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cvs.zerfleddert.de Git - proxmark3-svn/blob - common/lfdemod.c
f27ffff35c119f158cad162d89ed60bf6762952f
1 //-----------------------------------------------------------------------------
4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
5 // at your option, any later version. See the LICENSE.txt file for the text of
7 //-----------------------------------------------------------------------------
8 // Low frequency demod/decode commands
9 //-----------------------------------------------------------------------------
15 //un_comment to allow debug print calls when used not on device
16 void dummy ( char * fmt
, ...){}
20 #include "cmdparser.h"
22 #define prnt PrintAndLog
24 uint8_t g_debugMode
= 0 ;
28 uint8_t justNoise ( uint8_t * BitStream
, size_t size
)
30 static const uint8_t THRESHOLD
= 123 ;
31 //test samples are not just noise
32 uint8_t justNoise1
= 1 ;
33 for ( size_t idx
= 0 ; idx
< size
&& justNoise1
; idx
++){
34 justNoise1
= BitStream
[ idx
] < THRESHOLD
;
40 //get high and low values of a wave with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise
41 int getHiLo ( uint8_t * BitStream
, size_t size
, int * high
, int * low
, uint8_t fuzzHi
, uint8_t fuzzLo
)
45 // get high and low thresholds
46 for ( size_t i
= 0 ; i
< size
; i
++){
47 if ( BitStream
[ i
] > * high
) * high
= BitStream
[ i
];
48 if ( BitStream
[ i
] < * low
) * low
= BitStream
[ i
];
50 if (* high
< 123 ) return - 1 ; // just noise
51 * high
= ((* high
- 128 )* fuzzHi
+ 12800 )/ 100 ;
52 * low
= ((* low
- 128 )* fuzzLo
+ 12800 )/ 100 ;
57 // pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType
58 // returns 1 if passed
59 uint8_t parityTest ( uint32_t bits
, uint8_t bitLen
, uint8_t pType
)
62 for ( uint8_t i
= 0 ; i
< bitLen
; i
++){
63 ans
^= (( bits
>> i
) & 1 );
65 //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
66 return ( ans
== pType
);
70 // takes a array of binary values, start position, length of bits per parity (includes parity bit),
71 // Parity Type (1 for odd; 0 for even; 2 for Always 1's; 3 for Always 0's), and binary Length (length to run)
72 size_t removeParity ( uint8_t * BitStream
, size_t startIdx
, uint8_t pLen
, uint8_t pType
, size_t bLen
)
74 uint32_t parityWd
= 0 ;
75 size_t j
= 0 , bitCnt
= 0 ;
76 for ( int word
= 0 ; word
< ( bLen
); word
+= pLen
){
77 for ( int bit
= 0 ; bit
< pLen
; bit
++){
78 parityWd
= ( parityWd
<< 1 ) | BitStream
[ startIdx
+ word
+ bit
];
79 BitStream
[ j
++] = ( BitStream
[ startIdx
+ word
+ bit
]);
81 j
--; // overwrite parity with next data
82 // if parity fails then return 0
84 case 3 : if ( BitStream
[ j
]== 1 ) return 0 ; break ; //should be 0 spacer bit
85 case 2 : if ( BitStream
[ j
]== 0 ) return 0 ; break ; //should be 1 spacer bit
86 default : //test parity
87 if ( parityTest ( parityWd
, pLen
, pType
) == 0 ) return 0 ; break ;
92 // if we got here then all the parities passed
93 //return ID start index and size
98 // takes a array of binary values, length of bits per parity (includes parity bit),
99 // Parity Type (1 for odd; 0 for even; 2 Always 1's; 3 Always 0's), and binary Length (length to run)
100 // Make sure *dest is long enough to store original sourceLen + #_of_parities_to_be_added
101 size_t addParity ( uint8_t * BitSource
, uint8_t * dest
, uint8_t sourceLen
, uint8_t pLen
, uint8_t pType
)
103 uint32_t parityWd
= 0 ;
104 size_t j
= 0 , bitCnt
= 0 ;
105 for ( int word
= 0 ; word
< sourceLen
; word
+= pLen
- 1 ) {
106 for ( int bit
= 0 ; bit
< pLen
- 1 ; bit
++){
107 parityWd
= ( parityWd
<< 1 ) | BitSource
[ word
+ bit
];
108 dest
[ j
++] = ( BitSource
[ word
+ bit
]);
111 // if parity fails then return 0
113 case 3 : dest
[ j
++]= 0 ; break ; // marker bit which should be a 0
114 case 2 : dest
[ j
++]= 1 ; break ; // marker bit which should be a 1
116 dest
[ j
++] = parityTest ( parityWd
, pLen
- 1 , pType
) ^ 1 ;
122 // if we got here then all the parities passed
123 //return ID start index and size
127 uint32_t bytebits_to_byte ( uint8_t * src
, size_t numbits
)
130 for ( int i
= 0 ; i
< numbits
; i
++) {
131 num
= ( num
<< 1 ) | (* src
);
137 //least significant bit first
138 uint32_t bytebits_to_byteLSBF ( uint8_t * src
, size_t numbits
)
141 for ( int i
= 0 ; i
< numbits
; i
++) {
142 num
= ( num
<< 1 ) | *( src
+ ( numbits
-( i
+ 1 )));
148 //search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length
149 uint8_t preambleSearch ( uint8_t * BitStream
, uint8_t * preamble
, size_t pLen
, size_t * size
, size_t * startIdx
)
152 for ( int idx
= 0 ; idx
< * size
- pLen
; idx
++){
153 if ( memcmp ( BitStream
+ idx
, preamble
, pLen
) == 0 ){
160 * size
= idx
- * startIdx
;
169 //takes 1s and 0s and searches for EM410x format - output EM ID
170 uint8_t Em410xDecode ( uint8_t * BitStream
, size_t * size
, size_t * startIdx
, uint32_t * hi
, uint64_t * lo
)
172 //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
173 // otherwise could be a void with no arguments
176 if ( BitStream
[ 1 ]> 1 ) return 0 ; //allow only 1s and 0s
178 // 111111111 bit pattern represent start of frame
179 // include 0 in front to help get start pos
180 uint8_t preamble
[] = { 0 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 };
182 uint32_t parityBits
= 0 ;
186 errChk
= preambleSearch ( BitStream
, preamble
, sizeof ( preamble
), size
, startIdx
);
187 if ( errChk
== 0 || * size
< 64 ) return 0 ;
188 if (* size
> 64 ) FmtLen
= 22 ;
189 * startIdx
+= 1 ; //get rid of 0 from preamble
191 for ( i
= 0 ; i
< FmtLen
; i
++){ //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits)
192 parityBits
= bytebits_to_byte ( BitStream
+( i
* 5 )+ idx
, 5 );
193 //check even parity - quit if failed
194 if ( parityTest ( parityBits
, 5 , 0 ) == 0 ) return 0 ;
195 //set uint64 with ID from BitStream
196 for ( uint8_t ii
= 0 ; ii
< 4 ; ii
++){
197 * hi
= (* hi
<< 1 ) | (* lo
>> 63 );
198 * lo
= (* lo
<< 1 ) | ( BitStream
[( i
* 5 )+ ii
+ idx
]);
201 if ( errChk
!= 0 ) return 1 ;
202 //skip last 5 bit parity test for simplicity.
