]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - common/lfdemod.c
minor code cleanup
[proxmark3-svn] / common / lfdemod.c
index 1c3aad6fa8e123a766cb117307e1d408f9ba9e3f..25e5255241a63fd0743dedc0cdbbb80bfafef3a6 100644 (file)
@@ -1,5 +1,5 @@
 //-----------------------------------------------------------------------------
-// Copyright (C) 2014 
+// Copyright (C) 2014
 //
 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
 // at your option, any later version. See the LICENSE.txt file for the text of
 // Low frequency commands
 //-----------------------------------------------------------------------------
 
-//#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-//#include <inttypes.h>
-//#include <limits.h>
 #include "lfdemod.h"
-//#include "proxmark3.h"
-//#include "data.h"
-//#include "ui.h"
-//#include "graph.h"
-//#include "cmdparser.h"
-//#include "util.h"
-//#include "cmdmain.h"
-//#include "cmddata.h"
-//uint8_t BinStream[MAX_GRAPH_TRACE_LEN];
-//uint8_t BinStreamLen;
 
 //by marshmellow
 //takes 1s and 0s and searches for EM410x format - output EM ID
-uint64_t Em410xDecode(uint8_t *BitStream,uint32_t BitLen)
+uint64_t Em410xDecode(uint8_t *BitStream, size_t size)
 {
-  //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
-  //  otherwise could be a void with no arguments
-  //set defaults
-  int high=0, low=0;
-  uint64_t lo=0; //hi=0,
-
-  uint32_t i = 0;
-  uint32_t initLoopMax = 65;
-  if (initLoopMax>BitLen) initLoopMax=BitLen;
-
-  for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values
-  {
-    if (BitStream[i] > high)
-      high = BitStream[i];
-    else if (BitStream[i] < low)
-      low = BitStream[i];
-  }
-  if (((high !=1)||(low !=0))){  //allow only 1s and 0s 
-   // PrintAndLog("no data found"); 
-    return 0;
-  }
-  uint8_t parityTest=0;
-   // 111111111 bit pattern represent start of frame
-  uint8_t frame_marker_mask[] = {1,1,1,1,1,1,1,1,1};
-  uint32_t idx = 0;
-  uint32_t ii=0;
-  uint8_t resetCnt = 0;
-  while( (idx + 64) < BitLen) {
+       //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
+       //  otherwise could be a void with no arguments
+       //set defaults
+       int high=0, low=128;
+       uint64_t lo=0;
+
+       uint32_t i = 0;
+       uint32_t initLoopMax = 65;
+       if (initLoopMax>size) initLoopMax=size;
+
+       for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values
+       {
+               if (BitStream[i] > high)
+                       high = BitStream[i];
+               else if (BitStream[i] < low)
+                       low = BitStream[i];
+       }
+       if (((high !=1)||(low !=0))){  //allow only 1s and 0s
+               // PrintAndLog("no data found");
+               return 0;
+       }
+       uint8_t parityTest=0;
+       // 111111111 bit pattern represent start of frame
+       uint8_t frame_marker_mask[] = {1,1,1,1,1,1,1,1,1};
+       uint32_t idx = 0;
+       uint32_t ii=0;
+       uint8_t resetCnt = 0;
+       while( (idx + 64) < size) {
  restart:
-    // search for a start of frame marker
-    if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
-    { // frame marker found
-      idx+=9;//sizeof(frame_marker_mask);
-      for (i=0; i<10;i++){
-        for(ii=0; ii<5; ++ii){
-          parityTest += BitStream[(i*5)+ii+idx];        
-        }
-        if (parityTest== ((parityTest>>1)<<1)){
-          parityTest=0;
-          for (ii=0; ii<4;++ii){
-            //hi = (hi<<1)|(lo>>31);
-            lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]);
-          }
-          //PrintAndLog("DEBUG: EM parity passed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d,lo: %d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1],lo);          
-        }else {//parity failed
-          //PrintAndLog("DEBUG: EM parity failed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1]);
-          parityTest=0;
-          idx-=8;
-          if (resetCnt>5)return 0;
-          resetCnt++;
-          goto restart;//continue;
-        }
-      }
-      //skip last 5 bit parity test for simplicity.
-      return lo;
-    }else{
-      idx++;
-    }
-  }
-  return 0;
+               // search for a start of frame marker
+               if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
+               { // frame marker found
+                       idx+=9;
+                       for (i=0; i<10;i++){
+                               for(ii=0; ii<5; ++ii){
+                                       parityTest += BitStream[(i*5)+ii+idx];
+                               }
+                               if (parityTest== ((parityTest>>1)<<1)){
+                                       parityTest=0;
+                                       for (ii=0; ii<4;++ii){
+                                               lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]);
+                                       }
+                                       //PrintAndLog("DEBUG: EM parity passed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d,lo: %d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1],lo);
+                               }else {//parity failed
+                                       //PrintAndLog("DEBUG: EM parity failed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1]);
+                                       parityTest=0;
+                                       idx-=8;
+                                       if (resetCnt>5)return 0;
+                                       resetCnt++;
+                                       goto restart;//continue;
+                               }
+                       }
+                       //skip last 5 bit parity test for simplicity.
+                       return lo;
+               }else{
+                       idx++;
+               }
+       }
+       return 0;
 }
 
