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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 | #include "lfdemod.h" | |
11 | ||
12 | //un_comment to allow debug print calls when used not on device | |
13 | void dummy(char *fmt, ...){} | |
14 | ||
15 | ||
16 | #ifndef ON_DEVICE | |
17 | # include "ui.h" | |
18 | # include "cmdparser.h" | |
19 | # include "cmddata.h" | |
20 | # define prnt PrintAndLog | |
21 | #else | |
22 | uint8_t g_debugMode=0; | |
23 | # define prnt dummy | |
24 | #endif | |
25 | ||
26 | //test samples are not just noise | |
27 | uint8_t justNoise(uint8_t *bits, size_t size) { | |
28 | #define THRESHOLD 123 | |
29 | uint8_t val = 1; | |
30 | for(size_t idx=0; idx < size && val ;idx++) | |
31 | val = bits[idx] < THRESHOLD; | |
32 | return val; | |
33 | } | |
34 | ||
35 | //by marshmellow | |
36 | //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 | |
37 | int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo) | |
38 | { | |
39 | *high=0; | |
40 | *low=255; | |
41 | // get high and low thresholds | |
42 | for (size_t i=0; i < size; i++){ | |
43 | if (BitStream[i] > *high) *high = BitStream[i]; | |
44 | if (BitStream[i] < *low) *low = BitStream[i]; | |
45 | } | |
46 | if (*high < 123) return -1; // just noise | |
47 | *high = ((*high-128)*fuzzHi + 12800)/100; | |
48 | *low = ((*low-128)*fuzzLo + 12800)/100; | |
49 | return 1; | |
50 | } | |
51 | ||
52 | // by marshmellow | |
53 | // pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType | |
54 | // returns 1 if passed | |
55 | uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) | |
56 | { | |
57 | uint8_t ans = 0; | |
58 | for (uint8_t i = 0; i < bitLen; i++){ | |
59 | ans ^= ((bits >> i) & 1); | |
60 | } | |
61 | if (g_debugMode) prnt("DEBUG: ans: %d, ptype: %d, bits: %08X",ans,pType,bits); | |
62 | return (ans == pType); | |
63 | } | |
64 | ||
65 | //by marshmellow | |
66 | // takes a array of binary values, start position, length of bits per parity (includes parity bit), | |
67 | // Parity Type (1 for odd; 0 for even; 2 for Always 1's; 3 for Always 0's), and binary Length (length to run) | |
68 | size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) | |
69 | { | |
70 | uint32_t parityWd = 0; | |
71 | size_t j = 0, bitCnt = 0; | |
72 | for (int word = 0; word < (bLen); word += pLen){ | |
73 | for (int bit=0; bit < pLen; bit++){ | |
74 | parityWd = (parityWd << 1) | BitStream[startIdx+word+bit]; | |
75 | BitStream[j++] = (BitStream[startIdx+word+bit]); | |
76 | } | |
77 | if (word+pLen >= bLen) break; | |
78 | ||
79 | j--; // overwrite parity with next data | |
80 | // if parity fails then return 0 | |
81 | switch (pType) { | |
82 | case 3: if (BitStream[j]==1) { return 0; } break; //should be 0 spacer bit | |
83 | case 2: if (BitStream[j]==0) { return 0; } break; //should be 1 spacer bit | |
84 | default: if (parityTest(parityWd, pLen, pType) == 0) { return 0; } break; //test parity | |
85 | } | |
86 | bitCnt += (pLen-1); | |
87 | parityWd = 0; | |
88 | } | |
89 | // if we got here then all the parities passed | |
90 | //return ID start index and size | |
91 | return bitCnt; | |
92 | } | |
93 | ||
94 | // by marshmellow | |
95 | // takes a array of binary values, length of bits per parity (includes parity bit), | |
96 | // Parity Type (1 for odd; 0 for even; 2 Always 1's; 3 Always 0's), and binary Length (length to run) | |
97 | // Make sure *dest is long enough to store original sourceLen + #_of_parities_to_be_added | |
98 | size_t addParity(uint8_t *BitSource, uint8_t *dest, uint8_t sourceLen, uint8_t pLen, uint8_t pType) | |
99 | { | |
100 | uint32_t parityWd = 0; | |
101 | size_t j = 0, bitCnt = 0; | |
102 | for (int word = 0; word < sourceLen; word+=pLen-1) { | |
103 | for (int bit=0; bit < pLen-1; bit++){ | |
104 | parityWd = (parityWd << 1) | BitSource[word+bit]; | |
105 | dest[j++] = (BitSource[word+bit]); | |
106 | } | |
107 | ||
108 | // if parity fails then return 0 | |
109 | switch (pType) { | |
110 | case 3: dest[j++]=0; break; // marker bit which should be a 0 | |
111 | case 2: dest[j++]=1; break; // marker bit which should be a 1 | |
112 | default: | |
113 | dest[j++] = parityTest(parityWd, pLen-1, pType) ^ 1; | |
114 | break; | |
115 | } | |
116 | bitCnt += pLen; | |
117 | parityWd = 0; | |
118 | } | |
119 | // if we got here then all the parities passed | |
120 | //return ID start index and size | |
121 | return bitCnt; | |
122 | } | |
123 | ||
124 | uint32_t bytebits_to_byte(uint8_t *src, size_t numbits) | |
125 | { | |
126 | uint32_t num = 0; | |
127 | for(int i = 0 ; i < numbits ; i++) { | |
128 | num = (num << 1) | (*src); | |
129 | src++; | |
130 | } | |
131 | return num; | |
132 | } | |
133 | ||
134 | //least significant bit first | |
135 | uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits) | |
136 | { | |
137 | uint32_t num = 0; | |
138 | for(int i = 0 ; i < numbits ; i++) { | |
139 | num = (num << 1) | *(src + (numbits-(i+1))); | |
140 | } | |
141 | return num; | |
142 | } | |
143 | ||
144 | //by marshmellow | |
145 | // search for given preamble in given BitStream and return success=1 or fail=0 and startIndex (where it was found) | |
146 | bool preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx){ | |
147 | return preambleSearchEx(BitStream, preamble, pLen, size, startIdx, false); | |
148 | } | |
149 | //by marshmellow | |
150 | //search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length | |
151 | // param @findone: look for a repeating preamble or only the first. | |
152 | // em4x05/4x69 only sends preamble once, so look for it once in the first pLen bits | |
153 | bool preambleSearchEx(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone) | |
154 | { | |
155 | // Sanity check. If preamble length is bigger than bitstream length. | |
156 | if ( *size <= pLen ) return false; | |
157 | ||
158 | uint8_t foundCnt = 0; | |
159 | for (int idx = 0; idx < *size - pLen; idx++){ | |
160 | if (memcmp(BitStream+idx, preamble, pLen) == 0){ | |
161 | if (g_debugMode) prnt("DEBUG: preamble found at %u", idx); | |
162 | //first index found | |
163 | foundCnt++; | |
164 | if (foundCnt == 1){ | |
165 | *startIdx = idx; | |
166 | if (findone) return true; | |
167 | } | |
168 | if (foundCnt == 2){ | |
169 | *size = idx - *startIdx; | |
170 | return true; | |
171 | } | |
172 | } | |
173 | } | |
174 | return false; | |
175 | } | |
176 | ||
177 | // find start of modulating data (for fsk and psk) in case of beginning noise or slow chip startup. | |
178 | size_t findModStart(uint8_t dest[], size_t size, uint8_t threshold_value, uint8_t expWaveSize) { | |
179 | size_t i = 0; | |
180 | size_t waveSizeCnt = 0; | |
181 | uint8_t thresholdCnt = 0; | |
182 | bool isAboveThreshold = dest[i++] >= threshold_value; | |
183 | for (; i < size-20; i++ ) { | |
184 | if(dest[i] < threshold_value && isAboveThreshold) { | |
185 | thresholdCnt++; | |
186 | if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break; | |
187 | isAboveThreshold = false; | |
188 | waveSizeCnt = 0; | |
189 | } else if (dest[i] >= threshold_value && !isAboveThreshold) { | |
190 | thresholdCnt++; | |