208 //demodulates strong heavily clipped samples
209 int cleanAskRawDemod ( uint8_t * BinStream
, size_t * size
, int clk
, int invert
, int high
, int low
)
211 size_t bitCnt
= 0 , smplCnt
= 0 , errCnt
= 0 ;
212 uint8_t waveHigh
= 0 ;
213 for ( size_t i
= 0 ; i
< * size
; i
++){
214 if ( BinStream
[ i
] >= high
&& waveHigh
){
216 } else if ( BinStream
[ i
] <= low
&& ! waveHigh
){
218 } else { //transition
219 if (( BinStream
[ i
] >= high
&& ! waveHigh
) || ( BinStream
[ i
] <= low
&& waveHigh
)){
220 if ( smplCnt
> clk
-( clk
/ 4 )- 1 ) { //full clock
221 if ( smplCnt
> clk
+ ( clk
/ 4 )+ 1 ) { //too many samples
223 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: Modulation Error at: %u" , i
);
224 BinStream
[ bitCnt
++]= 7 ;
225 } else if ( waveHigh
) {
226 BinStream
[ bitCnt
++] = invert
;
227 BinStream
[ bitCnt
++] = invert
;
228 } else if (! waveHigh
) {
229 BinStream
[ bitCnt
++] = invert
^ 1 ;
230 BinStream
[ bitCnt
++] = invert
^ 1 ;
234 } else if ( smplCnt
> ( clk
/ 2 ) - ( clk
/ 4 )- 1 ) {
236 BinStream
[ bitCnt
++] = invert
;
237 } else if (! waveHigh
) {
238 BinStream
[ bitCnt
++] = invert
^ 1 ;
242 } else if (! bitCnt
) {
244 waveHigh
= ( BinStream
[ i
] >= high
);
248 //transition bit oops
250 } else { //haven't hit new high or new low yet
260 void askAmp ( uint8_t * BitStream
, size_t size
)
262 for ( size_t i
= 1 ; i
< size
; i
++){
263 if ( BitStream
[ i
]- BitStream
[ i
- 1 ]>= 30 ) //large jump up
265 else if ( BitStream
[ i
]- BitStream
[ i
- 1 ]<=- 20 ) //large jump down
272 //attempts to demodulate ask modulations, askType == 0 for ask/raw, askType==1 for ask/manchester
273 int askdemod ( uint8_t * BinStream
, size_t * size
, int * clk
, int * invert
, int maxErr
, uint8_t amp
, uint8_t askType
)
275 if (* size
== 0 ) return - 1 ;
276 int start
= DetectASKClock ( BinStream
, * size
, clk
, maxErr
); //clock default
277 if (* clk
== 0 || start
< 0 ) return - 3 ;
278 if (* invert
!= 1 ) * invert
= 0 ;
279 if ( amp
== 1 ) askAmp ( BinStream
, * size
);
280 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: clk %d, beststart %d" , * clk
, start
);
282 uint8_t initLoopMax
= 255 ;
283 if ( initLoopMax
> * size
) initLoopMax
= * size
;
284 // Detect high and lows
285 //25% clip in case highs and lows aren't clipped [marshmellow]
287 if ( getHiLo ( BinStream
, initLoopMax
, & high
, & low
, 75 , 75 ) < 1 )
288 return - 2 ; //just noise
291 // if clean clipped waves detected run alternate demod
292 if ( DetectCleanAskWave ( BinStream
, * size
, high
, low
)) {
293 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: Clean Wave Detected - using clean wave demod" );
294 errCnt
= cleanAskRawDemod ( BinStream
, size
, * clk
, * invert
, high
, low
);
295 if ( askType
) //askman
296 return manrawdecode ( BinStream
, size
, 0 );
300 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: Weak Wave Detected - using weak wave demod" );
302 int lastBit
; //set first clock check - can go negative
303 size_t i
, bitnum
= 0 ; //output counter
305 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
306 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
307 size_t MaxBits
= 3072 ; //max bits to collect
308 lastBit
= start
- * clk
;
310 for ( i
= start
; i
< * size
; ++ i
) {
311 if ( i
- lastBit
>= * clk
- tol
){
312 if ( BinStream
[ i
] >= high
) {
313 BinStream
[ bitnum
++] = * invert
;
314 } else if ( BinStream
[ i
] <= low
) {
315 BinStream
[ bitnum
++] = * invert
^ 1 ;
316 } else if ( i
- lastBit
>= * clk
+ tol
) {
318 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: Modulation Error at: %u" , i
);
319 BinStream
[ bitnum
++]= 7 ;
322 } else { //in tolerance - looking for peak
327 } else if ( i
- lastBit
>= (* clk
/ 2 - tol
) && ! midBit
&& ! askType
){
328 if ( BinStream
[ i
] >= high
) {
329 BinStream
[ bitnum
++] = * invert
;
330 } else if ( BinStream
[ i
] <= low
) {
331 BinStream
[ bitnum
++] = * invert
^ 1 ;
332 } else if ( i
- lastBit
>= * clk
/ 2 + tol
) {
333 BinStream
[ bitnum
] = BinStream
[ bitnum
- 1 ];
335 } else { //in tolerance - looking for peak
340 if ( bitnum
>= MaxBits
) break ;
347 //take 10 and 01 and manchester decode
348 //run through 2 times and take least errCnt
349 int manrawdecode ( uint8_t * BitStream
, size_t * size
, uint8_t invert
)
351 uint16_t bitnum
= 0 , MaxBits
= 512 , errCnt
= 0 ;
353 uint16_t bestErr
= 1000 , bestRun
= 0 ;
354 if (* size
< 16 ) return - 1 ;
355 //find correct start position [alignment]
356 for ( ii
= 0 ; ii
< 2 ;++ ii
){
357 for ( i
= ii
; i
<* size
- 3 ; i
+= 2 )
358 if ( BitStream
[ i
]== BitStream
[ i
+ 1 ])
368 for ( i
= bestRun
; i
< * size
- 3 ; i
+= 2 ){
369 if ( BitStream
[ i
] == 1 && ( BitStream
[ i
+ 1 ] == 0 )){
370 BitStream
[ bitnum
++]= invert
;
371 } else if (( BitStream
[ i
] == 0 ) && BitStream
[ i
+ 1 ] == 1 ){
372 BitStream
[ bitnum
++]= invert
^ 1 ;
374 BitStream
[ bitnum
++]= 7 ;
376 if ( bitnum
> MaxBits
) break ;
382 uint32_t manchesterEncode2Bytes ( uint16_t datain
) {
385 for ( uint8_t i
= 0 ; i
< 16 ; i
++) {
386 curBit
= ( datain
>> ( 15 - i
) & 1 );
387 output
|= ( 1 <<((( 15 - i
)* 2 )+ curBit
));
393 //encode binary data into binary manchester
394 int ManchesterEncode ( uint8_t * BitStream
, size_t size
)
396 size_t modIdx
= 20000 , i
= 0 ;
397 if ( size
> modIdx
) return - 1 ;
398 for ( size_t idx
= 0 ; idx
< size
; idx
++){
399 BitStream
[ idx
+ modIdx
++] = BitStream
[ idx
];
400 BitStream
[ idx
+ modIdx
++] = BitStream
[ idx
]^ 1 ;
402 for (; i
<( size
* 2 ); i
++){
403 BitStream
[ i
] = BitStream
[ i
+ 20000 ];
409 //take 01 or 10 = 1 and 11 or 00 = 0
410 //check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010
411 //decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding
412 int BiphaseRawDecode ( uint8_t * BitStream
, size_t * size
, int offset
, int invert
)
417 uint16_t MaxBits
= 512 ;
418 //if not enough samples - error
419 if (* size
< 51 ) return - 1 ;
420 //check for phase change faults - skip one sample if faulty
421 uint8_t offsetA
= 1 , offsetB
= 1 ;
423 if ( BitStream
[ i
+ 1 ]== BitStream
[ i
+ 2 ]) offsetA
= 0 ;
424 if ( BitStream
[ i
+ 2 ]== BitStream
[ i
+ 3 ]) offsetB
= 0 ;
426 if (! offsetA
&& offsetB
) offset
++;
427 for ( i
= offset
; i
<* size
- 3 ; i
+= 2 ){
428 //check for phase error
429 if ( BitStream
[ i
+ 1 ]== BitStream
[ i
+ 2 ]) {
430 BitStream
[ bitnum
++]= 7 ;
433 if (( BitStream
[ i
]== 1 && BitStream
[ i
+ 1 ]== 0 ) || ( BitStream
[ i
]== 0 && BitStream
[ i
+ 1 ]== 1 )){
434 BitStream
[ bitnum
++]= 1 ^ invert
;
435 } else if (( BitStream
[ i
]== 0 && BitStream
[ i
+ 1 ]== 0 ) || ( BitStream
[ i
]== 1 && BitStream
[ i
+ 1 ]== 1 )){
436 BitStream
[ bitnum
++]= invert
;
438 BitStream
[ bitnum
++]= 7 ;
441 if ( bitnum
> MaxBits
) break ;
448 // demod gProxIIDemod
449 // error returns as -x
450 // success returns start position in BitStream
