]>
Commit | Line | Data |
---|---|---|
1 | //----------------------------------------------------------------------------- | |
2 | // Copyright (C) 2014 | |
3 | // | |
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 | |
6 | // the license. | |
7 | //----------------------------------------------------------------------------- | |
8 | // Low frequency demod/decode commands | |
9 | //----------------------------------------------------------------------------- | |
10 | ||
11 | #include <stdlib.h> | |
12 | #include <string.h> | |
13 | #include "lfdemod.h" | |
14 | ||
15 | ||
16 | uint8_t justNoise(uint8_t *BitStream, size_t size) | |
17 | { | |
18 | static const uint8_t THRESHOLD = 123; | |
19 | //test samples are not just noise | |
20 | uint8_t justNoise1 = 1; | |
21 | for(size_t idx=0; idx < size && justNoise1 ;idx++){ | |
22 | justNoise1 = BitStream[idx] < THRESHOLD; | |
23 | } | |
24 | return justNoise1; | |
25 | } | |
26 | ||
27 | //by marshmellow | |
28 | //get high and low with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise | |
29 | int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo) | |
30 | { | |
31 | *high=0; | |
32 | *low=255; | |
33 | // get high and low thresholds | |
34 | for (int i=0; i < size; i++){ | |
35 | if (BitStream[i] > *high) *high = BitStream[i]; | |
36 | if (BitStream[i] < *low) *low = BitStream[i]; | |
37 | } | |
38 | if (*high < 123) return -1; // just noise | |
39 | *high = (int)(((*high-128)*(((float)fuzzHi)/100))+128); | |
40 | *low = (int)(((*low-128)*(((float)fuzzLo)/100))+128); | |
41 | return 1; | |
42 | } | |
43 | ||
44 | // by marshmellow | |
45 | // pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType | |
46 | // returns 1 if passed | |
47 | uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) | |
48 | { | |
49 | uint8_t ans = 0; | |
50 | for (uint8_t i = 0; i < bitLen; i++){ | |
51 | ans ^= ((bits >> i) & 1); | |
52 | } | |
53 | //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); | |
54 | return (ans == pType); | |
55 | } | |
56 | ||
57 | //by marshmellow | |
58 | //search for given preamble in given BitStream and return startIndex and length | |
59 | uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx) | |
60 | { | |
61 | uint8_t foundCnt=0; | |
62 | for (int idx=0; idx < *size - pLen; idx++){ | |
63 | if (memcmp(BitStream+idx, preamble, pLen) == 0){ | |
64 | //first index found | |
65 | foundCnt++; | |
66 | if (foundCnt == 1){ | |
67 | *startIdx = idx; | |
68 | } | |
69 | if (foundCnt == 2){ | |
70 | *size = idx - *startIdx; | |
71 | return 1; | |
72 | } | |
73 | } | |
74 | } | |
75 | return 0; | |
76 | } | |
77 | ||
78 | ||
79 | //by marshmellow | |
80 | //takes 1s and 0s and searches for EM410x format - output EM ID | |
81 | uint64_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx) | |
82 | { | |
83 | //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future | |
84 | // otherwise could be a void with no arguments | |
85 | //set defaults | |
86 | uint64_t lo=0; | |
87 | uint32_t i = 0; | |
88 | if (BitStream[1]>1){ //allow only 1s and 0s | |
89 | // PrintAndLog("no data found"); | |
90 | return 0; | |
91 | } | |
92 | // 111111111 bit pattern represent start of frame | |
93 | uint8_t preamble[] = {1,1,1,1,1,1,1,1,1}; | |
94 | uint32_t idx = 0; | |
95 | uint32_t parityBits = 0; | |
96 | uint8_t errChk = 0; | |
97 | *startIdx = 0; | |
98 | for (uint8_t extraBitChk=0; extraBitChk<5; extraBitChk++){ | |
99 | errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx); | |
100 | if (errChk == 0) return 0; | |
101 | idx = *startIdx + 9; | |
102 | for (i=0; i<10;i++){ //loop through 10 sets of 5 bits (50-10p = 40 bits) | |
103 | parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5); | |
104 | //check even parity | |
105 | if (parityTest(parityBits, 5, 0) == 0){ | |
106 | //parity failed try next bit (in the case of 1111111111) but last 9 = preamble | |
107 | startIdx++; | |
108 | errChk = 0; | |
109 | break; | |
110 | } | |
111 | for (uint8_t ii=0; ii<4; ii++){ | |
112 | lo = (lo << 1LL) | (BitStream[(i*5)+ii+idx]); | |
113 | } | |
114 | } | |
115 | if (errChk != 0) return lo; | |
116 | //skip last 5 bit parity test for simplicity. | |
117 | // *size = 64; | |
118 | } | |
119 | return 0; | |
120 | } | |
121 | ||
122 | //by marshmellow | |
123 | //takes 2 arguments - clock and invert both as integers | |
124 | //attempts to demodulate ask while decoding manchester | |
125 | //prints binary found and saves in graphbuffer for further commands | |
126 | int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) | |
127 | { | |
128 | int i; | |
129 | int clk2=*clk; | |
130 | *clk=DetectASKClock(BinStream, *size, *clk); //clock default | |
131 | ||
132 | // if autodetected too low then adjust //MAY NEED ADJUSTMENT | |
133 | if (clk2==0 && *clk<8) *clk =64; | |
134 | if (clk2==0 && *clk<32) *clk=32; | |
135 | if (*invert != 0 && *invert != 1) *invert=0; | |
136 | uint32_t initLoopMax = 200; | |
137 | if (initLoopMax > *size) initLoopMax=*size; | |
138 | // Detect high and lows | |
139 | // 25% fuzz in case highs and lows aren't clipped [marshmellow] | |
140 | int high, low, ans; | |
141 | ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); | |
142 | if (ans<1) return -2; //just noise | |
143 | ||
144 | // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); | |
145 | int lastBit = 0; //set first clock check | |
146 | uint32_t bitnum = 0; //output counter | |
147 | int tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave | |
148 | 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 | |
149 | int iii = 0; | |
150 | uint32_t gLen = *size; | |
151 | if (gLen > 3000) gLen=3000; | |
152 | uint8_t errCnt =0; | |
153 | uint32_t bestStart = *size; | |
154 | uint32_t bestErrCnt = (*size/1000); | |
155 | uint32_t maxErr = (*size/1000); | |
156 | // PrintAndLog("DEBUG - lastbit - %d",lastBit); | |
