (fcCounter < fcLow+fcTol) 
+               // if it is inbetween set it to the last counter
+               if (fcCounter < fcHigh && fcCounter > fcLow)
+                       fcCounter = lastFCcnt;
+               else if (fcCounter < fcLow+fcTol) 
                         fcCounter = fcLow;
                 else //set it to the large fc
                         fcCounter = fcHigh;
                         fcCounter = fcLow;
                 else //set it to the large fc
                         fcCounter = fcHigh;
@@ -1369,14 +1419,14 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
                         //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++){
                         //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){
+                                       if (rfLens[ii] >= (rfCounter-4) && rfLens[ii] <= (rfCounter+4)){
                                                 rfCnts[ii]++;
                                                 rfCounter = 0;
                                                 break;
                                         }
                                 }
                                 if (rfCounter > 0 && rfLensFnd < 15){
                                                 rfCnts[ii]++;
                                                 rfCounter = 0;
                                                 break;
                                         }
                                 }
                                 if (rfCounter > 0 && rfLensFnd < 15){
-                                       //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
+                                       //prnt("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
                                         rfCnts[rfLensFnd]++;
                                         rfLens[rfLensFnd++] = rfCounter;
                                 }
                                         rfCnts[rfLensFnd]++;
                                         rfLens[rfLensFnd++] = rfCounter;
                                 }
@@ -1391,7 +1441,6 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
         uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15;
  
         for (i=0; i<15; i++){
         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;
                 //get highest 2 RF values  (might need to get more values to compare or compare all?)
                 if (rfCnts[i]>rfCnts[rfHighest]){
                         rfHighest3=rfHighest2;
@@ -1403,27 +1452,30 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
                 } else if(rfCnts[i]>rfCnts[rfHighest3]){
                         rfHighest3=i;
                 }
                 } else if(rfCnts[i]>rfCnts[rfHighest3]){
                         rfHighest3=i;
                 }
+               if (g_debugMode==2) prnt("DEBUG FSK: RF %d, cnts %d",rfLens[i], rfCnts[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; 
         
         }  
         // 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]);
+       if (g_debugMode==2) prnt("DEBUG FSK: most counted rf values: 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
  
         // loop to find the highest clock that has a remainder less than the tolerance
         //   compare samples counted divided by
+       // test 128 down to 32 (shouldn't be possible to have fc/10 & fc/8 and rf/16 or less)
         int ii=7;
         int ii=7;
-       for (; ii>=0; ii--){
+       for (; ii>=2; 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){
                 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){
+                                       if (g_debugMode==2) prnt("DEBUG FSK: clk %d divides into the 3 most rf values within tolerance",clk[ii]);
                                         break;
                                 }
                         }
                 }
         }
  
                                         break;
                                 }
                         }
                 }
         }
  
-       if (ii<0) return 0; // oops we went too far
+       if (ii<2) return 0; // oops we went too far
  
         return clk[ii];
  }
  
         return clk[ii];
  }
@@ -1434,20 +1486,20 @@ uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fc
  //mainly used for FSK field clock detection
  uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
  {
  //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 fcLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+       uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
         uint8_t fcLensFnd = 0;
         uint8_t fcLensFnd = 0;
-       uint8_t lastFCcnt=0;
+       uint8_t lastFCcnt = 0;
         uint8_t fcCounter = 0;
         size_t i;
         uint8_t fcCounter = 0;
         size_t i;
-       if (size == 0) return 0;
+       if (size < 180) return 0;
  
         // prime i to first up transition
  
         // prime i to first up transition
-       for (i = 1; i < size-1; i++)
+       for (i = 160; i < size-20; i++)
                 if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1])
                         break;
  
                 if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1])
                         break;
  