451 // BitStream must contain previously askrawdemod and biphasedemoded data
452 int gProxII_Demod ( uint8_t BitStream
[], size_t * size
)
455 uint8_t preamble
[] = { 1 , 1 , 1 , 1 , 1 , 0 };
457 uint8_t errChk
= preambleSearch ( BitStream
, preamble
, sizeof ( preamble
), size
, & startIdx
);
458 if ( errChk
== 0 ) return - 3 ; //preamble not found
459 if (* size
!= 96 ) return - 2 ; //should have found 96 bits
460 //check first 6 spacer bits to verify format
461 if (! BitStream
[ startIdx
+ 5 ] && ! BitStream
[ startIdx
+ 10 ] && ! BitStream
[ startIdx
+ 15 ] && ! BitStream
[ startIdx
+ 20 ] && ! BitStream
[ startIdx
+ 25 ] && ! BitStream
[ startIdx
+ 30 ]){
462 //confirmed proper separator bits found
463 //return start position
464 return ( int ) startIdx
;
466 return - 5 ; //spacer bits not found - not a valid gproxII
469 //translate wave to 11111100000 (1 for each short wave [higher freq] 0 for each long wave [lower freq])
470 size_t fsk_wave_demod ( uint8_t * dest
, size_t size
, uint8_t fchigh
, uint8_t fclow
)
472 size_t last_transition
= 0 ;
475 if ( fchigh
== 0 ) fchigh
= 10 ;
476 if ( fclow
== 0 ) fclow
= 8 ;
477 //set the threshold close to 0 (graph) or 128 std to avoid static
478 uint8_t threshold_value
= 123 ;
479 size_t preLastSample
= 0 ;
480 size_t LastSample
= 0 ;
481 size_t currSample
= 0 ;
482 // sync to first lo-hi transition, and threshold
484 // Need to threshold first sample
485 // skip 160 samples to allow antenna/samples to settle
486 if ( dest
[ 160 ] < threshold_value
) dest
[ 0 ] = 0 ;
490 // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
491 // or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere
492 // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
493 // (could also be fc/5 && fc/7 for fsk1 = 4-9)
494 for ( idx
= 161 ; idx
< size
- 20 ; idx
++) {
495 // threshold current value
497 if ( dest
[ idx
] < threshold_value
) dest
[ idx
] = 0 ;
500 // Check for 0->1 transition
501 if ( dest
[ idx
- 1 ] < dest
[ idx
]) {
502 preLastSample
= LastSample
;
503 LastSample
= currSample
;
504 currSample
= idx
- last_transition
;
505 if ( currSample
< ( fclow
- 2 )){ //0-5 = garbage noise (or 0-3)
506 //do nothing with extra garbage
507 } else if ( currSample
< ( fchigh
- 1 )) { //6-8 = 8 sample waves (or 3-6 = 5)
508 //correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5)
509 if ( LastSample
> ( fchigh
- 2 ) && ( preLastSample
< ( fchigh
- 1 ) || preLastSample
== 0 )){
514 } else if ( currSample
> ( fchigh
) && ! numBits
) { //12 + and first bit = unusable garbage
515 //do nothing with beginning garbage
516 } else if ( currSample
== ( fclow
+ 1 ) && LastSample
== ( fclow
- 1 )) { // had a 7 then a 9 should be two 8's (or 4 then a 6 should be two 5's)
518 } else { //9+ = 10 sample waves (or 6+ = 7)
521 last_transition
= idx
;
524 return numBits
; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0
527 //translate 11111100000 to 10
528 //rfLen = clock, fchigh = larger field clock, fclow = smaller field clock
529 size_t aggregate_bits ( uint8_t * dest
, size_t size
, uint8_t rfLen
,
530 uint8_t invert
, uint8_t fchigh
, uint8_t fclow
)
532 uint8_t lastval
= dest
[ 0 ];
536 for ( idx
= 1 ; idx
< size
; idx
++) {
538 if ( dest
[ idx
]== lastval
) continue ;
540 //find out how many bits (n) we collected
541 //if lastval was 1, we have a 1->0 crossing
542 if ( dest
[ idx
- 1 ]== 1 ) {
543 n
= ( n
* fclow
+ rfLen
/ 2 ) / rfLen
;
544 } else { // 0->1 crossing
545 n
= ( n
* fchigh
+ rfLen
/ 2 ) / rfLen
;
549 //add to our destination the bits we collected
550 memset ( dest
+ numBits
, dest
[ idx
- 1 ]^ invert
, n
);
555 // if valid extra bits at the end were all the same frequency - add them in
556 if ( n
> rfLen
/ fchigh
) {
557 if ( dest
[ idx
- 2 ]== 1 ) {
558 n
= ( n
* fclow
+ rfLen
/ 2 ) / rfLen
;
560 n
= ( n
* fchigh
+ rfLen
/ 2 ) / rfLen
;
562 memset ( dest
+ numBits
, dest
[ idx
- 1 ]^ invert
, n
);
568 //by marshmellow (from holiman's base)
569 // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod)
570 int fskdemod ( uint8_t * dest
, size_t size
, uint8_t rfLen
, uint8_t invert
, uint8_t fchigh
, uint8_t fclow
)
573 size
= fsk_wave_demod ( dest
, size
, fchigh
, fclow
);
574 size
= aggregate_bits ( dest
, size
, rfLen
, invert
, fchigh
, fclow
);
578 // loop to get raw HID waveform then FSK demodulate the TAG ID from it
579 int HIDdemodFSK ( uint8_t * dest
, size_t * size
, uint32_t * hi2
, uint32_t * hi
, uint32_t * lo
)
581 if ( justNoise ( dest
, * size
)) return - 1 ;
583 size_t numStart
= 0 , size2
=* size
, startIdx
= 0 ;
585 * size
= fskdemod ( dest
, size2
, 50 , 1 , 10 , 8 ); //fsk2a
586 if (* size
< 96 * 2 ) return - 2 ;
587 // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
588 uint8_t preamble
[] = { 0 , 0 , 0 , 1 , 1 , 1 , 0 , 1 };
589 // find bitstring in array
590 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
591 if ( errChk
== 0 ) return - 3 ; //preamble not found
593 numStart
= startIdx
+ sizeof ( preamble
);
594 // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
595 for ( size_t idx
= numStart
; ( idx
- numStart
) < * size
- sizeof ( preamble
); idx
+= 2 ){
596 if ( dest
[ idx
] == dest
[ idx
+ 1 ]){
597 return - 4 ; //not manchester data
599 * hi2
= (* hi2
<< 1 )|(* hi
>> 31 );
600 * hi
= (* hi
<< 1 )|(* lo
>> 31 );
601 //Then, shift in a 0 or one into low
602 if ( dest
[ idx
] && ! dest
[ idx
+ 1 ]) // 1 0
607 return ( int ) startIdx
;
610 // loop to get raw paradox waveform then FSK demodulate the TAG ID from it
611 int ParadoxdemodFSK ( uint8_t * dest
, size_t * size
, uint32_t * hi2
, uint32_t * hi
, uint32_t * lo
)
613 if ( justNoise ( dest
, * size
)) return - 1 ;
615 size_t numStart
= 0 , size2
=* size
, startIdx
= 0 ;
617 * size
= fskdemod ( dest
, size2
, 50 , 1 , 10 , 8 ); //fsk2a
618 if (* size
< 96 ) return - 2 ;
620 // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
621 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 1 , 1 , 1 , 1 };
623 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
624 if ( errChk
== 0 ) return - 3 ; //preamble not found
626 numStart
= startIdx
+ sizeof ( preamble
);
627 // final loop, go over previously decoded FSK data and manchester decode into usable tag ID
628 for ( size_t idx
= numStart
; ( idx
- numStart
) < * size
- sizeof ( preamble
); idx
+= 2 ){
629 if ( dest
[ idx
] == dest
[ idx
+ 1 ])
630 return - 4 ; //not manchester data
631 * hi2
= (* hi2
<< 1 )|(* hi
>> 31 );
632 * hi
= (* hi
<< 1 )|(* lo
>> 31 );
633 //Then, shift in a 0 or one into low
634 if ( dest
[ idx
] && ! dest
[ idx
+ 1 ]) // 1 0
639 return ( int ) startIdx
;
642 int IOdemodFSK ( uint8_t * dest
, size_t size
)
644 if ( justNoise ( dest
, size
)) return - 1 ;
645 //make sure buffer has data
646 if ( size
< 66 * 64 ) return - 2 ;
648 size
= fskdemod ( dest
, size
, 64 , 1 , 10 , 8 ); // FSK2a RF/64
649 if ( size
< 65 ) return - 3 ; //did we get a good demod?