157 | // loop to find first wave that works | |
158 | for (iii=0; iii < gLen; ++iii){ | |
159 | if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){ | |
160 | lastBit=iii-*clk; | |
161 | errCnt=0; | |
162 | // loop through to see if this start location works | |
163 | for (i = iii; i < *size; ++i) { | |
164 | if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ | |
165 | lastBit+=*clk; | |
166 | } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ | |
167 | //low found and we are expecting a bar | |
168 | lastBit+=*clk; | |
169 | } else { | |
170 | //mid value found or no bar supposed to be here | |
171 | if ((i-lastBit)>(*clk+tol)){ | |
172 | //should have hit a high or low based on clock!! | |
173 | ||
174 | //debug | |
175 | //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); | |
176 | ||
177 | errCnt++; | |
178 | lastBit+=*clk;//skip over until hit too many errors | |
179 | if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over | |
180 | } | |
181 | } | |
182 | if ((i-iii) >(400 * *clk)) break; //got plenty of bits | |
183 | } | |
184 | //we got more than 64 good bits and not all errors | |
185 | if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<maxErr)) { | |
186 | //possible good read | |
187 | if (errCnt==0){ | |
188 | bestStart=iii; | |
189 | bestErrCnt=errCnt; | |
190 | break; //great read - finish | |
191 | } | |
192 | if (errCnt<bestErrCnt){ //set this as new best run | |
193 | bestErrCnt=errCnt; | |
194 | bestStart = iii; | |
195 | } | |
196 | } | |
197 | } | |
198 | } | |
199 | if (bestErrCnt<maxErr){ | |
200 | //best run is good enough set to best run and set overwrite BinStream | |
201 | iii=bestStart; | |
202 | lastBit = bestStart - *clk; | |
203 | bitnum=0; | |
204 | for (i = iii; i < *size; ++i) { | |
205 | if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ | |
206 | lastBit += *clk; | |
207 | BinStream[bitnum] = *invert; | |
208 | bitnum++; | |
209 | } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ | |
210 | //low found and we are expecting a bar | |
211 | lastBit+=*clk; | |
212 | BinStream[bitnum] = 1-*invert; | |
213 | bitnum++; | |
214 | } else { | |
215 | //mid value found or no bar supposed to be here | |
216 | if ((i-lastBit)>(*clk+tol)){ | |
217 | //should have hit a high or low based on clock!! | |
218 | ||
219 | //debug | |
220 | //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); | |
221 | if (bitnum > 0){ | |
222 | BinStream[bitnum]=77; | |
223 | bitnum++; | |
224 | } | |
225 | ||
226 | lastBit+=*clk;//skip over error | |
227 | } | |
228 | } | |
229 | if (bitnum >=400) break; | |
230 | } | |
231 | *size=bitnum; | |
232 | } else{ | |
233 | *invert=bestStart; | |
234 | *clk=iii; | |
235 | return -1; | |
236 | } | |
237 | return bestErrCnt; | |
238 | } | |
239 | ||
240 | //by marshmellow | |
241 | //encode binary data into binary manchester | |
242 | int ManchesterEncode(uint8_t *BitStream, size_t size) | |
243 | { | |
244 | size_t modIdx=20000, i=0; | |
245 | if (size>modIdx) return -1; | |
246 | for (size_t idx=0; idx < size; idx++){ | |
247 | BitStream[idx+modIdx++] = BitStream[idx]; | |
248 | BitStream[idx+modIdx++] = BitStream[idx]^1; | |
249 | } | |
250 | for (; i<(size*2); i++){ | |
251 | BitStream[i] = BitStream[i+20000]; | |
252 | } | |
253 | return i; | |
254 | } | |
255 | ||
256 | //by marshmellow | |
257 | //take 10 and 01 and manchester decode | |
258 | //run through 2 times and take least errCnt | |
259 | int manrawdecode(uint8_t * BitStream, size_t *size) | |
260 | { | |
261 | int bitnum=0; | |
262 | int errCnt =0; | |
263 | int i=1; | |
264 | int bestErr = 1000; | |
265 | int bestRun = 0; | |
266 | int ii=1; | |
267 | for (ii=1;ii<3;++ii){ | |
268 | i=1; | |
269 | for (i=i+ii;i<*size-2;i+=2){ | |
270 | if(BitStream[i]==1 && (BitStream[i+1]==0)){ | |
271 | } else if((BitStream[i]==0)&& BitStream[i+1]==1){ | |
272 | } else { | |
273 | errCnt++; | |
274 | } | |
275 | if(bitnum>300) break; | |
276 | } | |
277 | if (bestErr>errCnt){ | |
278 | bestErr=errCnt; | |
279 | bestRun=ii; | |
280 | } | |
281 | errCnt=0; | |
282 | } | |
283 | errCnt=bestErr; | |
284 | if (errCnt<20){ | |
285 | ii=bestRun; | |
286 | i=1; | |
287 | for (i=i+ii;i < *size-2;i+=2){ | |
288 | if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ | |
289 | BitStream[bitnum++]=0; | |
290 | } else if((BitStream[i] == 0) && BitStream[i+1] == 1){ | |
291 | BitStream[bitnum++]=1; | |
292 | } else { | |
293 | BitStream[bitnum++]=77; | |
294 | //errCnt++; | |
295 | } | |
296 | if(bitnum>300) break; | |
297 | } | |
298 | *size=bitnum; | |
299 | } | |
300 | return errCnt; | |
301 | } | |
302 | ||
303 | //by marshmellow | |
304 | //take 01 or 10 = 0 and 11 or 00 = 1 | |
305 | int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) | |
306 | { | |
307 | uint8_t bitnum=0; | |
308 | uint32_t errCnt =0; | |
309 | uint32_t i; | |
310 | i=offset; | |
311 | for (;i<*size-2; i+=2){ | |
312 | if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){ | |
313 | BitStream[bitnum++]=1^invert; | |
314 | } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){ | |
315 | BitStream[bitnum++]=invert; | |
316 | } else { | |
317 | BitStream[bitnum++]=77; | |
318 | errCnt++; | |
319 | } | |
320 | if(bitnum>250) break; | |
321 | } | |
322 | *size=bitnum; | |
323 | return errCnt; | |
324 | } | |
325 | ||
326 | //by marshmellow | |
327 | //takes 2 arguments - clock and invert both as integers | |
328 | //attempts to demodulate ask only | |
329 | //prints binary found and saves in graphbuffer for further commands | |
330 | int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) | |
331 | { | |
332 | uint32_t i; | |
333 | // int invert=0; //invert default | |
334 | int clk2 = *clk; | |
335 | *clk=DetectASKClock(BinStream, *size, *clk); //clock default | |
336 | //uint8_t BitStream[502] = {0}; | |
337 | ||
338 | //HACK: if clock not detected correctly - default | |
339 | if (clk2==0 && *clk<8) *clk =64; | |