 //by marshmellow
 //takes 2 arguments - clock and invert both as integers
-//attempts to demodulate ask while decoding manchester 
+//attempts to demodulate ask while decoding manchester
 //prints binary found and saves in graphbuffer for further commands
-int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert)
+int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert)
 {
-  uint32_t i;
-  //int invert=0;  //invert default
-  int high = 0, low = 0;
-  *clk=DetectClock2(BinStream,(size_t)*BitLen,*clk); //clock default
-  uint8_t BitStream[252] = {0};
-
-  //sscanf(Cmd, "%i %i", &clk, &invert);    
-  if (*clk<8) *clk =64;
-  if (*clk<32) *clk=32;
-  if (*invert != 0 && *invert != 1) *invert=0;
-  uint32_t initLoopMax = 200;
-  if (initLoopMax>*BitLen) initLoopMax=*BitLen;
-  // Detect high and lows 
-  //PrintAndLog("Using Clock: %d  and invert=%d",clk,invert);
-  for (i = 0; i < initLoopMax; ++i) //200 samples should be enough to find high and low values
-  {
-    if (BinStream[i] > high)
-      high = BinStream[i];
-    else if (BinStream[i] < low)
-      low = BinStream[i];
-  }
-  if ((high < 30) && ((high !=1)||(low !=-1))){  //throw away static - allow 1 and -1 (in case of threshold command first)
-    //PrintAndLog("no data found"); 
-    return -1;
-  }
-  //13% fuzz in case highs and lows aren't clipped [marshmellow]
-  high=(int)(0.75*high);
-  low=(int)(0.75*low);
-
-  //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
-  int lastBit = 0;  //set first clock check
-  uint32_t bitnum = 0;     //output counter
-  uint8_t tol = 0;  //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
-  if (*clk==32)tol=1;    //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely 
-  uint32_t iii = 0;
-  uint32_t gLen = *BitLen;
-  if (gLen > 500) gLen=500;
-  uint8_t errCnt =0;
-  uint32_t bestStart = *BitLen;
-  uint32_t bestErrCnt = (*BitLen/1000);
-  //PrintAndLog("DEBUG - lastbit - %d",lastBit);
-  //loop to find first wave that works
-  for (iii=0; iii < gLen; ++iii){
-    if ((BinStream[iii]>=high)||(BinStream[iii]<=low)){
-      lastBit=iii-*clk;    
-      bitnum=0;
-      //loop through to see if this start location works
-      for (i = iii; i < *BitLen; ++i) {   
-        if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){
-          lastBit+=*clk;
-          BitStream[bitnum] =  *invert;
-          bitnum++;
-        } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
-          //low found and we are expecting a bar
-          lastBit+=*clk;
-          BitStream[bitnum] = 1-*invert; 
-          bitnum++;
-        } else {
-          //mid value found or no bar supposed to be here
-          if ((i-lastBit)>(*clk+tol)){
-            //should have hit a high or low based on clock!!
-
-             
-            //debug
-            //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-            if (bitnum > 0){
-              BitStream[bitnum]=77;
-              bitnum++;
-            }
-            
-
-            errCnt++;
-            lastBit+=*clk;//skip over until hit too many errors
-            if (errCnt>((*BitLen/1000))){  //allow 1 error for every 1000 samples else start over
-              errCnt=0;
-              bitnum=0;//start over
-              break;
-            }
-          }
-        }
-        if (bitnum >250) break;
-      }
-      //we got more than 64 good bits and not all errors
-      if ((bitnum > (64+errCnt)) && (errCnt<(*BitLen/1000))) {
-        //possible good read
-        if (errCnt==0) break;  //great read - finish
-        if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish 
-        if (errCnt<bestErrCnt){  //set this as new best run
-          bestErrCnt=errCnt;
-          bestStart = iii;
-        }
-      }
-    }
-    if (iii>=gLen){ //exhausted test
-      //if there was a ok test go back to that one and re-run the best run (then dump after that run)
-      if (bestErrCnt < (*BitLen/1000)) iii=bestStart;
-    }
-  }
-  if (bitnum>16){
-    
-   // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum);
-    //move BitStream back to GraphBuffer
-    //ClearGraph(0);
-    for (i=0; i < bitnum; ++i){
-      BinStream[i]=BitStream[i];
-    }
-    *BitLen=bitnum;
-    //RepaintGraphWindow();
-    //output
-    //if (errCnt>0){
-     // PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt);
-    //}
-   // PrintAndLog("ASK decoded bitstream:");
-    // Now output the bitstream to the scrollback by line of 16 bits
-   // printBitStream2(BitStream,bitnum);
-   // Em410xDecode(Cmd);
-  }  
-  return errCnt;
+       int i;
+       int high = 0, low = 128;
+       *clk=DetectASKClock(BinStream, *size, *clk); //clock default
+
+       if (*clk<8) *clk =64;
+       if (*clk<32) *clk=32;
+       if (*invert != 0 && *invert != 1) *invert=0;
+       uint32_t initLoopMax = 200;
+       if (initLoopMax > *size) initLoopMax=*size;
+       // Detect high and lows
+       for (i = 0; i < initLoopMax; ++i) //200 samples should be enough to find high and low values
+       {
+               if (BinStream[i] > high)
+                       high = BinStream[i];
+               else if (BinStream[i] < low)
+                       low = BinStream[i];
+       }
+       if ((high < 158) ){  //throw away static
+               //PrintAndLog("no data found");
+               return -2;
+       }
+       //25% fuzz in case highs and lows aren't clipped [marshmellow]
+       high=(int)(((high-128)*.75)+128);
+       low= (int)(((low-128)*.75)+128);
+
+       //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
+       int lastBit = 0;  //set first clock check
+       uint32_t bitnum = 0;     //output counter
+       int tol = 0;  //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
+       if (*clk==32)tol=1;    //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
+       int iii = 0;
+       uint32_t gLen = *size;
+       if (gLen > 3000) gLen=3000;
+       uint8_t errCnt =0;
+       uint32_t bestStart = *size;
+       uint32_t bestErrCnt = (*size/1000);
+       uint32_t maxErr = (*size/1000);
+       //PrintAndLog("DEBUG - lastbit - %d",lastBit);
+       //loop to find first wave that works
+       for (iii=0; iii < gLen; ++iii){
+               if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){
+                       lastBit=iii-*clk;
+                       errCnt=0;
+                       //loop through to see if this start location works
+                       for (i = iii; i < *size; ++i) {
+                               if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
+                                       lastBit+=*clk;
+                               } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
+                                       //low found and we are expecting a bar
+                                       lastBit+=*clk;
+                               } else {
+                                       //mid value found or no bar supposed to be here
+                                       if ((i-lastBit)>(*clk+tol)){
+                                               //should have hit a high or low based on clock!!
+
+                                               //debug
+                                               //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
+
+                                               errCnt++;
+                                               lastBit+=*clk;//skip over until hit too many errors
+                                               if (errCnt>(maxErr)) break;  //allow 1 error for every 1000 samples else start over
+                                       }
+                               }
+                               if ((i-iii) >(400 * *clk)) break; //got plenty of bits
+                       }
+                       //we got more than 64 good bits and not all errors
+                       if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<maxErr)) {
+                               //possible good read
+                               if (errCnt==0){
+                                       bestStart=iii;
+                                       bestErrCnt=errCnt;
+                                       break;  //great read - finish
+                               }
+                               if (errCnt<bestErrCnt){  //set this as new best run
+                                       bestErrCnt=errCnt;
+                                       bestStart = iii;
+                               }
+                       }
+               }
+       }
+       if (bestErrCnt<maxErr){
+               //best run is good enough set to best run and set overwrite BinStream
+               iii=bestStart;
+               lastBit = bestStart - *clk;
+               bitnum=0;
+               for (i = iii; i < *size; ++i) {
+                       if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
+                               lastBit += *clk;
+                               BinStream[bitnum] = *invert;
+                               bitnum++;
+                       } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
+                               //low found and we are expecting a bar
+                               lastBit+=*clk;
+                               BinStream[bitnum] = 1-*invert;
+                               bitnum++;
+                       } else {
+                               //mid value found or no bar supposed to be here
+                               if ((i-lastBit)>(*clk+tol)){
+                                       //should have hit a high or low based on clock!!
+
+                                       //debug
+                                       //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
+                                       if (bitnum > 0){
+                                               BinStream[bitnum]=77;
+                                               bitnum++;
+                                       }
+
+                                       lastBit+=*clk;//skip over error
+                               }
+                       }
+                       if (bitnum >=400) break;
+               }
+               *size=bitnum;
+       } else{
+               *invert=bestStart;
+               *clk=iii;
+               return -1;
+       }
+       return bestErrCnt;
 }
 
