//-----------------------------------------------------------------------------
// Low frequency demod/decode commands
//-----------------------------------------------------------------------------
-
-#include <stdlib.h>
#include "lfdemod.h"
-#include <string.h>
//un_comment to allow debug print calls when used not on device
void dummy(char *fmt, ...){}
+
#ifndef ON_DEVICE
-#include "ui.h"
-#include "cmdparser.h"
-#include "cmddata.h"
-#define prnt PrintAndLog
+# include "ui.h"
+# include "cmdparser.h"
+# include "cmddata.h"
+# define prnt PrintAndLog
#else
uint8_t g_debugMode=0;
-#define prnt dummy
+# define prnt dummy
#endif
//test samples are not just noise
for (uint8_t i = 0; i < bitLen; i++){
ans ^= ((bits >> i) & 1);
}
- //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
+ if (g_debugMode) prnt("DEBUG: ans: %d, ptype: %d, bits: %08X",ans,pType,bits);
return (ans == pType);
}
parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
BitStream[j++] = (BitStream[startIdx+word+bit]);
}
+ if (word+pLen >= bLen) break;
+
j--; // overwrite parity with next data
// if parity fails then return 0
switch (pType) {
smplCnt++;
} else { //transition
if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
+
if (smplCnt > clk-(clk/4)-1) { //full clock
if (smplCnt > clk + (clk/4)+1) { //too many samples
errCnt++;
if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i);
- BinStream[bitCnt++]=7;
+ BinStream[bitCnt++] = 7;
} else if (waveHigh) {
BinStream[bitCnt++] = invert;
BinStream[bitCnt++] = invert;
{
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);
- if (g_debugMode==2) prnt("DEBUG ASK: clk %d, beststart %d", *clk, start);
+ if (g_debugMode==2) prnt("DEBUG ASK: clk %d, beststart %d, amp %d", *clk, start, amp);
uint8_t initLoopMax = 255;
if (initLoopMax > *size) initLoopMax = *size;
errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low);
if (askType) //askman
return manrawdecode(BinStream, size, 0);
- else //askraw
- return errCnt;
+ //askraw
+ return errCnt;
}
if (g_debugMode==2) prnt("DEBUG ASK: Weak Wave Detected - using weak wave demod");
*size = bitnum;
return errCnt;
}
-
//by marshmellow
//take 10 and 01 and manchester decode
//run through 2 times and take least errCnt
-int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert)
-{
- uint16_t bitnum=0, MaxBits = 512, errCnt = 0;
- size_t i, ii;
- uint16_t bestErr = 1000, bestRun = 0;
+int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert){
+ int errCnt = 0, bestErr = 1000;
+ uint16_t bitnum = 0, MaxBits = 512, bestRun = 0;
+ size_t i, k;
if (*size < 16) return -1;
//find correct start position [alignment]
- for (ii=0;ii<2;++ii){
- for (i=ii; i<*size-3; i+=2)
- if (BitStream[i]==BitStream[i+1])
+ for (k=0; k < 2; ++k){
+ for (i=k; i<*size-3; i += 2)
+ if (BitStream[i] == BitStream[i+1])
errCnt++;
- if (bestErr>errCnt){
- bestErr=errCnt;
- bestRun=ii;
+ if (bestErr > errCnt){
+ bestErr = errCnt;
+ bestRun = k;
}
errCnt=0;
}
//decode
- for (i=bestRun; i < *size-3; i+=2){
- if(BitStream[i] == 1 && (BitStream[i+1] == 0)){
- BitStream[bitnum++]=invert;
- } else if((BitStream[i] == 0) && BitStream[i+1] == 1){
- BitStream[bitnum++]=invert^1;
+ 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;
+ BitStream[bitnum++] = 7;
}
- if(bitnum>MaxBits) break;
+ if (bitnum>MaxBits) break;
}
*size=bitnum;
return bestErr;
size_t preLastSample = 0;
size_t LastSample = 0;
size_t currSample = 0;
- // sync to first lo-hi transition, and threshold
+ if ( size < 1024 ) return 0; // not enough samples
+
+ // jump to modulating data by finding the first 4 threshold crossings (or first 2 waves)
+ // in case you have junk or noise at the beginning of the trace...