340 | if (clk2==0 && *clk<32 && clk2==0) *clk=32; | |
341 | if (*invert != 0 && *invert != 1) *invert =0; | |
342 | uint32_t initLoopMax = 200; | |
343 | if (initLoopMax > *size) initLoopMax=*size; | |
344 | // Detect high and lows | |
345 | //25% fuzz in case highs and lows aren't clipped [marshmellow] | |
346 | int high, low, ans; | |
347 | ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); | |
348 | if (ans<1) return -2; //just noise | |
349 | ||
350 | //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); | |
351 | int lastBit = 0; //set first clock check | |
352 | uint32_t bitnum = 0; //output counter | |
353 | uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock | |
354 | // if they fall + or - this value + clock from last valid wave | |
355 | if (*clk == 32) tol=1; //clock tolerance may not be needed anymore currently set to | |
356 | // + or - 1 but could be increased for poor waves or removed entirely | |
357 | uint32_t iii = 0; | |
358 | uint32_t gLen = *size; | |
359 | if (gLen > 500) gLen=500; | |
360 | uint8_t errCnt =0; | |
361 | uint32_t bestStart = *size; | |
362 | uint32_t bestErrCnt = (*size/1000); | |
363 | uint32_t maxErr = bestErrCnt; | |
364 | uint8_t midBit=0; | |
365 | //PrintAndLog("DEBUG - lastbit - %d",lastBit); | |
366 | //loop to find first wave that works | |
367 | for (iii=0; iii < gLen; ++iii){ | |
368 | if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){ | |
369 | lastBit=iii-*clk; | |
370 | //loop through to see if this start location works | |
371 | for (i = iii; i < *size; ++i) { | |
372 | if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ | |
373 | lastBit+=*clk; | |
374 | midBit=0; | |
375 | } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ | |
376 | //low found and we are expecting a bar | |
377 | lastBit+=*clk; | |
378 | midBit=0; | |
379 | } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ | |
380 | //mid bar? | |
381 | midBit=1; | |
382 | } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ | |
383 | //mid bar? | |
384 | midBit=1; | |
385 | } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ | |
386 | //no mid bar found | |
387 | midBit=1; | |
388 | } else { | |
389 | //mid value found or no bar supposed to be here | |
390 | ||
391 | if ((i-lastBit)>(*clk+tol)){ | |
392 | //should have hit a high or low based on clock!! | |
393 | //debug | |
394 | //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); | |
395 | ||
396 | errCnt++; | |
397 | lastBit+=*clk;//skip over until hit too many errors | |
398 | if (errCnt > ((*size/1000))){ //allow 1 error for every 1000 samples else start over | |
399 | errCnt=0; | |
400 | break; | |
401 | } | |
402 | } | |
403 | } | |
404 | if ((i-iii)>(500 * *clk)) break; //got enough bits | |
405 | } | |
406 | //we got more than 64 good bits and not all errors | |
407 | if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<(*size/1000))) { | |
408 | //possible good read | |
409 | if (errCnt==0){ | |
410 | bestStart=iii; | |
411 | bestErrCnt=errCnt; | |
412 | break; //great read - finish | |
413 | } | |
414 | if (errCnt<bestErrCnt){ //set this as new best run | |
415 | bestErrCnt=errCnt; | |
416 | bestStart = iii; | |
417 | } | |
418 | } | |
419 | } | |
420 | } | |
421 | if (bestErrCnt<maxErr){ | |
422 | //best run is good enough - set to best run and overwrite BinStream | |
423 | iii=bestStart; | |
424 | lastBit = bestStart - *clk; | |
425 | bitnum=0; | |
426 | for (i = iii; i < *size; ++i) { | |
427 | if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ | |
428 | lastBit += *clk; | |
429 | BinStream[bitnum] = *invert; | |
430 | bitnum++; | |
431 | midBit=0; | |
432 | } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ | |
433 | //low found and we are expecting a bar | |
434 | lastBit+=*clk; | |
435 | BinStream[bitnum] = 1-*invert; | |
436 | bitnum++; | |
437 | midBit=0; | |
438 | } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ | |
439 | //mid bar? | |
440 | midBit=1; | |
441 | BinStream[bitnum] = 1 - *invert; | |
442 | bitnum++; | |
443 | } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ | |
444 | //mid bar? | |
445 | midBit=1; | |
446 | BinStream[bitnum] = *invert; | |
447 | bitnum++; | |
448 | } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ | |
449 | //no mid bar found | |
450 | midBit=1; | |
451 | if (bitnum!=0) BinStream[bitnum] = BinStream[bitnum-1]; | |
452 | bitnum++; | |
453 | ||
454 | } else { | |
455 | //mid value found or no bar supposed to be here | |
456 | if ((i-lastBit)>(*clk+tol)){ | |
457 | //should have hit a high or low based on clock!! | |
458 | ||
459 | //debug | |
460 | //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); | |
461 | if (bitnum > 0){ | |
462 | BinStream[bitnum]=77; | |
463 | bitnum++; | |
464 | } | |
465 | ||
466 | lastBit+=*clk;//skip over error | |
467 | } | |
468 | } | |
469 | if (bitnum >=400) break; | |
470 | } | |
471 | *size=bitnum; | |
472 | } else{ | |
473 | *invert=bestStart; | |
474 | *clk=iii; | |
475 | return -1; | |
476 | } | |
477 | return bestErrCnt; | |
478 | } | |
479 | //translate wave to 11111100000 (1 for each short wave 0 for each long wave) | |
480 | size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) | |
481 | { | |
482 | uint32_t last_transition = 0; | |
483 | uint32_t idx = 1; | |
484 | //uint32_t maxVal=0; | |
485 | if (fchigh==0) fchigh=10; | |
486 | if (fclow==0) fclow=8; | |
487 | //set the threshold close to 0 (graph) or 128 std to avoid static | |
488 | uint8_t threshold_value = 123; | |
489 | ||
490 | // sync to first lo-hi transition, and threshold | |
491 | ||
492 | // Need to threshold first sample | |
493 | ||
494 | if(dest[0] < threshold_value) dest[0] = 0; | |
495 | else dest[0] = 1; | |
496 | ||
497 | size_t numBits = 0; | |
498 | // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8) | |
499 | // or 10 (fc/10) cycles but in practice due to noise etc we may end up with with anywhere | |