 //by marshmellow
 //take 10 and 01 and manchester decode
 //run through 2 times and take least errCnt
-int manrawdemod(uint8_t * BitStream, int *bitLen)
+int manrawdecode(uint8_t * BitStream, size_t *size)
 {
-  uint8_t BitStream2[252]={0};
-  int bitnum=0;
-  int errCnt =0;
-  int i=1;
-  int bestErr = 1000;
-  int bestRun = 0;
-  int finish = 0;
-  int ii=1;
-  for (ii=1;ii<3;++ii){
-       i=1;
-               for (i=i+ii;i<*bitLen-2;i+=2){
-                 if(BitStream[i]==1 && (BitStream[i+1]==0)){
-                   BitStream2[bitnum++]=0;
-                 } else if((BitStream[i]==0)&& BitStream[i+1]==1){
-                   BitStream2[bitnum++]=1;
-           } else {
-                   BitStream2[bitnum++]=77;
-                     errCnt++;
-           }
-           if(bitnum>250) break;
+       int bitnum=0;
+       int errCnt =0;
+       int i=1;
+       int bestErr = 1000;
+       int bestRun = 0;
+       int ii=1;
+       for (ii=1;ii<3;++ii){
+               i=1;
+               for (i=i+ii;i<*size-2;i+=2){
+                       if(BitStream[i]==1 && (BitStream[i+1]==0)){
+                       } else if((BitStream[i]==0)&& BitStream[i+1]==1){
+                       } else {
+                               errCnt++;
+                       }
+                       if(bitnum>300) break;
                }
                if (bestErr>errCnt){
-                 bestErr=errCnt;
-                 bestRun=ii;
-               }       
-               if (ii>1 || finish==1) {
-                       if (bestRun==ii) {
-                               break;
-                       }  else{
-                         ii=bestRun-1;
-                   finish=1;
-                 }     
+                       bestErr=errCnt;
+                       bestRun=ii;
                }
                errCnt=0;
-               bitnum=0;
-  }
-  errCnt=bestErr;
-  if (errCnt<20){
-    for (i=0; i<bitnum;++i){
-      BitStream[i]=BitStream2[i];
-    }  
-    *bitLen=bitnum;
-  }
-  return errCnt;
+       }
+       errCnt=bestErr;
+       if (errCnt<20){
+               ii=bestRun;
+               i=1;
+               for (i=i+ii;i < *size-2;i+=2){
+                       if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
+                               BitStream[bitnum++]=0;
+                       } else if((BitStream[i] == 0) && BitStream[i+1] == 1){
+                               BitStream[bitnum++]=1;
+                       } else {
+                               BitStream[bitnum++]=77;
+                               //errCnt++;
+                       }
+                       if(bitnum>300) break;
+               }
+               *size=bitnum;
+       }
+       return errCnt;
+}
+
+
+//by marshmellow
+//take 01 or 10 = 0 and 11 or 00 = 1
+int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset)
+{
+       uint8_t bitnum=0;
+       uint32_t errCnt =0;
+       uint32_t i=1;
+       i=offset;
+       for (;i<*size-2;i+=2){
+               if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){
+                       BitStream[bitnum++]=1;
+               } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
+                       BitStream[bitnum++]=0;
+               } else {
+                       BitStream[bitnum++]=77;
+                       errCnt++;
+               }
+               if(bitnum>250) break;
+       }
+       *size=bitnum;
+       return errCnt;
 }
 
