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Merge branch 'master' of https://github.com/Proxmark/proxmark3

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iceman1001 2015-01-06 20:51:11 +01:00
commit bf8328e928
1 changed files with 30 additions and 31 deletions
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61
common/lfdemod.c
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@ -592,41 +592,40 @@ uint32_t bytebits_to_byte(uint8_t* src, int numbits)
int IOdemodFSK(uint8_t *dest, size_t size) int IOdemodFSK(uint8_t *dest, size_t size)
{ {
static const uint8_t THRESHOLD = 140;
uint32_t idx=0; uint32_t idx=0;
//make sure buffer has data //make sure buffer has data
if (size < 66) return -1; if (size < 66) return -1;
//test samples are not just noise //test samples are not just noise
uint8_t testMax=0; uint8_t justNoise = 1;
for(idx=0;idx<65;idx++){ for(idx=0;idx< size && justNoise ;idx++){
if (testMax<dest[idx]) testMax=dest[idx]; justNoise = dest[idx] < THRESHOLD;
} }
idx=0; if(justNoise) return 0;
//if not just noise
if (testMax>20){ // FSK demodulator
// FSK demodulator size = fskdemod(dest, size,64,1,10,8); // RF/64 and invert
size = fskdemod(dest, size,64,1,10,8); // RF/64 and invert if (size < 65) return -1; //did we get a good demod?
if (size < 65) return -1; //did we get a good demod? //Index map
//Index map //0 10 20 30 40 50 60
//0 10 20 30 40 50 60 //| | | | | | |
//| | | | | | | //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
//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
//00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11 //
// //XSF(version)facility:codeone+codetwo
//XSF(version)facility:codeone+codetwo //Handle the data
//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 - 65); idx++) {
for( idx=0; idx < (size - 65); idx++) { if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
if ( memcmp(dest + idx, mask, sizeof(mask))==0) { //frame marker found
//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){
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
//confirmed proper separator bits found //return start position
//return start position return (int) idx;
return (int) idx; }
} }
} }
}
}
return 0; return 0;
} }