500 | // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10 | |
501 | for(idx = 1; idx < size; idx++) { | |
502 | // threshold current value | |
503 | ||
504 | if (dest[idx] < threshold_value) dest[idx] = 0; | |
505 | else dest[idx] = 1; | |
506 | ||
507 | // Check for 0->1 transition | |
508 | if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition | |
509 | if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise | |
510 | //do nothing with extra garbage | |
511 | } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves | |
512 | dest[numBits]=1; | |
513 | } else { //9+ = 10 waves | |
514 | dest[numBits]=0; | |
515 | } | |
516 | last_transition = idx; | |
517 | numBits++; | |
518 | } | |
519 | } | |
520 | return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0 | |
521 | } | |
522 | ||
523 | uint32_t myround2(float f) | |
524 | { | |
525 | if (f >= 2000) return 2000;//something bad happened | |
526 | return (uint32_t) (f + (float)0.5); | |
527 | } | |
528 | ||
529 | //translate 11111100000 to 10 | |
530 | size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, | |
531 | uint8_t invert, uint8_t fchigh, uint8_t fclow) | |
532 | { | |
533 | uint8_t lastval=dest[0]; | |
534 | uint32_t idx=0; | |
535 | size_t numBits=0; | |
536 | uint32_t n=1; | |
537 | ||
538 | for( idx=1; idx < size; idx++) { | |
539 | ||
540 | if (dest[idx]==lastval) { | |
541 | n++; | |
542 | continue; | |
543 | } | |
544 | //if lastval was 1, we have a 1->0 crossing | |
545 | if ( dest[idx-1]==1 ) { | |
546 | n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); | |
547 | } else {// 0->1 crossing | |
548 | n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor | |
549 | } | |
550 | if (n == 0) n = 1; | |
551 | ||
552 | if(n < maxConsequtiveBits) //Consecutive | |
553 | { | |
554 | if(invert==0){ //invert bits | |
555 | memset(dest+numBits, dest[idx-1] , n); | |
556 | }else{ | |
557 | memset(dest+numBits, dest[idx-1]^1 , n); | |
558 | } | |
559 | numBits += n; | |
560 | } | |
561 | n=0; | |
562 | lastval=dest[idx]; | |
563 | }//end for | |
564 | return numBits; | |
565 | } | |
566 | //by marshmellow (from holiman's base) | |
567 | // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod) | |
568 | int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) | |
569 | { | |
570 | // FSK demodulator | |
571 | size = fsk_wave_demod(dest, size, fchigh, fclow); | |
572 | size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow); | |
573 | return size; | |
574 | } | |
575 | ||
576 | // loop to get raw HID waveform then FSK demodulate the TAG ID from it | |
577 | int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) | |
578 | { | |
579 | if (justNoise(dest, *size)) return -1; | |
580 | ||
581 | size_t numStart=0, size2=*size, startIdx=0; | |
582 | // FSK demodulator | |
583 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a | |
584 | if (*size < 96) return -2; | |
585 | // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 | |
586 | uint8_t preamble[] = {0,0,0,1,1,1,0,1}; | |
587 | // find bitstring in array | |
588 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
589 | if (errChk == 0) return -3; //preamble not found | |
590 | ||
591 | numStart = startIdx + sizeof(preamble); | |
592 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
593 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
594 | if (dest[idx] == dest[idx+1]){ | |
595 | return -4; //not manchester data | |
596 | } | |
597 | *hi2 = (*hi2<<1)|(*hi>>31); | |
598 | *hi = (*hi<<1)|(*lo>>31); | |
599 | //Then, shift in a 0 or one into low | |
600 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
601 | *lo=(*lo<<1)|1; | |
602 | else // 0 1 | |
603 | *lo=(*lo<<1)|0; | |
604 | } | |
605 | return (int)startIdx; | |
606 | } | |
607 | ||
608 | // loop to get raw paradox waveform then FSK demodulate the TAG ID from it | |
609 | int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) | |
610 | { | |
611 | if (justNoise(dest, *size)) return -1; | |
612 | ||
613 | size_t numStart=0, size2=*size, startIdx=0; | |
614 | // FSK demodulator | |
615 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a | |
616 | if (*size < 96) return -2; | |
617 | ||
618 | // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 | |
619 | uint8_t preamble[] = {0,0,0,0,1,1,1,1}; | |
620 | ||
621 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
622 | if (errChk == 0) return -3; //preamble not found | |
623 | ||
624 | numStart = startIdx + sizeof(preamble); | |
625 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
626 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
627 | if (dest[idx] == dest[idx+1]) | |
628 | return -4; //not manchester data | |
629 | *hi2 = (*hi2<<1)|(*hi>>31); | |
630 | *hi = (*hi<<1)|(*lo>>31); | |
631 | //Then, shift in a 0 or one into low | |
632 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
633 | *lo=(*lo<<1)|1; | |
634 | else // 0 1 | |
635 | *lo=(*lo<<1)|0; | |
636 | } | |
637 | return (int)startIdx; | |
638 | } | |
639 | ||
640 | uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) | |
641 | { | |
642 | uint32_t num = 0; | |
643 | for(int i = 0 ; i < numbits ; i++) | |
644 | { | |
645 | num = (num << 1) | (*src); | |
646 | src++; | |
647 | } | |
648 | return num; | |
649 | } | |
650 | ||
651 | int IOdemodFSK(uint8_t *dest, size_t size) | |
652 | { | |
653 | if (justNoise(dest, size)) return -1; | |
654 | //make sure buffer has data | |
655 | if (size < 66*64) return -2; | |
656 | // FSK demodulator | |
657 | size = fskdemod(dest, size, 64, 1, 10, 8); // FSK2a RF/64 | |
658 | if (size < 65) return -3; //did we get a good demod? | |
659 | //Index map | |
660 | //0 10 20 30 40 50 60 | |
661 | //| | | | | | | | |
662 | //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23 | |
663 | //----------------------------------------------------------------------------- | |
