#include <stdlib.h>
#include <string.h>
#include "lfdemod.h"
-
-
uint8_t justNoise(uint8_t *BitStream, size_t size)
{
static const uint8_t THRESHOLD = 123;
*high=0;
*low=255;
// get high and low thresholds
- for (int i=0; i < size; i++){
+ for (size_t i=0; i < size; i++){
if (BitStream[i] > *high) *high = BitStream[i];
if (BitStream[i] < *low) *low = BitStream[i];
}
if (*high < 123) return -1; // just noise
*high = ((*high-128)*fuzzHi + 12800)/100;
- *low = ((*low-128)*fuzzLo + 12800)/100;
+ *low = ((*low-128)*fuzzLo + 12800)/100;
return 1;
}
// otherwise could be a void with no arguments
//set defaults
uint32_t i = 0;
- if (BitStream[1]>1){ //allow only 1s and 0s
- // PrintAndLog("no data found");
- return 0;
- }
+ if (BitStream[1]>1) return 0; //allow only 1s and 0s
+
// 111111111 bit pattern represent start of frame
// include 0 in front to help get start pos
uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
idx = *startIdx + 9;
for (i=0; i<FmtLen; i++){ //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits)
parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5);
- //check even parity
- if (parityTest(parityBits, 5, 0) == 0){
- //parity failed quit
- return 0;
- }
+ //check even parity - quit if failed
+ if (parityTest(parityBits, 5, 0) == 0) return 0;
//set uint64 with ID from BitStream
for (uint8_t ii=0; ii<4; ii++){
*hi = (*hi << 1) | (*lo >> 63);
}
//by marshmellow
-//takes 3 arguments - clock, invert, maxErr as integers
-//attempts to demodulate ask while decoding manchester
-//prints binary found and saves in graphbuffer for further commands
-int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr)
+//demodulates strong heavily clipped samples
+int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low)
{
- int i;
- //int clk2=*clk;
- int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
- if (*clk==0) return -3;
- if (start < 0) return -3;
- // if autodetected too low then adjust //MAY NEED ADJUSTMENT
- //if (clk2==0 && *clk<8) *clk =64;
- //if (clk2==0 && *clk<32) *clk=32;
- if (*invert != 0 && *invert != 1) *invert=0;
- uint32_t initLoopMax = 200;
- if (initLoopMax > *size) initLoopMax=*size;
- // Detect high and lows
- // 25% fuzz in case highs and lows aren't clipped [marshmellow]
- int high, low, ans;
- ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75);
- if (ans<1) return -2; //just noise
-
- // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
- int lastBit = 0; //set first clock check
- uint32_t bitnum = 0; //output counter
- int tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
- if (*clk<=32) tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
- int iii = 0;
- uint32_t gLen = *size;
- if (gLen > 3000) gLen=3000;
- //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
- if (!maxErr) gLen=*clk*2;
- uint8_t errCnt =0;
- uint16_t MaxBits = 500;
- uint32_t bestStart = *size;
- int bestErrCnt = maxErr+1;
- // PrintAndLog("DEBUG - lastbit - %d",lastBit);
- // loop to find first wave that works
- for (iii=0; iii < gLen; ++iii){
- if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){
- lastBit=iii-*clk;
- errCnt=0;
- // loop through to see if this start location works
- for (i = iii; i < *size; ++i) {
- if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
- lastBit+=*clk;
- } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
- //low found and we are expecting a bar
- lastBit+=*clk;
- } else {
- //mid value found or no bar supposed to be here
- if ((i-lastBit)>(*clk+tol)){
- //should have hit a high or low based on clock!!
-
- //debug
- //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-
+ size_t bitCnt=0, smplCnt=0, errCnt=0;
+ uint8_t waveHigh = 0;
+ for (size_t i=0; i < *size; i++){
+ if (BinStream[i] >= high && waveHigh){
+ smplCnt++;
+ } else if (BinStream[i] <= low && !waveHigh){
+ smplCnt++;
+ } else { //transition
+ if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
+ if (smplCnt > clk-(clk/4)-1) { //full clock
+ if (smplCnt > clk + (clk/4)+1) { //too many samples
errCnt++;
- lastBit+=*clk;//skip over until hit too many errors
- if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over
+ BinStream[bitCnt++]=7;
+ } else if (waveHigh) {
+ BinStream[bitCnt++] = invert;
+ BinStream[bitCnt++] = invert;
+ } else if (!waveHigh) {
+ BinStream[bitCnt++] = invert ^ 1;
+ BinStream[bitCnt++] = invert ^ 1;
}
+ waveHigh ^= 1;
+ smplCnt = 0;
+ } else if (smplCnt > (clk/2) - (clk/4)-1) {
+ if (waveHigh) {
+ BinStream[bitCnt++] = invert;
+ } else if (!waveHigh) {
+ BinStream[bitCnt++] = invert ^ 1;
+ }
+ waveHigh ^= 1;
+ smplCnt = 0;
+ } else if (!bitCnt) {
+ //first bit
+ waveHigh = (BinStream[i] >= high);
+ smplCnt = 1;
+ } else {
+ smplCnt++;
+ //transition bit oops
}
- if ((i-iii) >(MaxBits * *clk)) break; //got plenty of bits
- }
- //we got more than 64 good bits and not all errors
- if ((((i-iii)/ *clk) > (64)) && (errCnt<=maxErr)) {
- //possible good read
- if (errCnt==0){
- bestStart=iii;
- bestErrCnt=errCnt;
- break; //great read - finish
- }
- if (errCnt<bestErrCnt){ //set this as new best run
- bestErrCnt=errCnt;
- bestStart = iii;
- }
+ } else { //haven't hit new high or new low yet
+ smplCnt++;
}
}
}
- if (bestErrCnt<=maxErr){
- //best run is good enough set to best run and set overwrite BinStream
- iii=bestStart;
- lastBit = bestStart - *clk;
- bitnum=0;
- for (i = iii; i < *size; ++i) {
- if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
- lastBit += *clk;
- BinStream[bitnum] = *invert;
- bitnum++;
- } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
- //low found and we are expecting a bar
- lastBit+=*clk;
- BinStream[bitnum] = 1-*invert;
- bitnum++;
- } else {
- //mid value found or no bar supposed to be here
- if ((i-lastBit)>(*clk+tol)){
- //should have hit a high or low based on clock!!