651 //0 10 20 30 40 50 60
653 //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23
654 //-----------------------------------------------------------------------------
655 //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11
657 //XSF(version)facility:codeone+codetwo
660 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 1 };
661 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), & size
, & startIdx
);
662 if ( errChk
== 0 ) return - 4 ; //preamble not found
664 if (! dest
[ startIdx
+ 8 ] && dest
[ startIdx
+ 17 ]== 1 && dest
[ startIdx
+ 26 ]== 1 && dest
[ startIdx
+ 35 ]== 1 && dest
[ startIdx
+ 44 ]== 1 && dest
[ startIdx
+ 53 ]== 1 ){
665 //confirmed proper separator bits found
666 //return start position
667 return ( int ) startIdx
;
673 // find viking preamble 0xF200 in already demoded data
674 int VikingDemod_AM ( uint8_t * dest
, size_t * size
) {
675 //make sure buffer has data
676 if (* size
< 64 * 2 ) return - 2 ;
679 uint8_t preamble
[] = { 1 , 1 , 1 , 1 , 0 , 0 , 1 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
680 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
681 if ( errChk
== 0 ) return - 4 ; //preamble not found
682 uint32_t checkCalc
= bytebits_to_byte ( dest
+ startIdx
, 8 ) ^
683 bytebits_to_byte ( dest
+ startIdx
+ 8 , 8 ) ^
684 bytebits_to_byte ( dest
+ startIdx
+ 16 , 8 ) ^
685 bytebits_to_byte ( dest
+ startIdx
+ 24 , 8 ) ^
686 bytebits_to_byte ( dest
+ startIdx
+ 32 , 8 ) ^
687 bytebits_to_byte ( dest
+ startIdx
+ 40 , 8 ) ^
688 bytebits_to_byte ( dest
+ startIdx
+ 48 , 8 ) ^
689 bytebits_to_byte ( dest
+ startIdx
+ 56 , 8 );
690 if ( checkCalc
!= 0xA8 ) return - 5 ;
691 if (* size
!= 64 ) return - 6 ;
692 //return start position
693 return ( int ) startIdx
;
696 // find presco preamble 0x10D in already demoded data
697 int PrescoDemod ( uint8_t * dest
, size_t * size
) {
698 //make sure buffer has data
699 if (* size
< 64 * 2 ) return - 2 ;
702 uint8_t preamble
[] = { 1 , 0 , 0 , 0 , 0 , 1 , 1 , 0 , 1 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
703 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
704 if ( errChk
== 0 ) return - 4 ; //preamble not found
705 //return start position
706 return ( int ) startIdx
;
709 // Ask/Biphase Demod then try to locate an ISO 11784/85 ID
710 // BitStream must contain previously askrawdemod and biphasedemoded data
711 int FDXBdemodBI ( uint8_t * dest
, size_t * size
)
713 //make sure buffer has enough data
714 if (* size
< 128 ) return - 1 ;
717 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 1 };
719 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
720 if ( errChk
== 0 ) return - 2 ; //preamble not found
721 return ( int ) startIdx
;
725 // FSK Demod then try to locate an AWID ID
726 int AWIDdemodFSK ( uint8_t * dest
, size_t * size
)
728 //make sure buffer has enough data
729 if (* size
< 96 * 50 ) return - 1 ;
731 if ( justNoise ( dest
, * size
)) return - 2 ;
734 * size
= fskdemod ( dest
, * size
, 50 , 1 , 10 , 8 ); // fsk2a RF/50
735 if (* size
< 96 ) return - 3 ; //did we get a good demod?
737 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 1 };
739 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
740 if ( errChk
== 0 ) return - 4 ; //preamble not found
741 if (* size
!= 96 ) return - 5 ;
742 return ( int ) startIdx
;
746 // FSK Demod then try to locate a Farpointe Data (pyramid) ID
747 int PyramiddemodFSK ( uint8_t * dest
, size_t * size
)
749 //make sure buffer has data
750 if (* size
< 128 * 50 ) return - 5 ;
752 //test samples are not just noise
753 if ( justNoise ( dest
, * size
)) return - 1 ;
756 * size
= fskdemod ( dest
, * size
, 50 , 1 , 10 , 8 ); // fsk2a RF/50
757 if (* size
< 128 ) return - 2 ; //did we get a good demod?
759 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 1 };
761 uint8_t errChk
= preambleSearch ( dest
, preamble
, sizeof ( preamble
), size
, & startIdx
);
762 if ( errChk
== 0 ) return - 4 ; //preamble not found
763 if (* size
!= 128 ) return - 3 ;
764 return ( int ) startIdx
;
768 // to detect a wave that has heavily clipped (clean) samples
769 uint8_t DetectCleanAskWave ( uint8_t dest
[], size_t size
, uint8_t high
, uint8_t low
)
771 bool allArePeaks
= true ;
773 size_t loopEnd
= 512 + 160 ;
774 if ( loopEnd
> size
) loopEnd
= size
;
775 for ( size_t i
= 160 ; i
< loopEnd
; i
++){
776 if ( dest
[ i
]> low
&& dest
[ i
]< high
)
782 if ( cntPeaks
> 300 ) return true ;
787 // to help detect clocks on heavily clipped samples
788 // based on count of low to low
789 int DetectStrongAskClock ( uint8_t dest
[], size_t size
, uint8_t high
, uint8_t low
)
791 uint8_t fndClk
[] = { 8 , 16 , 32 , 40 , 50 , 64 , 128 };
795 // get to first full low to prime loop and skip incomplete first pulse
796 while (( dest
[ i
] < high
) && ( i
< size
))
798 while (( dest
[ i
] > low
) && ( i
< size
))
801 // loop through all samples
803 // measure from low to low
804 while (( dest
[ i
] > low
) && ( i
< size
))
807 while (( dest
[ i
] < high
) && ( i
< size
))
809 while (( dest
[ i
] > low
) && ( i
< size
))
811 //get minimum measured distance
812 if ( i
- startwave
< minClk
&& i
< size
)
813 minClk
= i
- startwave
;
816 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: detectstrongASKclk smallest wave: %d" , minClk
);
817 for ( uint8_t clkCnt
= 0 ; clkCnt
< 7 ; clkCnt
++) {
818 if ( minClk
>= fndClk
[ clkCnt
]-( fndClk
[ clkCnt
]/ 8 ) && minClk
<= fndClk
[ clkCnt
]+ 1 )
819 return fndClk
[ clkCnt
];
825 // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping)
826 // maybe somehow adjust peak trimming value based on samples to fix?
827 // return start index of best starting position for that clock and return clock (by reference)
828 int DetectASKClock ( uint8_t dest
[], size_t size
, int * clock
, int maxErr
)
831 uint8_t clk
[] = { 255 , 8 , 16 , 32 , 40 , 50 , 64 , 100 , 128 , 255 };
833 uint8_t loopCnt
= 255 ; //don't need to loop through entire array...
834 if ( size
<= loopCnt
+ 60 ) return - 1 ; //not enough samples
835 size
-= 60 ; //sometimes there is a strange end wave - filter out this....
836 //if we already have a valid clock
839 if ( clk
[ i
] == * clock
) clockFnd
= i
;
840 //clock found but continue to find best startpos
842 //get high and low peak
844 if ( getHiLo ( dest
, loopCnt
, & peak
, & low
, 75 , 75 ) < 1 ) return - 1 ;
846 //test for large clean peaks
848 if ( DetectCleanAskWave ( dest
, size
, peak
, low
)== 1 ){
849 int ans
= DetectStrongAskClock ( dest
, size
, peak
, low
);
850 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %d" , ans
);
851 for ( i
= clkEnd
- 1 ; i
> 0 ; i
--){
855 return 0 ; // for strong waves i don't use the 'best start position' yet...
856 //break; //clock found but continue to find best startpos [not yet]
862 uint8_t clkCnt
, tol
= 0 ;
863 uint16_t bestErr
[]={ 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 };
864 uint8_t bestStart
[]={ 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
866 size_t arrLoc
, loopEnd
;
874 //test each valid clock from smallest to greatest to see which lines up
875 for (; clkCnt
< clkEnd
; clkCnt
++){
876 if ( clk
[ clkCnt
] <= 32 ){
881 //if no errors allowed - keep start within the first clock
882 if (! maxErr
&& size
> clk
[ clkCnt
]* 2 + tol
&& clk
[ clkCnt
]< 128 ) loopCnt
= clk
[ clkCnt
]* 2 ;
883 bestErr
[ clkCnt
]= 1000 ;
884 //try lining up the peaks by moving starting point (try first few clocks)
885 for ( ii
= 0 ; ii
< loopCnt
; ii
++){
886 if ( dest
[ ii
] < peak
&& dest
[ ii
] > low
) continue ;
889 // now that we have the first one lined up test rest of wave array
890 loopEnd
= (( size
- ii
- tol
) / clk
[ clkCnt
]) - 1 ;
891 for ( i
= 0 ; i
< loopEnd
; ++ i
){
892 arrLoc
= ii
+ ( i
* clk
[ clkCnt
]);
893 if ( dest
[ arrLoc
] >= peak
|| dest
[ arrLoc
] <= low
){
894 } else if ( dest
[ arrLoc
- tol
] >= peak
|| dest
[ arrLoc
- tol
] <= low
){
895 } else if ( dest
[ arrLoc
+ tol
] >= peak
|| dest
[ arrLoc
+ tol
] <= low
){
896 } else { //error no peak detected
900 //if we found no errors then we can stop here and a low clock (common clocks)
901 // this is correct one - return this clock
902 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: clk %d, err %d, startpos %d, endpos %d" , clk
[ clkCnt
], errCnt
, ii
, i
);
903 if ( errCnt
== 0 && clkCnt
< 7 ) {
904 if (! clockFnd
) * clock
= clk
[ clkCnt
];
907 //if we found errors see if it is lowest so far and save it as best run
908 if ( errCnt
< bestErr
[ clkCnt
]){
909 bestErr
[ clkCnt
]= errCnt
;
910 bestStart
[ clkCnt
]= ii
;
916 for ( iii
= 1 ; iii
< clkEnd
; ++ iii
){
917 if ( bestErr
[ iii
] < bestErr
[ best
]){
918 if ( bestErr
[ iii
] == 0 ) bestErr
[ iii
]= 1 ;
919 // current best bit to error ratio vs new bit to error ratio
920 if ( ( size
/ clk
[ best
])/ bestErr
[ best
] < ( size
/ clk
[ iii
])/ bestErr
[ iii
] ){
924 if ( g_debugMode
== 2 ) prnt ( "DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d" , clk
[ iii
], bestErr
[ iii
], clk
[ best
], bestStart
[ best
]);
926 if (! clockFnd
) * clock
= clk
[ best
];
927 return bestStart
[ best
];
931 //detect psk clock by reading each phase shift
932 // a phase shift is determined by measuring the sample length of each wave
933 int DetectPSKClock ( uint8_t dest
[], size_t size
, int clock
)
935 uint8_t clk
[]={ 255 , 16 , 32 , 40 , 50 , 64 , 100 , 128 , 255 }; //255 is not a valid clock
936 uint16_t loopCnt
= 4096 ; //don't need to loop through entire array...