 //by marshmellow
 //takes 2 arguments - clock and invert both as integers
 //attempts to demodulate ask only
 //prints binary found and saves in graphbuffer for further commands
-int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
+int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert)
 {
-  uint32_t i;
- // int invert=0;  //invert default
-  int high = 0, low = 0;
-  *clk=DetectClock2(BinStream,*bitLen,*clk); //clock default
-  uint8_t BitStream[502] = {0};
-
-  if (*clk<8) *clk =64;
-  if (*clk<32) *clk=32;
-  if (*invert != 0 && *invert != 1) *invert =0;
-  uint32_t initLoopMax = 200;
-  if (initLoopMax>*bitLen) initLoopMax=*bitLen;
-  // Detect high and lows 
-  for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values
-  {
-    if (BinStream[i] > high)
-      high = BinStream[i];
-    else if (BinStream[i] < low)
-      low = BinStream[i];
-  }
-  if ((high < 30) && ((high !=1)||(low !=-1))){  //throw away static - allow 1 and -1 (in case of threshold command first)
- //   PrintAndLog("no data found"); 
-    return -1;
-  }
-  //25% fuzz in case highs and lows aren't clipped [marshmellow]
-  high=(int)(0.75*high);
-  low=(int)(0.75*low);
-
-  //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
-  int lastBit = 0;  //set first clock check
-  uint32_t bitnum = 0;     //output counter
-  uint8_t tol = 0;  //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
-  if (*clk==32)tol=1;    //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely 
-  uint32_t iii = 0;
-  uint32_t gLen = *bitLen;
-  if (gLen > 500) gLen=500;
-  uint8_t errCnt =0;
-  uint32_t bestStart = *bitLen;
-  uint32_t bestErrCnt = (*bitLen/1000);
-  uint8_t midBit=0;
-  //PrintAndLog("DEBUG - lastbit - %d",lastBit);
-  //loop to find first wave that works
-  for (iii=0; iii < gLen; ++iii){
-    if ((BinStream[iii]>=high)||(BinStream[iii]<=low)){
-      lastBit=iii-*clk;    
-      //loop through to see if this start location works
-      for (i = iii; i < *bitLen; ++i) {  
-        if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){
-          lastBit+=*clk;
-          BitStream[bitnum] =  *invert;
-          bitnum++;
-          midBit=0;
-        } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
-          //low found and we are expecting a bar
-          lastBit+=*clk;
-          BitStream[bitnum] = 1-*invert; 
-          bitnum++;
-          midBit=0;
-        } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
-          //mid bar?
-          midBit=1;
-          BitStream[bitnum]= 1-*invert;
-          bitnum++;
-        } else if ((BinStream[i]>=high)&&(midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
-          //mid bar?
-          midBit=1;
-          BitStream[bitnum]= *invert;
-          bitnum++;
-        } else if ((i-lastBit)>((*clk/2)+tol)&&(midBit==0)){
-          //no mid bar found
-          midBit=1;
-          BitStream[bitnum]= BitStream[bitnum-1];
-          bitnum++;
-        } else {
-          //mid value found or no bar supposed to be here
-
-          if ((i-lastBit)>(*clk+tol)){
-            //should have hit a high or low based on clock!!
-            //debug
-            //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-            if (bitnum > 0){
-              BitStream[bitnum]=77;
-              bitnum++;
-            }
-            
-
-            errCnt++;
-            lastBit+=*clk;//skip over until hit too many errors
-            if (errCnt>((*bitLen/1000))){  //allow 1 error for every 1000 samples else start over
-              errCnt=0;
-              bitnum=0;//start over
-              break;
-            }
-          }          
-        }
-        if (bitnum>500) break;
-      }
-      //we got more than 64 good bits and not all errors
-      if ((bitnum > (64+errCnt)) && (errCnt<(*bitLen/1000))) {
-        //possible good read
-        if (errCnt==0) break;  //great read - finish
-        if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish 
-        if (errCnt<bestErrCnt){  //set this as new best run
-          bestErrCnt=errCnt;
-          bestStart = iii;
-        }
-      }
-    }
-    if (iii>=gLen){ //exhausted test
-      //if there was a ok test go back to that one and re-run the best run (then dump after that run)
-      if (bestErrCnt < (*bitLen/1000)) iii=bestStart;
-    }
-  }
-  if (bitnum>16){
-    
-   // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum);
-    //move BitStream back to BinStream
-   // ClearGraph(0);
-    for (i=0; i < bitnum; ++i){
-      BinStream[i]=BitStream[i];
-    }
-    *bitLen=bitnum;
-   // RepaintGraphWindow();
-    //output
-   // if (errCnt>0){
-   //   PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt);
-   // }
-   // PrintAndLog("ASK decoded bitstream:");
-    // Now output the bitstream to the scrollback by line of 16 bits
-   // printBitStream2(BitStream,bitnum);
-    //int errCnt=0;
-    //errCnt=manrawdemod(BitStream,bitnum);
-
- //   Em410xDecode(Cmd);
-  } else return -1;
-  return errCnt;
+       uint32_t i;
+       // int invert=0;  //invert default
+       int high = 0, low = 128;
+       *clk=DetectASKClock(BinStream, *size, *clk); //clock default
+       uint8_t BitStream[502] = {0};
+
+       if (*clk<8) *clk =64;
+       if (*clk<32) *clk=32;
+       if (*invert != 0 && *invert != 1) *invert =0;
+       uint32_t initLoopMax = 200;
+       if (initLoopMax > *size) initLoopMax=*size;
+       // Detect high and lows
+       for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values
+       {
+               if (BinStream[i] > high)
+                       high = BinStream[i];
+               else if (BinStream[i] < low)
+                       low = BinStream[i];
+       }
+       if ((high < 158)){  //throw away static
+               //   PrintAndLog("no data found");
+               return -2;
+       }
+       //25% fuzz in case highs and lows aren't clipped [marshmellow]
+       high=(int)(((high-128)*.75)+128);
+       low= (int)(((low-128)*.75)+128);
+
+       //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
+       int lastBit = 0;  //set first clock check
+       uint32_t bitnum = 0;     //output counter
+       uint8_t tol = 0;  //clock tolerance adjust - waves will be accepted as within the clock
+                         //  if they fall + or - this value + clock from last valid wave
+       if (*clk == 32) tol=1;    //clock tolerance may not be needed anymore currently set to
+                                 //  + or - 1 but could be increased for poor waves or removed entirely
+       uint32_t iii = 0;
+       uint32_t gLen = *size;
+       if (gLen > 500) gLen=500;
+       uint8_t errCnt =0;
+       uint32_t bestStart = *size;
+       uint32_t bestErrCnt = (*size/1000);
+       uint8_t midBit=0;
+       //PrintAndLog("DEBUG - lastbit - %d",lastBit);
+       //loop to find first wave that works
+       for (iii=0; iii < gLen; ++iii){
+               if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){
+                       lastBit=iii-*clk;
+                       //loop through to see if this start location works
+                       for (i = iii; i < *size; ++i) {
+                               if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){
+                                       lastBit+=*clk;
+                                       BitStream[bitnum] = *invert;
+                                       bitnum++;
+                                       midBit=0;
+                               } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
+                                       //low found and we are expecting a bar
+                                       lastBit+=*clk;
+                                       BitStream[bitnum] = 1- *invert;
+                                       bitnum++;
+                                       midBit=0;
+                               } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
+                                       //mid bar?
+                                       midBit=1;
+                                       BitStream[bitnum]= 1- *invert;
+                                       bitnum++;
+                               } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
+                                       //mid bar?
+                                       midBit=1;
+                                       BitStream[bitnum]= *invert;
+                                       bitnum++;
+                               } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){
+                                       //no mid bar found
+                                       midBit=1;
+                                       BitStream[bitnum]= BitStream[bitnum-1];
+                                       bitnum++;
+                               } else {
+                                       //mid value found or no bar supposed to be here
+
+                                       if ((i-lastBit)>(*clk+tol)){
+                                               //should have hit a high or low based on clock!!
+                                               //debug
+                                               //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
+                                               if (bitnum > 0){
+                                                       BitStream[bitnum]=77;
+                                                       bitnum++;
+                                               }
+
+                                               errCnt++;
+                                               lastBit+=*clk;//skip over until hit too many errors
+                                               if (errCnt > ((*size/1000))){  //allow 1 error for every 1000 samples else start over
+                                                       errCnt=0;
+                                                       bitnum=0;//start over
+                                                       break;
+                                               }
+                                       }
+                               }
+                               if (bitnum>500) break;
+                       }
+                       //we got more than 64 good bits and not all errors
+                       if ((bitnum > (64+errCnt)) && (errCnt<(*size/1000))) {
+                               //possible good read
+                               if (errCnt==0) break;  //great read - finish
+                               if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish
+                               if (errCnt<bestErrCnt){  //set this as new best run
+                                       bestErrCnt=errCnt;
+                                       bestStart = iii;
+                               }
+                       }
+               }
+               if (iii>=gLen){ //exhausted test
+                       //if there was a ok test go back to that one and re-run the best run (then dump after that run)
+                       if (bestErrCnt < (*size/1000)) iii=bestStart;
+               }
+       }
+       if (bitnum>16){
+               for (i=0; i < bitnum; ++i){
+                       BinStream[i]=BitStream[i];
+               }
+               *size=bitnum;
+       } else return -1;
+       return errCnt;
 }
-//translate wave to 11111100000 (1 for each short wave 0 for each long wave) 
-size_t fsk_wave_demod(uint8_t * dest, size_t size)
+//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
+size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
 {
        uint32_t last_transition = 0;
        uint32_t idx = 1;
        uint32_t maxVal=0;
-       
+       if (fchigh==0) fchigh=10;
+       if (fclow==0) fclow=8;
        // we do care about the actual theshold value as sometimes near the center of the
        // wave we may get static that changes direction of wave for one value
        // if our value is too low it might affect the read.  and if our tag or
        // antenna is weak a setting too high might not see anything. [marshmellow]
        if (size<100) return 0;
        for(idx=1; idx<100; idx++){
-       if(maxVal<dest[idx]) maxVal = dest[idx];
-    }
-    // set close to the top of the wave threshold with 13% margin for error
-    // less likely to get a false transition up there. 
-    // (but have to be careful not to go too high and miss some short waves)
-       uint8_t threshold_value = (uint8_t)(maxVal*.87);        idx=1;
-               //uint8_t threshold_value = 127;
-       
+               if(maxVal<dest[idx]) maxVal = dest[idx];
+       }
+       // set close to the top of the wave threshold with 25% margin for error
+       // less likely to get a false transition up there.
+       // (but have to be careful not to go too high and miss some short waves)
+       uint8_t threshold_value = (uint8_t)(((maxVal-128)*.75)+128);
+
        // sync to first lo-hi transition, and threshold
 