191 | if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break; | |
192 | isAboveThreshold = true; | |
193 | waveSizeCnt = 0; | |
194 | } else { | |
195 | waveSizeCnt++; | |
196 | } | |
197 | if (thresholdCnt > 10) break; | |
198 | } | |
199 | if (g_debugMode == 2) prnt("DEBUG: threshold Count reached at %u, count: %u",i, thresholdCnt); | |
200 | return i; | |
201 | } | |
202 | ||
203 | //by marshmellow | |
204 | //takes 1s and 0s and searches for EM410x format - output EM ID | |
205 | // actually, no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future | |
206 | uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) | |
207 | { | |
208 | //allow only 1s and 0s | |
209 | // only checking first bitvalue?! | |
210 | if (BitStream[1] > 1) return 0; | |
211 | ||
212 | uint32_t i = 0, idx = 0, parityBits = 0; | |
213 | uint8_t fmtlen = 0; | |
214 | *startIdx = 0; | |
215 | ||
216 | // preamble 0111111111 | |
217 | // include 0 in front to help get start pos | |
218 | uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1}; | |
219 | if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx)) | |
220 | return 0; | |
221 | if (*size < 64) return 0; | |
222 | ||
223 | fmtlen = (*size > 64) ? 22 : 10; | |
224 | ||
225 | idx = *startIdx + sizeof(preamble); | |
226 | ||
227 | //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits) | |
228 | for (i=0; i < fmtlen; i++){ | |
229 | parityBits = bytebits_to_byte(BitStream + (i*5) + idx, 5); | |
230 | //check even parity | |
231 | if (parityTest(parityBits, 5, 0) == 0) return 0; | |
232 | //set uint64 with ID from BitStream | |
233 | for (uint8_t j = 0; j < 4; j++){ | |
234 | *hi = (*hi << 1) | (*lo >> 63); | |
235 | *lo = (*lo << 1) | (BitStream[(i*5) + j + idx]); | |
236 | } | |
237 | } | |
238 | //skip last 5 bit parity test for simplicity. | |
239 | // *size = 64 | 128; | |
240 | return 1; | |
241 | } | |
242 | ||
243 | //by marshmellow | |
244 | //demodulates strong heavily clipped samples | |
245 | int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low) | |
246 | { | |
247 | size_t bitCnt=0, smplCnt=0, errCnt=0; | |
248 | uint8_t waveHigh = 0; | |
249 | for (size_t i=0; i < *size; i++){ | |
250 | if (BinStream[i] >= high && waveHigh){ | |
251 | smplCnt++; | |
252 | } else if (BinStream[i] <= low && !waveHigh){ | |
253 | smplCnt++; | |
254 | } else { //transition | |
255 | if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){ | |
256 | ||
257 | if (smplCnt > clk-(clk/4)-1) { //full clock | |
258 | if (smplCnt > clk + (clk/4)+1) { //too many samples | |
259 | errCnt++; | |
260 | if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i); | |
261 | BinStream[bitCnt++] = 7; | |
262 | } else if (waveHigh) { | |
263 | BinStream[bitCnt++] = invert; | |
264 | BinStream[bitCnt++] = invert; | |
265 | } else if (!waveHigh) { | |
266 | BinStream[bitCnt++] = invert ^ 1; | |
267 | BinStream[bitCnt++] = invert ^ 1; | |
268 | } | |
269 | waveHigh ^= 1; | |
270 | smplCnt = 0; | |
271 | } else if (smplCnt > (clk/2) - (clk/4)-1) { | |
272 | if (waveHigh) { | |
273 | BinStream[bitCnt++] = invert; | |
274 | } else if (!waveHigh) { | |
275 | BinStream[bitCnt++] = invert ^ 1; | |
276 | } | |
277 | waveHigh ^= 1; | |
278 | smplCnt = 0; | |
279 | } else if (!bitCnt) { | |
280 | //first bit | |
281 | waveHigh = (BinStream[i] >= high); | |
282 | smplCnt = 1; | |
283 | } else { | |
284 | smplCnt++; | |
285 | //transition bit oops | |
286 | } | |
287 | } else { //haven't hit new high or new low yet | |
288 | smplCnt++; | |
289 | } | |
290 | } | |
291 | } | |
292 | *size = bitCnt; | |
293 | return errCnt; | |
294 | } | |
295 | ||
296 | //by marshmellow | |
297 | void askAmp(uint8_t *BitStream, size_t size) | |
298 | { | |
299 | uint8_t last = 128; | |
300 | for(size_t i = 1; i < size; ++i){ | |
301 | if (BitStream[i]-BitStream[i-1] >= 30) //large jump up | |
302 | last = 255; | |
303 | else if(BitStream[i-1] - BitStream[i] >= 20) //large jump down | |
304 | last = 0; | |
305 | ||
306 | BitStream[i] = last; | |
307 | } | |
308 | } | |
309 | ||
310 | //by marshmellow | |
311 | //attempts to demodulate ask modulations, askType == 0 for ask/raw, askType==1 for ask/manchester | |
312 | int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp, uint8_t askType) | |
313 | { | |
314 | if (*size==0) return -1; | |
315 | int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default | |
316 | ||
317 | if (*clk==0 || start < 0) return -3; | |
318 | if (*invert != 1) *invert = 0; | |
319 | if (amp==1) askAmp(BinStream, *size); | |
320 | if (g_debugMode==2) prnt("DEBUG ASK: clk %d, beststart %d, amp %d", *clk, start, amp); | |
321 | ||
322 | uint8_t initLoopMax = 255; | |
323 | if (initLoopMax > *size) initLoopMax = *size; | |
324 | // Detect high and lows | |
325 | //25% clip in case highs and lows aren't clipped [marshmellow] | |
326 | int high, low; | |
327 | if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) | |
328 | return -2; //just noise | |
329 | ||
330 | size_t errCnt = 0; | |
331 | // if clean clipped waves detected run alternate demod | |
332 | if (DetectCleanAskWave(BinStream, *size, high, low)) { | |
333 | if (g_debugMode==2) prnt("DEBUG ASK: Clean Wave Detected - using clean wave demod"); | |
334 | errCnt = cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); | |
335 | if (askType) //askman | |
336 | return manrawdecode(BinStream, size, 0); | |
337 | //askraw | |
338 | return errCnt; | |
339 | } | |
340 | if (g_debugMode==2) prnt("DEBUG ASK: Weak Wave Detected - using weak wave demod"); | |
341 | ||
342 | int lastBit; //set first clock check - can go negative | |
343 | size_t i, bitnum = 0; //output counter | |
344 | uint8_t midBit = 0; | |
345 | 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 | |
346 | 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 | |
347 | size_t MaxBits = 3072; //max bits to collect | |
348 | lastBit = start - *clk; | |
349 | ||
350 | for (i = start; i < *size; ++i) { | |
351 | if (i-lastBit >= *clk-tol){ | |
352 | if (BinStream[i] >= high) { | |
353 | BinStream[bitnum++] = *invert; | |
354 | } else if (BinStream[i] <= low) { | |
355 | BinStream[bitnum++] = *invert ^ 1; | |
356 | } else if (i-lastBit >= *clk+tol) { | |
357 | if (bitnum > 0) { | |
358 | if (g_debugMode==2) prnt("DEBUG ASK: Modulation Error at: %u", i); | |
359 | BinStream[bitnum++]=7; | |
360 | errCnt++; | |
361 | } | |
362 | } else { //in tolerance - looking for peak | |
363 | continue; | |
364 | } | |
365 | midBit = 0; | |
366 | lastBit += *clk; | |
367 | } else if (i-lastBit >= (*clk/2-tol) && !midBit && !askType){ | |
368 | if (BinStream[i] >= high) { | |
369 | BinStream[bitnum++] = *invert; | |
370 | } else if (BinStream[i] <= low) { | |
371 | BinStream[bitnum++] = *invert ^ 1; | |
372 | } else if (i-lastBit >= *clk/2+tol) { | |
373 | BinStream[bitnum] = BinStream[bitnum-1]; | |
374 | bitnum++; | |
375 | } else { //in tolerance - looking for peak | |
376 | continue; | |
377 | } | |
378 | midBit = 1; | |
379 | } | |
380 | if (bitnum >= MaxBits) break; | |
381 | } | |
382 | *size = bitnum; | |
383 | return errCnt; | |
384 | } | |