937 if ( size
== 0 ) return 0 ;
938 if ( size
< loopCnt
) loopCnt
= size
- 20 ;
940 //if we already have a valid clock quit
943 if ( clk
[ i
] == clock
) return clock
;
945 size_t waveStart
= 0 , waveEnd
= 0 , firstFullWave
= 0 , lastClkBit
= 0 ;
946 uint8_t clkCnt
, fc
= 0 , fullWaveLen
= 0 , tol
= 1 ;
947 uint16_t peakcnt
= 0 , errCnt
= 0 , waveLenCnt
= 0 ;
948 uint16_t bestErr
[]={ 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 , 1000 };
949 uint16_t peaksdet
[]={ 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
950 fc
= countFC ( dest
, size
, 0 );
951 if ( fc
!= 2 && fc
!= 4 && fc
!= 8 ) return - 1 ;
952 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: FC: %d" , fc
);
954 //find first full wave
955 for ( i
= 160 ; i
< loopCnt
; i
++){
956 if ( dest
[ i
] < dest
[ i
+ 1 ] && dest
[ i
+ 1 ] >= dest
[ i
+ 2 ]){
957 if ( waveStart
== 0 ) {
959 //prnt("DEBUG: waveStart: %d",waveStart);
962 //prnt("DEBUG: waveEnd: %d",waveEnd);
963 waveLenCnt
= waveEnd
- waveStart
;
964 if ( waveLenCnt
> fc
){
965 firstFullWave
= waveStart
;
966 fullWaveLen
= waveLenCnt
;
973 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: firstFullWave: %d, waveLen: %d" , firstFullWave
, fullWaveLen
);
975 //test each valid clock from greatest to smallest to see which lines up
976 for ( clkCnt
= 7 ; clkCnt
>= 1 ; clkCnt
--){
977 lastClkBit
= firstFullWave
; //set end of wave as clock align
981 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: clk: %d, lastClkBit: %d" , clk
[ clkCnt
], lastClkBit
);
983 for ( i
= firstFullWave
+ fullWaveLen
- 1 ; i
< loopCnt
- 2 ; i
++){
984 //top edge of wave = start of new wave
985 if ( dest
[ i
] < dest
[ i
+ 1 ] && dest
[ i
+ 1 ] >= dest
[ i
+ 2 ]){
986 if ( waveStart
== 0 ) {
991 waveLenCnt
= waveEnd
- waveStart
;
992 if ( waveLenCnt
> fc
){
993 //if this wave is a phase shift
994 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d" , waveStart
, waveLenCnt
, lastClkBit
+ clk
[ clkCnt
]- tol
, i
+ 1 , fc
);
995 if ( i
+ 1 >= lastClkBit
+ clk
[ clkCnt
] - tol
){ //should be a clock bit
997 lastClkBit
+= clk
[ clkCnt
];
998 } else if ( i
< lastClkBit
+ 8 ){
999 //noise after a phase shift - ignore
1000 } else { //phase shift before supposed to based on clock
1003 } else if ( i
+ 1 > lastClkBit
+ clk
[ clkCnt
] + tol
+ fc
){
1004 lastClkBit
+= clk
[ clkCnt
]; //no phase shift but clock bit
1013 if ( errCnt
<= bestErr
[ clkCnt
]) bestErr
[ clkCnt
]= errCnt
;
1014 if ( peakcnt
> peaksdet
[ clkCnt
]) peaksdet
[ clkCnt
]= peakcnt
;
1016 //all tested with errors
1017 //return the highest clk with the most peaks found
1019 for ( i
= 7 ; i
>= 1 ; i
--){
1020 if ( peaksdet
[ i
] > peaksdet
[ best
]) {
1023 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: Clk: %d, peaks: %d, errs: %d, bestClk: %d" , clk
[ i
], peaksdet
[ i
], bestErr
[ i
], clk
[ best
]);
1028 int DetectStrongNRZClk ( uint8_t * dest
, size_t size
, int peak
, int low
){
1029 //find shortest transition from high to low
1031 size_t transition1
= 0 ;
1032 int lowestTransition
= 255 ;
1033 bool lastWasHigh
= false ;
1035 //find first valid beginning of a high or low wave
1036 while (( dest
[ i
] >= peak
|| dest
[ i
] <= low
) && ( i
< size
))
1038 while (( dest
[ i
] < peak
&& dest
[ i
] > low
) && ( i
< size
))
1040 lastWasHigh
= ( dest
[ i
] >= peak
);
1042 if ( i
== size
) return 0 ;
1045 for (; i
< size
; i
++) {
1046 if (( dest
[ i
] >= peak
&& ! lastWasHigh
) || ( dest
[ i
] <= low
&& lastWasHigh
)) {
1047 lastWasHigh
= ( dest
[ i
] >= peak
);
1048 if ( i
- transition1
< lowestTransition
) lowestTransition
= i
- transition1
;
1052 if ( lowestTransition
== 255 ) lowestTransition
= 0 ;
1053 if ( g_debugMode
== 2 ) prnt ( "DEBUG NRZ: detectstrongNRZclk smallest wave: %d" , lowestTransition
);
1054 return lowestTransition
;
1058 //detect nrz clock by reading #peaks vs no peaks(or errors)
1059 int DetectNRZClock ( uint8_t dest
[], size_t size
, int clock
)
1062 uint8_t clk
[]={ 8 , 16 , 32 , 40 , 50 , 64 , 100 , 128 , 255 };
1063 size_t loopCnt
= 4096 ; //don't need to loop through entire array...
