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LF Demod bug fixes and add lf em em410xdemod

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fixed a few bugs in lf demod that the streamlining added.  added new lf
em em410xdemod command that loops until button pressed. (similar to lf
hid fskdemod
This commit is contained in:
marshmellow42 2014-12-29 15:32:53 -05:00
commit 66707a3b3c
10 changed files with 105 additions and 365 deletions
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62
common/lfdemod.c
View file

@ -27,7 +27,7 @@
//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,uint32_t 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
@ -36,10 +36,10 @@ uint64_t Em410xDecode(uint8_t BitStream[],uint32_t BitLen)
uint64_t lo=0; //hi=0,
uint32_t i = 0;
uint32_t initLoopMax = 1000;
uint32_t initLoopMax = 65;
if (initLoopMax>BitLen) initLoopMax=BitLen;
for (;i < initLoopMax; ++i) //1000 samples should be plenty to find high and low values
for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values
{
if (BitStream[i] > high)
high = BitStream[i];
@ -57,7 +57,7 @@ uint64_t Em410xDecode(uint8_t BitStream[],uint32_t BitLen)
uint32_t ii=0;
uint8_t resetCnt = 0;
while( (idx + 64) < BitLen) {
restart:
restart:
// search for a start of frame marker
if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
{ // frame marker found
@ -101,17 +101,17 @@ int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert)
//int invert=0; //invert default
int high = 0, low = 0;
*clk=DetectClock2(BinStream,(size_t)*BitLen,*clk); //clock default
uint8_t BitStream[MAX_BitStream_LEN] = {0};
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 = 1000;
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) //1000 samples should be plenty to find high and low values
for (i = 0; i < initLoopMax; ++i) //200 samples should be enough to find high and low values
{
if (BinStream[i] > high)
high = BinStream[i];
@ -142,6 +142,7 @@ int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert)
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))){
@ -176,6 +177,7 @@ int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert)
}
}
}
if (bitnum >250) break;
}
//we got more than 64 good bits and not all errors
if ((bitnum > (64+errCnt)) && (errCnt<(*BitLen/1000))) {
@ -220,7 +222,7 @@ int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert)
//run through 2 times and take least errCnt
int manrawdemod(uint8_t * BitStream, int *bitLen)
{
uint8_t BitStream2[MAX_BitStream_LEN]={0};
uint8_t BitStream2[252]={0};
int bitnum=0;
int errCnt =0;
int i=1;
@ -239,6 +241,7 @@ int manrawdemod(uint8_t * BitStream, int *bitLen)
BitStream2[bitnum++]=77;
errCnt++;
}
if(bitnum>250) break;
}
if (bestErr>errCnt){
bestErr=errCnt;
@ -275,15 +278,15 @@ int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
// int invert=0; //invert default
int high = 0, low = 0;
*clk=DetectClock2(BinStream,*bitLen,*clk); //clock default
uint8_t BitStream[MAX_BitStream_LEN] = {0};
uint8_t BitStream[252] = {0};
if (*clk<8) *clk =64;
if (*clk<32) *clk=32;
if (*invert != 0 && *invert != 1) *invert =0;
uint32_t initLoopMax = 1000;
uint32_t initLoopMax = 200;
if (initLoopMax>*bitLen) initLoopMax=*bitLen;
// Detect high and lows
for (i = 0; i < initLoopMax; ++i) //1000 samples should be plenty to find high and low values
for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values
{
if (BinStream[i] > high)
high = BinStream[i];
@ -294,7 +297,7 @@ int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
// PrintAndLog("no data found");
return -1;
}
//13% fuzz in case highs and lows aren't clipped [marshmellow]
//25% fuzz in case highs and lows aren't clipped [marshmellow]
high=(int)(0.75*high);
low=(int)(0.75*low);
@ -363,8 +366,9 @@ int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
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))) {
@ -407,15 +411,13 @@ int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert)
return errCnt;
}
//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
size_t fsk_wave_demod2(uint8_t * dest, size_t size)
size_t fsk_wave_demod(uint8_t * dest, size_t size)
{
uint32_t last_transition = 0;
uint32_t idx = 1;
uint32_t maxVal=0;
// // we don't care about actual value, only if it's more or less than a
// // threshold essentially we capture zero crossings for later analysis
// we do care about the actual value as sometimes near the center of the
// 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]
@ -426,8 +428,8 @@ size_t fsk_wave_demod2(uint8_t * dest, size_t size)
// 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)
uint32_t threshold_value = (uint32_t)(maxVal*.87); idx=1;
//uint8_t threshold_value = 127;
uint8_t threshold_value = (uint8_t)(maxVal*.87); idx=1;
//uint8_t threshold_value = 127;
// sync to first lo-hi transition, and threshold
@ -446,11 +448,11 @@ size_t fsk_wave_demod2(uint8_t * dest, size_t size)
// Check for 0->1 transition
if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition
if (idx-last_transition<6){
if (idx-last_transition<6){ //0-5 = garbage noise
//do nothing with extra garbage
} else if (idx-last_transition < 9) {
} else if (idx-last_transition < 9) { //6-8 = 8 waves
dest[numBits]=1;
} else {
} else { //9+ = 10 waves
dest[numBits]=0;
}
last_transition = idx;
@ -467,7 +469,7 @@ uint32_t myround2(float f)
}
//translate 11111100000 to 10
size_t aggregate_bits2(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,
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,
{
uint8_t lastval=dest[0];
uint32_t idx=0;
@ -485,7 +487,7 @@ size_t aggregate_bits2(uint8_t *dest,size_t size, uint8_t rfLen, uint8_t maxCon
n=myround2((float)(n+1)/((float)(rfLen)/(float)8));
//n=(n+1) / h2l_crossing_value;
} else {// 0->1 crossing
n=myround2((float)(n+1)/((float)(rfLen-2)/(float)10));
n=myround2((float)(n+1)/((float)(rfLen-2)/(float)10)); //-2 for fudge factor
//n=(n+1) / l2h_crossing_value;
}
if (n == 0) n = 1;
@ -518,8 +520,8 @@ int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert)
// }
// size_t size = GraphTraceLen;
// FSK demodulator
size = fsk_wave_demod2(dest, size);
size = aggregate_bits2(dest, size,rfLen,192,invert);
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();
@ -590,7 +592,7 @@ uint32_t bytebits_to_byte(uint8_t* src, int numbits)
int IOdemodFSK(uint8_t *dest, size_t size)
{
size_t idx=0;
uint32_t idx=0;
//make sure buffer has data
if (size < 64) return -1;
//test samples are not just noise
@ -612,14 +614,14 @@ int IOdemodFSK(uint8_t *dest, size_t size)
//
//XSF(version)facility:codeone+codetwo
//Handle the data
uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1};
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 idx;
return (int) idx;
}
}
}

2
common/lfdemod.h
View file

@ -13,7 +13,7 @@
int DetectClock2(uint8_t dest[], size_t size, int clock);
int askmandemod(uint8_t *BinStream,uint32_t *BitLen,int *clk, int *invert);
uint64_t Em410xDecode(uint8_t BitStream[],uint32_t BitLen);
uint64_t Em410xDecode(uint8_t *BitStream,uint32_t BitLen);
int manrawdemod(uint8_t *BitStream, int *bitLen);
int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert);
int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_t *lo);