+ uint8_t thresholdCnt = 0;
+ size_t waveSizeCnt = 0;
+ bool isAboveThreshold = dest[idx++] >= threshold_value;
+ for (; idx < size-20; idx++ ) {
+ if(dest[idx] < threshold_value && isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < fchigh+1) break;
+ isAboveThreshold = false;
+ waveSizeCnt = 0;
+ } else if (dest[idx] >= threshold_value && !isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < fchigh+1) break;
+ isAboveThreshold = true;
+ waveSizeCnt = 0;
+ } else {
+ waveSizeCnt++;
+ }
+ if (thresholdCnt > 10) break;
+ }
+ if (g_debugMode == 2) prnt("threshold Count reached at %u",idx);
// Need to threshold first sample
- // skip 160 samples to allow antenna/samples to settle
- if(dest[160] < threshold_value) dest[0] = 0;
+ if(dest[idx] < threshold_value) dest[0] = 0;
else dest[0] = 1;
+ idx++;
size_t numBits = 0;
// count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
// or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere
// between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
// (could also be fc/5 && fc/7 for fsk1 = 4-9)
- for(idx = 161; idx < size-20; idx++) {
+ for(; idx < size-20; idx++) {
// threshold current value
if (dest[idx] < threshold_value) dest[idx] = 0;
//do nothing with extra garbage
} else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves (or 3-6 = 5)
//correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5)
- if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1) || preLastSample == 0 )){
+ if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1))){
dest[numBits-1]=1;
}
dest[numBits++]=1;
- } else if (currSample > (fchigh) && !numBits) { //12 + and first bit = unusable garbage
- //do nothing with beginning garbage
+ } else if (currSample > (fchigh+1) && numBits < 3) { //12 + and first two bit = unusable garbage
+ //do nothing with beginning garbage and reset.. should be rare..
+ numBits = 0;
} else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's (or 4 then a 6 should be two 5's)
dest[numBits++]=1;
} else { //9+ = 10 sample waves (or 6+ = 7)
uint32_t n=1;
for( idx=1; idx < size; idx++) {
n++;
- if (dest[idx]==lastval) continue;
+ if (dest[idx]==lastval) continue; //skip until we hit a transition
//find out how many bits (n) we collected
//if lastval was 1, we have a 1->0 crossing
*hi2 = (*hi2<<1)|(*hi>>31);
*hi = (*hi<<1)|(*lo>>31);
//Then, shift in a 0 or one into low
+ *lo <<= 1;
if (dest[idx] && !dest[idx+1]) // 1 0
- *lo=(*lo<<1)|1;
+ *lo |= 1;
else // 0 1
- *lo=(*lo<<1)|0;
+ *lo |= 0;
}
return (int)startIdx;
}
int VikingDemod_AM(uint8_t *dest, size_t *size) {
//make sure buffer has data
if (*size < 64*2) return -2;
-
size_t startIdx = 0;
uint8_t preamble[] = {1,1,1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
if ( checkCalc != 0xA8 ) return -5;
if (*size != 64) return -6;
//return start position
- return (int) startIdx;
+ return (int)startIdx;
}
// by iceman
// find Visa2000 preamble in already demoded data
int Visa2kDemod_AM(uint8_t *dest, size_t *size) {
- if (*size < 96*2) return -1; //make sure buffer has data
+ if (*size < 96) return -1; //make sure buffer has data
size_t startIdx = 0;
uint8_t preamble[] = {0,1,0,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0};
uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
if (errChk == 0) return -2; //preamble not found
if (*size != 96) return -3; //wrong demoded size
//return start position
- return (int) startIdx;
+ return (int)startIdx;
}
// by iceman
// find Noralsy preamble in already demoded data
int NoralsyDemod_AM(uint8_t *dest, size_t *size) {
- if (*size < 96*2) return -1; //make sure buffer has data
+ if (*size < 96) return -1; //make sure buffer has data
size_t startIdx = 0;
uint8_t preamble[] = {1,0,1,1,1,0,1,1,0,0,0,0};
uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
if (errChk == 0) return -2; //preamble not found
if (*size != 96) return -3; //wrong demoded size
//return start position
- return (int) startIdx;
+ return (int)startIdx;
}
// find presco preamble 0x10D in already demoded data
int PrescoDemod(uint8_t *dest, size_t *size) {
if (errChk == 0) return -2; //preamble not found
if (*size != 128) return -3; //wrong demoded size
//return start position
- return (int) startIdx;
+ return (int)startIdx;
}
// Ask/Biphase Demod then try to locate an ISO 11784/85 ID
// BitStream must contain previously askrawdemod and biphasedemoded data
-int FDXBdemodBI(uint8_t *dest, size_t *size)
-{
- //make sure buffer has enough data
- if (*size < 128) return -1;
-
+int FDXBdemodBI(uint8_t *dest, size_t *size) {