385 | //by marshmellow | |
386 | //take 10 and 01 and manchester decode | |
387 | //run through 2 times and take least errCnt | |
388 | int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert){ | |
389 | int errCnt = 0, bestErr = 1000; | |
390 | uint16_t bitnum = 0, MaxBits = 512, bestRun = 0; | |
391 | size_t i, k; | |
392 | if (*size < 16) return -1; | |
393 | //find correct start position [alignment] | |
394 | for (k=0; k < 2; ++k){ | |
395 | for (i=k; i<*size-3; i += 2) | |
396 | if (BitStream[i] == BitStream[i+1]) | |
397 | errCnt++; | |
398 | ||
399 | if (bestErr > errCnt){ | |
400 | bestErr = errCnt; | |
401 | bestRun = k; | |
402 | } | |
403 | errCnt=0; | |
404 | } | |
405 | //decode | |
406 | for (i=bestRun; i < *size-3; i += 2){ | |
407 | if (BitStream[i] == 1 && (BitStream[i+1] == 0)){ | |
408 | BitStream[bitnum++] = invert; | |
409 | } else if ((BitStream[i] == 0) && BitStream[i+1] == 1){ | |
410 | BitStream[bitnum++] = invert^1; | |
411 | } else { | |
412 | BitStream[bitnum++] = 7; | |
413 | } | |
414 | if (bitnum>MaxBits) break; | |
415 | } | |
416 | *size=bitnum; | |
417 | return bestErr; | |
418 | } | |
419 | ||
420 | uint32_t manchesterEncode2Bytes(uint16_t datain) { | |
421 | uint32_t output = 0; | |
422 | uint8_t curBit = 0; | |
423 | for (uint8_t i=0; i<16; i++) { | |
424 | curBit = (datain >> (15-i) & 1); | |
425 | output |= (1<<(((15-i)*2)+curBit)); | |
426 | } | |
427 | return output; | |
428 | } | |
429 | ||
430 | //by marshmellow | |
431 | //encode binary data into binary manchester | |
432 | int ManchesterEncode(uint8_t *BitStream, size_t size) | |
433 | { | |
434 | size_t modIdx=20000, i=0; | |
435 | if (size>modIdx) return -1; | |
436 | for (size_t idx=0; idx < size; idx++){ | |
437 | BitStream[idx+modIdx++] = BitStream[idx]; | |
438 | BitStream[idx+modIdx++] = BitStream[idx]^1; | |
439 | } | |
440 | for (; i<(size*2); i++){ | |
441 | BitStream[i] = BitStream[i+20000]; | |
442 | } | |
443 | return i; | |
444 | } | |
445 | ||
446 | //by marshmellow | |
447 | //take 01 or 10 = 1 and 11 or 00 = 0 | |
448 | //check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010 | |
449 | //decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding | |
450 | int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) | |
451 | { | |
452 | uint16_t bitnum = 0; | |
453 | uint16_t errCnt = 0; | |
454 | size_t i = offset; | |
455 | uint16_t MaxBits=512; | |
456 | //if not enough samples - error | |
457 | if (*size < 51) return -1; | |
458 | //check for phase change faults - skip one sample if faulty | |
459 | uint8_t offsetA = 1, offsetB = 1; | |
460 | for (; i<48; i+=2){ | |
461 | if (BitStream[i+1]==BitStream[i+2]) offsetA=0; | |
462 | if (BitStream[i+2]==BitStream[i+3]) offsetB=0; | |
463 | } | |
464 | if (!offsetA && offsetB) offset++; | |
465 | for (i=offset; i<*size-3; i+=2){ | |
466 | //check for phase error | |
467 | if (BitStream[i+1]==BitStream[i+2]) { | |
468 | BitStream[bitnum++]=7; | |
469 | errCnt++; | |
470 | } | |
471 | if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){ | |
472 | BitStream[bitnum++]=1^invert; | |
473 | } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){ | |
474 | BitStream[bitnum++]=invert; | |
475 | } else { | |
476 | BitStream[bitnum++]=7; | |
477 | errCnt++; | |
478 | } | |
479 | if(bitnum>MaxBits) break; | |
480 | } | |
481 | *size=bitnum; | |
482 | return errCnt; | |
483 | } | |
484 | ||
485 | // by marshmellow | |
486 | // demod gProxIIDemod | |
487 | // error returns as -x | |
488 | // success returns start position in BitStream | |
489 | // BitStream must contain previously askrawdemod and biphasedemoded data | |
490 | int gProxII_Demod(uint8_t BitStream[], size_t *size) | |
491 | { | |
492 | size_t startIdx=0; | |
493 | uint8_t preamble[] = {1,1,1,1,1,0}; | |
494 | ||
495 | if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx)) | |
496 | return -3; //preamble not found | |
497 | ||
498 | if (*size != 96) return -2; //should have found 96 bits | |
499 | ||
500 | //check first 6 spacer bits to verify format | |
501 | if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){ | |
502 | //confirmed proper separator bits found | |
503 | //return start position | |
504 | return (int) startIdx; | |
505 | } | |
506 | return -5; //spacer bits not found - not a valid gproxII | |
507 | } | |
508 | ||
509 | //translate wave to 11111100000 (1 for each short wave [higher freq] 0 for each long wave [lower freq]) | |
510 | size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) | |
511 | { | |
512 | size_t last_transition = 0; | |
513 | size_t idx = 1; | |
514 | if (fchigh==0) fchigh=10; | |
515 | if (fclow==0) fclow=8; | |
516 | //set the threshold close to 0 (graph) or 128 std to avoid static | |
517 | uint8_t threshold_value = 123; | |
518 | size_t preLastSample = 0; | |
519 | size_t LastSample = 0; | |
520 | size_t currSample = 0; | |
521 | if ( size < 1024 ) return 0; // not enough samples | |
522 | ||
523 | //find start of modulating data in trace | |
524 | idx = findModStart(dest, size, threshold_value, fchigh); | |
525 | ||
526 | // Need to threshold first sample | |
527 | if(dest[idx] < threshold_value) dest[0] = 0; | |
528 | else dest[0] = 1; | |
529 | idx++; | |
530 | ||
531 | size_t numBits = 0; | |
532 | // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8) | |
533 | // or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere | |
534 | // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10 | |
535 | // (could also be fc/5 && fc/7 for fsk1 = 4-9) | |
536 | for(; idx < size-20; idx++) { | |
537 | // threshold current value | |
538 | ||
539 | if (dest[idx] < threshold_value) dest[idx] = 0; | |
540 | else dest[idx] = 1; | |
541 | ||
542 | // Check for 0->1 transition | |
543 | if (dest[idx-1] < dest[idx]) { | |
544 | preLastSample = LastSample; | |
545 | LastSample = currSample; | |
546 | currSample = idx-last_transition; | |
547 | if (currSample < (fclow-2)){ //0-5 = garbage noise (or 0-3) | |
548 | //do nothing with extra garbage | |
549 | } else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves (or 3-6 = 5) | |
550 | //correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5) | |
551 | if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1))){ | |
552 | dest[numBits-1]=1; | |
553 | } | |
554 | dest[numBits++]=1; | |
555 | ||
556 | } else if (currSample > (fchigh+1) && numBits < 3) { //12 + and first two bit = unusable garbage | |
557 | //do nothing with beginning garbage and reset.. should be rare.. | |
558 | numBits = 0; | |
559 | } 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) | |
560 | dest[numBits++]=1; | |
561 | } else { //9+ = 10 sample waves (or 6+ = 7) | |
562 | dest[numBits++]=0; | |
563 | } | |
564 | last_transition = idx; | |
565 | } | |
566 | } | |
567 | return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0 | |
568 | } | |
569 | ||
570 | //translate 11111100000 to 10 | |
571 | //rfLen = clock, fchigh = larger field clock, fclow = smaller field clock | |
572 | size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, | |
573 | uint8_t invert, uint8_t fchigh, uint8_t fclow) | |
574 | { | |