664 | //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11 | |
665 | // | |
666 | //XSF(version)facility:codeone+codetwo | |
667 | //Handle the data | |
668 | size_t startIdx = 0; | |
669 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1}; | |
670 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx); | |
671 | if (errChk == 0) return -4; //preamble not found | |
672 | ||
673 | if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){ | |
674 | //confirmed proper separator bits found | |
675 | //return start position | |
676 | return (int) startIdx; | |
677 | } | |
678 | return -5; | |
679 | } | |
680 | ||
681 | // by marshmellow | |
682 | // takes a array of binary values, start position, length of bits per parity (includes parity bit), | |
683 | // Parity Type (1 for odd 0 for even), and binary Length (length to run) | |
684 | size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) | |
685 | { | |
686 | uint32_t parityWd = 0; | |
687 | size_t j = 0, bitCnt = 0; | |
688 | for (int word = 0; word < (bLen); word+=pLen){ | |
689 | for (int bit=0; bit < pLen; bit++){ | |
690 | parityWd = (parityWd << 1) | BitStream[startIdx+word+bit]; | |
691 | BitStream[j++] = (BitStream[startIdx+word+bit]); | |
692 | } | |
693 | j--; | |
694 | // if parity fails then return 0 | |
695 | if (parityTest(parityWd, pLen, pType) == 0) return -1; | |
696 | bitCnt+=(pLen-1); | |
697 | parityWd = 0; | |
698 | } | |
699 | // if we got here then all the parities passed | |
700 | //return ID start index and size | |
701 | return bitCnt; | |
702 | } | |
703 | ||
704 | // by marshmellow | |
705 | // FSK Demod then try to locate an AWID ID | |
706 | int AWIDdemodFSK(uint8_t *dest, size_t *size) | |
707 | { | |
708 | //make sure buffer has enough data | |
709 | if (*size < 96*50) return -1; | |
710 | ||
711 | if (justNoise(dest, *size)) return -2; | |
712 | ||
713 | // FSK demodulator | |
714 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 | |
715 | if (*size < 96) return -3; //did we get a good demod? | |
716 | ||
717 | uint8_t preamble[] = {0,0,0,0,0,0,0,1}; | |
718 | size_t startIdx = 0; | |
719 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
720 | if (errChk == 0) return -4; //preamble not found | |
721 | if (*size != 96) return -5; | |
722 | return (int)startIdx; | |
723 | } | |
724 | ||
725 | // by marshmellow | |
726 | // FSK Demod then try to locate an Farpointe Data (pyramid) ID | |
727 | int PyramiddemodFSK(uint8_t *dest, size_t *size) | |
728 | { | |
729 | //make sure buffer has data | |
730 | if (*size < 128*50) return -5; | |
731 | ||
732 | //test samples are not just noise | |
733 | if (justNoise(dest, *size)) return -1; | |
734 | ||
735 | // FSK demodulator | |
736 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 | |
737 | if (*size < 128) return -2; //did we get a good demod? | |
738 | ||
739 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; | |
740 | size_t startIdx = 0; | |
741 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
742 | if (errChk == 0) return -4; //preamble not found | |
743 | if (*size != 128) return -3; | |
744 | return (int)startIdx; | |
745 | } | |
746 | ||
747 | // by marshmellow | |
748 | // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping) | |
749 | // maybe somehow adjust peak trimming value based on samples to fix? | |
750 | int DetectASKClock(uint8_t dest[], size_t size, int clock) | |
751 | { | |
752 | int i=0; | |
753 | int clk[]={8,16,32,40,50,64,100,128,256}; | |
754 | int loopCnt = 256; //don't need to loop through entire array... | |
755 | if (size<loopCnt) loopCnt = size; | |
756 | ||
757 | //if we already have a valid clock quit | |
758 | ||
759 | for (;i<8;++i) | |
760 | if (clk[i] == clock) return clock; | |
761 | ||
762 | //get high and low peak | |
763 | int peak, low; | |
764 | getHiLo(dest, loopCnt, &peak, &low, 75, 75); | |
765 | ||
766 | int ii; | |
767 | int clkCnt; | |
768 | int tol = 0; | |
769 | int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; | |
770 | int errCnt=0; | |
771 | //test each valid clock from smallest to greatest to see which lines up | |
772 | for(clkCnt=0; clkCnt < 8; ++clkCnt){ | |
773 | if (clk[clkCnt] == 32){ | |
774 | tol=1; | |
775 | }else{ | |
776 | tol=0; | |
777 | } | |
778 | bestErr[clkCnt]=1000; | |
779 | //try lining up the peaks by moving starting point (try first 256) | |
780 | for (ii=0; ii < loopCnt; ++ii){ | |
781 | if ((dest[ii] >= peak) || (dest[ii] <= low)){ | |
782 | errCnt=0; | |
783 | // now that we have the first one lined up test rest of wave array | |
784 | for (i=0; i<((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ | |
785 | if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ | |
786 | }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ | |
787 | }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ | |
788 | }else{ //error no peak detected | |
789 | errCnt++; | |
790 | } | |
791 | } | |
792 | //if we found no errors then we can stop here | |
793 | // this is correct one - return this clock | |
794 | //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i); | |
795 | if(errCnt==0 && clkCnt<6) return clk[clkCnt]; | |
796 | //if we found errors see if it is lowest so far and save it as best run | |
797 | if(errCnt<bestErr[clkCnt]) bestErr[clkCnt]=errCnt; | |
798 | } | |
799 | } | |
800 | } | |
801 | uint8_t iii=0; | |
802 | uint8_t best=0; | |
803 | for (iii=0; iii<8; ++iii){ | |
804 | if (bestErr[iii]<bestErr[best]){ | |
805 | if (bestErr[iii]==0) bestErr[iii]=1; | |
806 | // current best bit to error ratio vs new bit to error ratio | |
807 | if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){ | |
808 | best = iii; | |
809 | } | |
810 | } | |
811 | } | |
812 | return clk[best]; | |
813 | } | |
814 | ||
815 | //by marshmellow | |
816 | //detect psk clock by reading #peaks vs no peaks(or errors) | |
817 | int DetectpskNRZClock(uint8_t dest[], size_t size, int clock) | |