-
- //debug
- //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
- if (bitnum > 0){
- BinStream[bitnum]=77;
- bitnum++;
- }
+ *size = bitCnt;
+ return errCnt;
+}
- lastBit+=*clk;//skip over error
- }
- }
- if (bitnum >=MaxBits) break;
- }
- *size=bitnum;
- } else{
- *invert=bestStart;
- *clk=iii;
- return -1;
+//by marshmellow
+void askAmp(uint8_t *BitStream, size_t size)
+{
+ for(size_t i = 1; i<size; i++){
+ if (BitStream[i]-BitStream[i-1]>=30) //large jump up
+ BitStream[i]=127;
+ else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down
+ BitStream[i]=-127;
}
- return bestErrCnt;
+ return;
}
//by marshmellow
-//encode binary data into binary manchester
-int ManchesterEncode(uint8_t *BitStream, size_t size)
+//attempts to demodulate ask modulations, askType == 0 for ask/raw, askType==1 for ask/manchester
+int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp, uint8_t askType)
{
- size_t modIdx=20000, i=0;
- if (size>modIdx) return -1;
- for (size_t idx=0; idx < size; idx++){
- BitStream[idx+modIdx++] = BitStream[idx];
- BitStream[idx+modIdx++] = BitStream[idx]^1;
+ if (*size==0) return -1;
+ int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default
+ if (*clk==0 || start < 0) return -3;
+ if (*invert != 1) *invert = 0;
+ if (amp==1) askAmp(BinStream, *size);
+
+ uint8_t initLoopMax = 255;
+ if (initLoopMax > *size) initLoopMax = *size;
+ // Detect high and lows
+ //25% clip in case highs and lows aren't clipped [marshmellow]
+ int high, low;
+ if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1)
+ return -2; //just noise
+
+ size_t errCnt = 0;
+ // if clean clipped waves detected run alternate demod
+ if (DetectCleanAskWave(BinStream, *size, high, low)) {
+ errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
+ if (askType) //askman
+ return manrawdecode(BinStream, size, 0);
+ else //askraw
+ return errCnt;
}
- for (; i<(size*2); i++){
- BitStream[i] = BitStream[i+20000];
+
+ int lastBit; //set first clock check - can go negative
+ size_t i, bitnum = 0; //output counter
+ uint8_t midBit = 0;
+ uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
+ if (*clk <= 32) tol = 1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
+ size_t MaxBits = 1024;
+ lastBit = start - *clk;
+
+ for (i = start; i < *size; ++i) {
+ if (i-lastBit >= *clk-tol){
+ if (BinStream[i] >= high) {
+ BinStream[bitnum++] = *invert;
+ } else if (BinStream[i] <= low) {
+ BinStream[bitnum++] = *invert ^ 1;
+ } else if (i-lastBit >= *clk+tol) {
+ if (bitnum > 0) {
+ BinStream[bitnum++]=7;
+ errCnt++;
+ }
+ } else { //in tolerance - looking for peak
+ continue;
+ }
+ midBit = 0;
+ lastBit += *clk;
+ } else if (i-lastBit >= (*clk/2-tol) && !midBit && !askType){
+ if (BinStream[i] >= high) {
+ BinStream[bitnum++] = *invert;
+ } else if (BinStream[i] <= low) {
+ BinStream[bitnum++] = *invert ^ 1;
+ } else if (i-lastBit >= *clk/2+tol) {
+ BinStream[bitnum] = BinStream[bitnum-1];
+ bitnum++;
+ } else { //in tolerance - looking for peak
+ continue;
+ }
+ midBit = 1;
+ }
+ if (bitnum >= MaxBits) break;
}
- return i;
+ *size = bitnum;
+ return errCnt;
}
//by marshmellow
//take 10 and 01 and manchester decode
//run through 2 times and take least errCnt
-int manrawdecode(uint8_t * BitStream, size_t *size)
+int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert)
{
uint16_t bitnum=0, MaxBits = 512, errCnt = 0;
size_t i, ii;
uint16_t bestErr = 1000, bestRun = 0;
- if (size == 0) return -1;
+ if (*size < 16) return -1;
+ //find correct start position [alignment]
for (ii=0;ii<2;++ii){
- i=0;
- for (i=i+ii;i<*size-2;i+=2){
- if(BitStream[i]==1 && (BitStream[i+1]==0)){
- } else if((BitStream[i]==0)&& BitStream[i+1]==1){
- } else {
+ for (i=ii; i<*size-3; i+=2)
+ if (BitStream[i]==BitStream[i+1])
errCnt++;
- }
- if(bitnum>MaxBits) break;
- }
+
if (bestErr>errCnt){
bestErr=errCnt;
bestRun=ii;
}
errCnt=0;
}
- errCnt=bestErr;
- if (errCnt<20){
- ii=bestRun;
- i=0;
- for (i=i+ii; i < *size-2; i+=2){
- if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
- BitStream[bitnum++]=0;
- } else if((BitStream[i] == 0) && BitStream[i+1] == 1){
- BitStream[bitnum++]=1;
- } else {
- BitStream[bitnum++]=77;
- //errCnt++;
- }
- if(bitnum>MaxBits) break;
+ //decode
+ for (i=bestRun; i < *size-3; i+=2){
+ if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
+ BitStream[bitnum++]=invert;
+ } else if((BitStream[i] == 0) && BitStream[i+1] == 1){
+ BitStream[bitnum++]=invert^1;
+ } else {
+ BitStream[bitnum++]=7;
}
- *size=bitnum;
+ if(bitnum>MaxBits) break;
}
- return errCnt;
+ *size=bitnum;
+ return bestErr;
+}
+
+//by marshmellow
+//encode binary data into binary manchester
+int ManchesterEncode(uint8_t *BitStream, size_t size)
+{
+ size_t modIdx=20000, i=0;
+ if (size>modIdx) return -1;
+ for (size_t idx=0; idx < size; idx++){
+ BitStream[idx+modIdx++] = BitStream[idx];
+ BitStream[idx+modIdx++] = BitStream[idx]^1;
+ }
+ for (; i<(size*2); i++){
+ BitStream[i] = BitStream[i+20000];
+ }
+ return i;
}
//by marshmellow
//decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding
int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert)
{
- uint16_t bitnum=0;
- uint32_t errCnt =0;
- size_t i=offset;
+ uint16_t bitnum = 0;
+ uint16_t errCnt = 0;
+ size_t i = offset;
uint16_t MaxBits=512;
//if not enough samples - error
if (*size < 51) return -1;
for (i=offset; i<*size-3; i+=2){
//check for phase error
if (BitStream[i+1]==BitStream[i+2]) {
- BitStream[bitnum++]=77;
+ BitStream[bitnum++]=7;
errCnt++;
}
if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){
} else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){
BitStream[bitnum++]=invert;
} else {
- BitStream[bitnum++]=77;
+ BitStream[bitnum++]=7;
errCnt++;
}
if(bitnum>MaxBits) break;
return errCnt;
}
-//by marshmellow
-void askAmp(uint8_t *BitStream, size_t size)
-{