575 | uint8_t lastval=dest[0]; | |
576 | size_t idx=0; | |
577 | size_t numBits=0; | |
578 | uint32_t n=1; | |
579 | for( idx=1; idx < size; idx++) { | |
580 | n++; | |
581 | if (dest[idx]==lastval) continue; //skip until we hit a transition | |
582 | ||
583 | //find out how many bits (n) we collected | |
584 | //if lastval was 1, we have a 1->0 crossing | |
585 | if (dest[idx-1]==1) { | |
586 | n = (n * fclow + rfLen/2) / rfLen; | |
587 | } else {// 0->1 crossing | |
588 | n = (n * fchigh + rfLen/2) / rfLen; | |
589 | } | |
590 | if (n == 0) n = 1; | |
591 | ||
592 | //add to our destination the bits we collected | |
593 | memset(dest+numBits, dest[idx-1]^invert , n); | |
594 | numBits += n; | |
595 | n=0; | |
596 | lastval=dest[idx]; | |
597 | }//end for | |
598 | // if valid extra bits at the end were all the same frequency - add them in | |
599 | if (n > rfLen/fchigh) { | |
600 | if (dest[idx-2]==1) { | |
601 | n = (n * fclow + rfLen/2) / rfLen; | |
602 | } else { | |
603 | n = (n * fchigh + rfLen/2) / rfLen; | |
604 | } | |
605 | memset(dest+numBits, dest[idx-1]^invert , n); | |
606 | numBits += n; | |
607 | } | |
608 | return numBits; | |
609 | } | |
610 | ||
611 | //by marshmellow (from holiman's base) | |
612 | // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod) | |
613 | int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) | |
614 | { | |
615 | // FSK demodulator | |
616 | size = fsk_wave_demod(dest, size, fchigh, fclow); | |
617 | size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow); | |
618 | return size; | |
619 | } | |
620 | ||
621 | // loop to get raw HID waveform then FSK demodulate the TAG ID from it | |
622 | int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) | |
623 | { | |
624 | if (justNoise(dest, *size)) return -1; | |
625 | ||
626 | size_t numStart=0, size2 = *size, startIdx=0; | |
627 | // FSK demodulator | |
628 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a | |
629 | if (*size < 96*2) return -2; | |
630 | // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 | |
631 | uint8_t preamble[] = {0,0,0,1,1,1,0,1}; | |
632 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
633 | return -3; //preamble not found | |
634 | ||
635 | numStart = startIdx + sizeof(preamble); | |
636 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
637 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
638 | if (dest[idx] == dest[idx+1]){ | |
639 | return -4; //not manchester data | |
640 | } | |
641 | *hi2 = (*hi2<<1)|(*hi>>31); | |
642 | *hi = (*hi<<1)|(*lo>>31); | |
643 | //Then, shift in a 0 or one into low | |
644 | *lo <<= 1; | |
645 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
646 | *lo |= 1; | |
647 | else // 0 1 | |
648 | *lo |= 0; | |
649 | } | |
650 | return (int)startIdx; | |
651 | } | |
652 | ||
653 | // loop to get raw paradox waveform then FSK demodulate the TAG ID from it | |
654 | int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) | |
655 | { | |
656 | if (justNoise(dest, *size)) return -1; | |
657 | ||
658 | size_t numStart=0, size2 = *size, startIdx=0; | |
659 | // FSK demodulator | |
660 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a | |
661 | if (*size < 96) return -2; | |
662 | ||
663 | // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 | |
664 | uint8_t preamble[] = {0,0,0,0,1,1,1,1}; | |
665 | if (preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
666 | return -3; //preamble not found | |
667 | ||
668 | numStart = startIdx + sizeof(preamble); | |
669 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
670 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
671 | if (dest[idx] == dest[idx+1]) | |
672 | return -4; //not manchester data | |
673 | *hi2 = (*hi2<<1)|(*hi>>31); | |
674 | *hi = (*hi<<1)|(*lo>>31); | |
675 | //Then, shift in a 0 or one into low | |
676 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
677 | *lo=(*lo<<1)|1; | |
678 | else // 0 1 | |
679 | *lo=(*lo<<1)|0; | |
680 | } | |
681 | return (int)startIdx; | |
682 | } | |
683 | ||
684 | int IOdemodFSK(uint8_t *dest, size_t size) | |
685 | { | |
686 | if (justNoise(dest, size)) return -1; | |
687 | //make sure buffer has data | |
688 | if (size < 66*64) return -2; | |
689 | // FSK demodulator | |
690 | size = fskdemod(dest, size, 64, 1, 10, 8); // FSK2a RF/64 | |
691 | if (size < 65) return -3; //did we get a good demod? | |
692 | //Index map | |
693 | //0 10 20 30 40 50 60 | |
694 | //| | | | | | | | |
695 | //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23 | |
696 | //----------------------------------------------------------------------------- | |
697 | //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11 | |
698 | // | |
699 | //XSF(version)facility:codeone+codetwo | |
700 | //Handle the data | |
701 | size_t startIdx = 0; | |
702 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1}; | |
703 | if (! preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx)) | |
704 | return -4; //preamble not found | |
705 | ||
706 | if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){ | |
707 | //confirmed proper separator bits found | |
708 | //return start position | |
709 | return (int) startIdx; | |
710 | } | |
711 | return -5; | |
712 | } | |
713 | ||
714 | // by marshmellow | |
715 | // find viking preamble 0xF200 in already demoded data | |
716 | int VikingDemod_AM(uint8_t *dest, size_t *size) { | |
717 | //make sure buffer has data | |
718 | if (*size < 64*2) return -2; | |
719 | size_t startIdx = 0; | |
720 | 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}; | |
721 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
722 | return -4; //preamble not found | |
723 | ||
724 | uint32_t checkCalc = bytebits_to_byte(dest+startIdx,8) ^ | |
725 | bytebits_to_byte(dest+startIdx+8,8) ^ | |
726 | bytebits_to_byte(dest+startIdx+16,8) ^ | |
727 | bytebits_to_byte(dest+startIdx+24,8) ^ | |
728 | bytebits_to_byte(dest+startIdx+32,8) ^ | |
729 | bytebits_to_byte(dest+startIdx+40,8) ^ | |
730 | bytebits_to_byte(dest+startIdx+48,8) ^ | |
731 | bytebits_to_byte(dest+startIdx+56,8); | |
732 | if ( checkCalc != 0xA8 ) return -5; | |
733 | if (*size != 64) return -6; | |
734 | //return start position | |
735 | return (int)startIdx; | |
736 | } | |
737 | ||
738 | // by iceman | |
739 | // find Visa2000 preamble in already demoded data | |
740 | int Visa2kDemod_AM(uint8_t *dest, size_t *size) { | |
741 | if (*size < 96) return -1; //make sure buffer has data | |
742 | size_t startIdx = 0; | |
743 | uint8_t preamble[] = {0,1,0,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0}; | |
744 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
745 | return -2; //preamble not found | |
746 | if (*size != 96) return -3; //wrong demoded size | |
747 | //return start position | |
748 | return (int)startIdx; | |
749 | } | |
750 | // by iceman | |
751 | // find Noralsy preamble in already demoded data | |
752 | int NoralsyDemod_AM(uint8_t *dest, size_t *size) { | |
753 | if (*size < 96) return -1; //make sure buffer has data | |
754 | size_t startIdx = 0; | |
755 | uint8_t preamble[] = {1,0,1,1,1,0,1,1,0,0,0,0}; | |