818 | { | |
819 | int i=0; | |
820 | int clk[]={16,32,40,50,64,100,128,256}; | |
821 | int loopCnt = 2048; //don't need to loop through entire array... | |
822 | if (size<loopCnt) loopCnt = size; | |
823 | ||
824 | //if we already have a valid clock quit | |
825 | for (; i < 7; ++i) | |
826 | if (clk[i] == clock) return clock; | |
827 | ||
828 | //get high and low peak | |
829 | int peak, low; | |
830 | getHiLo(dest, loopCnt, &peak, &low, 75, 75); | |
831 | ||
832 | //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low); | |
833 | int ii; | |
834 | uint8_t clkCnt; | |
835 | uint8_t tol = 0; | |
836 | int peakcnt=0; | |
837 | int errCnt=0; | |
838 | int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000}; | |
839 | int peaksdet[]={0,0,0,0,0,0,0,0}; | |
840 | //test each valid clock from smallest to greatest to see which lines up | |
841 | for(clkCnt=0; clkCnt < 7; ++clkCnt){ | |
842 | if (clk[clkCnt] <= 32){ | |
843 | tol=1; | |
844 | }else{ | |
845 | tol=0; | |
846 | } | |
847 | //try lining up the peaks by moving starting point (try first 256) | |
848 | for (ii=0; ii< loopCnt; ++ii){ | |
849 | if ((dest[ii] >= peak) || (dest[ii] <= low)){ | |
850 | errCnt=0; | |
851 | peakcnt=0; | |
852 | // now that we have the first one lined up test rest of wave array | |
853 | for (i=0; i < ((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ | |
854 | if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ | |
855 | peakcnt++; | |
856 | }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ | |
857 | peakcnt++; | |
858 | }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ | |
859 | peakcnt++; | |
860 | }else{ //error no peak detected | |
861 | errCnt++; | |
862 | } | |
863 | } | |
864 | if(peakcnt>peaksdet[clkCnt]) { | |
865 | peaksdet[clkCnt]=peakcnt; | |
866 | bestErr[clkCnt]=errCnt; | |
867 | } | |
868 | } | |
869 | } | |
870 | } | |
871 | int iii=0; | |
872 | int best=0; | |
873 | //int ratio2; //debug | |
874 | int ratio; | |
875 | //int bits; | |
876 | for (iii=0; iii < 7; ++iii){ | |
877 | ratio=1000; | |
878 | //ratio2=1000; //debug | |
879 | //bits=size/clk[iii]; //debug | |
880 | if (peaksdet[iii] > 0){ | |
881 | ratio=bestErr[iii]/peaksdet[iii]; | |
882 | if (((bestErr[best]/peaksdet[best]) > (ratio)+1)){ | |
883 | best = iii; | |
884 | } | |
885 | //ratio2=bits/peaksdet[iii]; //debug | |
886 | } | |
887 | //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d, ratio: %d, bits: %d, peakbitr: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best],ratio, bits,ratio2); | |
888 | } | |
889 | return clk[best]; | |
890 | } | |
891 | ||
892 | // by marshmellow (attempt to get rid of high immediately after a low) | |
893 | void pskCleanWave(uint8_t *BitStream, size_t size) | |
894 | { | |
895 | int i; | |
896 | int gap = 4; | |
897 | int newLow=0; | |
898 | int newHigh=0; | |
899 | int high, low; | |
900 | getHiLo(BitStream, size, &high, &low, 80, 90); | |
901 | ||
902 | for (i=0; i < size; ++i){ | |
903 | if (newLow == 1){ | |
904 | if (BitStream[i]>low){ | |
905 | BitStream[i]=low+8; | |
906 | gap--; | |
907 | } | |
908 | if (gap == 0){ | |
909 | newLow=0; | |
910 | gap=4; | |
911 | } | |
912 | }else if (newHigh == 1){ | |
913 | if (BitStream[i]<high){ | |
914 | BitStream[i]=high-8; | |
915 | gap--; | |
916 | } | |
917 | if (gap == 0){ | |
918 | newHigh=0; | |
919 | gap=4; | |
920 | } | |
921 | } | |
922 | if (BitStream[i] <= low) newLow=1; | |
923 | if (BitStream[i] >= high) newHigh=1; | |
924 | } | |
925 | return; | |
926 | } | |
927 | ||
928 | // by marshmellow | |
929 | // convert psk1 demod to psk2 demod | |
930 | // only transition waves are 1s | |
931 | void psk1TOpsk2(uint8_t *BitStream, size_t size) | |
932 | { | |
933 | size_t i=1; | |
934 | uint8_t lastBit=BitStream[0]; | |
935 | for (; i<size; i++){ | |
936 | if (lastBit!=BitStream[i]){ | |
937 | lastBit=BitStream[i]; | |
938 | BitStream[i]=1; | |
939 | } else { | |
940 | BitStream[i]=0; | |
941 | } | |
942 | } | |
943 | return; | |
944 | } | |
945 | ||
946 | // redesigned by marshmellow adjusted from existing decode functions | |
947 | // indala id decoding - only tested on 26 bit tags, but attempted to make it work for more | |
948 | int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert) | |
949 | { | |
950 | //26 bit 40134 format (don't know other formats) | |
951 | int i; | |
952 | int long_wait=29;//29 leading zeros in format | |
953 | int start; | |
954 | int first = 0; | |
955 | int first2 = 0; | |
956 | int bitCnt = 0; | |
957 | int ii; | |
958 | // Finding the start of a UID | |
959 | for (start = 0; start <= *size - 250; start++) { | |
960 | first = bitStream[start]; | |
961 | for (i = start; i < start + long_wait; i++) { | |
962 | if (bitStream[i] != first) { | |
963 | break; | |
964 | } | |
965 | } | |
966 | if (i == (start + long_wait)) { | |
967 | break; | |
968 | } | |
969 | } | |
970 | if (start == *size - 250 + 1) { | |
971 | // did not find start sequence | |
972 | return -1; | |
973 | } | |
974 | // Inverting signal if needed | |
975 | if (first == 1) { | |
976 | for (i = start; i < *size; i++) { | |
977 | bitStream[i] = !bitStream[i]; | |
978 | } | |
979 | *invert = 1; | |
980 | }else *invert=0; | |
981 | ||
982 | int iii; | |
983 | //found start once now test length by finding next one | |
984 | for (ii=start+29; ii <= *size - 250; ii++) { | |
985 | first2 = bitStream[ii]; | |
986 | for (iii = ii; iii < ii + long_wait; iii++) { | |
987 | if (bitStream[iii] != first2) { | |
988 | break; | |
989 | } | |
990 | } | |
991 | if (iii == (ii + long_wait)) { | |
992 | break; | |
993 | } | |
994 | } | |
995 | if (ii== *size - 250 + 1){ | |
996 | // did not find second start sequence | |
997 | return -2; | |
998 | } | |
999 | bitCnt=ii-start; | |
1000 | ||
1001 | // Dumping UID | |
1002 | i = start; | |
1003 | for (ii = 0; ii < bitCnt; ii++) { | |
1004 | bitStream[ii] = bitStream[i++]; | |