+ if (*size < 128*2) return -1; //make sure buffer has enough data
size_t startIdx = 0;
uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1};
-
uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
if (errChk == 0) return -2; //preamble not found
+ if (*size != 128) return -3; //wrong demoded size
+ //return start position
return (int)startIdx;
}
// ASK/Diphase fc/64 (inverted Biphase)
// Note: this i s not a demod, this is only a detection
// the parameter *dest needs to be demoded before call
+// 0xFFFF preamble, 64bits
int JablotronDemod(uint8_t *dest, size_t *size){
- //make sure buffer has enough data
- if (*size < 64) return -1;
-
+ if (*size < 64*2) return -1; //make sure buffer has enough data
size_t startIdx = 0;
- // 0xFFFF preamble, 64bits
- uint8_t preamble[] = {
- 1,1,1,1,
- 1,1,1,1,
- 1,1,1,1,
- 1,1,1,1,
- 0
- };
-
+ uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -4; //preamble not found
- if (*size != 64) return -3;
+ if (errChk == 0) return -2; //preamble not found
+ if (*size != 64) return -3; // wrong demoded size
uint8_t checkchksum = 0;
for (int i=16; i < 56; i += 8) {
checkchksum += bytebits_to_byte(dest+startIdx+i,8);
}
checkchksum ^= 0x3A;
-
uint8_t crc = bytebits_to_byte(dest+startIdx+56, 8);
-
- if ( checkchksum != crc ) return -5;
+ if ( checkchksum != crc ) return -5;
return (int)startIdx;
}
return (int) startIdx;
}
+// Find IDTEC PSK1, RF Preamble == 0x4944544B, Demodsize 64bits
+// by iceman
+int IdteckDemodPSK(uint8_t *dest, size_t *size) {
+ //make sure buffer has data
+ if (*size < 64*2) return -1;
+ size_t startIdx = 0;
+ uint8_t preamble[] = {0,1,0,0,1,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,1,0,1,1};
+ uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
+ if (errChk == 0) return -2; //preamble not found
+ if (*size != 64) return -3; // wrong demoded size
+ return (int) startIdx;
+}
+
// by marshmellow
// to detect a wave that has heavily clipped (clean) samples
uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low)
if (clockFnd>0) {
clkCnt = clockFnd;
clkEnd = clockFnd+1;
+ } else {
+ clkCnt=1;
}
- else clkCnt=1;
//test each valid clock from smallest to greatest to see which lines up
- for(; clkCnt < clkEnd; clkCnt++){
- if (clk[clkCnt] <= 32){
+ for(; clkCnt < clkEnd; clkCnt++) {
+ if (clk[clkCnt] <= 32) {
tol=1;
- }else{
+ } else {
tol=0;
}
//if no errors allowed - keep start within the first clock
- if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) loopCnt=clk[clkCnt]*2;
- bestErr[clkCnt]=1000;
+ if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128)
+ loopCnt = clk[clkCnt] * 2;
+
+ bestErr[clkCnt] = 1000;
+
//try lining up the peaks by moving starting point (try first few clocks)
for (ii=0; ii < loopCnt; ii++){
if (dest[ii] < peak && dest[ii] > low) continue;
- errCnt=0;
+ errCnt = 0;
// now that we have the first one lined up test rest of wave array
loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1;
for (i=0; i < loopEnd; ++i){
}
//if we found no errors then we can stop here and a low clock (common clocks)
// this is correct one - return this clock
- if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d",clk[clkCnt],errCnt,ii,i);
- if(errCnt==0 && clkCnt<7) {
+ if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d", clk[clkCnt], errCnt, ii, i);
+ if (errCnt==0 && clkCnt<7) {
if (!clockFnd) *clock = clk[clkCnt];
return ii;
}
//if we found errors see if it is lowest so far and save it as best run
- if(errCnt<bestErr[clkCnt]){
- bestErr[clkCnt]=errCnt;
- bestStart[clkCnt]=ii;
+ if (errCnt < bestErr[clkCnt]) {
+ bestErr[clkCnt] = errCnt;
+ bestStart[clkCnt] = ii;
}
}
}
- uint8_t iii;
- uint8_t best=0;
- for (iii=1; iii<clkEnd; ++iii){
- if (bestErr[iii] < bestErr[best]){
- if (bestErr[iii] == 0) bestErr[iii]=1;
+ uint8_t k;
+ uint8_t best = 0;
+ for (k=1; k < clkEnd; ++k){
+ if (bestErr[k] < bestErr[best]){
+ if (bestErr[k] == 0) bestErr[k]=1;
// current best bit to error ratio vs new bit to error ratio
- if ( (size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii] ){
- best = iii;
+ if ( (size/clk[best])/bestErr[best] < (size/clk[k])/bestErr[k] ){
+ best = k;
}
}
- if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d",clk[iii],bestErr[iii],clk[best],bestStart[best]);
+ if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]);
}
if (!clockFnd) *clock = clk[best];
return bestStart[best];
// by marshmellow
// convert psk1 demod to psk2 demod
// only transition waves are 1s
-void psk1TOpsk2(uint8_t *BitStream, size_t size)
-{
- size_t i=1;
- uint8_t lastBit=BitStream[0];
- for (; i<size; i++){
- if (BitStream[i]==7){