756 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
757 | return -2; //preamble not found | |
758 | if (*size != 96) return -3; //wrong demoded size | |
759 | //return start position | |
760 | return (int)startIdx; | |
761 | } | |
762 | // find presco preamble 0x10D in already demoded data | |
763 | int PrescoDemod(uint8_t *dest, size_t *size) { | |
764 | if (*size < 128*2) return -1; //make sure buffer has data | |
765 | size_t startIdx = 0; | |
766 | uint8_t preamble[] = {0,0,0,1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0}; | |
767 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
768 | return -2; //preamble not found | |
769 | if (*size != 128) return -3; //wrong demoded size | |
770 | //return start position | |
771 | return (int)startIdx; | |
772 | } | |
773 | ||
774 | // Ask/Biphase Demod then try to locate an ISO 11784/85 ID | |
775 | // BitStream must contain previously askrawdemod and biphasedemoded data | |
776 | int FDXBdemodBI(uint8_t *dest, size_t *size) { | |
777 | if (*size < 128*2) return -1; //make sure buffer has enough data | |
778 | size_t startIdx = 0; | |
779 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1}; | |
780 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
781 | return -2; //preamble not found | |
782 | if (*size != 128) return -3; //wrong demoded size | |
783 | //return start position | |
784 | return (int)startIdx; | |
785 | } | |
786 | ||
787 | // ASK/Diphase fc/64 (inverted Biphase) | |
788 | // Note: this i s not a demod, this is only a detection | |
789 | // the parameter *dest needs to be demoded before call | |
790 | // 0xFFFF preamble, 64bits | |
791 | int JablotronDemod(uint8_t *dest, size_t *size){ | |
792 | if (*size < 64*2) return -1; //make sure buffer has enough data | |
793 | size_t startIdx = 0; | |
794 | uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0}; | |
795 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
796 | return -2; //preamble not found | |
797 | if (*size != 64) return -3; // wrong demoded size | |
798 | ||
799 | uint8_t checkchksum = 0; | |
800 | for (int i=16; i < 56; i += 8) { | |
801 | checkchksum += bytebits_to_byte(dest+startIdx+i,8); | |
802 | } | |
803 | checkchksum ^= 0x3A; | |
804 | uint8_t crc = bytebits_to_byte(dest+startIdx+56, 8); | |
805 | if ( checkchksum != crc ) return -5; | |
806 | return (int)startIdx; | |
807 | } | |
808 | ||
809 | // by marshmellow | |
810 | // FSK Demod then try to locate an AWID ID | |
811 | int AWIDdemodFSK(uint8_t *dest, size_t *size) | |
812 | { | |
813 | //make sure buffer has enough data | |
814 | if (*size < 96*50) return -1; | |
815 | ||
816 | if (justNoise(dest, *size)) return -2; | |
817 | ||
818 | // FSK demodulator | |
819 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 | |
820 | if (*size < 96) return -3; //did we get a good demod? | |
821 | ||
822 | uint8_t preamble[] = {0,0,0,0,0,0,0,1}; | |
823 | size_t startIdx = 0; | |
824 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
825 | return -4; //preamble not found | |
826 | if (*size != 96) return -5; | |
827 | return (int)startIdx; | |
828 | } | |
829 | ||
830 | // by marshmellow | |
831 | // FSK Demod then try to locate a Farpointe Data (pyramid) ID | |
832 | int PyramiddemodFSK(uint8_t *dest, size_t *size) | |
833 | { | |
834 | //make sure buffer has data | |
835 | if (*size < 128*50) return -5; | |
836 | ||
837 | //test samples are not just noise | |
838 | if (justNoise(dest, *size)) return -1; | |
839 | ||
840 | // FSK demodulator | |
841 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 | |
842 | if (*size < 128) return -2; //did we get a good demod? | |
843 | size_t startIdx = 0; | |
844 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1}; | |
845 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
846 | return -4; //preamble not found | |
847 | if (*size != 128) return -3; | |
848 | return (int)startIdx; | |
849 | } | |
850 | ||
851 | // find nedap preamble in already demoded data | |
852 | int NedapDemod(uint8_t *dest, size_t *size) { | |
853 | //make sure buffer has data | |
854 | if (*size < 128) return -3; | |
855 | ||
856 | size_t startIdx = 0; | |
857 | //uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0,0,0,1}; | |
858 | uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0}; | |
859 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
860 | return -4; //preamble not found | |
861 | return (int) startIdx; | |
862 | } | |
863 | ||
864 | // Find IDTEC PSK1, RF Preamble == 0x4944544B, Demodsize 64bits | |
865 | // by iceman | |
866 | int IdteckDemodPSK(uint8_t *dest, size_t *size) { | |
867 | //make sure buffer has data | |
868 | if (*size < 64*2) return -1; | |
869 | size_t startIdx = 0; | |
870 | uint8_t preamble[] = {0,1,0,0,1,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,1,0,1,1}; | |
871 | if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) | |
872 | return -2; //preamble not found | |
873 | if (*size != 64) return -3; // wrong demoded size | |
874 | return (int) startIdx; | |
875 | } | |
876 | ||
877 | // by marshmellow | |
878 | // to detect a wave that has heavily clipped (clean) samples | |
879 | uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low) | |
880 | { | |
881 | bool allArePeaks = true; | |
882 | uint16_t cntPeaks=0; | |
883 | size_t loopEnd = 512+160; | |
884 | if (loopEnd > size) loopEnd = size; | |
885 | for (size_t i=160; i<loopEnd; i++){ | |
886 | if (dest[i]>low && dest[i]<high) | |
887 | allArePeaks = false; | |
888 | else | |
889 | cntPeaks++; | |
890 | } | |
891 | if (!allArePeaks){ | |
892 | if (cntPeaks > 300) return true; | |
893 | } | |
894 | return allArePeaks; | |
895 | } | |
896 | // by marshmellow | |
897 | // to help detect clocks on heavily clipped samples | |
898 | // based on count of low to low | |
899 | int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low) | |
900 | { | |
901 | uint8_t fndClk[] = {8,16,32,40,50,64,128}; | |
902 | size_t startwave; | |
903 | size_t i = 100; | |
904 | size_t minClk = 255; | |
905 | // get to first full low to prime loop and skip incomplete first pulse | |
906 | while ((dest[i] < high) && (i < size)) | |
907 | ++i; | |
908 | while ((dest[i] > low) && (i < size)) | |
909 | ++i; | |
910 | ||
911 | // loop through all samples | |
912 | while (i < size) { | |
913 | // measure from low to low | |
914 | while ((dest[i] > low) && (i < size)) | |
915 | ++i; | |
916 | startwave= i; | |
917 | while ((dest[i] < high) && (i < size)) | |
918 | ++i; | |
919 | while ((dest[i] > low) && (i < size)) | |
920 | ++i; | |
921 | //get minimum measured distance | |
922 | if (i-startwave < minClk && i < size) | |
923 | minClk = i - startwave; | |
924 | } | |
925 | // set clock | |
926 | if (g_debugMode==2) prnt("DEBUG ASK: detectstrongASKclk smallest wave: %d",minClk); | |
927 | for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { | |
928 | if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) | |
929 | return fndClk[clkCnt]; | |
930 | } | |
931 | return 0; | |
932 | } | |
933 | ||
934 | // by marshmellow | |
935 | // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping) | |