1064 if ( size
== 0 ) return 0 ;
1065 if ( size
< loopCnt
) loopCnt
= size
- 20 ;
1066 //if we already have a valid clock quit
1068 if ( clk
[ i
] == clock
) return clock
;
1070 //get high and low peak
1072 if ( getHiLo ( dest
, loopCnt
, & peak
, & low
, 75 , 75 ) < 1 ) return 0 ;
1074 int lowestTransition
= DetectStrongNRZClk ( dest
, size
- 20 , peak
, low
);
1078 uint16_t smplCnt
= 0 ;
1079 int16_t peakcnt
= 0 ;
1080 int16_t peaksdet
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
1081 uint16_t maxPeak
= 255 ;
1082 bool firstpeak
= false ;
1083 //test for large clipped waves
1084 for ( i
= 0 ; i
< loopCnt
; i
++){
1085 if ( dest
[ i
] >= peak
|| dest
[ i
] <= low
){
1086 if (! firstpeak
) continue ;
1091 if ( maxPeak
> smplCnt
){
1093 //prnt("maxPk: %d",maxPeak);
1096 //prnt("maxPk: %d, smplCnt: %d, peakcnt: %d",maxPeak,smplCnt,peakcnt);
1101 bool errBitHigh
= 0 ;
1103 uint8_t ignoreCnt
= 0 ;
1104 uint8_t ignoreWindow
= 4 ;
1105 bool lastPeakHigh
= 0 ;
1108 //test each valid clock from smallest to greatest to see which lines up
1109 for ( clkCnt
= 0 ; clkCnt
< 8 ; ++ clkCnt
){
1110 //ignore clocks smaller than smallest peak
1111 if ( clk
[ clkCnt
] < maxPeak
- ( clk
[ clkCnt
]/ 4 )) continue ;
1112 //try lining up the peaks by moving starting point (try first 256)
1113 for ( ii
= 20 ; ii
< loopCnt
; ++ ii
){
1114 if (( dest
[ ii
] >= peak
) || ( dest
[ ii
] <= low
)){
1118 lastBit
= ii
- clk
[ clkCnt
];
1119 //loop through to see if this start location works
1120 for ( i
= ii
; i
< size
- 20 ; ++ i
) {
1121 //if we are at a clock bit
1122 if (( i
>= lastBit
+ clk
[ clkCnt
] - tol
) && ( i
<= lastBit
+ clk
[ clkCnt
] + tol
)) {
1124 if ( dest
[ i
] >= peak
|| dest
[ i
] <= low
) {
1125 //if same peak don't count it
1126 if (( dest
[ i
] >= peak
&& ! lastPeakHigh
) || ( dest
[ i
] <= low
&& lastPeakHigh
)) {
1129 lastPeakHigh
= ( dest
[ i
] >= peak
);
1132 ignoreCnt
= ignoreWindow
;
1133 lastBit
+= clk
[ clkCnt
];
1134 } else if ( i
== lastBit
+ clk
[ clkCnt
] + tol
) {
1135 lastBit
+= clk
[ clkCnt
];
1137 //else if not a clock bit and no peaks
1138 } else if ( dest
[ i
] < peak
&& dest
[ i
] > low
){
1141 if ( errBitHigh
== true ) peakcnt
--;
1146 // else if not a clock bit but we have a peak
1147 } else if (( dest
[ i
]>= peak
|| dest
[ i
]<= low
) && (! bitHigh
)) {
1148 //error bar found no clock...
1152 if ( peakcnt
> peaksdet
[ clkCnt
]) {
1153 peaksdet
[ clkCnt
]= peakcnt
;
1160 for ( iii
= 7 ; iii
> 0 ; iii
--){
1161 if (( peaksdet
[ iii
] >= ( peaksdet
[ best
]- 1 )) && ( peaksdet
[ iii
] <= peaksdet
[ best
]+ 1 ) && lowestTransition
) {
1162 if ( clk
[ iii
] > ( lowestTransition
- ( clk
[ iii
]/ 8 )) && clk
[ iii
] < ( lowestTransition
+ ( clk
[ iii
]/ 8 ))) {
1165 } else if ( peaksdet
[ iii
] > peaksdet
[ best
]){
1168 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
);
1175 // convert psk1 demod to psk2 demod
1176 // only transition waves are 1s
1177 void psk1TOpsk2 ( uint8_t * BitStream
, size_t size
)
1180 uint8_t lastBit
= BitStream
[ 0 ];
1181 for (; i
< size
; i
++){
1182 if ( BitStream
[ i
]== 7 ){
1184 } else if ( lastBit
!= BitStream
[ i
]){
1185 lastBit
= BitStream
[ i
];
1195 // convert psk2 demod to psk1 demod
1196 // from only transition waves are 1s to phase shifts change bit
1197 void psk2TOpsk1 ( uint8_t * BitStream
, size_t size
)
1200 for ( size_t i
= 0 ; i
< size
; i
++){
1201 if ( BitStream
[ i
]== 1 ){
1209 // redesigned by marshmellow adjusted from existing decode functions
1210 // indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
1211 int indala26decode ( uint8_t * bitStream
, size_t * size
, uint8_t * invert
)
1213 //26 bit 40134 format (don't know other formats)
1214 uint8_t preamble
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 1 };
1215 uint8_t preamble_i
[] = { 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 1 , 0 };
1216 size_t startidx
= 0 ;
1217 if (! preambleSearch ( bitStream
, preamble
, sizeof ( preamble
), size
, & startidx
)){
1218 // if didn't find preamble try again inverting
1219 if (! preambleSearch ( bitStream
, preamble_i
, sizeof ( preamble_i
), size
, & startidx
)) return - 1 ;
1222 if (* size
!= 64 && * size
!= 224 ) return - 2 ;
1224 for ( size_t i
= startidx
; i
< * size
; i
++)
1227 return ( int ) startidx
;
1230 // by marshmellow - demodulate NRZ wave - requires a read with strong signal
1231 // peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
1232 int nrzRawDemod ( uint8_t * dest
, size_t * size
, int * clk
, int * invert
){
1233 if ( justNoise ( dest
, * size
)) return - 1 ;
1234 * clk
= DetectNRZClock ( dest
, * size
, * clk
);
1235 if (* clk
== 0 ) return - 2 ;
1236 size_t i
, gLen
= 4096 ;
1237 if ( gLen
>* size
) gLen
= * size
- 20 ;
1239 if ( getHiLo ( dest
, gLen
, & high
, & low
, 75 , 75 ) < 1 ) return - 3 ; //25% fuzz on high 25% fuzz on low
1242 //convert wave samples to 1's and 0's
1243 for ( i
= 20 ; i
< * size
- 20 ; i
++){
1244 if ( dest
[ i
] >= high
) bit
= 1 ;
1245 if ( dest
[ i
] <= low
) bit
= 0 ;
1248 //now demod based on clock (rf/32 = 32 1's for one 1 bit, 32 0's for one 0 bit)
1251 for ( i
= 21 ; i
< * size
- 20 ; i
++) {
1252 //if transition detected or large number of same bits - store the passed bits
1253 if ( dest
[ i
] != dest
[ i
- 1 ] || ( i
- lastBit
) == ( 10 * * clk
)) {
1254 memset ( dest
+ numBits
, dest
[ i
- 1 ] ^ * invert
, ( i
- lastBit
+ (* clk
/ 4 )) / * clk
);
1255 numBits
+= ( i
- lastBit
+ (* clk
/ 4 )) / * clk
;
1264 //detects the bit clock for FSK given the high and low Field Clocks
1265 uint8_t detectFSKClk ( uint8_t * BitStream
, size_t size
, uint8_t fcHigh
, uint8_t fcLow
)
1267 uint8_t clk
[] = { 8 , 16 , 32 , 40 , 50 , 64 , 100 , 128 , 0 };
1268 uint16_t rfLens
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
1269 uint8_t rfCnts
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
1270 uint8_t rfLensFnd
= 0 ;
1271 uint8_t lastFCcnt
= 0 ;
1272 uint16_t fcCounter
= 0 ;
1273 uint16_t rfCounter
= 0 ;
1274 uint8_t firstBitFnd
= 0 ;
1276 if ( size
== 0 ) return 0 ;
1278 uint8_t fcTol
= (( fcHigh
* 100 - fcLow
* 100 )/ 2 + 50 )/ 100 ; //(uint8_t)(0.5+(float)(fcHigh-fcLow)/2);
1283 //PrintAndLog("DEBUG: fcTol: %d",fcTol);
1284 // prime i to first peak / up transition
1285 for ( i
= 160 ; i
< size
- 20 ; i
++)
1286 if ( BitStream
[ i
] > BitStream
[ i
- 1 ] && BitStream
[ i
]>= BitStream
[ i
+ 1 ])
1289 for (; i
< size
- 20 ; i
++){
1293 if ( BitStream
[ i
] <= BitStream
[ i
- 1 ] || BitStream
[ i
] < BitStream
[ i
+ 1 ])
1296 // if we got less than the small fc + tolerance then set it to the small fc
1297 if ( fcCounter
< fcLow
+ fcTol
)
1299 else //set it to the large fc
1302 //look for bit clock (rf/xx)
1303 if (( fcCounter
< lastFCcnt
|| fcCounter
> lastFCcnt
)){
1304 //not the same size as the last wave - start of new bit sequence
1305 if ( firstBitFnd
> 1 ){ //skip first wave change - probably not a complete bit
1306 for ( int ii
= 0 ; ii
< 15 ; ii
++){
1307 if ( rfLens
[ ii
] >= ( rfCounter
- 4 ) && rfLens
[ ii
] <= ( rfCounter
+ 4 )){
1313 if ( rfCounter
> 0 && rfLensFnd
< 15 ){
1314 //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
1315 rfCnts
[ rfLensFnd
]++;
1316 rfLens
[ rfLensFnd
++] = rfCounter
;
1322 lastFCcnt
= fcCounter
;
1326 uint8_t rfHighest
= 15 , rfHighest2
= 15 , rfHighest3
= 15 ;
1328 for ( i
= 0 ; i
< 15 ; i
++){
1329 //get highest 2 RF values (might need to get more values to compare or compare all?)