-       for (; i < size-1; i++){
+       for (; i < size-20; i++){
                 if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){
                         // new up transition
                         fcCounter++;
                 if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){
                         // new up transition
                         fcCounter++;
@@ -1460,14 +1512,14 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
                         lastFCcnt = fcCounter;
                         }
                         // find which fcLens to save it to:
                         lastFCcnt = fcCounter;
                         }
                         // find which fcLens to save it to:
-                       for (int ii=0; ii<10; ii++){
+                       for (int ii=0; ii<15; ii++){
                                 if (fcLens[ii]==fcCounter){
                                         fcCnts[ii]++;
                                         fcCounter=0;
                                         break;
                                 }
                         }
                                 if (fcLens[ii]==fcCounter){
                                         fcCnts[ii]++;
                                         fcCounter=0;
                                         break;
                                 }
                         }
-                       if (fcCounter>0 && fcLensFnd<10){
+                       if (fcCounter>0 && fcLensFnd<15){
                                 //add new fc length 
                                 fcCnts[fcLensFnd]++;
                                 fcLens[fcLensFnd++]=fcCounter;
                                 //add new fc length 
                                 fcCnts[fcLensFnd]++;
                                 fcLens[fcLensFnd++]=fcCounter;
@@ -1479,11 +1531,10 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
                 }
         }
         
                 }
         }
         
-       uint8_t best1=9, best2=9, best3=9;
+       uint8_t best1=14, best2=14, best3=14;
         uint16_t maxCnt1=0;
         // go through fclens and find which ones are bigest 2  
         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);    
+       for (i=0; i<15; i++){
                 // get the 3 best FC values
                 if (fcCnts[i]>maxCnt1) {
                         best3=best2;
                 // get the 3 best FC values
                 if (fcCnts[i]>maxCnt1) {
                         best3=best2;
@@ -1496,7 +1547,9 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
                 } else if(fcCnts[i]>fcCnts[best3]){
                         best3=i;
                 }
                 } else if(fcCnts[i]>fcCnts[best3]){
                         best3=i;
                 }
+               if (g_debugMode==2) prnt("DEBUG countfc: FC %u, Cnt %u, best fc: %u, best2 fc: %u",fcLens[i],fcCnts[i],fcLens[best1],fcLens[best2]);
         }
         }
+       if (fcLens[best1]==0) return 0;
         uint8_t fcH=0, fcL=0;
         if (fcLens[best1]>fcLens[best2]){
                 fcH=fcLens[best1];
         uint8_t fcH=0, fcL=0;
         if (fcLens[best1]>fcLens[best2]){
                 fcH=fcLens[best1];
@@ -1505,11 +1558,13 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
                 fcH=fcLens[best2];
                 fcL=fcLens[best1];
         }
                 fcH=fcLens[best2];
                 fcL=fcLens[best1];
         }
-
+       if ((size-180)/fcH/3 > fcCnts[best1]+fcCnts[best2]) {
+               if (g_debugMode==2) prnt("DEBUG countfc: fc is too large: %u > %u. Not psk or fsk",(size-180)/fcH/3,fcCnts[best1]+fcCnts[best2]);
+               return 0; //lots of waves not psk or fsk
+       }
         // TODO: take top 3 answers and compare to known Field clocks to get top 2
  
         uint16_t fcs = (((uint16_t)fcH)<<8) | fcL;
         // 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];
  }
         if (fskAdj) return fcs; 
         return fcLens[best1];
  }
@@ -1522,28 +1577,39 @@ 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<loopCnt) loopCnt = *size;
  
         uint16_t loopCnt = 4096;  //don't need to loop through entire array...
         if (*size<loopCnt) loopCnt = *size;
  