- //ignore errors
- } else if (lastBit!=BitStream[i]){
- lastBit=BitStream[i];
- BitStream[i]=1;
+void psk1TOpsk2(uint8_t *bits, size_t size) {
+ uint8_t lastBit = bits[0];
+ for (size_t i = 1; i < size; i++){
+ //ignore errors
+ if (bits[i] == 7) continue;
+
+ if (lastBit != bits[i]){
+ lastBit = bits[i];
+ bits[i] = 1;
} else {
- BitStream[i]=0;
+ bits[i] = 0;
}
}
- return;
}
// by marshmellow
// convert psk2 demod to psk1 demod
// from only transition waves are 1s to phase shifts change bit
-void psk2TOpsk1(uint8_t *BitStream, size_t size)
-{
- uint8_t phase=0;
- for (size_t i=0; i<size; i++){
- if (BitStream[i]==1){
- phase ^=1;
+void psk2TOpsk1(uint8_t *bits, size_t size) {
+ uint8_t phase = 0;
+ for (size_t i = 0; i < size; i++){
+ if (bits[i] == 1){
+ phase ^= 1;
}
- BitStream[i]=phase;
+ bits[i] = phase;
}
- return;
}
// redesigned by marshmellow adjusted from existing decode functions
fcCounter=0;
rfCounter=0;
firstBitFnd=0;
- //PrintAndLog("DEBUG: fcTol: %d",fcTol);
+ //prnt("DEBUG: fcTol: %d",fcTol);
// prime i to first peak / up transition
for (i = 160; i < size-20; i++)
if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1])
}
}
if (rfCounter > 0 && rfLensFnd < 15){
- //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
+ //prnt("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
rfCnts[rfLensFnd]++;
rfLens[rfLensFnd++] = rfCounter;
}
uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint8_t fcLensFnd = 0;
- uint8_t lastFCcnt=0;
+ uint8_t lastFCcnt = 0;
uint8_t fcCounter = 0;
size_t i;
- if (size == 0) return 0;
+ if (size < 180) return 0;
// prime i to first up transition
for (i = 160; i < size-20; i++)
size_t numBits=0;
uint8_t curPhase = *invert;
- size_t i, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
+ size_t i=0, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
uint8_t fc=0, fullWaveLen=0, tol=1;
uint16_t errCnt=0, waveLenCnt=0;
fc = countFC(dest, *size, 0);
if (fc!=2 && fc!=4 && fc!=8) return -1;
- //PrintAndLog("DEBUG: FC: %d",fc);
+ //prnt("DEBUG: FC: %d",fc);
*clock = DetectPSKClock(dest, *size, *clock);
if (*clock == 0) return -1;
+ // jump to modulating data by finding the first 2 threshold crossings (or first 1 waves)
+ // in case you have junk or noise at the beginning of the trace...
+ uint8_t thresholdCnt = 0;
+ size_t waveSizeCnt = 0;
+ uint8_t threshold_value = 123; //-5
+ bool isAboveThreshold = dest[i++] >= threshold_value;
+ for (; i < *size-20; i++ ) {
+ if(dest[i] < threshold_value && isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < fc+1) break;
+ isAboveThreshold = false;
+ waveSizeCnt = 0;
+ } else if (dest[i] >= threshold_value && !isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < fc+1) break;
+ isAboveThreshold = true;
+ waveSizeCnt = 0;
+ } else {
+ waveSizeCnt++;
+ }
+ if (thresholdCnt > 10) break;
+ }
+ if (g_debugMode == 2) prnt("DEBUG PSK: threshold Count reached at %u, count: %u",i, thresholdCnt);
+
+
int avgWaveVal=0, lastAvgWaveVal=0;
+ waveStart = i+1;
//find first phase shift
- for (i=0; i<loopCnt; i++){
+ for (; i<loopCnt; i++){
if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
waveEnd = i+1;
- //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+ if (g_debugMode == 2) prnt("DEBUG PSK: waveEnd: %u, waveStart: %u",waveEnd, waveStart);
waveLenCnt = waveEnd-waveStart;
- if (waveLenCnt > fc && waveStart > fc && !(waveLenCnt > fc+2)){ //not first peak and is a large wave but not out of whack
+ if (waveLenCnt > fc && waveStart > fc && !(waveLenCnt > fc+3)){ //not first peak and is a large wave but not out of whack
lastAvgWaveVal = avgWaveVal/(waveLenCnt);
firstFullWave = waveStart;
fullWaveLen=waveLenCnt;
//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 > threshold_value) curPhase ^= 1; //fudge graph 0 a little 123 vs 128
break;
}
waveStart = i+1;
waveLenCnt = waveEnd-waveStart;
lastAvgWaveVal = avgWaveVal/waveLenCnt;
if (waveLenCnt > fc){
- //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
+ //prnt("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
//this wave is a phase shift
- //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
+ //prnt("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit
curPhase ^= 1;
dest[numBits++] = curPhase;
int tol = 0;
int i, j, skip, start, end, low, high, minClk, waveStart;
bool complete = false;
- int tmpbuff[bufsize / 64];
- int waveLen[bufsize / 64];
+ int tmpbuff[bufsize / 32]; //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured
+ int waveLen[bufsize / 32]; // if clock is larger then we waste memory in array size that is not needed...
