LED_A_OFF();
}
+//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
size_t fsk_demod(uint8_t * dest, size_t size)
{
uint32_t last_transition = 0;
uint32_t idx = 1;
-
- // 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
- uint8_t threshold_value = 127;
+ 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
+ // 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]
+ if (size<100) return size;
+ for(idx=1; idx<100; idx++){
+ if(maxVal<dest[idx]) maxVal = dest[idx];
+ }
+ // 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;
// sync to first lo-hi transition, and threshold
return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0
}
+uint32_t myround(float f)
+{
+ if (f >= 2000) return 2000;//something bad happened
+ return (uint32_t) (f + (float)0.5);
+}
-size_t aggregate_bits(uint8_t *dest,size_t size, uint8_t h2l_crossing_value,uint8_t l2h_crossing_value, uint8_t maxConsequtiveBits, uint8_t invert )
+//translate 11111100000 to 10
+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;
continue;
}
//if lastval was 1, we have a 1->0 crossing
- if ( dest[idx-1] ) {
- n=(n+1) / h2l_crossing_value;
+ if ( dest[idx-1]==1 ) {
+ n=myround((float)(n+1)/((float)(rfLen)/(float)8));
+ //n=(n+1) / h2l_crossing_value;
} else {// 0->1 crossing
- n=(n+1) / l2h_crossing_value;
+ n=myround((float)(n+1)/((float)(rfLen-2)/(float)10));
+ //n=(n+1) / l2h_crossing_value;
}
if (n == 0) n = 1;
return numBits;
}
-// loop to capture raw HID waveform then FSK demodulate the TAG ID from it
+// loop to get raw HID waveform then FSK demodulate the TAG ID from it
void CmdHIDdemodFSK(int findone, int *high, int *low, int ledcontrol)
{
uint8_t *dest = get_bigbufptr_recvrespbuf();
// 1->0 : fc/8 in sets of 6 (RF/50 / 8 = 6.25)
// 0->1 : fc/10 in sets of 5 (RF/50 / 10= 5)
// do not invert
- size = aggregate_bits(dest,size, 6,5,5,0);
+ size = aggregate_bits(dest,size, 50,5,0); //6,5,5,0
WDT_HIT();
uint8_t frame_marker_mask[] = {1,1,1,0,0,0};
int numshifts = 0;
idx = 0;
+ //one scan
+ uint8_t sameCardCount =0;
while( idx + sizeof(frame_marker_mask) < size) {
// search for a start of frame marker
+ if (sameCardCount>2) break; //only up to 2 valid sets of data for the same read of looping card data
if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
{ // frame marker found
idx+=sizeof(frame_marker_mask);
(unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF,
(unsigned int) bitlen, (unsigned int) fc, (unsigned int) cardnum);
}
+ sameCardCount++;
if (findone){
if (ledcontrol) LED_A_OFF();
return;
DoAcquisition125k_internal(-1,true);
size = sizeof(BigBuf);
-
+ //make sure buffer has data
+ if (size < 64) return;
+ //test samples are not just noise
+ uint8_t testMax=0;
+ for(idx=0;idx<64;idx++){
+ if (testMax<dest[idx]) testMax=dest[idx];
+ }
+ idx=0;
+ //if not just noise
+ if (testMax>170){
+ //Dbprintf("testMax: %d",testMax);
// FSK demodulator
size = fsk_demod(dest, size);
// we now have a set of cycle counts, loop over previous results and aggregate data into bit patterns
// 1->0 : fc/8 in sets of 7 (RF/64 / 8 = 8)
// 0->1 : fc/10 in sets of 6 (RF/64 / 10 = 6.4)
- size = aggregate_bits(dest, size, 7,6,13,1); //13 max Consecutive should be ok as most 0s in row should be 10 for init seq - invert bits
-
+ size = aggregate_bits(dest, size, 64, 13, 1); //13 max Consecutive should be ok as most 0s in row should be 10 for init seq - invert bits
+ WDT_HIT();
//Index map
//0 10 20 30 40 50 60
//| | | | | | |
//
//XSF(version)facility:codeone+codetwo
//Handle the data
-
+ uint8_t sameCardCount=0;
uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1};
-
- for( idx=0; idx < (size - 64); idx++) {
+ for( idx=0; idx < (size - 74); idx++) {
+ if (sameCardCount>2) break;
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
if(findone){ //only print binary if we are doing one
Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx], dest[idx+1], dest[idx+2],dest[idx+3],dest[idx+4],dest[idx+5],dest[idx+6],dest[idx+7],dest[idx+8]);
Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx+9], dest[idx+10],dest[idx+11],dest[idx+12],dest[idx+13],dest[idx+14],dest[idx+15],dest[idx+16],dest[idx+17]);
}
code = bytebits_to_byte(dest+idx,32);
code2 = bytebits_to_byte(dest+idx+32,32);
- short version = bytebits_to_byte(dest+idx+28,8); //14,4
- char facilitycode = bytebits_to_byte(dest+idx+19,8) ;
- uint16_t number = (bytebits_to_byte(dest+idx+37,8)<<8)|(bytebits_to_byte(dest+idx+46,8)); //36,9
+ short version = bytebits_to_byte(dest+idx+27,8); //14,4
+ uint8_t facilitycode = bytebits_to_byte(dest+idx+19,8) ;
+ uint16_t number = (bytebits_to_byte(dest+idx+36,8)<<8)|(bytebits_to_byte(dest+idx+45,8)); //36,9
Dbprintf("XSF(%02d)%02x:%d (%08x%08x)",version,facilitycode,number,code,code2);
if (ledcontrol) LED_A_OFF();
isFinish = 1;
break;
+ }
+ sameCardCount++;
+ }
}
}
}
dest[i] = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
++i;
LED_D_OFF();
- if (i > bufferlength) break;
+ if (i >= bufferlength) break;
}
}