1330 if ( rfCnts
[ i
]> rfCnts
[ rfHighest
]){
1331 rfHighest3
= rfHighest2
;
1332 rfHighest2
= rfHighest
;
1334 } else if ( rfCnts
[ i
]> rfCnts
[ rfHighest2
]){
1335 rfHighest3
= rfHighest2
;
1337 } else if ( rfCnts
[ i
]> rfCnts
[ rfHighest3
]){
1340 if ( g_debugMode
== 2 ) prnt ( "DEBUG FSK: RF %d, cnts %d" , rfLens
[ i
], rfCnts
[ i
]);
1342 // set allowed clock remainder tolerance to be 1 large field clock length+1
1343 // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off
1344 uint8_t tol1
= fcHigh
+ 1 ;
1346 if ( g_debugMode
== 2 ) prnt ( "DEBUG FSK: most counted rf values: 1 %d, 2 %d, 3 %d" , rfLens
[ rfHighest
], rfLens
[ rfHighest2
], rfLens
[ rfHighest3
]);
1348 // loop to find the highest clock that has a remainder less than the tolerance
1349 // compare samples counted divided by
1350 // test 128 down to 32 (shouldn't be possible to have fc/10 & fc/8 and rf/16 or less)
1352 for (; ii
>= 2 ; ii
--){
1353 if ( rfLens
[ rfHighest
] % clk
[ ii
] < tol1
|| rfLens
[ rfHighest
] % clk
[ ii
] > clk
[ ii
]- tol1
){
1354 if ( rfLens
[ rfHighest2
] % clk
[ ii
] < tol1
|| rfLens
[ rfHighest2
] % clk
[ ii
] > clk
[ ii
]- tol1
){
1355 if ( rfLens
[ rfHighest3
] % clk
[ ii
] < tol1
|| rfLens
[ rfHighest3
] % clk
[ ii
] > clk
[ ii
]- tol1
){
1356 if ( g_debugMode
== 2 ) prnt ( "DEBUG FSK: clk %d divides into the 3 most rf values within tolerance" , clk
[ ii
]);
1363 if ( ii
< 0 ) return 0 ; // oops we went too far
1369 //countFC is to detect the field clock lengths.
1370 //counts and returns the 2 most common wave lengths
1371 //mainly used for FSK field clock detection
1372 uint16_t countFC ( uint8_t * BitStream
, size_t size
, uint8_t fskAdj
)
1374 uint8_t fcLens
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
1375 uint16_t fcCnts
[] = { 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 };
1376 uint8_t fcLensFnd
= 0 ;
1377 uint8_t lastFCcnt
= 0 ;
1378 uint8_t fcCounter
= 0 ;
1380 if ( size
== 0 ) return 0 ;
1382 // prime i to first up transition
1383 for ( i
= 160 ; i
< size
- 20 ; i
++)
1384 if ( BitStream
[ i
] > BitStream
[ i
- 1 ] && BitStream
[ i
] >= BitStream
[ i
+ 1 ])
1387 for (; i
< size
- 20 ; i
++){
1388 if ( BitStream
[ i
] > BitStream
[ i
- 1 ] && BitStream
[ i
] >= BitStream
[ i
+ 1 ]){
1389 // new up transition
1392 //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8)
1393 if ( lastFCcnt
== 5 && fcCounter
== 9 ) fcCounter
--;
1394 //if fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5)
1395 if (( fcCounter
== 9 ) || fcCounter
== 4 ) fcCounter
++;
1396 // save last field clock count (fc/xx)
1397 lastFCcnt
= fcCounter
;
1399 // find which fcLens to save it to:
1400 for ( int ii
= 0 ; ii
< 15 ; ii
++){
1401 if ( fcLens
[ ii
]== fcCounter
){
1407 if ( fcCounter
> 0 && fcLensFnd
< 15 ){
1409 fcCnts
[ fcLensFnd
]++;
1410 fcLens
[ fcLensFnd
++]= fcCounter
;
1419 uint8_t best1
= 14 , best2
= 14 , best3
= 14 ;
1421 // go through fclens and find which ones are bigest 2
1422 for ( i
= 0 ; i
< 15 ; i
++){
1423 // get the 3 best FC values
1424 if ( fcCnts
[ i
]> maxCnt1
) {
1429 } else if ( fcCnts
[ i
]> fcCnts
[ best2
]){
1432 } else if ( fcCnts
[ i
]> fcCnts
[ best3
]){
1435 if ( g_debugMode
== 2 ) prnt ( "DEBUG countfc: FC %u, Cnt %u, best fc: %u, best2 fc: %u" , fcLens
[ i
], fcCnts
[ i
], fcLens
[ best1
], fcLens
[ best2
]);
1437 if ( fcLens
[ best1
]== 0 ) return 0 ;
1438 uint8_t fcH
= 0 , fcL
= 0 ;
1439 if ( fcLens
[ best1
]> fcLens
[ best2
]){
1446 if (( size
- 180 )/ fcH
/ 3 > fcCnts
[ best1
]+ fcCnts
[ best2
]) {
1447 if ( g_debugMode
== 2 ) prnt ( "DEBUG countfc: fc is too large: %u > %u. Not psk or fsk" ,( size
- 180 )/ fcH
/ 3 , fcCnts
[ best1
]+ fcCnts
[ best2
]);
1448 return 0 ; //lots of waves not psk or fsk
1450 // TODO: take top 3 answers and compare to known Field clocks to get top 2
1452 uint16_t fcs
= ((( uint16_t ) fcH
)<< 8 ) | fcL
;
1453 if ( fskAdj
) return fcs
;
1454 return fcLens
[ best1
];
1457 //by marshmellow - demodulate PSK1 wave
1458 //uses wave lengths (# Samples)
1459 int pskRawDemod ( uint8_t dest
[], size_t * size
, int * clock
, int * invert
)
1461 if ( size
== 0 ) return - 1 ;
1462 uint16_t loopCnt
= 4096 ; //don't need to loop through entire array...
1463 if (* size
< loopCnt
) loopCnt
= * size
;
1466 uint8_t curPhase
= * invert
;
1467 size_t i
, waveStart
= 1 , waveEnd
= 0 , firstFullWave
= 0 , lastClkBit
= 0 ;
1468 uint8_t fc
= 0 , fullWaveLen
= 0 , tol
= 1 ;
1469 uint16_t errCnt
= 0 , waveLenCnt
= 0 ;
1470 fc
= countFC ( dest
, * size
, 0 );
1471 if ( fc
!= 2 && fc
!= 4 && fc
!= 8 ) return - 1 ;
1472 //PrintAndLog("DEBUG: FC: %d",fc);
1473 * clock
= DetectPSKClock ( dest
, * size
, * clock
);
1474 if (* clock
== 0 ) return - 1 ;
1475 int avgWaveVal
= 0 , lastAvgWaveVal
= 0 ;
1476 //find first phase shift
1477 for ( i
= 0 ; i
< loopCnt
; i
++){
1478 if ( dest
[ i
]+ fc
< dest
[ i
+ 1 ] && dest
[ i
+ 1 ] >= dest
[ i
+ 2 ]){
1480 //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
1481 waveLenCnt
= waveEnd
- waveStart
;
1482 if ( waveLenCnt
> fc
&& waveStart
> fc
&& !( waveLenCnt
> fc
+ 2 )){ //not first peak and is a large wave but not out of whack
1483 lastAvgWaveVal
= avgWaveVal
/( waveLenCnt
);
1484 firstFullWave
= waveStart
;
1485 fullWaveLen
= waveLenCnt
;
1486 //if average wave value is > graph 0 then it is an up wave or a 1
1487 if ( lastAvgWaveVal
> 123 ) curPhase
^= 1 ; //fudge graph 0 a little 123 vs 128
1493 avgWaveVal
+= dest
[ i
+ 2 ];
1495 if ( firstFullWave
== 0 ) {
1496 // no phase shift detected - could be all 1's or 0's - doesn't matter where we start
1497 // so skip a little to ensure we are past any Start Signal
1498 firstFullWave
= 160 ;
1499 memset ( dest
, curPhase
, firstFullWave
/ * clock
);
1501 memset ( dest
, curPhase
^ 1 , firstFullWave
/ * clock
);
1504 numBits
+= ( firstFullWave
/ * clock
);
1505 //set start of wave as clock align
1506 lastClkBit
= firstFullWave
;
1507 if ( g_debugMode
== 2 ) prnt ( "DEBUG PSK: firstFullWave: %u, waveLen: %u" , firstFullWave
, fullWaveLen
);
1508 if ( g_debugMode
== 2 ) prnt ( "DEBUG: clk: %d, lastClkBit: %u, fc: %u" , * clock
, lastClkBit
,( unsigned int ) fc
);
1510 dest
[ numBits
++] = curPhase
; //set first read bit
1511 for ( i
= firstFullWave
+ fullWaveLen
- 1 ; i
< * size
- 3 ; i
++){
1512 //top edge of wave = start of new wave