- int shift = 127;
- int shiftedVal=0;
- for(int i = 1; i<size; i++){
- if (BitStream[i]-BitStream[i-1]>=30) //large jump up
- shift=127;
- else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down
- shift=-127;
-
- shiftedVal=BitStream[i]+shift;
-
- if (shiftedVal>255)
- shiftedVal=255;
- else if (shiftedVal<0)
- shiftedVal=0;
- BitStream[i-1] = shiftedVal;
- }
- return;
-}
-
-int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low)
-{
- size_t bitCnt=0, smplCnt=0, errCnt=0;
- uint8_t waveHigh = 0;
- //PrintAndLog("clk: %d", clk);
- for (size_t i=0; i < *size; i++){
- if (BinStream[i] >= high && waveHigh){
- smplCnt++;
- } else if (BinStream[i] <= low && !waveHigh){
- smplCnt++;
- } else { //transition
- if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
- if (smplCnt > clk-(clk/4)-1) { //full clock
- if (smplCnt > clk + (clk/4)+1) { //too many samples
- errCnt++;
- BinStream[bitCnt++]=77;
- } else if (waveHigh) {
- BinStream[bitCnt++] = invert;
- BinStream[bitCnt++] = invert;
- } else if (!waveHigh) {
- BinStream[bitCnt++] = invert ^ 1;
- BinStream[bitCnt++] = invert ^ 1;
- }
- waveHigh ^= 1;
- smplCnt = 0;
- } else if (smplCnt > (clk/2) - (clk/4)-1) {
- if (waveHigh) {
- BinStream[bitCnt++] = invert;
- } else if (!waveHigh) {
- BinStream[bitCnt++] = invert ^ 1;
- }
- waveHigh ^= 1;
- smplCnt = 0;
- } else if (!bitCnt) {
- //first bit
- waveHigh = (BinStream[i] >= high);
- smplCnt = 1;
- } else {
- smplCnt++;
- //transition bit oops
- }
- } else { //haven't hit new high or new low yet
- smplCnt++;
- }
- }
- }
- *size = bitCnt;
- return errCnt;
-}
-
-//by marshmellow
-//takes 3 arguments - clock, invert and maxErr as integers
-//attempts to demodulate ask only
-int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp)
-{
- uint32_t i;
- if (*size==0) return -1;
- int start = DetectASKClock(BinStream, *size, clk, 20); //clock default
- if (*clk==0) return -1;
- if (start<0) return -1;
- if (*invert != 0 && *invert != 1) *invert =0;
- if (amp==1) askAmp(BinStream, *size);
-
- uint32_t initLoopMax = 200;
- if (initLoopMax > *size) initLoopMax=*size;
- // Detect high and lows
- //25% clip in case highs and lows aren't clipped [marshmellow]
- uint8_t clip = 75;
- int high, low, ans;
- ans = getHiLo(BinStream, initLoopMax, &high, &low, clip, clip);
- if (ans<1) return -1; //just noise
-
- if (DetectCleanAskWave(BinStream, *size, high, low)) {
- //PrintAndLog("Clean");
- return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
- }
-
- //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low);
- int lastBit = 0; //set first clock check
- uint32_t bitnum = 0; //output counter
- uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock
- // if they fall + or - this value + clock from last valid wave
- if (*clk == 32) tol=0; //clock tolerance may not be needed anymore currently set to
- // + or - 1 but could be increased for poor waves or removed entirely
- uint32_t iii = 0;
- uint32_t gLen = *size;
- if (gLen > 500) gLen=500;
- //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance
- if (!maxErr) gLen = *clk * 2;
- uint8_t errCnt =0;
- uint32_t bestStart = *size;
- uint32_t bestErrCnt = maxErr; //(*size/1000);
- uint8_t midBit=0;
- uint16_t MaxBits=1000;
-
- //PrintAndLog("DEBUG - lastbit - %d",lastBit);
- //loop to find first wave that works
- for (iii=start; iii < gLen; ++iii){
- if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){
- lastBit=iii-*clk;
- errCnt=0;
- //loop through to see if this start location works
- for (i = iii; i < *size; ++i) {
- if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){
- lastBit+=*clk;
- midBit=0;
- } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){
- //low found and we are expecting a bar
- lastBit+=*clk;
- midBit=0;
- } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
- //mid bar?
- midBit=1;
- } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
- //mid bar?
- midBit=1;
- } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){
- //no mid bar found
- midBit=1;
- } else {
- //mid value found or no bar supposed to be here
-
- if ((i-lastBit)>(*clk+tol)){
- //should have hit a high or low based on clock!!
- //debug
- //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
-
- errCnt++;
- lastBit+=*clk;//skip over until hit too many errors
- if (errCnt > maxErr){
- //errCnt=0;
- break;
- }
- }
- }
- if ((i-iii)>(MaxBits * *clk)) break; //got enough bits
- }
- //we got more than 64 good bits and not all errors
- if ((((i-iii)/ *clk) > (64)) && (errCnt<=maxErr)) {
- //possible good read
- if (errCnt==0){
- bestStart=iii;
- bestErrCnt=errCnt;
- break; //great read - finish
- }
- if (errCnt<bestErrCnt){ //set this as new best run
- bestErrCnt=errCnt;
- bestStart = iii;
- }
- }
- }
- }
- if (bestErrCnt<=maxErr){
- //best run is good enough - set to best run and overwrite BinStream
- iii = bestStart;
- lastBit = bestStart - *clk;
- bitnum=0;
- for (i = iii; i < *size; ++i) {
- if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){
- lastBit += *clk;
- BinStream[bitnum] = *invert;
- bitnum++;
- midBit=0;
- } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){
- //low found and we are expecting a bar
- lastBit+=*clk;
- BinStream[bitnum] = 1 - *invert;
- bitnum++;
- midBit=0;
- } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
- //mid bar?
- midBit=1;
- BinStream[bitnum] = 1 - *invert;
- bitnum++;
- } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){
- //mid bar?
- midBit=1;
- BinStream[bitnum] = *invert;
- bitnum++;
- } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){
- //no mid bar found
- midBit=1;
- if (bitnum!=0) BinStream[bitnum] = BinStream[bitnum-1];
- bitnum++;
-
- } else {
- //mid value found or no bar supposed to be here
- if ((i-lastBit)>(*clk+tol)){
- //should have hit a high or low based on clock!!