+       size_t numBits=0;
         uint8_t curPhase = *invert;
         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);
+       size_t i=0, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
+       uint16_t fc=0, fullWaveLen=0, tol=1;
+       uint16_t errCnt=0, waveLenCnt=0, errCnt2=0;
+       fc = countFC(dest, *size, 1);
+       uint8_t fc2 = fc >> 8;
+       if (fc2 == 10) return -1; //fsk found - quit
+       fc = fc & 0xFF;
         if (fc!=2 && fc!=4 && fc!=8) return -1;
         if (fc!=2 && fc!=4 && fc!=8) return -1;
-       //PrintAndLog("DEBUG: FC: %d",fc);
+       //prnt("DEBUG: FC: %d",fc);
         *clock = DetectPSKClock(dest, *size, *clock);
         if (*clock == 0) return -1;
         *clock = DetectPSKClock(dest, *size, *clock);
         if (*clock == 0) return -1;
-       int avgWaveVal=0, lastAvgWaveVal=0;
+
+       //find start of modulating data in trace 
+       uint8_t threshold_value = 123; //-5
+       i = findModStart(dest, *size, threshold_value, fc);
+
         //find first phase shift
         //find first phase shift
-       for (i=0; i<loopCnt; i++){
+       int avgWaveVal=0, lastAvgWaveVal=0;
+       waveStart = i;
+       for (; i<loopCnt; i++){
+               // find peak 
                 if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
                         waveEnd = i+1;
                 if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
                         waveEnd = i+1;
-                       //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+                       if (g_debugMode == 2) prnt("DEBUG PSK: waveEnd: %u, waveStart: %u",waveEnd, waveStart);
                         waveLenCnt = waveEnd-waveStart;
                         waveLenCnt = waveEnd-waveStart;
-                       if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave 
+                       if (waveLenCnt > fc && waveStart > fc && !(waveLenCnt > fc+3)){ //not first peak and is a large wave but not out of whack
                                 lastAvgWaveVal = avgWaveVal/(waveLenCnt);
                                 firstFullWave = waveStart;
                                 fullWaveLen=waveLenCnt;
                                 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
+                               //if average wave value is > graph 0 then it is an up wave or a 1 (could cause inverting)
+                               if (lastAvgWaveVal > threshold_value) curPhase ^= 1;
                                 break;
                         } 
                         waveStart = i+1;
                                 break;
                         } 
                         waveStart = i+1;
@@ -1551,14 +1617,21 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
                 }
                 avgWaveVal += dest[i+2];
         }
                 }
                 avgWaveVal += dest[i+2];
         }
-       //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);  
-       lastClkBit = firstFullWave; //set start of wave as clock align
-       //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit);
-       waveStart = 0;
-       size_t numBits=0;
-       //set skipped bits
-       memset(dest, curPhase^1, firstFullWave / *clock);
+       if (firstFullWave == 0) {
+               // no phase shift detected - could be all 1's or 0's - doesn't matter where we start
+               // so skip a little to ensure we are past any Start Signal
+               firstFullWave = 160;
+               memset(dest, curPhase, firstFullWave / *clock);
+       } else {
+               memset(dest, curPhase^1, firstFullWave / *clock);
+       }
+       //advance bits
         numBits += (firstFullWave / *clock);
         numBits += (firstFullWave / *clock);
+       //set start of wave as clock align
+       lastClkBit = firstFullWave;
+       if (g_debugMode==2) prnt("DEBUG PSK: firstFullWave: %u, waveLen: %u",firstFullWave,fullWaveLen);  
+       if (g_debugMode==2) prnt("DEBUG PSK: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc);
+       waveStart = 0;
         dest[numBits++] = curPhase; //set first read bit
         for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
                 //top edge of wave = start of new wave 
         dest[numBits++] = curPhase; //set first read bit
         for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
                 //top edge of wave = start of new wave 
@@ -1572,9 +1645,9 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
                                 waveLenCnt = waveEnd-waveStart;
                                 lastAvgWaveVal = avgWaveVal/waveLenCnt;
                                 if (waveLenCnt > fc){  
                                 waveLenCnt = waveEnd-waveStart;
                                 lastAvgWaveVal = avgWaveVal/waveLenCnt;
                                 if (waveLenCnt > fc){  
-                                       //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
+                                       //prnt("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
                                         //this wave is a phase shift
                                         //this wave is a phase shift
-                                       //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
+                                       //prnt("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;