        // Need to threshold first sample
+
        if(dest[0] < threshold_value) dest[0] = 0;
        else dest[0] = 1;
 
@@ -443,14 +436,15 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size)
        // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
        for(idx = 1; idx < size; idx++) {
                // threshold current value
+
                if (dest[idx] < threshold_value) dest[idx] = 0;
                else dest[idx] = 1;
 
                // Check for 0->1 transition
                if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition
-                       if (idx-last_transition<6){            //0-5 = garbage noise
+                       if ((idx-last_transition)<(fclow-2)){            //0-5 = garbage noise
                                //do nothing with extra garbage
-                       } else if (idx-last_transition <  9) { //6-8 = 8 waves
+                       } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves
                                dest[numBits]=1;
                        } else {                                                        //9+ = 10 waves
                                dest[numBits]=0;
@@ -464,12 +458,13 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size)
 
 uint32_t myround2(float f)
 {
-  if (f >= 2000) return 2000;//something bad happened
-  return (uint32_t) (f + (float)0.5);
+       if (f >= 2000) return 2000;//something bad happened
+       return (uint32_t) (f + (float)0.5);
 }
 
-//translate 11111100000 to 10 
-size_t aggregate_bits(uint8_t *dest,size_t size,  uint8_t rfLen, uint8_t maxConsequtiveBits, uint8_t invert )// uint8_t h2l_crossing_value,uint8_t l2h_crossing_value, 
+//translate 11111100000 to 10
+size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits,
+    uint8_t invert, uint8_t fchigh, uint8_t fclow)
 {
        uint8_t lastval=dest[0];
        uint32_t idx=0;
@@ -484,21 +479,19 @@ size_t aggregate_bits(uint8_t *dest,size_t size,  uint8_t rfLen, uint8_t maxCons
                }
                //if lastval was 1, we have a 1->0 crossing
                if ( dest[idx-1]==1 ) {
-                       n=myround2((float)(n+1)/((float)(rfLen)/(float)8));
-                       //n=(n+1) / h2l_crossing_value;
+                       n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow));
                } else {// 0->1 crossing
-                       n=myround2((float)(n+1)/((float)(rfLen-2)/(float)10));  //-2 for fudge factor
-                       //n=(n+1) / l2h_crossing_value;
+                       n=myround2((float)(n+1)/((float)(rfLen-2)/(float)fchigh));  //-2 for fudge factor
                }
                if (n == 0) n = 1;
 
-               if(n < maxConsequtiveBits) //Consecutive 
+               if(n < maxConsequtiveBits) //Consecutive
                {
-                       if(invert==0){ //invert bits 
+                       if(invert==0){ //invert bits
                                memset(dest+numBits, dest[idx-1] , n);
                        }else{
-                               memset(dest+numBits, dest[idx-1]^1 , n);        
-                       }                       
+                               memset(dest+numBits, dest[idx-1]^1 , n);
+                       }
                        numBits += n;
                }
                n=0;
@@ -508,32 +501,20 @@ size_t aggregate_bits(uint8_t *dest,size_t size,  uint8_t rfLen, uint8_t maxCons
 }
 //by marshmellow  (from holiman's base)
 // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod)
-int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert)
+int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow)
 {
-  //uint8_t h2l_crossing_value = 6;
-  //uint8_t l2h_crossing_value = 5;
-  
-  // if (rfLen==64)  //currently only know settings for RF/64 change from default if option entered
-  // {
-  //   h2l_crossing_value=8;  //or 8  as 64/8 = 8
-  //   l2h_crossing_value=6;  //or 6.4 as 64/10 = 6.4
-  // }
- // size_t size  = GraphTraceLen; 
-    // FSK demodulator
-  size = fsk_wave_demod(dest, size);
-  size = aggregate_bits(dest, size,rfLen,192,invert);
- // size = aggregate_bits(size, h2l_crossing_value, l2h_crossing_value,192, invert); //192=no limit to same values
-  //done messing with GraphBuffer - repaint
-  //RepaintGraphWindow();
-  return size;
+       // FSK demodulator
+       size = fsk_wave_demod(dest, size, fchigh, fclow);
+       size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow);
+       return size;
 }
 // loop to get raw HID waveform then FSK demodulate the TAG ID from it
 int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_t *lo)
 {
-       
+
        size_t idx=0; //, found=0; //size=0,
        // FSK demodulator
-       size = fskdemod(dest, size,50,0);
+       size = fskdemod(dest, size,50,0,10,8);
 