-
- //debug
- //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit);
- if (bitnum > 0){
- BinStream[bitnum]=77;
- bitnum++;
- }
- lastBit+=*clk;//skip over error
- }
- }
- if (bitnum >= MaxBits) break;
- }
- *size=bitnum;
- } else{
- *invert=bestStart;
- *clk=iii;
- return -1;
- }
- return bestErrCnt;
-}
-
+// by marshmellow
// demod gProxIIDemod
// error returns as -x
// success returns start position in BitStream
//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
{
- uint32_t last_transition = 0;
- uint32_t idx = 1;
+ size_t last_transition = 0;
+ size_t idx = 1;
//uint32_t maxVal=0;
if (fchigh==0) fchigh=10;
if (fclow==0) fclow=8;
//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;
// sync to first lo-hi transition, and threshold
// Need to threshold first sample
// Check for 0->1 transition
if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition
- if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise
+ preLastSample = LastSample;
+ LastSample = currSample;
+ currSample = idx-last_transition;
+ if (currSample < (fclow-2)){ //0-5 = garbage noise
//do nothing with extra garbage
- } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves
- dest[numBits]=1;
- } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage
+ } else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves
+ if (LastSample > (fchigh-2) && preLastSample < (fchigh-1)){
+ dest[numBits-1]=1; //correct last 9 wave surrounded by 8 waves
+ }
+ dest[numBits++]=1;
+
+ } else if (currSample > (fchigh+1) && !numBits) { //12 + and first bit = garbage
//do nothing with beginning garbage
- } else { //9+ = 10 waves
- dest[numBits]=0;
+ } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's
+ dest[numBits++]=1;
+ } else { //9+ = 10 sample waves
+ dest[numBits++]=0;
}
last_transition = idx;
- numBits++;
}
}
return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0
}
//translate 11111100000 to 10
-size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits,
+size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
uint8_t invert, uint8_t fchigh, uint8_t fclow)
{
uint8_t lastval=dest[0];
- uint32_t idx=0;
+ size_t idx=0;
size_t numBits=0;
uint32_t n=1;
for( idx=1; idx < size; idx++) {
-
- if (dest[idx]==lastval) {
- n++;
- continue;
- }
n++;
+ if (dest[idx]==lastval) continue;
+
//if lastval was 1, we have a 1->0 crossing
if (dest[idx-1]==1) {
if (!numBits && n < rfLen/fclow) {
lastval = dest[idx];
continue;
}
- n = (n * fchigh + rfLen/2) / rfLen; //-1 for fudge factor
+ n = (n * fchigh + rfLen/2) / rfLen;
}
if (n == 0) n = 1;
- if(n < maxConsequtiveBits) //Consecutive
- {
- if(invert==0){ //invert bits
- memset(dest+numBits, dest[idx-1] , n);
- }else{
- memset(dest+numBits, dest[idx-1]^1 , n);
- }
- numBits += n;
- }
+ memset(dest+numBits, dest[idx-1]^invert , n);
+ numBits += n;
n=0;
lastval=dest[idx];
}//end for
-
// if valid extra bits at the end were all the same frequency - add them in
- if (n > rfLen/fclow && n > rfLen/fchigh) {
+ if (n > rfLen/fchigh) {
if (dest[idx-2]==1) {
- n = ((n+1) * fclow + rfLen/2) / rfLen;
- } else {// 0->1 crossing
- n = ((n+1) * fchigh + (rfLen-1)/2) / (rfLen-1); //-1 for fudge factor
+ n = (n * fclow + rfLen/2) / rfLen;
+ } else {
+ n = (n * fchigh + rfLen/2) / rfLen;
}
- memset(dest, dest[idx-1]^invert , n);
+ memset(dest+numBits, dest[idx-1]^invert , n);
numBits += n;
}
return numBits;
{
// FSK demodulator
size = fsk_wave_demod(dest, size, fchigh, fclow);
- size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow);
+ size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow);
return size;
}
size_t numStart=0, size2=*size, startIdx=0;
// FSK demodulator
*size = fskdemod(dest, size2,50,1,10,8); //fsk2a
- if (*size < 96) return -2;
+ if (*size < 96*2) return -2;
// 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
uint8_t preamble[] = {0,0,0,1,1,1,0,1};
// find bitstring in array
return (int)startIdx;
}
-uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
+uint32_t bytebits_to_byte(uint8_t *src, size_t numbits)
{
uint32_t num = 0;
for(int i = 0 ; i < numbits ; i++)
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 num;
+}
+
int IOdemodFSK(uint8_t *dest, size_t size)
{
if (justNoise(dest, size)) return -1;
// 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)
+// Parity Type (1 for odd; 0 for even; 2 Always 1'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)
{
uint32_t parityWd = 0;
parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
BitStream[j++] = (BitStream[startIdx+word+bit]);
}
- j--;
+ j--; // overwrite parity with next data
// if parity fails then return 0
- if (parityTest(parityWd, pLen, pType) == 0) return -1;
+ if (pType == 2) { // then marker bit which should be a 1
+ if (!BitStream[j]) return 0;
+ } else {
+ if (parityTest(parityWd, pLen, pType) == 0) return 0;
+ }
bitCnt+=(pLen-1);
parityWd = 0;
}
return bitCnt;
}
+// Ask/Biphase Demod then try to locate an ISO 11784/85 ID
+// BitStream must contain previously askrawdemod and biphasedemoded data
+int FDXBdemodBI(uint8_t *dest, size_t *size)
+{
+ //make sure buffer has enough data
+ if (*size < 128) return -1;
+
+ size_t startIdx = 0;
+ uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1};
+
+ uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+ if (errChk == 0) return -2; //preamble not found
+ return (int)startIdx;
+}
+
// by marshmellow
// FSK Demod then try to locate an AWID ID
int AWIDdemodFSK(uint8_t *dest, size_t *size)
return (int)startIdx;
}
-
-uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
+// by marshmellow
+// to detect a wave that has heavily clipped (clean) samples
+uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
{
uint16_t allPeaks=1;
uint16_t cntPeaks=0;
- size_t loopEnd = 572;
+ size_t loopEnd = 512+60;
if (loopEnd > size) loopEnd = size;
for (size_t i=60; i<loopEnd; i++){
if (dest[i]>low && dest[i]<high)
return allPeaks;
}
-int DetectStrongAskClock(uint8_t dest[], size_t size)
+// by marshmellow
+// to help detect clocks on heavily clipped samples
+// based on count of low to low
+int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
{
- int clk[]={0,8,16,32,40,50,64,100,128,256};
- size_t idx = 40;
- uint8_t high=0;
- size_t cnt = 0;
- size_t highCnt = 0;
- size_t highCnt2 = 0;
- for (;idx < size; idx++){
- if (dest[idx]>128) {
- if (!high){
- high=1;
- if (cnt > highCnt){
- if (highCnt != 0) highCnt2 = highCnt;
- highCnt = cnt;
- } else if (cnt > highCnt2) {
- highCnt2 = cnt;
- }
- cnt=1;
- } else {
- cnt++;
- }
- } else if (dest[idx] <= 128){
- if (high) {
- high=0;
- if (cnt > highCnt) {
- if (highCnt != 0) highCnt2 = highCnt;