1005 | } | |
1006 | *size=bitCnt; | |
1007 | return 1; | |
1008 | } | |
1009 | ||
1010 | // by marshmellow - demodulate PSK1 wave or NRZ wave (both similar enough) | |
1011 | // peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak | |
1012 | int pskNRZrawDemod(uint8_t *dest, size_t *size, int *clk, int *invert) | |
1013 | { | |
1014 | if (justNoise(dest, *size)) return -1; | |
1015 | pskCleanWave(dest,*size); | |
1016 | int clk2 = DetectpskNRZClock(dest, *size, *clk); | |
1017 | *clk=clk2; | |
1018 | uint32_t i; | |
1019 | int high, low, ans; | |
1020 | ans = getHiLo(dest, 1260, &high, &low, 75, 80); //25% fuzz on high 20% fuzz on low | |
1021 | if (ans<1) return -2; //just noise | |
1022 | uint32_t gLen = *size; | |
1023 | //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); | |
1024 | int lastBit = 0; //set first clock check | |
1025 | uint32_t bitnum = 0; //output counter | |
1026 | uint8_t tol = 1; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave | |
1027 | if (*clk==32) tol = 2; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely | |
1028 | uint32_t iii = 0; | |
1029 | uint8_t errCnt =0; | |
1030 | uint32_t bestStart = *size; | |
1031 | uint32_t maxErr = (*size/1000); | |
1032 | uint32_t bestErrCnt = maxErr; | |
1033 | uint8_t curBit=0; | |
1034 | uint8_t bitHigh=0; | |
1035 | uint8_t ignorewin=*clk/8; | |
1036 | //PrintAndLog("DEBUG - lastbit - %d",lastBit); | |
1037 | //loop to find first wave that works - align to clock | |
1038 | for (iii=0; iii < gLen; ++iii){ | |
1039 | if ((dest[iii]>=high) || (dest[iii]<=low)){ | |
1040 | lastBit=iii-*clk; | |
1041 | //loop through to see if this start location works | |
1042 | for (i = iii; i < *size; ++i) { | |
1043 | //if we found a high bar and we are at a clock bit | |
1044 | if ((dest[i]>=high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ | |
1045 | bitHigh=1; | |
1046 | lastBit+=*clk; | |
1047 | ignorewin=*clk/8; | |
1048 | bitnum++; | |
1049 | //else if low bar found and we are at a clock point | |
1050 | }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ | |
1051 | bitHigh=1; | |
1052 | lastBit+=*clk; | |
1053 | ignorewin=*clk/8; | |
1054 | bitnum++; | |
1055 | //else if no bars found | |
1056 | }else if(dest[i] < high && dest[i] > low) { | |
1057 | if (ignorewin==0){ | |
1058 | bitHigh=0; | |
1059 | }else ignorewin--; | |
1060 | //if we are past a clock point | |
1061 | if (i >= lastBit+*clk+tol){ //clock val | |
1062 | lastBit+=*clk; | |
1063 | bitnum++; | |
1064 | } | |
1065 | //else if bar found but we are not at a clock bit and we did not just have a clock bit | |
1066 | }else if ((dest[i]>=high || dest[i]<=low) && (i<lastBit+*clk-tol || i>lastBit+*clk+tol) && (bitHigh==0)){ | |
1067 | //error bar found no clock... | |
1068 | errCnt++; | |
1069 | } | |
1070 | if (bitnum>=1000) break; | |
1071 | } | |
1072 | //we got more than 64 good bits and not all errors | |
1073 | if ((bitnum > (64+errCnt)) && (errCnt < (maxErr))) { | |
1074 | //possible good read | |
1075 | if (errCnt == 0){ | |
1076 | bestStart = iii; | |
1077 | bestErrCnt = errCnt; | |
1078 | break; //great read - finish | |
1079 | } | |
1080 | if (errCnt < bestErrCnt){ //set this as new best run | |
1081 | bestErrCnt = errCnt; | |
1082 | bestStart = iii; | |
1083 | } | |
1084 | } | |
1085 | } | |
1086 | } | |
1087 | if (bestErrCnt < maxErr){ | |
1088 | //best run is good enough set to best run and set overwrite BinStream | |
1089 | iii=bestStart; | |
1090 | lastBit=bestStart-*clk; | |
1091 | bitnum=0; | |
1092 | for (i = iii; i < *size; ++i) { | |
1093 | //if we found a high bar and we are at a clock bit | |
1094 | if ((dest[i] >= high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ | |
1095 | bitHigh=1; | |
1096 | lastBit+=*clk; | |
1097 | curBit=1-*invert; | |
1098 | dest[bitnum]=curBit; | |
1099 | ignorewin=*clk/8; | |
1100 | bitnum++; | |
1101 | //else if low bar found and we are at a clock point | |
1102 | }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ | |
1103 | bitHigh=1; | |
1104 | lastBit+=*clk; | |
1105 | curBit=*invert; | |
1106 | dest[bitnum]=curBit; | |
1107 | ignorewin=*clk/8; | |
1108 | bitnum++; | |
1109 | //else if no bars found | |
1110 | }else if(dest[i]<high && dest[i]>low) { | |
1111 | if (ignorewin==0){ | |
1112 | bitHigh=0; | |
1113 | }else ignorewin--; | |
1114 | //if we are past a clock point | |
1115 | if (i>=lastBit+*clk+tol){ //clock val | |
1116 | lastBit+=*clk; | |
1117 | dest[bitnum]=curBit; | |
1118 | bitnum++; | |
1119 | } | |
1120 | //else if bar found but we are not at a clock bit and we did not just have a clock bit | |
1121 | }else if ((dest[i]>=high || dest[i]<=low) && ((i<lastBit+*clk-tol) || (i>lastBit+*clk+tol)) && (bitHigh==0)){ | |
1122 | //error bar found no clock... | |
1123 | bitHigh=1; | |
1124 | dest[bitnum]=77; | |
1125 | bitnum++; | |
1126 | errCnt++; | |
1127 | } | |
1128 | if (bitnum >=1000) break; | |
1129 | } | |
1130 | *size=bitnum; | |
1131 | } else{ | |
1132 | *size=bitnum; | |
1133 | *clk=bestStart; | |
1134 | return -1; | |
1135 | } | |
1136 | ||
1137 | if (bitnum>16){ | |
1138 | *size=bitnum; | |
1139 | } else return -1; | |
1140 | return errCnt; | |
1141 | } | |
1142 | ||
1143 | //by marshmellow | |
1144 | //detects the bit clock for FSK given the high and low Field Clocks | |
1145 | uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) | |
1146 | { | |
1147 | uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; | |
1148 | uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1149 | uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1150 | uint8_t rfLensFnd = 0; | |
1151 | uint8_t lastFCcnt=0; | |
1152 | uint32_t fcCounter = 0; | |
1153 | uint16_t rfCounter = 0; | |
1154 | uint8_t firstBitFnd = 0; | |
1155 | size_t i; | |
1156 | ||
1157 | uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); | |
1158 | rfLensFnd=0; | |
1159 | fcCounter=0; | |
1160 | rfCounter=0; | |