        // final loop, go over previously decoded manchester data and decode into usable tag ID
        // 111000 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0
@@ -542,12 +523,12 @@ int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_
        idx = 0;
        //one scan
        while( idx + sizeof(frame_marker_mask) < size) {
-       // search for a start of frame marker
+               // search for a start of frame marker
                if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
                { // frame marker found
                        idx+=sizeof(frame_marker_mask);
                        while(dest[idx] != dest[idx+1] && idx < size-2)
-                       {       
+                       {
                                // Keep going until next frame marker (or error)
                                // Shift in a bit. Start by shifting high registers
                                *hi2 = (*hi2<<1)|(*hi>>31);
@@ -565,7 +546,7 @@ int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_
                        {
                                if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
                                {
-                                       //good return 
+                                       //good return
                                        return idx;
                                }
                        }
@@ -579,7 +560,7 @@ int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_
        return -1;
 }
 
-uint32_t bytebits_to_byte(uint8_t* src, int numbits)
+uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
 {
        uint32_t num = 0;
        for(int i = 0 ; i < numbits ; i++)
@@ -592,103 +573,447 @@ uint32_t bytebits_to_byte(uint8_t* src, int numbits)
 
 int IOdemodFSK(uint8_t *dest, size_t size)
 {
-  uint32_t idx=0;
+       static const uint8_t THRESHOLD = 140;
+       uint32_t idx=0;
        //make sure buffer has data
-       if (size < 64) return -1;
+       if (size < 66) return -1;
        //test samples are not just noise
-       uint8_t testMax=0;
-       for(idx=0;idx<64;idx++){
-               if (testMax<dest[idx]) testMax=dest[idx];
-       }
-       idx=0;
-       //if not just noise
-       if (testMax>170){
-               // FSK demodulator
-               size = fskdemod(dest, size,64,1);
-               //Index map
-               //0           10          20          30          40          50          60
-               //|           |           |           |           |           |           |
-               //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
-               //-----------------------------------------------------------------------------
-               //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11
-               //
-               //XSF(version)facility:codeone+codetwo
-               //Handle the data
-         uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1};
-               for( idx=0; idx < (size - 74); idx++) {
-       if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
-               //frame marker found
-               if (!dest[idx+8] && dest[idx+17]==1 && dest[idx+26]==1 && dest[idx+35]==1 && dest[idx+44]==1 && dest[idx+53]==1){
-                       //confirmed proper separator bits found
-                       //return start position
-                                       return (int) idx;
-                               }
-                       }               
+       uint8_t justNoise = 1;
+       for(idx=0;idx< size && justNoise ;idx++){
+               justNoise = dest[idx] < THRESHOLD;
+       }
+       if(justNoise) return 0;
+
+       // FSK demodulator
+       size = fskdemod(dest, size, 64, 1, 10, 8);  //  RF/64 and invert
+       if (size < 65) return -1;  //did we get a good demod?
+       //Index map
+       //0           10          20          30          40          50          60
+       //|           |           |           |           |           |           |
+       //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
+       //-----------------------------------------------------------------------------
+       //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11
+       //
+       //XSF(version)facility:codeone+codetwo
+       //Handle the data
+       uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1};
+       for( idx=0; idx < (size - 65); idx++) {
+               if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
+                       //frame marker found
+                       if (!dest[idx+8] && dest[idx+17]==1 && dest[idx+26]==1 && dest[idx+35]==1 && dest[idx+44]==1 && dest[idx+53]==1){
+                               //confirmed proper separator bits found
+                               //return start position
+                               return (int) idx;
+                       }
                }
-       }       
+       }
        return 0;
 }
 