- highCnt = cnt;
- } else if (cnt > highCnt2) {
- highCnt2 = cnt;
- }
- cnt=1;
- } else {
- cnt++;
- }
- }
+ uint8_t fndClk[] = {8,16,32,40,50,64,128};
+ size_t startwave;
+ size_t i = 0;
+ size_t minClk = 255;
+ // get to first full low to prime loop and skip incomplete first pulse
+ while ((dest[i] < high) && (i < size))
+ ++i;
+ while ((dest[i] > low) && (i < size))
+ ++i;
+
+ // loop through all samples
+ while (i < size) {
+ // measure from low to low
+ while ((dest[i] > low) && (i < size))
+ ++i;
+ startwave= i;
+ while ((dest[i] < high) && (i < size))
+ ++i;
+ while ((dest[i] > low) && (i < size))
+ ++i;
+ //get minimum measured distance
+ if (i-startwave < minClk && i < size)
+ minClk = i - startwave;
}
- uint8_t tol;
- for (idx=8; idx>0; idx--){
- tol = clk[idx]/8;
- if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol)
- return clk[idx];
- if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol)
- return clk[idx];
+ // set clock
+ for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
+ if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1)
+ return fndClk[clkCnt];
}
- return -1;
+ return 0;
}
// by marshmellow
// return start index of best starting position for that clock and return clock (by reference)
int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
{
- int i=0;
- int clk[]={8,16,32,40,50,64,100,128,256};
- int loopCnt = 256; //don't need to loop through entire array...
- if (size == 0) return -1;
- if (size<loopCnt) loopCnt = size;
- //if we already have a valid clock quit
-
- for (;i<8;++i)
- if (clk[i] == *clock) return 0;
+ size_t i=1;
+ uint8_t clk[] = {255,8,16,32,40,50,64,100,128,255};
+ uint8_t clkEnd = 9;
+ uint8_t loopCnt = 255; //don't need to loop through entire array...
+ if (size <= loopCnt) return -1; //not enough samples
+
+ //if we already have a valid clock
+ uint8_t clockFnd=0;
+ for (;i<clkEnd;++i)
+ if (clk[i] == *clock) clockFnd = i;
+ //clock found but continue to find best startpos
//get high and low peak
int peak, low;
- getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+ if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1;
//test for large clean peaks
- if (DetectCleanAskWave(dest, size, peak, low)==1){
- int ans = DetectStrongAskClock(dest, size);
- for (i=7; i>0; i--){
- if (clk[i] == ans) {
- *clock=ans;
- return 0;
+ if (!clockFnd){
+ if (DetectCleanAskWave(dest, size, peak, low)==1){
+ int ans = DetectStrongAskClock(dest, size, peak, low);
+ for (i=clkEnd-1; i>0; i--){
+ if (clk[i] == ans) {
+ *clock = ans;
+ //clockFnd = i;
+ return 0; // for strong waves i don't use the 'best start position' yet...
+ //break; //clock found but continue to find best startpos [not yet]
+ }
}
}
}
- int ii;
- int clkCnt;
- int tol = 0;
- int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
- int bestStart[]={0,0,0,0,0,0,0,0,0};
- int errCnt=0;
+
+ uint8_t ii;
+ uint8_t clkCnt, tol = 0;
+ uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
+ uint8_t bestStart[]={0,0,0,0,0,0,0,0,0};
+ size_t errCnt = 0;
+ size_t arrLoc, loopEnd;
+
+ if (clockFnd>0) {
+ clkCnt = clockFnd;
+ clkEnd = clockFnd+1;
+ }
+ else clkCnt=1;
+
//test each valid clock from smallest to greatest to see which lines up
- for(clkCnt=0; clkCnt < 8; clkCnt++){
- if (clk[clkCnt] == 32){
+ for(; clkCnt < clkEnd; clkCnt++){
+ if (clk[clkCnt] <= 32){
tol=1;
}else{
tol=0;
}
- if (!maxErr) loopCnt=clk[clkCnt]*2;
+ //if no errors allowed - keep start within the first clock
+ if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) loopCnt=clk[clkCnt]*2;
bestErr[clkCnt]=1000;
- //try lining up the peaks by moving starting point (try first 256)
+ //try lining up the peaks by moving starting point (try first few clocks)
for (ii=0; ii < loopCnt; ii++){
- if ((dest[ii] >= peak) || (dest[ii] <= low)){
- errCnt=0;
- // now that we have the first one lined up test rest of wave array
- for (i=0; i<((int)((size-ii-tol)/clk[clkCnt])-1); ++i){
- if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){
- }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){
- }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){
- }else{ //error no peak detected
- errCnt++;
- }
- }
- //if we found no errors then we can stop here
- // this is correct one - return this clock
- //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i);
- if(errCnt==0 && clkCnt<6) {
- *clock = clk[clkCnt];
- return ii;
- }
- //if we found errors see if it is lowest so far and save it as best run
- if(errCnt<bestErr[clkCnt]){
- bestErr[clkCnt]=errCnt;
- bestStart[clkCnt]=ii;
+ if (dest[ii] < peak && dest[ii] > low) continue;
+
+ errCnt=0;
+ // now that we have the first one lined up test rest of wave array
+ loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1;
+ for (i=0; i < loopEnd; ++i){
+ arrLoc = ii + (i * clk[clkCnt]);
+ if (dest[arrLoc] >= peak || dest[arrLoc] <= low){
+ }else if (dest[arrLoc-tol] >= peak || dest[arrLoc-tol] <= low){
+ }else if (dest[arrLoc+tol] >= peak || dest[arrLoc+tol] <= low){
+ }else{ //error no peak detected
+ errCnt++;
}
}
+ //if we found no errors then we can stop here and a low clock (common clocks)
+ // this is correct one - return this clock
+ //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i);
+ if(errCnt==0 && clkCnt<7) {
+ if (!clockFnd) *clock = clk[clkCnt];
+ return ii;
+ }
+ //if we found errors see if it is lowest so far and save it as best run
+ if(errCnt<bestErr[clkCnt]){
+ bestErr[clkCnt]=errCnt;
+ bestStart[clkCnt]=ii;
+ }
}
}
- uint8_t iii=0;
+ uint8_t iii;
uint8_t best=0;
- for (iii=0; iii<8; ++iii){
- if (bestErr[iii]<bestErr[best]){
- if (bestErr[iii]==0) bestErr[iii]=1;
+ for (iii=1; iii<clkEnd; ++iii){
+ if (bestErr[iii] < bestErr[best]){
+ if (bestErr[iii] == 0) bestErr[iii]=1;
// current best bit to error ratio vs new bit to error ratio
- if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
+ if ( (size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii] ){
best = iii;
}
}
}
- if (bestErr[best]>maxErr) return -1;
- *clock=clk[best];
+ //if (bestErr[best] > maxErr) return -1;
+ if (!clockFnd) *clock = clk[best];
return bestStart[best];
}
uint16_t peakcnt=0, errCnt=0, waveLenCnt=0;
uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0};
- countFC(dest, size, &fc);
+ fc = countFC(dest, size, 0);
+ if (fc!=2 && fc!=4 && fc!=8) return -1;
//PrintAndLog("DEBUG: FC: %d",fc);
//find first full wave
//detect nrz clock by reading #peaks vs no peaks(or errors)
int DetectNRZClock(uint8_t dest[], size_t size, int clock)
{
- int i=0;
- int clk[]={8,16,32,40,50,64,100,128,256};
- int loopCnt = 4096; //don't need to loop through entire array...
