- // sync to first lo-hi transition
- for( idx=1; idx<m; idx++) {
- if (dest[idx-1]<dest[idx])
- lastval=idx;
- break;
- }
- WDT_HIT();
-
- // 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 with anywhere
- // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
- for( i=0; idx<m; idx++) {
- if (dest[idx-1]<dest[idx]) {
- dest[i]=idx-lastval;
- if (dest[i] <= 8) {
- dest[i]=1;
- } else {
- dest[i]=0;
- }
-
- lastval=idx;
- i++;
- }
- }
- m=i;
- WDT_HIT();
-
- // we now have a set of cycle counts, loop over previous results and aggregate data into bit patterns
- lastval=dest[0];
- idx=0;
- i=0;
- n=0;
- for( idx=0; idx<m; idx++) {
- if (dest[idx]==lastval) {
- n++;
- } else {
- // a bit time is five fc/10 or six fc/8 cycles so figure out how many bits a pattern width represents,
- // an extra fc/8 pattern preceeds every 4 bits (about 200 cycles) just to complicate things but it gets
- // swallowed up by rounding
- // expected results are 1 or 2 bits, any more and it's an invalid manchester encoding
- // special start of frame markers use invalid manchester states (no transitions) by using sequences
- // like 111000
- if (dest[idx-1]) {
- n=(n+1)/6; // fc/8 in sets of 6
- } else {
- n=(n+1)/5; // fc/10 in sets of 5
- }
- switch (n) { // stuff appropriate bits in buffer
- case 0:
- case 1: // one bit
- dest[i++]=dest[idx-1];
- break;
- case 2: // two bits
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- break;
- case 3: // 3 bit start of frame markers
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- break;
- // When a logic 0 is immediately followed by the start of the next transmisson
- // (special pattern) a pattern of 4 bit duration lengths is created.
- case 4:
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- dest[i++]=dest[idx-1];
- break;
- default: // this shouldn't happen, don't stuff any bits
- break;
- }
- n=0;
- lastval=dest[idx];
- }
- }
- m=i;
- WDT_HIT();
-
- // final loop, go over previously decoded manchester data and decode into usable tag ID
- // 111000 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0
- for( idx=0; idx<m-6; idx++) {
- // search for a start of frame marker
- if ( dest[idx] && dest[idx+1] && dest[idx+2] && (!dest[idx+3]) && (!dest[idx+4]) && (!dest[idx+5]) )
- {
- found=1;
- idx+=6;
- if (found && (hi2|hi|lo)) {
- if (hi2 != 0){
- Dbprintf("TAG ID: %x%08x%08x (%d)",
- (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
- }
- else {
- Dbprintf("TAG ID: %x%08x (%d)",
- (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
- }
- /* if we're only looking for one tag */
- if (findone)
- {
- *high = hi;
- *low = lo;
- return;
- }
- hi2=0;
- hi=0;
- lo=0;
- found=0;
- }
- }
- if (found) {
- if (dest[idx] && (!dest[idx+1]) ) {
- hi2=(hi2<<1)|(hi>>31);
- hi=(hi<<1)|(lo>>31);
- lo=(lo<<1)|0;
- } else if ( (!dest[idx]) && dest[idx+1]) {
- hi2=(hi2<<1)|(hi>>31);
- hi=(hi<<1)|(lo>>31);
- lo=(lo<<1)|1;
- } else {
- found=0;
- hi2=0;
- hi=0;
- lo=0;
- }
- idx++;
- }
- if ( dest[idx] && dest[idx+1] && dest[idx+2] && (!dest[idx+3]) && (!dest[idx+4]) && (!dest[idx+5]) )
- {
- found=1;
- idx+=6;
- if (found && (hi|lo)) {
- if (hi2 != 0){
- Dbprintf("TAG ID: %x%08x%08x (%d)",
- (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
- }
- else {
- Dbprintf("TAG ID: %x%08x (%d)",
- (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
- }
- /* if we're only looking for one tag */
- if (findone)
- {
- *high = hi;
- *low = lo;
- return;
- }
- hi2=0;
- hi=0;
- lo=0;
- found=0;
- }
- }
- }
- WDT_HIT();
- }
+void CmdIOdemodFSK(int findone, int *high, int *low, int ledcontrol)
+{
+ uint8_t *dest = BigBuf_get_addr();
+ int idx=0;
+ uint32_t code=0, code2=0;
+ uint8_t version=0;
+ uint8_t facilitycode=0;
+ uint16_t number=0;
+ // Configure to go in 125Khz listen mode
+ LFSetupFPGAForADC(95, true);
+
+ while(!BUTTON_PRESS()) {
+ WDT_HIT();
+ if (ledcontrol) LED_A_ON();
+ DoAcquisition_default(-1,true);
+ //fskdemod and get start index
+ WDT_HIT();
+ idx = IOdemodFSK(dest, BigBuf_max_traceLen());
+ if (idx>0){
+ //valid tag found
+
+ //Index map
+ //0 10 20 30 40 50 60
+ //| | | | | | |
+ //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
+ //
+ //XSF(version)facility:codeone+codetwo
+ //Handle the data
+ 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]);
+ Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx+18],dest[idx+19],dest[idx+20],dest[idx+21],dest[idx+22],dest[idx+23],dest[idx+24],dest[idx+25],dest[idx+26]);
+ Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx+27],dest[idx+28],dest[idx+29],dest[idx+30],dest[idx+31],dest[idx+32],dest[idx+33],dest[idx+34],dest[idx+35]);
+ Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx+36],dest[idx+37],dest[idx+38],dest[idx+39],dest[idx+40],dest[idx+41],dest[idx+42],dest[idx+43],dest[idx+44]);
+ Dbprintf("%d%d%d%d%d%d%d%d %d",dest[idx+45],dest[idx+46],dest[idx+47],dest[idx+48],dest[idx+49],dest[idx+50],dest[idx+51],dest[idx+52],dest[idx+53]);
+ Dbprintf("%d%d%d%d%d%d%d%d %d%d",dest[idx+54],dest[idx+55],dest[idx+56],dest[idx+57],dest[idx+58],dest[idx+59],dest[idx+60],dest[idx+61],dest[idx+62],dest[idx+63]);
+ }
+ code = bytebits_to_byte(dest+idx,32);
+ code2 = bytebits_to_byte(dest+idx+32,32);
+ version = bytebits_to_byte(dest+idx+27,8); //14,4
+ facilitycode = bytebits_to_byte(dest+idx+18,8) ;
+ number = (bytebits_to_byte(dest+idx+36,8)<<8)|(bytebits_to_byte(dest+idx+45,8)); //36,9
+
+ Dbprintf("XSF(%02d)%02x:%05d (%08x%08x)",version,facilitycode,number,code,code2);
+ // if we're only looking for one tag
+ if (findone){
+ if (ledcontrol) LED_A_OFF();
+ //LED_A_OFF();
+ *high=code;
+ *low=code2;
+ return;
+ }
+ code=code2=0;
+ version=facilitycode=0;
+ number=0;
+ idx=0;
+ }
+ WDT_HIT();
+ }
+ DbpString("Stopped");
+ if (ledcontrol) LED_A_OFF();