 // by marshmellow
 // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping)
 // maybe somehow adjust peak trimming value based on samples to fix?
-int DetectClock2(uint8_t dest[], size_t size, int clock)
+int DetectASKClock(uint8_t dest[], size_t size, int clock)
 {
-  int i=0;
-  int peak=0;
-  int low=0;
-  int clk[]={16,32,40,50,64,100,128,256};
-  for (;i<8;++i)
-       if (clk[i]==clock) return clock;
-  if (!peak){
-    for (i=0;i<size;++i){
-      if(dest[i]>peak){
-        peak = dest[i]; 
-      }
-      if(dest[i]<low){
-        low = dest[i];
-      }
-    }
-    peak=(int)(peak*.75);
-    low= (int)(low*.75);
-  }
-  int ii;
-  int loopCnt = 256;
-  if (size<loopCnt) loopCnt = size;
-  int clkCnt;
-  int tol = 0;
-  int bestErr=1000;
-  int errCnt[]={0,0,0,0,0,0,0,0};
-  for(clkCnt=0; clkCnt<6;++clkCnt){
-    if (clk[clkCnt]==32){
-      tol=1;
-    }else{
-      tol=0;
-    }
-    bestErr=1000;
-    for (ii=0; ii<loopCnt; ++ii){
-      if ((dest[ii]>=peak) || (dest[ii]<=low)){
-        errCnt[clkCnt]=0;
-        for (i=0; i<((int)(size/clk[clkCnt])-1); ++i){
-          if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){
-         }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){
-          }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
-          }else{  //error no peak detected
-            errCnt[clkCnt]++;
-          }    
-        }
-        if(errCnt[clkCnt]==0) return clk[clkCnt];
-        if(errCnt[clkCnt]<bestErr) bestErr=errCnt[clkCnt];
-      }
-    } 
-    errCnt[clkCnt]=bestErr;
-  }
-  int iii=0;
-  int best=0;
-  for (iii=0; iii<6;++iii){
-    if (errCnt[iii]<errCnt[best]){
-      best = iii;
-    }
-  }
-  return clk[best];
+       int i=0;
+       int peak=0;
+       int low=128;
+       int clk[]={16,32,40,50,64,100,128,256};
+       int loopCnt = 256;  //don't need to loop through entire array...
+       if (size<loopCnt) loopCnt = size;
+
+       //if we already have a valid clock quit
+       for (;i<8;++i)
+               if (clk[i] == clock) return clock;
+
+       //get high and low peak
+       for (i=0; i < loopCnt; ++i){
+               if(dest[i] > peak){
+                       peak = dest[i];
+               }
+               if(dest[i] < low){
+                       low = dest[i];
+               }
+       }
+       peak=(int)(((peak-128)*.75)+128);
+       low= (int)(((low-128)*.75)+128);
+       int ii;
+       int clkCnt;
+       int tol = 0;
+       int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000};
+       int errCnt=0;
+       //test each valid clock from smallest to greatest to see which lines up
+       for(clkCnt=0; clkCnt < 6; ++clkCnt){
+               if (clk[clkCnt] == 32){
+                       tol=1;
+               }else{
+                       tol=0;
+               }
+               bestErr[clkCnt]=1000;
+               //try lining up the peaks by moving starting point (try first 256)
+               for (ii=0; ii< loopCnt; ++ii){
+                       if ((dest[ii] >= peak) || (dest[ii] <= low)){
+                               errCnt=0;
+                               // now that we have the first one lined up test rest of wave array
+                               for (i=0; i<((int)(size/clk[clkCnt])-1); ++i){
+                                       if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){
+                                       }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){
+                                       }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
+                                       }else{  //error no peak detected
+                                               errCnt++;
+                                       }
+                               }
+                               //if we found no errors this is correct one - return this clock
+                               if(errCnt==0) return clk[clkCnt];
+                               //if we found errors see if it is lowest so far and save it as best run
+                               if(errCnt<bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
+                       }
+               }
+       }
+       int iii=0;
+       int best=0;
+       for (iii=0; iii<7;++iii){
+               if (bestErr[iii]<bestErr[best]){
+                       //                current best bit to error ratio     vs  new bit to error ratio
+                       if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
+                               best = iii;
+                       }
+               }
+       }
+       return clk[best];
+}
+
+//by marshmellow
+//detect psk clock by reading #peaks vs no peaks(or errors)
+int DetectpskNRZClock(uint8_t dest[], size_t size, int clock)
+{
+       int i=0;
+       int peak=0;
+       int low=128;
+       int clk[]={16,32,40,50,64,100,128,256};
+       int loopCnt = 2048;  //don't need to loop through entire array...
+       if (size<loopCnt) loopCnt = size;
+
+       //if we already have a valid clock quit
+       for (; i < 8; ++i)
+               if (clk[i] == clock) return clock;
+
+       //get high and low peak
+       for (i=0; i < loopCnt; ++i){
+               if(dest[i] > peak){
+                       peak = dest[i];
+               }
+               if(dest[i] < low){
+                       low = dest[i];
+               }
+       }
+       peak=(int)(((peak-128)*.90)+128);
+       low= (int)(((low-128)*.90)+128);
+       //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low);
+       int ii;
+       uint8_t clkCnt;
+       uint8_t tol = 0;
+       int peakcnt=0;
+       int errCnt=0;
+       int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
+       int peaksdet[]={0,0,0,0,0,0,0,0,0};
+       //test each valid clock from smallest to greatest to see which lines up
+       for(clkCnt=0; clkCnt < 6; ++clkCnt){
+               if (clk[clkCnt] == 32){
+                       tol=0;
+               }else{
+                       tol=0;
+               }
+               //try lining up the peaks by moving starting point (try first 256)
+               for (ii=0; ii< loopCnt; ++ii){
+                       if ((dest[ii] >= peak) || (dest[ii] <= low)){
+                               errCnt=0;
+                               peakcnt=0;
+                               // now that we have the first one lined up test rest of wave array
+                               for (i=0; i < ((int)(size/clk[clkCnt])-1); ++i){
+                                       if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){
+                                               peakcnt++;
+                                       }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){
+                                               peakcnt++;
+                                       }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
+                                               peakcnt++;
+                                       }else{  //error no peak detected
+                                               errCnt++;
+                                       }
+                               }
+                               if(peakcnt>peaksdet[clkCnt]) {
+                                       peaksdet[clkCnt]=peakcnt;
+                                       bestErr[clkCnt]=errCnt;
+                               }
+                       }
+               }
+       }
+       int iii=0;
+       int best=0;
+       //int ratio2;  //debug
+       int ratio;
+       //int bits;
+       for (iii=0; iii < 7; ++iii){
+               ratio=1000;
+               //ratio2=1000;  //debug
+               //bits=size/clk[iii];  //debug
+               if (peaksdet[iii] > 0){
+                       ratio=bestErr[iii]/peaksdet[iii];
+                       if (((bestErr[best]/peaksdet[best]) > (ratio)+1)){
+                               best = iii;
+                       }
+                       //ratio2=bits/peaksdet[iii]; //debug
+               }
+               //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d, ratio: %d, bits: %d, peakbitr: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best],ratio, bits,ratio2);
+       }
+       return clk[best];
+}
+
+//by marshmellow (attempt to get rid of high immediately after a low)
+void pskCleanWave(uint8_t *bitStream, size_t size)
+{
+       int i;
+       int low=128;
+       int high=0;
+       int gap = 4;
+ // int loopMax = 2048;
+       int newLow=0;
+       int newHigh=0;
+       for (i=0; i < size; ++i){
+               if (bitStream[i] < low) low=bitStream[i];
+               if (bitStream[i] > high) high=bitStream[i];
+       }
+       high = (int)(((high-128)*.80)+128);
+       low = (int)(((low-128)*.90)+128);
+       //low = (uint8_t)(((int)(low)-128)*.80)+128;
+       for (i=0; i < size; ++i){
+               if (newLow == 1){
+                       bitStream[i]=low+8;
+                       gap--;
+                       if (gap == 0){
+                               newLow=0;
+                               gap=4;