                                         if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit
                                                 curPhase ^= 1;
                                                 dest[numBits++] = curPhase;
@@ -1583,11 +1656,14 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
                                                 //noise after a phase shift - ignore
                                         } else { //phase shift before supposed to based on clock
                                                 errCnt++;
                                                 //noise after a phase shift - ignore
                                         } else { //phase shift before supposed to based on clock
                                                 errCnt++;
-                                               dest[numBits++] = 77;
+                                               dest[numBits++] = 7;
                                         }
                                 } else if (i+1 > lastClkBit + *clock + tol + fc){
                                         lastClkBit += *clock; //no phase shift but clock bit
                                         dest[numBits++] = curPhase;
                                         }
                                 } else if (i+1 > lastClkBit + *clock + tol + fc){
                                         lastClkBit += *clock; //no phase shift but clock bit
                                         dest[numBits++] = curPhase;
+                               } else if (waveLenCnt < fc - 1) { //wave is smaller than field clock (shouldn't happen often)
+                                       errCnt2++;
+                                       if(errCnt2 > 101) return errCnt2;
                                 }
                                 avgWaveVal = 0;
                                 waveStart = i+1;
                                 }
                                 avgWaveVal = 0;
                                 waveStart = i+1;
@@ -1598,3 +1674,186 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
         *size = numBits;
         return errCnt;
  }
         *size = numBits;
         return errCnt;
  }
+
+//by marshmellow
+//attempt to identify a Sequence Terminator in ASK modulated raw wave
+bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) {
+       size_t bufsize = *size;
+       //need to loop through all samples and identify our clock, look for the ST pattern
+       uint8_t fndClk[] = {8,16,32,40,50,64,128};
+       int clk = 0; 
+       int tol = 0;
+       int i, j, skip, start, end, low, high, minClk, waveStart;
+       bool complete = false;
+       int tmpbuff[bufsize / 32]; //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured
+       int waveLen[bufsize / 32]; //  if clock is larger then we waste memory in array size that is not needed...
+       size_t testsize = (bufsize < 512) ? bufsize : 512;
+       int phaseoff = 0;
+       high = low = 128;
+       memset(tmpbuff, 0, sizeof(tmpbuff));
+       memset(waveLen, 0, sizeof(waveLen));
+
+       
+       if ( getHiLo(buffer, testsize, &high, &low, 80, 80) == -1 ) {
+               if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting");
+               return false; //just noise
+       }
+       i = 0;
+       j = 0;
+       minClk = 255;
+       // get to first full low to prime loop and skip incomplete first pulse
+       while ((buffer[i] < high) && (i < bufsize))
+               ++i;
+       while ((buffer[i] > low) && (i < bufsize))
+               ++i;
+       skip = i;
+
+       // populate tmpbuff buffer with pulse lengths
+       while (i < bufsize) {
+               // measure from low to low
+               while ((buffer[i] > low) && (i < bufsize))
+                       ++i;
+               start= i;
+               while ((buffer[i] < high) && (i < bufsize))
+                       ++i;
+               //first high point for this wave
+               waveStart = i;
+               while ((buffer[i] > low) && (i < bufsize))
+                       ++i;
+               if (j >= (bufsize/32)) {
+                       break;
+               }
+               waveLen[j] = i - waveStart; //first high to first low
+               tmpbuff[j++] = i - start;
+               if (i-start < minClk && i < bufsize) {
+                       minClk = i - start;
+               }
+       }
+       // set clock  - might be able to get this externally and remove this work...
+       if (!clk) {
+               for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
+                       tol = fndClk[clkCnt]/8;
+                       if (minClk >= fndClk[clkCnt]-tol && minClk <= fndClk[clkCnt]+1) { 
+                               clk=fndClk[clkCnt];
+                               break;
+                       }
+               }
+               // clock not found - ERROR
+               if (!clk) {
+                       if (g_debugMode==2) prnt("DEBUG STT: clock not found - quitting");
+                       return false;
+               }
+       } else tol = clk/8;
+
+       *foundclock = clk;
+
+       // look for Sequence Terminator - should be pulses of clk*(1 or 1.5), clk*2, clk*(1.5 or 2)
+       start = -1;
+       for (i = 0; i < j - 4; ++i) {
+               skip += tmpbuff[i];
+               if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) {           //1 to 2 clocks depending on 2 bits prior