936 | // maybe somehow adjust peak trimming value based on samples to fix? | |
937 | // return start index of best starting position for that clock and return clock (by reference) | |
938 | int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) | |
939 | { | |
940 | size_t i=1; | |
941 | uint8_t clk[] = {255,8,16,32,40,50,64,100,128,255}; | |
942 | uint8_t clkEnd = 9; | |
943 | uint8_t loopCnt = 255; //don't need to loop through entire array... | |
944 | if (size <= loopCnt+60) return -1; //not enough samples | |
945 | size -= 60; //sometimes there is a strange end wave - filter out this.... | |
946 | //if we already have a valid clock | |
947 | uint8_t clockFnd=0; | |
948 | for (;i<clkEnd;++i) | |
949 | if (clk[i] == *clock) clockFnd = i; | |
950 | //clock found but continue to find best startpos | |
951 | ||
952 | //get high and low peak | |
953 | int peak, low; | |
954 | if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1; | |
955 | ||
956 | //test for large clean peaks | |
957 | if (!clockFnd){ | |
958 | if (DetectCleanAskWave(dest, size, peak, low)==1){ | |
959 | int ans = DetectStrongAskClock(dest, size, peak, low); | |
960 | if (g_debugMode==2) prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %d",ans); | |
961 | for (i=clkEnd-1; i>0; i--){ | |
962 | if (clk[i] == ans) { | |
963 | *clock = ans; | |
964 | //clockFnd = i; | |
965 | return 0; // for strong waves i don't use the 'best start position' yet... | |
966 | //break; //clock found but continue to find best startpos [not yet] | |
967 | } | |
968 | } | |
969 | } | |
970 | } | |
971 | uint8_t ii; | |
972 | uint8_t clkCnt, tol = 0; | |
973 | uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; | |
974 | uint8_t bestStart[]={0,0,0,0,0,0,0,0,0}; | |
975 | size_t errCnt = 0; | |
976 | size_t arrLoc, loopEnd; | |
977 | ||
978 | if (clockFnd>0) { | |
979 | clkCnt = clockFnd; | |
980 | clkEnd = clockFnd+1; | |
981 | } else { | |
982 | clkCnt=1; | |
983 | } | |
984 | ||
985 | //test each valid clock from smallest to greatest to see which lines up | |
986 | for(; clkCnt < clkEnd; clkCnt++) { | |
987 | if (clk[clkCnt] <= 32) { | |
988 | tol=1; | |
989 | } else { | |
990 | tol=0; | |
991 | } | |
992 | //if no errors allowed - keep start within the first clock | |
993 | if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) | |
994 | loopCnt = clk[clkCnt] * 2; | |
995 | ||
996 | bestErr[clkCnt] = 1000; | |
997 | ||
998 | //try lining up the peaks by moving starting point (try first few clocks) | |
999 | for (ii=0; ii < loopCnt; ii++){ | |
1000 | if (dest[ii] < peak && dest[ii] > low) continue; | |
1001 | ||
1002 | errCnt = 0; | |
1003 | // now that we have the first one lined up test rest of wave array | |
1004 | loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1; | |
1005 | for (i=0; i < loopEnd; ++i){ | |
1006 | arrLoc = ii + (i * clk[clkCnt]); | |
1007 | if (dest[arrLoc] >= peak || dest[arrLoc] <= low){ | |
1008 | }else if (dest[arrLoc-tol] >= peak || dest[arrLoc-tol] <= low){ | |
1009 | }else if (dest[arrLoc+tol] >= peak || dest[arrLoc+tol] <= low){ | |
1010 | }else{ //error no peak detected | |
1011 | errCnt++; | |
1012 | } | |
1013 | } | |
1014 | //if we found no errors then we can stop here and a low clock (common clocks) | |
1015 | // this is correct one - return this clock | |
1016 | if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d", clk[clkCnt], errCnt, ii, i); | |
1017 | if (errCnt==0 && clkCnt<7) { | |
1018 | if (!clockFnd) *clock = clk[clkCnt]; | |
1019 | return ii; | |
1020 | } | |
1021 | //if we found errors see if it is lowest so far and save it as best run | |
1022 | if (errCnt < bestErr[clkCnt]) { | |
1023 | bestErr[clkCnt] = errCnt; | |
1024 | bestStart[clkCnt] = ii; | |
1025 | } | |
1026 | } | |
1027 | } | |
1028 | uint8_t k; | |
1029 | uint8_t best = 0; | |
1030 | for (k=1; k < clkEnd; ++k){ | |
1031 | if (bestErr[k] < bestErr[best]){ | |
1032 | if (bestErr[k] == 0) bestErr[k]=1; | |
1033 | // current best bit to error ratio vs new bit to error ratio | |
1034 | if ( (size/clk[best])/bestErr[best] < (size/clk[k])/bestErr[k] ){ | |
1035 | best = k; | |
1036 | } | |
1037 | } | |
1038 | if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]); | |
1039 | } | |
1040 | if (!clockFnd) *clock = clk[best]; | |
1041 | return bestStart[best]; | |
1042 | } | |
1043 | ||
1044 | //by marshmellow | |
1045 | //detect psk clock by reading each phase shift | |
1046 | // a phase shift is determined by measuring the sample length of each wave | |
1047 | int DetectPSKClock(uint8_t dest[], size_t size, int clock) | |
1048 | { | |
1049 | uint8_t clk[]={255,16,32,40,50,64,100,128,255}; //255 is not a valid clock | |
1050 | uint16_t loopCnt = 4096; //don't need to loop through entire array... | |
1051 | if (size == 0) return 0; | |
1052 | if (size<loopCnt) loopCnt = size-20; | |
1053 | ||
1054 | //if we already have a valid clock quit | |
1055 | size_t i=1; | |
1056 | for (; i < 8; ++i) | |
1057 | if (clk[i] == clock) return clock; | |
1058 | ||
1059 | size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0; | |
1060 | uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1; | |
1061 | uint16_t peakcnt=0, errCnt=0, waveLenCnt=0; | |
1062 | uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; | |
1063 | uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0}; | |
1064 | fc = countFC(dest, size, 0); | |
1065 | if (fc!=2 && fc!=4 && fc!=8) return -1; | |
1066 | if (g_debugMode==2) prnt("DEBUG PSK: FC: %d",fc); | |
1067 | ||
1068 | //find first full wave | |
1069 | for (i=160; i<loopCnt; i++){ | |
1070 | if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1071 | if (waveStart == 0) { | |
1072 | waveStart = i+1; | |
1073 | //prnt("DEBUG: waveStart: %d",waveStart); | |
1074 | } else { | |
1075 | waveEnd = i+1; | |
1076 | //prnt("DEBUG: waveEnd: %d",waveEnd); | |
1077 | waveLenCnt = waveEnd-waveStart; | |
1078 | if (waveLenCnt > fc){ | |
1079 | firstFullWave = waveStart; | |
1080 | fullWaveLen=waveLenCnt; | |
1081 | break; | |
1082 | } | |
1083 | waveStart=0; | |
1084 | } | |
1085 | } | |
1086 | } | |
1087 | if (g_debugMode ==2) prnt("DEBUG PSK: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); | |
1088 | ||
1089 | //test each valid clock from greatest to smallest to see which lines up | |
1090 | for(clkCnt=7; clkCnt >= 1 ; clkCnt--){ | |
1091 | lastClkBit = firstFullWave; //set end of wave as clock align | |
1092 | waveStart = 0; | |
1093 | errCnt=0; | |
1094 | peakcnt=0; | |
1095 | if (g_debugMode == 2) prnt("DEBUG PSK: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit); | |
1096 | ||
1097 | for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){ | |
1098 | //top edge of wave = start of new wave | |
1099 | if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1100 | if (waveStart == 0) { | |
1101 | waveStart = i+1; | |
1102 | waveLenCnt=0; | |
1103 | } else { //waveEnd | |
1104 | waveEnd = i+1; | |
1105 | waveLenCnt = waveEnd-waveStart; | |
1106 | if (waveLenCnt > fc){ | |
1107 | //if this wave is a phase shift | |
1108 | 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); | |