+                       }
+               }else if (newHigh == 1){
+                       bitStream[i]=high-8;
+                       gap--;
+                       if (gap == 0){
+                               newHigh=0;
+                               gap=4;
+                       }
+               }
+               if (bitStream[i] <= low) newLow=1;
+               if (bitStream[i] >= high) newHigh=1;
+       }
+       return;
+}
+
+
+//redesigned by marshmellow adjusted from existing decode functions
+//indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
+int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
+{
+       //26 bit 40134 format  (don't know other formats)
+       int i;
+       int long_wait;
+       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;
+       }
+       //found start once now test length by finding next one
+       // Inverting signal if needed
+       if (first == 1) {
+               for (i = start; i < *size; i++) {
+                       bitStream[i] = !bitStream[i];
+               }
+               *invert = 1;
+       }else *invert=0;
+
+       int iii;
+       for (ii=start+29; ii <= *size - 250; ii++) {
+               first2 = bitStream[ii];
+               for (iii = ii; iii < ii + long_wait; iii++) {
+                       if (bitStream[iii] != first2) {
+                               break;
+                       }
+               }
+               if (iii == (ii + long_wait)) {
+                       break;
+               }
+       }
+       if (ii== *size - 250 + 1){
+               // did not find second start sequence
+               return -2;
+       }
+       bitCnt=ii-start;
+
+       // Dumping UID
+       i = start;
+       for (ii = 0; ii < bitCnt; ii++) {
+               bitStream[ii] = bitStream[i++];
+       }
+       *size=bitCnt;
+       return 1;
 }
+
+
+//by marshmellow - demodulate PSK wave or NRZ wave (both similar enough)
+//peaks switch bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
+int pskNRZrawDemod(uint8_t *dest, size_t *size, int *clk, int *invert)
+{
+       pskCleanWave(dest,*size);
+       int clk2 = DetectpskNRZClock(dest, *size, *clk);
+       *clk=clk2;
+       uint32_t i;
+       uint8_t high=0, low=128;
+       uint32_t gLen = *size;
+       if (gLen > 1280) gLen=1280;
+       // get high
+       for (i=0; i < gLen; ++i){
+               if (dest[i] > high) high = dest[i];
+               if (dest[i] < low) low = dest[i];
+       }
+       //fudge high/low bars by 25%
+       high = (uint8_t)((((int)(high)-128)*.75)+128);
+       low = (uint8_t)((((int)(low)-128)*.80)+128);
+
+       //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
+       int lastBit = 0;  //set first clock check
+       uint32_t bitnum = 0;     //output counter
+       uint8_t tol = 0;  //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
+       if (*clk==32)tol=2;    //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
+       uint32_t iii = 0;
+       uint8_t errCnt =0;
+       uint32_t bestStart = *size;
+       uint32_t maxErr = (*size/1000);
+       uint32_t bestErrCnt = maxErr;
+       //uint8_t midBit=0;
+       uint8_t curBit=0;
+       uint8_t bitHigh=0;
+       uint8_t ignorewin=*clk/8;
+       //PrintAndLog("DEBUG - lastbit - %d",lastBit);
+       //loop to find first wave that works - align to clock
+       for (iii=0; iii < gLen; ++iii){
+               if ((dest[iii]>=high) || (dest[iii]<=low)){
+                       lastBit=iii-*clk;
+                       //loop through to see if this start location works
+                       for (i = iii; i < *size; ++i) {
+                               //if we found a high bar and we are at a clock bit
+                               if ((dest[i]>=high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
+                                       bitHigh=1;
+                                       lastBit+=*clk;
+                                       ignorewin=*clk/8;
+                                       bitnum++;
+                               //else if low bar found and we are at a clock point
+                               }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
+                                       bitHigh=1;
+                                       lastBit+=*clk;
+                                       ignorewin=*clk/8;
+                                       bitnum++;
+                               //else if no bars found
+                               }else if(dest[i] < high && dest[i] > low) {
+                                       if (ignorewin==0){
+                                               bitHigh=0;
+                                       }else ignorewin--;
+                                                                               //if we are past a clock point
+                                       if (i >= lastBit+*clk+tol){ //clock val
+                                               lastBit+=*clk;
+                                               bitnum++;
+                                       }
+                               //else if bar found but we are not at a clock bit and we did not just have a clock bit
+                               }else if ((dest[i]>=high || dest[i]<=low) && (i<lastBit+*clk-tol || i>lastBit+*clk+tol) && (bitHigh==0)){
+                                       //error bar found no clock...
+                                       errCnt++;
+                               }
+                               if (bitnum>=1000) break;
+                       }
+                       //we got more than 64 good bits and not all errors
+                       if ((bitnum > (64+errCnt)) && (errCnt < (maxErr))) {
+                               //possible good read
+                               if (errCnt == 0){
+                                       bestStart = iii;
+                                       bestErrCnt = errCnt;
+                                       break;  //great read - finish
+                               }
+                               if (bestStart == iii) break;  //if current run == bestErrCnt run (after exhausted testing) then finish
+                               if (errCnt < bestErrCnt){  //set this as new best run
+                                       bestErrCnt = errCnt;
+                                       bestStart = iii;
+                               }
+                       }
+               }
+       }
+       if (bestErrCnt < maxErr){
+               //best run is good enough set to best run and set overwrite BinStream
+               iii=bestStart;
+               lastBit=bestStart-*clk;
+               bitnum=0;
+               for (i = iii; i < *size; ++i) {
+                       //if we found a high bar and we are at a clock bit
+                       if ((dest[i] >= high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
+                               bitHigh=1;
+                               lastBit+=*clk;
+                               curBit=1-*invert;
+                               dest[bitnum]=curBit;
+                               ignorewin=*clk/8;
+                               bitnum++;
+                       //else if low bar found and we are at a clock point
+                       }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
+                               bitHigh=1;
+                               lastBit+=*clk;
+                               curBit=*invert;
+                               dest[bitnum]=curBit;
+                               ignorewin=*clk/8;
+                               bitnum++;
+                       //else if no bars found
+                       }else if(dest[i]<high && dest[i]>low) {
+                               if (ignorewin==0){
+                                       bitHigh=0;
+                               }else ignorewin--;
+                               //if we are past a clock point
+                               if (i>=lastBit+*clk+tol){ //clock val
+                                       lastBit+=*clk;
+                                       dest[bitnum]=curBit;
+                                       bitnum++;
+                               }
+                       //else if bar found but we are not at a clock bit and we did not just have a clock bit
+                       }else if ((dest[i]>=high || dest[i]<=low) && ((i<lastBit+*clk-tol) || (i>lastBit+*clk+tol)) && (bitHigh==0)){
+                               //error bar found no clock...
+                               bitHigh=1;
+                               dest[bitnum]=77;
+                               bitnum++;
+                               errCnt++;
+                       }
+                       if (bitnum >=1000) break;
+               }
+               *size=bitnum;
+       } else{
+               *size=bitnum;
+               *clk=bestStart;
+               return -1;
+       }
+
+       if (bitnum>16){
+               *size=bitnum;
+       } else return -1;
+       return errCnt;
+}
+
Impressum, Datenschutz