1513 if ( dest
[ i
]+ fc
< dest
[ i
+ 1 ] && dest
[ i
+ 1 ] >= dest
[ i
+ 2 ]){
1514 if ( waveStart
== 0 ) {
1517 avgWaveVal
= dest
[ i
+ 1 ];
1520 waveLenCnt
= waveEnd
- waveStart
;
1521 lastAvgWaveVal
= avgWaveVal
/ waveLenCnt
;
1522 if ( waveLenCnt
> fc
){
1523 //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
1524 //this wave is a phase shift
1525 //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);
1526 if ( i
+ 1 >= lastClkBit
+ * clock
- tol
){ //should be a clock bit
1528 dest
[ numBits
++] = curPhase
;
1529 lastClkBit
+= * clock
;
1530 } else if ( i
< lastClkBit
+ 10 + fc
){
1531 //noise after a phase shift - ignore
1532 } else { //phase shift before supposed to based on clock
1534 dest
[ numBits
++] = 7 ;
1536 } else if ( i
+ 1 > lastClkBit
+ * clock
+ tol
+ fc
){
1537 lastClkBit
+= * clock
; //no phase shift but clock bit
1538 dest
[ numBits
++] = curPhase
;
1544 avgWaveVal
+= dest
[ i
+ 1 ];
1551 //attempt to identify a Sequence Terminator in ASK modulated raw wave
1552 bool DetectST ( uint8_t buffer
[], size_t * size
, int * foundclock
) {
1553 size_t bufsize
= * size
;
1554 //need to loop through all samples and identify our clock, look for the ST pattern
1555 uint8_t fndClk
[] = { 8 , 16 , 32 , 40 , 50 , 64 , 128 };
1558 int i
, j
, skip
, start
, end
, low
, high
, minClk
, waveStart
;
1559 bool complete
= false ;
1560 int tmpbuff
[ bufsize
/ 64 ];
1561 int waveLen
[ bufsize
/ 64 ];
1562 size_t testsize
= ( bufsize
< 512 ) ? bufsize
: 512 ;
1565 memset ( tmpbuff
, 0 , sizeof ( tmpbuff
));
1567 if ( getHiLo ( buffer
, testsize
, & high
, & low
, 80 , 80 ) == - 1 ) {
1568 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: just noise detected - quitting" );
1569 return false ; //just noise
1574 // get to first full low to prime loop and skip incomplete first pulse
1575 while (( buffer
[ i
] < high
) && ( i
< bufsize
))
1577 while (( buffer
[ i
] > low
) && ( i
< bufsize
))
1581 // populate tmpbuff buffer with pulse lengths
1582 while ( i
< bufsize
) {
1583 // measure from low to low
1584 while (( buffer
[ i
] > low
) && ( i
< bufsize
))
1587 while (( buffer
[ i
] < high
) && ( i
< bufsize
))
1589 //first high point for this wave
1591 while (( buffer
[ i
] > low
) && ( i
< bufsize
))
1593 if ( j
>= ( bufsize
/ 64 )) {
1596 waveLen
[ j
] = i
- waveStart
; //first high to first low
1597 tmpbuff
[ j
++] = i
- start
;
1598 if ( i
- start
< minClk
&& i
< bufsize
) {
1602 // set clock - might be able to get this externally and remove this work...
1604 for ( uint8_t clkCnt
= 0 ; clkCnt
< 7 ; clkCnt
++) {
1605 tol
= fndClk
[ clkCnt
]/ 8 ;
1606 if ( minClk
>= fndClk
[ clkCnt
]- tol
&& minClk
<= fndClk
[ clkCnt
]+ 1 ) {
1611 // clock not found - ERROR
1613 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: clock not found - quitting" );
1620 // look for Sequence Terminator - should be pulses of clk*(1 or 1.5), clk*2, clk*(1.5 or 2)
1622 for ( i
= 0 ; i
< j
- 4 ; ++ i
) {
1624 if ( tmpbuff
[ i
] >= clk
* 1 - tol
&& tmpbuff
[ i
] <= ( clk
* 2 )+ tol
&& waveLen
[ i
] < clk
+ tol
) { //1 to 2 clocks depending on 2 bits prior
1625 if ( tmpbuff
[ i
+ 1 ] >= clk
* 2 - tol
&& tmpbuff
[ i
+ 1 ] <= clk
* 2 + tol
&& waveLen
[ i
+ 1 ] > clk
* 3 / 2 - tol
) { //2 clocks and wave size is 1 1/2
1626 if ( tmpbuff
[ i
+ 2 ] >= ( clk
* 3 )/ 2 - tol
&& tmpbuff
[ i
+ 2 ] <= clk
* 2 + tol
&& waveLen
[ i
+ 2 ] > clk
- tol
) { //1 1/2 to 2 clocks and at least one full clock wave
1627 if ( tmpbuff
[ i
+ 3 ] >= clk
* 1 - tol
&& tmpbuff
[ i
+ 3 ] <= clk
* 2 + tol
) { //1 to 2 clocks for end of ST + first bit
1635 // first ST not found - ERROR
1637 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: first STT not found - quitting" );
1640 if ( waveLen
[ i
+ 2 ] > clk
* 1 + tol
)
1645 // skip over the remainder of ST
1646 skip
+= clk
* 7 / 2 ; //3.5 clocks from tmpbuff[i] = end of st - also aligns for ending point
1648 // now do it again to find the end
1650 for ( i
+= 3 ; i
< j
- 4 ; ++ i
) {
1652 if ( tmpbuff
[ i
] >= clk
* 1 - tol
&& tmpbuff
[ i
] <= ( clk
* 2 )+ tol
) { //1 to 2 clocks depending on 2 bits prior
1653 if ( tmpbuff
[ i
+ 1 ] >= clk
* 2 - tol
&& tmpbuff
[ i
+ 1 ] <= clk
* 2 + tol
&& waveLen
[ i
+ 1 ] > clk
* 3 / 2 - tol
) { //2 clocks and wave size is 1 1/2
1654 if ( tmpbuff
[ i
+ 2 ] >= ( clk
* 3 )/ 2 - tol
&& tmpbuff
[ i
+ 2 ] <= clk
* 2 + tol
&& waveLen
[ i
+ 2 ] > clk
- tol
) { //1 1/2 to 2 clocks and at least one full clock wave
1655 if ( tmpbuff
[ i
+ 3 ] >= clk
* 1 - tol
&& tmpbuff
[ i
+ 3 ] <= clk
* 2 + tol
) { //1 to 2 clocks for end of ST + first bit
1664 //didn't find second ST - ERROR
1666 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: second STT not found - quitting" );
1669 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: start of data: %d end of data: %d, datalen: %d, clk: %d, bits: %d, phaseoff: %d" , skip
, end
, end
- skip
, clk
, ( end
- skip
)/ clk
, phaseoff
);
1670 //now begin to trim out ST so we can use normal demod cmds
1672 size_t datalen
= end
- start
;
1673 // check validity of datalen (should be even clock increments) - use a tolerance of up to 1/8th a clock
1674 if ( datalen
% clk
> clk
/ 8 ) {
1675 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: datalen not divisible by clk: %u %% %d = %d - quitting" , datalen
, clk
, datalen
% clk
);
1678 // padd the amount off - could be problematic... but shouldn't happen often
1679 datalen
+= datalen
% clk
;
1681 // if datalen is less than one t55xx block - ERROR
1682 if ( datalen
/ clk
< 8 * 4 ) {
1683 if ( g_debugMode
== 2 ) prnt ( "DEBUG STT: datalen is less than 1 full t55xx block - quitting" );
1686 size_t dataloc
= start
;
1689 // warning - overwriting buffer given with raw wave data with ST removed...
1690 while ( dataloc
< bufsize
-( clk
/ 2 ) ) {
1691 //compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part)
1692 if ( buffer
[ dataloc
]< high
&& buffer
[ dataloc
]> low
&& buffer
[ dataloc
+ 3 ]< high
&& buffer
[ dataloc
+ 3 ]> low
) {
1693 for ( i
= 0 ; i
< clk
/ 2 - tol
; ++ i
) {
1694 buffer
[ dataloc
+ i
] = high
+ 5 ;
1697 for ( i
= 0 ; i
< datalen
; ++ i
) {
1698 if ( i
+ newloc
< bufsize
) {
1699 if ( i
+ newloc
< dataloc
)
1700 buffer
[ i
+ newloc
] = buffer
[ dataloc
];
1706 //skip next ST - we just assume it will be there from now on...