+ size_t i=0;
+ uint8_t clk[]={8,16,32,40,50,64,100,128,255};
+ size_t loopCnt = 4096; //don't need to loop through entire array...
if (size == 0) return 0;
if (size<loopCnt) loopCnt = size;
//get high and low peak
int peak, low;
- getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+ if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0;
//PrintAndLog("DEBUG: peak: %d, low: %d",peak,low);
- int ii;
+ size_t ii;
uint8_t clkCnt;
uint8_t tol = 0;
- int peakcnt=0;
- int peaksdet[]={0,0,0,0,0,0,0,0};
- int maxPeak=0;
+ uint16_t peakcnt=0;
+ uint16_t peaksdet[]={0,0,0,0,0,0,0,0};
+ uint16_t maxPeak=0;
//test for large clipped waves
for (i=0; i<loopCnt; i++){
if (dest[i] >= peak || dest[i] <= low){
}
}
int iii=7;
- int best=0;
+ uint8_t best=0;
for (iii=7; iii > 0; iii--){
if (peaksdet[iii] > peaksdet[best]){
best = iii;
size_t i=1;
uint8_t lastBit=BitStream[0];
for (; i<size; i++){
- if (BitStream[i]==77){
+ if (BitStream[i]==7){
//ignore errors
} else if (lastBit!=BitStream[i]){
lastBit=BitStream[i];
if (justNoise(dest, *size)) return -1;
*clk = DetectNRZClock(dest, *size, *clk);
if (*clk==0) return -2;
- uint32_t i;
- uint32_t gLen = 4096;
+ size_t i, gLen = 4096;
if (gLen>*size) gLen = *size;
int high, low;
if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low
int lastBit = 0; //set first clock check
- uint32_t bitnum = 0; //output counter
+ size_t iii = 0, bitnum = 0; //bitnum counter
+ uint16_t errCnt = 0, MaxBits = 1000;
+ size_t bestErrCnt = maxErr+1;
+ size_t bestPeakCnt = 0, bestPeakStart = 0;
+ uint8_t bestFirstPeakHigh=0, firstPeakHigh=0, curBit=0, bitHigh=0, errBitHigh=0;
uint8_t tol = 1; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
- uint32_t iii = 0;
- uint16_t errCnt =0;
- uint16_t MaxBits = 1000;
- uint32_t bestErrCnt = maxErr+1;
- uint32_t bestPeakCnt = 0;
- uint32_t bestPeakStart=0;
- uint8_t bestFirstPeakHigh=0;
- uint8_t firstPeakHigh=0;
- uint8_t curBit=0;
- uint8_t bitHigh=0;
- uint8_t errBitHigh=0;
uint16_t peakCnt=0;
uint8_t ignoreWindow=4;
- uint8_t ignoreCnt=ignoreWindow; //in case of noice near peak
+ uint8_t ignoreCnt=ignoreWindow; //in case of noise near peak
//loop to find first wave that works - align to clock
for (iii=0; iii < gLen; ++iii){
if ((dest[iii]>=high) || (dest[iii]<=low)){
lastBit=iii-*clk;
peakCnt=0;
errCnt=0;
- bitnum=0;
//loop through to see if this start location works
for (i = iii; i < *size; ++i) {
- //if we found a high bar and we are at a clock bit
- if ((dest[i]>=high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
- bitHigh=1;
- lastBit+=*clk;
- bitnum++;
- peakCnt++;
- errBitHigh=0;
- ignoreCnt=ignoreWindow;
- //else if low bar found and we are at a clock point
- }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
- bitHigh=1;
- lastBit+=*clk;
- bitnum++;
- peakCnt++;
- errBitHigh=0;
- ignoreCnt=ignoreWindow;
+ // if we are at a clock bit
+ if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+ //test high/low
+ if (dest[i] >= high || dest[i] <= low) {
+ bitHigh = 1;
+ peakCnt++;
+ errBitHigh = 0;
+ ignoreCnt = ignoreWindow;
+ lastBit += *clk;
+ } else if (i == lastBit + *clk + tol) {
+ lastBit += *clk;
+ }
//else if no bars found
- }else if(dest[i] < high && dest[i] > low) {
+ } else if (dest[i] < high && dest[i] > low){
if (ignoreCnt==0){
bitHigh=0;
- if (errBitHigh==1){
- errCnt++;
- }
+ if (errBitHigh==1) errCnt++;
errBitHigh=0;
} else {
ignoreCnt--;
}
- //if we are past a clock point
- if (i >= lastBit+*clk+tol){ //clock val
- lastBit+=*clk;
- bitnum++;
- }
- //else if bar found but we are not at a clock bit and we did not just have a clock bit
- }else if ((dest[i]>=high || dest[i]<=low) && (i<lastBit+*clk-tol || i>lastBit+*clk+tol) && (bitHigh==0)){
+ } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) {
//error bar found no clock...