size_t testsize = (bufsize < 512) ? bufsize : 512;
int phaseoff = 0;
high = low = 128;
memset(tmpbuff, 0, sizeof(tmpbuff));
+ memset(waveLen, 0, sizeof(waveLen));
+
if ( getHiLo(buffer, testsize, &high, &low, 80, 80) == -1 ) {
if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting");
return false; //just noise
waveStart = i;
while ((buffer[i] > low) && (i < bufsize))
++i;
- if (j >= (bufsize/64)) {
+ if (j >= (bufsize/32)) {
break;
}
waveLen[j] = i - waveStart; //first high to first low
if (start < 0) {
if (g_debugMode==2) prnt("DEBUG STT: first STT not found - quitting");
return false;
+ } else {
+ if (g_debugMode==2) prnt("DEBUG STT: first STT found at: %d, j=%d",start, j);
}
if (waveLen[i+2] > clk*1+tol)
phaseoff = 0;
end = skip;
for (i += 3; i < j - 4; ++i) {
end += tmpbuff[i];
- if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol) { //1 to 2 clocks depending on 2 bits prior
+ if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior
if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol && waveLen[i+1] > clk*3/2-tol) { //2 clocks and wave size is 1 1/2
if (tmpbuff[i+2] >= (clk*3)/2-tol && tmpbuff[i+2] <= clk*2+tol && waveLen[i+2] > clk-tol) { //1 1/2 to 2 clocks and at least one full clock wave
if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit
start = skip;
size_t datalen = end - start;
// check validity of datalen (should be even clock increments) - use a tolerance of up to 1/8th a clock
- if (datalen % clk > clk/8) {
+ if ( clk - (datalen % clk) <= clk/8) {
+ // padd the amount off - could be problematic... but shouldn't happen often
+ datalen += clk - (datalen % clk);
+ } else if ( (datalen % clk) <= clk/8 ) {
+ // padd the amount off - could be problematic... but shouldn't happen often
+ datalen -= datalen % clk;
+ } else {
if (g_debugMode==2) prnt("DEBUG STT: datalen not divisible by clk: %u %% %d = %d - quitting", datalen, clk, datalen % clk);
return false;
- } else {
- // padd the amount off - could be problematic... but shouldn't happen often
- datalen += datalen % clk;
}
// if datalen is less than one t55xx block - ERROR
if (datalen/clk < 8*4) {
return false;
}
size_t dataloc = start;
+ if (buffer[dataloc-(clk*4)-(clk/8)] <= low && buffer[dataloc] <= low && buffer[dataloc-(clk*4)] >= high) {
+ //we have low drift (and a low just before the ST and a low just after the ST) - compensate by backing up the start
+ for ( i=0; i <= (clk/8); ++i ) {
+ if ( buffer[dataloc - (clk*4) - i] <= low ) {
+ dataloc -= i;
+ break;
+ }
+ }
+ }
+
size_t newloc = 0;
i=0;
+ if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen);
+
// warning - overwriting buffer given with raw wave data with ST removed...
while ( dataloc < bufsize-(clk/2) ) {
//compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part)
}
newloc += i;
//skip next ST - we just assume it will be there from now on...
+ if (g_debugMode==2) prnt("DEBUG STT: skipping STT at %d to %d", dataloc, dataloc+(clk*4));
dataloc += clk*4;
}
*size = newloc;
projects / proxmark3-svn / blobdiff