1109 | if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit | |
1110 | peakcnt++; | |
1111 | lastClkBit+=clk[clkCnt]; | |
1112 | } else if (i<lastClkBit+8){ | |
1113 | //noise after a phase shift - ignore | |
1114 | } else { //phase shift before supposed to based on clock | |
1115 | errCnt++; | |
1116 | } | |
1117 | } else if (i+1 > lastClkBit + clk[clkCnt] + tol + fc){ | |
1118 | lastClkBit+=clk[clkCnt]; //no phase shift but clock bit | |
1119 | } | |
1120 | waveStart=i+1; | |
1121 | } | |
1122 | } | |
1123 | } | |
1124 | if (errCnt == 0){ | |
1125 | return clk[clkCnt]; | |
1126 | } | |
1127 | if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt; | |
1128 | if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt; | |
1129 | } | |
1130 | //all tested with errors | |
1131 | //return the highest clk with the most peaks found | |
1132 | uint8_t best=7; | |
1133 | for (i=7; i>=1; i--){ | |
1134 | if (peaksdet[i] > peaksdet[best]) { | |
1135 | best = i; | |
1136 | } | |
1137 | if (g_debugMode == 2) prnt("DEBUG PSK: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[i],peaksdet[i],bestErr[i],clk[best]); | |
1138 | } | |
1139 | return clk[best]; | |
1140 | } | |
1141 | ||
1142 | int DetectStrongNRZClk(uint8_t *dest, size_t size, int peak, int low){ | |
1143 | //find shortest transition from high to low | |
1144 | size_t i = 0; | |
1145 | size_t transition1 = 0; | |
1146 | int lowestTransition = 255; | |
1147 | bool lastWasHigh = false; | |
1148 | ||
1149 | //find first valid beginning of a high or low wave | |
1150 | while ((dest[i] >= peak || dest[i] <= low) && (i < size)) | |
1151 | ++i; | |
1152 | while ((dest[i] < peak && dest[i] > low) && (i < size)) | |
1153 | ++i; | |
1154 | lastWasHigh = (dest[i] >= peak); | |
1155 | ||
1156 | if (i==size) return 0; | |
1157 | transition1 = i; | |
1158 | ||
1159 | for (;i < size; i++) { | |
1160 | if ((dest[i] >= peak && !lastWasHigh) || (dest[i] <= low && lastWasHigh)) { | |
1161 | lastWasHigh = (dest[i] >= peak); | |
1162 | if (i-transition1 < lowestTransition) lowestTransition = i-transition1; | |
1163 | transition1 = i; | |
1164 | } | |
1165 | } | |
1166 | if (lowestTransition == 255) lowestTransition = 0; | |
1167 | if (g_debugMode==2) prnt("DEBUG NRZ: detectstrongNRZclk smallest wave: %d",lowestTransition); | |
1168 | return lowestTransition; | |
1169 | } | |
1170 | ||
1171 | //by marshmellow | |
1172 | //detect nrz clock by reading #peaks vs no peaks(or errors) | |
1173 | int DetectNRZClock(uint8_t dest[], size_t size, int clock) | |
1174 | { | |
1175 | size_t i=0; | |
1176 | uint8_t clk[]={8,16,32,40,50,64,100,128,255}; | |
1177 | size_t loopCnt = 4096; //don't need to loop through entire array... | |
1178 | if (size == 0) return 0; | |
1179 | if (size<loopCnt) loopCnt = size-20; | |
1180 | //if we already have a valid clock quit | |
1181 | for (; i < 8; ++i) | |
1182 | if (clk[i] == clock) return clock; | |
1183 | ||
1184 | //get high and low peak | |
1185 | int peak, low; | |
1186 | if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0; | |
1187 | ||
1188 | int lowestTransition = DetectStrongNRZClk(dest, size-20, peak, low); | |
1189 | size_t ii; | |
1190 | uint8_t clkCnt; | |
1191 | uint8_t tol = 0; | |
1192 | uint16_t smplCnt = 0; | |
1193 | int16_t peakcnt = 0; | |
1194 | int16_t peaksdet[] = {0,0,0,0,0,0,0,0}; | |
1195 | uint16_t maxPeak = 255; | |
1196 | bool firstpeak = false; | |
1197 | //test for large clipped waves | |
1198 | for (i=0; i<loopCnt; i++){ | |
1199 | if (dest[i] >= peak || dest[i] <= low){ | |
1200 | if (!firstpeak) continue; | |
1201 | smplCnt++; | |
1202 | } else { | |
1203 | firstpeak=true; | |
1204 | if (smplCnt > 6 ){ | |
1205 | if (maxPeak > smplCnt){ | |
1206 | maxPeak = smplCnt; | |
1207 | //prnt("maxPk: %d",maxPeak); | |
1208 | } | |
1209 | peakcnt++; | |
1210 | //prnt("maxPk: %d, smplCnt: %d, peakcnt: %d",maxPeak,smplCnt,peakcnt); | |
1211 | smplCnt=0; | |
1212 | } | |
1213 | } | |
1214 | } | |
1215 | bool errBitHigh = 0; | |
1216 | bool bitHigh = 0; | |
1217 | uint8_t ignoreCnt = 0; | |
1218 | uint8_t ignoreWindow = 4; | |
1219 | bool lastPeakHigh = 0; | |
1220 | int lastBit = 0; | |
1221 | peakcnt=0; | |
1222 | //test each valid clock from smallest to greatest to see which lines up | |
1223 | for(clkCnt=0; clkCnt < 8; ++clkCnt){ | |
1224 | //ignore clocks smaller than smallest peak | |
1225 | if (clk[clkCnt] < maxPeak - (clk[clkCnt]/4)) continue; | |
1226 | //try lining up the peaks by moving starting point (try first 256) | |
1227 | for (ii=20; ii < loopCnt; ++ii){ | |
1228 | if ((dest[ii] >= peak) || (dest[ii] <= low)){ | |
1229 | peakcnt=0; | |
1230 | bitHigh = false; | |
1231 | ignoreCnt = 0; | |
1232 | lastBit = ii-clk[clkCnt]; | |
1233 | //loop through to see if this start location works | |
1234 | for (i = ii; i < size-20; ++i) { | |
1235 | //if we are at a clock bit | |
1236 | if ((i >= lastBit + clk[clkCnt] - tol) && (i <= lastBit + clk[clkCnt] + tol)) { | |
1237 | //test high/low | |
1238 | if (dest[i] >= peak || dest[i] <= low) { | |
1239 | //if same peak don't count it | |
1240 | if ((dest[i] >= peak && !lastPeakHigh) || (dest[i] <= low && lastPeakHigh)) { | |
1241 | peakcnt++; | |
1242 | } | |
1243 | lastPeakHigh = (dest[i] >= peak); | |
1244 | bitHigh = true; | |
1245 | errBitHigh = false; | |
1246 | ignoreCnt = ignoreWindow; | |
1247 | lastBit += clk[clkCnt]; | |
1248 | } else if (i == lastBit + clk[clkCnt] + tol) { | |
1249 | lastBit += clk[clkCnt]; | |
1250 | } | |
1251 | //else if not a clock bit and no peaks | |
1252 | } else if (dest[i] < peak && dest[i] > low){ | |
1253 | if (ignoreCnt==0){ | |
1254 | bitHigh=false; | |
1255 | if (errBitHigh==true) peakcnt--; | |
1256 | errBitHigh=false; | |
1257 | } else { | |
1258 | ignoreCnt--; | |
1259 | } | |
1260 | // else if not a clock bit but we have a peak | |
1261 | } else if ((dest[i]>=peak || dest[i]<=low) && (!bitHigh)) { | |
1262 | //error bar found no clock... | |
1263 | errBitHigh=true; | |
1264 | } | |
1265 | } | |
1266 | if(peakcnt>peaksdet[clkCnt]) { | |
1267 | peaksdet[clkCnt]=peakcnt; | |
1268 | } | |
1269 | } | |
1270 | } | |
1271 | } | |
1272 | int iii=7; | |
1273 | uint8_t best=0; | |
1274 | for (iii=7; iii > 0; iii--){ | |
1275 | if ((peaksdet[iii] >= (peaksdet[best]-1)) && (peaksdet[iii] <= peaksdet[best]+1) && lowestTransition) { | |
1276 | if (clk[iii] > (lowestTransition - (clk[iii]/8)) && clk[iii] < (lowestTransition + (clk[iii]/8))) { | |
1277 | best = iii; | |
1278 | } | |
1279 | } else if (peaksdet[iii] > peaksdet[best]){ | |
1280 | best = iii; | |
1281 | } | |
1282 | 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); | |
1283 | } | |
1284 | ||
1285 | return clk[best]; | |
1286 | } | |
1287 | ||
1288 | // by marshmellow | |
1289 | // convert psk1 demod to psk2 demod | |
1290 | // only transition waves are 1s | |
1291 | void psk1TOpsk2(uint8_t *bits, size_t size) { | |
1292 | uint8_t lastBit = bits[0]; | |
1293 | for (size_t i = 1; i < size; i++){ | |
1294 | //ignore errors | |
1295 | if (bits[i] == 7) continue; | |
1296 | ||
1297 | if (lastBit != bits[i]){ | |
1298 | lastBit = bits[i]; | |
1299 | bits[i] = 1; | |