errBitHigh=1;
}
- if (bitnum>=MaxBits) break;
+ if (((i-iii) / *clk)>=MaxBits) break;
}
//we got more than 64 good bits and not all errors
- if (bitnum > (64) && (errCnt <= (maxErr))) {
+ if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) {
//possible good read
- if (errCnt == 0){
- //bestStart = iii;
+ if (!errCnt || peakCnt > bestPeakCnt){
bestFirstPeakHigh=firstPeakHigh;
bestErrCnt = errCnt;
bestPeakCnt = peakCnt;
bestPeakStart = iii;
- break; //great read - finish
- }
- if (errCnt < bestErrCnt){ //set this as new best run
- bestErrCnt = errCnt;
- //bestStart = iii;
+ if (!errCnt) break; //great read - finish
}
- if (peakCnt > bestPeakCnt){
- bestFirstPeakHigh=firstPeakHigh;
- bestPeakCnt=peakCnt;
- bestPeakStart=iii;
- }
}
}
}
//PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart);
- if (bestErrCnt <= maxErr){
- //best run is good enough set to best run and set overwrite BinStream
- iii=bestPeakStart;
- lastBit=bestPeakStart-*clk;
- bitnum=0;
- memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk);
- bitnum += (bestPeakStart / *clk);
- for (i = iii; i < *size; ++i) {
- //if we found a high bar and we are at a clock bit
- if ((dest[i] >= high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
- bitHigh=1;
- lastBit+=*clk;
- curBit=1-*invert;
- dest[bitnum]=curBit;
- bitnum++;
- errBitHigh=0;
- ignoreCnt=ignoreWindow;
- //else if low bar found and we are at a clock point
- }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){
- bitHigh=1;
- lastBit+=*clk;
- curBit=*invert;
- dest[bitnum]=curBit;
- bitnum++;
- errBitHigh=0;
- ignoreCnt=ignoreWindow;
- //else if no bars found
- }else if(dest[i]<high && dest[i]>low) {
- if (ignoreCnt==0){
- bitHigh=0;
- //if peak is done was it an error peak?
- if (errBitHigh==1){
- dest[bitnum]=77;
- bitnum++;
- errCnt++;
- }
- errBitHigh=0;
- } else {
- ignoreCnt--;
- }
- //if we are past a clock point
- if (i>=lastBit+*clk+tol){ //clock val
- lastBit+=*clk;
- dest[bitnum]=curBit;
- bitnum++;
+ if (bestErrCnt > maxErr) return bestErrCnt;
+
+ //best run is good enough set to best run and set overwrite BinStream
+ lastBit = bestPeakStart - *clk;
+ memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk);
+ bitnum += (bestPeakStart / *clk);
+ for (i = bestPeakStart; i < *size; ++i) {
+ // if expecting a clock bit
+ if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+ // test high/low
+ if (dest[i] >= high || dest[i] <= low) {
+ peakCnt++;
+ bitHigh = 1;
+ errBitHigh = 0;
+ ignoreCnt = ignoreWindow;
+ curBit = *invert;
+ if (dest[i] >= high) curBit ^= 1;
+ dest[bitnum++] = curBit;
+ lastBit += *clk;
+ //else no bars found in clock area
+ } else if (i == lastBit + *clk + tol) {
+ dest[bitnum++] = curBit;
+ lastBit += *clk;
+ }
+ //else if no bars found
+ } else if (dest[i] < high && dest[i] > low){
+ if (ignoreCnt == 0){
+ bitHigh = 0;
+ if (errBitHigh == 1){
+ dest[bitnum++] = 7;
+ errCnt++;
}
- //else if bar found but we are not at a clock bit and we did not just have a clock bit
- }else if ((dest[i]>=high || dest[i]<=low) && ((i<lastBit+*clk-tol) || (i>lastBit+*clk+tol)) && (bitHigh==0)){
- //error bar found no clock...
- errBitHigh=1;
+ errBitHigh=0;
+ } else {
+ ignoreCnt--;
}
- if (bitnum >= MaxBits) break;
+ } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) {
+ //error bar found no clock...
+ errBitHigh=1;
}
- *size=bitnum;
- } else{
- *size=bitnum;
- return bestErrCnt;
+ if (bitnum >= MaxBits) break;
}
-
- if (bitnum>16){
- *size=bitnum;
- } else return -5;
- return errCnt;
+ *size = bitnum;
+ return bestErrCnt;
}
//by marshmellow
uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint8_t rfLensFnd = 0;
- uint8_t lastFCcnt=0;
- uint32_t fcCounter = 0;
+ uint8_t lastFCcnt = 0;
+ uint16_t fcCounter = 0;
uint16_t rfCounter = 0;
uint8_t firstBitFnd = 0;
size_t i;
break;
for (; i < size-1; i++){
- if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){
- // new peak
- fcCounter++;
- rfCounter++;
- // if we got less than the small fc + tolerance then set it to the small fc
- if (fcCounter < fcLow+fcTol)
- fcCounter = fcLow;
- else //set it to the large fc
- fcCounter = fcHigh;
-
- //look for bit clock (rf/xx)
- if ((fcCounter<lastFCcnt || fcCounter>lastFCcnt)){
- //not the same size as the last wave - start of new bit sequence
-
- if (firstBitFnd>1){ //skip first wave change - probably not a complete bit
- for (int ii=0; ii<15; ii++){
- if (rfLens[ii]==rfCounter){
- rfCnts[ii]++;
- rfCounter=0;
- break;
- }
- }
- if (rfCounter>0 && rfLensFnd<15){
- //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
- rfCnts[rfLensFnd]++;
- rfLens[rfLensFnd++]=rfCounter;
+ fcCounter++;
+ rfCounter++;
+
+ if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1])
+ continue;
+ // else new peak
+ // if we got less than the small fc + tolerance then set it to the small fc
+ if (fcCounter < fcLow+fcTol)
+ fcCounter = fcLow;
+ else //set it to the large fc
+ fcCounter = fcHigh;
+
+ //look for bit clock (rf/xx)
+ if ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){
+ //not the same size as the last wave - start of new bit sequence
+ if (firstBitFnd > 1){ //skip first wave change - probably not a complete bit
+ for (int ii=0; ii<15; ii++){
+ if (rfLens[ii] == rfCounter){
+ rfCnts[ii]++;
+ rfCounter = 0;
+ break;
}
- } else {
- firstBitFnd++;
}
- rfCounter=0;
- lastFCcnt=fcCounter;
+ if (rfCounter > 0 && rfLensFnd < 15){
+ //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
+ rfCnts[rfLensFnd]++;
+ rfLens[rfLensFnd++] = rfCounter;
+ }
+ } else {
+ firstBitFnd++;
}
- fcCounter=0;
- } else {
- // count sample
- fcCounter++;
- rfCounter++;
+ rfCounter=0;
+ lastFCcnt=fcCounter;
}
+ fcCounter=0;
}
uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15;
//countFC is to detect the field clock lengths.
