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
+ uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
if (*clk <= 32) tol = 1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
size_t MaxBits = 3072; //max bits to collect
lastBit = start - *clk;
// 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 DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low, int *clock) {
uint8_t fndClk[] = {8,16,32,40,50,64,128};
size_t startwave;
size_t i = 100;
size_t minClk = 255;
+ int shortestWaveIdx = 0;
// get to first full low to prime loop and skip incomplete first pulse
while ((dest[i] < high) && (i < size))
++i;
// measure from low to low
while ((dest[i] > low) && (i < size))
++i;
- startwave= 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)
+ if (i-startwave < minClk && i < size) {
minClk = i - startwave;
+ shortestWaveIdx = startwave;
+ }
}
// set clock
if (g_debugMode==2) prnt("DEBUG ASK: detectstrongASKclk smallest wave: %d",minClk);
for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
- if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1)
- return fndClk[clkCnt];
+ if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) {
+ *clock = fndClk[clkCnt];
+ return shortestWaveIdx;
+ }
}
return 0;
}
//test for large clean peaks
if (!clockFnd){
if (DetectCleanAskWave(dest, size, peak, low)==1){
- int ans = DetectStrongAskClock(dest, size, peak, low);
- if (g_debugMode==2) prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %d",ans);
- for (i=clkEnd-1; i>0; i--){
- if (clk[i] == ans) {
- *clock = ans;
- //clockFnd = i;
- return 0; // for strong waves i don't use the 'best start position' yet...
- //break; //clock found but continue to find best startpos [not yet]
- }
+ int ans = DetectStrongAskClock(dest, size, peak, low, clock);
+ if (g_debugMode==2) prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %i, ShortestWave: %i",clock, ans);
+ if (ans > 0) {
+ return ans; //return shortest wave start position
}
}
}
return bestStart[best];
}
+
+int DetectPSKClock(uint8_t dest[], size_t size, int clock) {
+ int firstPhaseShift = 0;
+ return DetectPSKClock_ext(dest, size, clock, &firstPhaseShift);
+}
+
//by marshmellow
//detect psk clock by reading each phase shift
// a phase shift is determined by measuring the sample length of each wave
-int DetectPSKClock(uint8_t dest[], size_t size, int clock)
-{
+int DetectPSKClock_ext(uint8_t dest[], size_t size, int clock, int *firstPhaseShift) {
uint8_t clk[]={255,16,32,40,50,64,100,128,255}; //255 is not a valid clock
uint16_t loopCnt = 4096; //don't need to loop through entire array...
if (size == 0) return 0;
}
}
}
+ *firstPhaseShift = firstFullWave;
if (g_debugMode ==2) prnt("DEBUG PSK: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
-
//test each valid clock from greatest to smallest to see which lines up
for(clkCnt=7; clkCnt >= 1 ; clkCnt--){
lastClkBit = firstFullWave; //set end of wave as clock align
return lowestTransition;
}
+int DetectNRZClock(uint8_t dest[], size_t size, int clock) {
+ size_t bestStart=0;
+ return DetectNRZClock_ext(dest, size, clock, &bestStart);
+}
+
+
//by marshmellow
//detect nrz clock by reading #peaks vs no peaks(or errors)
-int DetectNRZClock(uint8_t dest[], size_t size, int clock)
-{
+int DetectNRZClock_ext(uint8_t dest[], size_t size, int clock, size_t *clockStartIdx) {
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...
uint8_t ignoreWindow = 4;
bool lastPeakHigh = 0;
int lastBit = 0;
+ size_t bestStart[]={0,0,0,0,0,0,0,0,0};
peakcnt=0;
//test each valid clock from smallest to greatest to see which lines up
for(clkCnt=0; clkCnt < 8; ++clkCnt){
}
}
if(peakcnt>peaksdet[clkCnt]) {
+ bestStart[clkCnt]=ii;
peaksdet[clkCnt]=peakcnt;
}
}
}
if (g_debugMode==2) prnt("DEBUG NRZ: Clk: %d, peaks: %d, maxPeak: %d, bestClk: %d, lowestTrs: %d",clk[iii],peaksdet[iii],maxPeak, clk[best], lowestTransition);
}
-
+ *clockStartIdx = bestStart[best];
return clk[best];
}
return 0;
}
+uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) {
+ int firstClockEdge = 0;
+ return detectFSKClk_ext(BitStream, size, fcHigh, fcLow, &firstClockEdge);
+}
+
//by marshmellow
//detects the bit clock for FSK given the high and low Field Clocks
-uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow)
-{
+uint8_t detectFSKClk_ext(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow, int *firstClockEdge) {
uint8_t clk[] = {8,16,32,40,50,64,100,128,0};
uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
rfLens[rfLensFnd++] = rfCounter;
}
} else {
+ *firstClockEdge = i;
firstBitFnd++;
}
rfCounter=0;
*size = newloc;
return true;
}
+
+// by iceman
+// find Visa2000 preamble in already demoded data
+int Visa2kDemod_AM(uint8_t *dest, size_t *size) {
+ if (*size < 96) return -1; //make sure buffer has data
+ size_t startIdx = 0;
+ uint8_t preamble[] = {0,1,0,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0};
+ if (preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx) == 0)
+ return -2; //preamble not found
+ if (*size != 96) return -3; //wrong demoded size
+ //return start position
+ return (int)startIdx;
+}
projects / proxmark3-svn / blobdiff