+                       if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol && waveLen[i+1] > clk*3/2-tol) {       //2 clocks and wave size is 1 1/2
+                               if (tmpbuff[i+2] >= (clk*3)/2-tol && tmpbuff[i+2] <= clk*2+tol && waveLen[i+2] > clk-tol) { //1 1/2 to 2 clocks and at least one full clock wave
+                                       if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit
+                                               start = i + 3;
+                                               break;
+                                       }
+                               }
+                       }
+               }
+       }
+       // first ST not found - ERROR
+       if (start < 0) {
+               if (g_debugMode==2) prnt("DEBUG STT: first STT not found - quitting");
+               return false;
+       } else {
+               if (g_debugMode==2) prnt("DEBUG STT: first STT found at: %d, j=%d",start, j);
+       }
+       if (waveLen[i+2] > clk*1+tol)
+               phaseoff = 0;
+       else
+               phaseoff = clk/2;
+       
+       // skip over the remainder of ST
+       skip += clk*7/2; //3.5 clocks from tmpbuff[i] = end of st - also aligns for ending point
+
+       // now do it again to find the end
+       end = skip;
+       for (i += 3; i < j - 4; ++i) {
+               end += tmpbuff[i];
+               if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) {           //1 to 2 clocks depending on 2 bits prior
+                       if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol && waveLen[i+1] > clk*3/2-tol) {       //2 clocks and wave size is 1 1/2
+                               if (tmpbuff[i+2] >= (clk*3)/2-tol && tmpbuff[i+2] <= clk*2+tol && waveLen[i+2] > clk-tol) { //1 1/2 to 2 clocks and at least one full clock wave
+                                       if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit
+                                               complete = true;
+                                               break;
+                                       }
+                               }
+                       }
+               }
+       }
+       end -= phaseoff;
+       //didn't find second ST - ERROR
+       if (!complete) {
+               if (g_debugMode==2) prnt("DEBUG STT: second STT not found - quitting");
+               return false;
+       }
+       if (g_debugMode==2) prnt("DEBUG STT: start of data: %d end of data: %d, datalen: %d, clk: %d, bits: %d, phaseoff: %d", skip, end, end-skip, clk, (end-skip)/clk, phaseoff);
+       //now begin to trim out ST so we can use normal demod cmds
+       start = skip;
+       size_t datalen = end - start;
+       // check validity of datalen (should be even clock increments)  - use a tolerance of up to 1/8th a clock
+       if ( clk - (datalen % clk) <= clk/8) {
+               // padd the amount off - could be problematic...  but shouldn't happen often
+               datalen += clk - (datalen % clk);
+       } else if ( (datalen % clk) <= clk/8 ) {
+               // padd the amount off - could be problematic...  but shouldn't happen often
+               datalen -= datalen % clk;
+       } else {
+               if (g_debugMode==2) prnt("DEBUG STT: datalen not divisible by clk: %u %% %d = %d - quitting", datalen, clk, datalen % clk);
+               return false;
+       }
+       // if datalen is less than one t55xx block - ERROR
+       if (datalen/clk < 8*4) {
+               if (g_debugMode==2) prnt("DEBUG STT: datalen is less than 1 full t55xx block - quitting");              
+               return false;
+       }
+       size_t dataloc = start;
+       if (buffer[dataloc-(clk*4)-(clk/8)] <= low && buffer[dataloc] <= low && buffer[dataloc-(clk*4)] >= high) {
+               //we have low drift (and a low just before the ST and a low just after the ST) - compensate by backing up the start 
+               for ( i=0; i <= (clk/8); ++i ) {
+                       if ( buffer[dataloc - (clk*4) - i] <= low ) {
+                               dataloc -= i;
+                               break;
+                       }
+               }
+       }
+       
+       size_t newloc = 0;
+       i=0;
+       if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen);            
+
+       // warning - overwriting buffer given with raw wave data with ST removed...
+       while ( dataloc < bufsize-(clk/2) ) {
+               //compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part)
+               if (buffer[dataloc]<high && buffer[dataloc]>low && buffer[dataloc+3]<high && buffer[dataloc+3]>low) {
+                       for(i=0; i < clk/2-tol; ++i) {
+                               buffer[dataloc+i] = high+5;
+                       }
+               }
+               for (i=0; i<datalen; ++i) {
+                       if (i+newloc < bufsize) {
+                               if (i+newloc < dataloc)
+                                       buffer[i+newloc] = buffer[dataloc];
+
+                               dataloc++;                              
+                       }
+               }
+               newloc += i;
+               //skip next ST  -  we just assume it will be there from now on...
+               if (g_debugMode==2) prnt("DEBUG STT: skipping STT at %d to %d", dataloc, dataloc+(clk*4));
+               dataloc += clk*4;
+       }
+       *size = newloc;
+       return true;
+}