//counts and returns the 2 most common wave lengths
//mainly used for FSK field clock detection
-uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t *mostFC)
+uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
{
uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0};
uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0};
uint8_t fcLensFnd = 0;
uint8_t lastFCcnt=0;
- uint32_t fcCounter = 0;
+ uint8_t fcCounter = 0;
size_t i;
if (size == 0) return 0;
if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){
// new up transition
fcCounter++;
-
- //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8)
- if (lastFCcnt==5 && fcCounter==9) fcCounter--;
- //if odd and not rc/5 add one (for when we get a fc 9 instead of 10)
- if ((fcCounter==9 && fcCounter & 1) || fcCounter==4) fcCounter++;
-
+ if (fskAdj){
+ //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8)
+ if (lastFCcnt==5 && fcCounter==9) fcCounter--;
+ //if fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5)
+ if ((fcCounter==9) || fcCounter==4) fcCounter++;
// save last field clock count (fc/xx)
+ lastFCcnt = fcCounter;
+ }
// find which fcLens to save it to:
for (int ii=0; ii<10; ii++){
if (fcLens[ii]==fcCounter){
fcL=fcLens[best1];
}
- *mostFC=fcLens[best1];
// TODO: take top 3 answers and compare to known Field clocks to get top 2
uint16_t fcs = (((uint16_t)fcH)<<8) | fcL;
// PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]);
-
- return fcs;
-}
-
-//by marshmellow
-//countPSK_FC is to detect the psk carrier clock length.
-//counts and returns the 1 most common wave length
-uint8_t countPSK_FC(uint8_t *BitStream, size_t size)
-{
- uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0};
- uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0};
- uint8_t fcLensFnd = 0;
- uint32_t fcCounter = 0;
- size_t i;
- if (size == 0) return 0;
-
- // prime i to first up transition
- for (i = 1; i < size-1; i++)
- if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1])
- break;
-
- for (; i < size-1; i++){
- if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){
- // new up transition
- fcCounter++;
-
- // save last field clock count (fc/xx)
- // find which fcLens to save it to:
- for (int ii=0; ii<10; ii++){
- if (fcLens[ii]==fcCounter){
- fcCnts[ii]++;
- fcCounter=0;
- break;
- }
- }
- if (fcCounter>0 && fcLensFnd<10){
- //add new fc length
- fcCnts[fcLensFnd]++;
- fcLens[fcLensFnd++]=fcCounter;
- }
- fcCounter=0;
- } else {
- // count sample
- fcCounter++;
- }
- }
-
- uint8_t best1=9;
- uint16_t maxCnt1=0;
- // go through fclens and find which ones are bigest
- for (i=0; i<10; i++){
- //PrintAndLog("DEBUG: FC %d, Cnt %d",fcLens[i],fcCnts[i]);
- // get the best FC value
- if (fcCnts[i]>maxCnt1) {
- maxCnt1=fcCnts[i];
- best1=i;
- }
- }
- return fcLens[best1];
+ if (fskAdj) return fcs;
+ return fcLens[best1];
}
//by marshmellow - demodulate PSK1 wave
//uses wave lengths (# Samples)
int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
{
- uint16_t loopCnt = 4096; //don't need to loop through entire array...
if (size == 0) return -1;
+ uint16_t loopCnt = 4096; //don't need to loop through entire array...
if (*size<loopCnt) loopCnt = *size;
uint8_t curPhase = *invert;
size_t i, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
uint8_t fc=0, fullWaveLen=0, tol=1;
uint16_t errCnt=0, waveLenCnt=0;
- fc = countPSK_FC(dest, *size);
+ fc = countFC(dest, *size, 0);
if (fc!=2 && fc!=4 && fc!=8) return -1;
//PrintAndLog("DEBUG: FC: %d",fc);
*clock = DetectPSKClock(dest, *size, *clock);
- if (*clock==0) return -1;
+ if (*clock == 0) return -1;
int avgWaveVal=0, lastAvgWaveVal=0;
//find first phase shift
for (i=0; i<loopCnt; i++){
firstFullWave = waveStart;
fullWaveLen=waveLenCnt;
//if average wave value is > graph 0 then it is an up wave or a 1
- if (lastAvgWaveVal > 123) curPhase^=1; //fudge graph 0 a little 123 vs 128
+ if (lastAvgWaveVal > 123) curPhase ^= 1; //fudge graph 0 a little 123 vs 128
break;
}
waveStart = i+1;
avgWaveVal = 0;
}
- avgWaveVal+=dest[i+2];
+ avgWaveVal += dest[i+2];
}
//PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
lastClkBit = firstFullWave; //set start of wave as clock align
//PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit);
waveStart = 0;
- errCnt=0;
size_t numBits=0;
//set skipped bits
- memset(dest,curPhase^1,firstFullWave / *clock);
+ memset(dest, curPhase^1, firstFullWave / *clock);
numBits += (firstFullWave / *clock);
dest[numBits++] = curPhase; //set first read bit
- for (i = firstFullWave+fullWaveLen-1; i < *size-3; i++){
+ for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
//top edge of wave = start of new wave
if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
if (waveStart == 0) {
waveStart = i+1;
- waveLenCnt=0;
+ waveLenCnt = 0;
avgWaveVal = dest[i+1];
} else { //waveEnd
waveEnd = i+1;
lastAvgWaveVal = avgWaveVal/waveLenCnt;
if (waveLenCnt > fc){
//PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
- //if this wave is a phase shift
+ //this wave is a phase shift
//PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit
- curPhase^=1;
+ curPhase ^= 1;
dest[numBits++] = curPhase;
lastClkBit += *clock;
- } else if (i<lastClkBit+10+fc){
+ } else if (i < lastClkBit+10+fc){
//noise after a phase shift - ignore
} else { //phase shift before supposed to based on clock
errCnt++;
- dest[numBits++] = 77;
+ dest[numBits++] = 7;
}
} else if (i+1 > lastClkBit + *clock + tol + fc){
lastClkBit += *clock; //no phase shift but clock bit
dest[numBits++] = curPhase;
}
- avgWaveVal=0;
- waveStart=i+1;
+ avgWaveVal = 0;
+ waveStart = i+1;
}
}
- avgWaveVal+=dest[i+1];
+ avgWaveVal += dest[i+1];
}
*size = numBits;
return errCnt;
projects / proxmark3-svn / blobdiff