1161 | firstBitFnd=0; | |
1162 | //PrintAndLog("DEBUG: fcTol: %d",fcTol); | |
1163 | // prime i to first up transition | |
1164 | for (i = 1; i < size-1; i++) | |
1165 | if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) | |
1166 | break; | |
1167 | ||
1168 | for (; i < size-1; i++){ | |
1169 | if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){ | |
1170 | // new peak | |
1171 | fcCounter++; | |
1172 | rfCounter++; | |
1173 | // if we got less than the small fc + tolerance then set it to the small fc | |
1174 | if (fcCounter < fcLow+fcTol) | |
1175 | fcCounter = fcLow; | |
1176 | else //set it to the large fc | |
1177 | fcCounter = fcHigh; | |
1178 | ||
1179 | //look for bit clock (rf/xx) | |
1180 | if ((fcCounter<lastFCcnt || fcCounter>lastFCcnt)){ | |
1181 | //not the same size as the last wave - start of new bit sequence | |
1182 | ||
1183 | if (firstBitFnd>1){ //skip first wave change - probably not a complete bit | |
1184 | for (int ii=0; ii<15; ii++){ | |
1185 | if (rfLens[ii]==rfCounter){ | |
1186 | rfCnts[ii]++; | |
1187 | rfCounter=0; | |
1188 | break; | |
1189 | } | |
1190 | } | |
1191 | if (rfCounter>0 && rfLensFnd<15){ | |
1192 | //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); | |
1193 | rfCnts[rfLensFnd]++; | |
1194 | rfLens[rfLensFnd++]=rfCounter; | |
1195 | } | |
1196 | } else { | |
1197 | firstBitFnd++; | |
1198 | } | |
1199 | rfCounter=0; | |
1200 | lastFCcnt=fcCounter; | |
1201 | } | |
1202 | fcCounter=0; | |
1203 | } else { | |
1204 | // count sample | |
1205 | fcCounter++; | |
1206 | rfCounter++; | |
1207 | } | |
1208 | } | |
1209 | uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; | |
1210 | ||
1211 | for (i=0; i<15; i++){ | |
1212 | //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); | |
1213 | //get highest 2 RF values (might need to get more values to compare or compare all?) | |
1214 | if (rfCnts[i]>rfCnts[rfHighest]){ | |
1215 | rfHighest3=rfHighest2; | |
1216 | rfHighest2=rfHighest; | |
1217 | rfHighest=i; | |
1218 | } else if(rfCnts[i]>rfCnts[rfHighest2]){ | |
1219 | rfHighest3=rfHighest2; | |
1220 | rfHighest2=i; | |
1221 | } else if(rfCnts[i]>rfCnts[rfHighest3]){ | |
1222 | rfHighest3=i; | |
1223 | } | |
1224 | } | |
1225 | // set allowed clock remainder tolerance to be 1 large field clock length+1 | |
1226 | // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off | |
1227 | uint8_t tol1 = fcHigh+1; | |
1228 | ||
1229 | //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); | |
1230 | ||
1231 | // loop to find the highest clock that has a remainder less than the tolerance | |
1232 | // compare samples counted divided by | |
1233 | int ii=7; | |
1234 | for (; ii>=0; ii--){ | |
1235 | if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ | |
1236 | if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ | |
1237 | if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ | |
1238 | break; | |
1239 | } | |
1240 | } | |
1241 | } | |
1242 | } | |
1243 | ||
1244 | if (ii<0) return 0; // oops we went too far | |
1245 | ||
1246 | return clk[ii]; | |
1247 | } | |
1248 | ||
1249 | //by marshmellow | |
1250 | //countFC is to detect the field clock lengths. | |
1251 | //counts and returns the 2 most common wave lengths | |
1252 | uint16_t countFC(uint8_t *BitStream, size_t size) | |
1253 | { | |
1254 | uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; | |
1255 | uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; | |
1256 | uint8_t fcLensFnd = 0; | |
1257 | uint8_t lastFCcnt=0; | |
1258 | uint32_t fcCounter = 0; | |
1259 | size_t i; | |
1260 | ||
1261 | // prime i to first up transition | |
1262 | for (i = 1; i < size-1; i++) | |
1263 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) | |
1264 | break; | |
1265 | ||
1266 | for (; i < size-1; i++){ | |
1267 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ | |
1268 | // new up transition | |
1269 | fcCounter++; | |
1270 | ||
1271 | //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) | |
1272 | if (lastFCcnt==5 && fcCounter==9) fcCounter--; | |
1273 | //if odd and not rc/5 add one (for when we get a fc 9 instead of 10) | |
1274 | if ((fcCounter==9 && fcCounter & 1) || fcCounter==4) fcCounter++; | |
1275 | ||
1276 | // save last field clock count (fc/xx) | |
1277 | // find which fcLens to save it to: | |
1278 | for (int ii=0; ii<10; ii++){ | |
1279 | if (fcLens[ii]==fcCounter){ | |
1280 | fcCnts[ii]++; | |
1281 | fcCounter=0; | |
1282 | break; | |
1283 | } | |
1284 | } | |
1285 | if (fcCounter>0 && fcLensFnd<10){ | |
1286 | //add new fc length | |
1287 | fcCnts[fcLensFnd]++; | |
1288 | fcLens[fcLensFnd++]=fcCounter; | |
1289 | } | |
1290 | fcCounter=0; | |
1291 | } else { | |
1292 | // count sample | |
1293 | fcCounter++; | |
1294 | } | |
1295 | } | |
1296 | ||
1297 | uint8_t best1=9, best2=9, best3=9; | |
1298 | uint16_t maxCnt1=0; | |
1299 | // go through fclens and find which ones are bigest 2 | |
1300 | for (i=0; i<10; i++){ | |
1301 | // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); | |
1302 | // get the 3 best FC values | |
1303 | if (fcCnts[i]>maxCnt1) { | |
1304 | best3=best2; | |
1305 | best2=best1; | |
1306 | maxCnt1=fcCnts[i]; | |
1307 | best1=i; | |
1308 | } else if(fcCnts[i]>fcCnts[best2]){ | |
1309 | best3=best2; | |
1310 | best2=i; | |
1311 | } else if(fcCnts[i]>fcCnts[best3]){ | |
1312 | best3=i; | |
1313 | } | |
1314 | } | |
1315 | uint8_t fcH=0, fcL=0; | |
1316 | if (fcLens[best1]>fcLens[best2]){ | |
1317 | fcH=fcLens[best1]; | |
1318 | fcL=fcLens[best2]; | |
1319 | } else{ | |
1320 | fcH=fcLens[best2]; | |
1321 | fcL=fcLens[best1]; | |
1322 | } | |
1323 | ||
1324 | // TODO: take top 3 answers and compare to known Field clocks to get top 2 | |
1325 | ||
1326 | uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; | |
1327 | // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); | |
1328 | ||
1329 | return fcs; | |
1330 | } |