1300 | } else { | |
1301 | bits[i] = 0; | |
1302 | } | |
1303 | } | |
1304 | } | |
1305 | ||
1306 | // by marshmellow | |
1307 | // convert psk2 demod to psk1 demod | |
1308 | // from only transition waves are 1s to phase shifts change bit | |
1309 | void psk2TOpsk1(uint8_t *bits, size_t size) { | |
1310 | uint8_t phase = 0; | |
1311 | for (size_t i = 0; i < size; i++){ | |
1312 | if (bits[i] == 1){ | |
1313 | phase ^= 1; | |
1314 | } | |
1315 | bits[i] = phase; | |
1316 | } | |
1317 | } | |
1318 | ||
1319 | // redesigned by marshmellow adjusted from existing decode functions | |
1320 | // indala id decoding - only tested on 26 bit tags, but attempted to make it work for more | |
1321 | int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert) | |
1322 | { | |
1323 | //26 bit 40134 format (don't know other formats) | |
1324 | 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}; | |
1325 | 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}; | |
1326 | size_t startidx = 0; | |
1327 | if (!preambleSearch(bitStream, preamble, sizeof(preamble), size, &startidx)){ | |
1328 | // if didn't find preamble try again inverting | |
1329 | if (!preambleSearch(bitStream, preamble_i, sizeof(preamble_i), size, &startidx)) return -1; | |
1330 | *invert ^= 1; | |
1331 | } | |
1332 | if (*size != 64 && *size != 224) return -2; | |
1333 | if (*invert==1) | |
1334 | for (size_t i = startidx; i < *size; i++) | |
1335 | bitStream[i] ^= 1; | |
1336 | ||
1337 | return (int) startidx; | |
1338 | } | |
1339 | ||
1340 | // by marshmellow - demodulate NRZ wave - requires a read with strong signal | |
1341 | // peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak | |
1342 | int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert){ | |
1343 | if (justNoise(dest, *size)) return -1; | |
1344 | *clk = DetectNRZClock(dest, *size, *clk); | |
1345 | if (*clk==0) return -2; | |
1346 | size_t i, gLen = 4096; | |
1347 | if (gLen>*size) gLen = *size-20; | |
1348 | int high, low; | |
1349 | if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low | |
1350 | ||
1351 | uint8_t bit=0; | |
1352 | //convert wave samples to 1's and 0's | |
1353 | for(i=20; i < *size-20; i++){ | |
1354 | if (dest[i] >= high) bit = 1; | |
1355 | if (dest[i] <= low) bit = 0; | |
1356 | dest[i] = bit; | |
1357 | } | |
1358 | //now demod based on clock (rf/32 = 32 1's for one 1 bit, 32 0's for one 0 bit) | |
1359 | size_t lastBit = 0; | |
1360 | size_t numBits = 0; | |
1361 | for(i=21; i < *size-20; i++) { | |
1362 | //if transition detected or large number of same bits - store the passed bits | |
1363 | if (dest[i] != dest[i-1] || (i-lastBit) == (10 * *clk)) { | |
1364 | memset(dest+numBits, dest[i-1] ^ *invert, (i - lastBit + (*clk/4)) / *clk); | |
1365 | numBits += (i - lastBit + (*clk/4)) / *clk; | |
1366 | lastBit = i-1; | |
1367 | } | |
1368 | } | |
1369 | *size = numBits; | |
1370 | return 0; | |
1371 | } | |
1372 | ||
1373 | //by marshmellow | |
1374 | //detects the bit clock for FSK given the high and low Field Clocks | |
1375 | uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) | |
1376 | { | |
1377 | uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; | |
1378 | uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1379 | uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1380 | uint8_t rfLensFnd = 0; | |
1381 | uint8_t lastFCcnt = 0; | |
1382 | uint16_t fcCounter = 0; | |
1383 | uint16_t rfCounter = 0; | |
1384 | uint8_t firstBitFnd = 0; | |
1385 | size_t i; | |
1386 | if (size == 0) return 0; | |
1387 | ||
1388 | uint8_t fcTol = ((fcHigh*100 - fcLow*100)/2 + 50)/100; //(uint8_t)(0.5+(float)(fcHigh-fcLow)/2); | |
1389 | rfLensFnd=0; | |
1390 | fcCounter=0; | |
1391 | rfCounter=0; | |
1392 | firstBitFnd=0; | |
1393 | //prnt("DEBUG: fcTol: %d",fcTol); | |
1394 | // prime i to first peak / up transition | |
1395 | for (i = 160; i < size-20; i++) | |
1396 | if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) | |
1397 | break; | |
1398 | ||
1399 | for (; i < size-20; i++){ | |
1400 | fcCounter++; | |
1401 | rfCounter++; | |
1402 | ||
1403 | if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1]) | |
1404 | continue; | |
1405 | // else new peak | |
1406 | // if we got less than the small fc + tolerance then set it to the small fc | |
1407 | // if it is inbetween set it to the last counter | |
1408 | if (fcCounter < fcHigh && fcCounter > fcLow) | |
1409 | fcCounter = lastFCcnt; | |
1410 | else if (fcCounter < fcLow+fcTol) | |
1411 | fcCounter = fcLow; | |
1412 | else //set it to the large fc | |
1413 | fcCounter = fcHigh; | |
1414 | ||
1415 | //look for bit clock (rf/xx) | |
1416 | if ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){ | |
1417 | //not the same size as the last wave - start of new bit sequence | |
1418 | if (firstBitFnd > 1){ //skip first wave change - probably not a complete bit | |
1419 | for (int ii=0; ii<15; ii++){ | |
1420 | if (rfLens[ii] >= (rfCounter-4) && rfLens[ii] <= (rfCounter+4)){ | |
1421 | rfCnts[ii]++; | |
1422 | rfCounter = 0; | |
1423 | break; | |
1424 | } | |
1425 | } | |
1426 | if (rfCounter > 0 && rfLensFnd < 15){ | |
1427 | //prnt("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); | |
1428 | rfCnts[rfLensFnd]++; | |
1429 | rfLens[rfLensFnd++] = rfCounter; | |
1430 | } | |
1431 | } else { | |
1432 | firstBitFnd++; | |
1433 | } | |
1434 | rfCounter=0; | |
1435 | lastFCcnt=fcCounter; | |
1436 | } | |
1437 | fcCounter=0; | |
1438 | } | |
1439 | uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; | |
1440 | ||
1441 | for (i=0; i<15; i++){ | |
1442 | //get highest 2 RF values (might need to get more values to compare or compare all?) | |
1443 | if (rfCnts[i]>rfCnts[rfHighest]){ | |
1444 | rfHighest3=rfHighest2; | |
1445 | rfHighest2=rfHighest; | |
1446 | rfHighest=i; | |
1447 | } else if(rfCnts[i]>rfCnts[rfHighest2]){ | |
1448 | rfHighest3=rfHighest2; | |
1449 | rfHighest2=i; | |
1450 | } else if(rfCnts[i]>rfCnts[rfHighest3]){ | |
1451 | rfHighest3=i; | |
1452 | } | |
1453 | if (g_debugMode==2) prnt("DEBUG FSK: RF %d, cnts %d",rfLens[i], rfCnts[i]); | |
1454 | } | |
1455 | // set allowed clock remainder tolerance to be 1 large field clock length+1 | |
1456 | // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off | |
1457 | uint8_t tol1 = fcHigh+1; | |
1458 | ||
1459 | if (g_debugMode==2) prnt("DEBUG FSK: most counted rf values: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); | |
1460 | ||
1461 | // loop to find the highest clock that has a remainder less than the tolerance | |
1462 | // compare samples counted divided by | |
1463 | // test 128 down to 32 (shouldn't be possible to have fc/10 & fc/8 and rf/16 or less) | |
1464 | int ii=7; | |
1465 | for (; ii>=2; ii--){ | |
1466 | if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ | |
1467 | if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ | |
1468 | if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ | |
1469 | if (g_debugMode==2) prnt("DEBUG FSK: clk %d divides into the 3 most rf values within tolerance",clk[ii]); | |
1470 | break; | |
1471 | } | |
1472 | } | |
1473 | } | |
1474 | } | |
1475 | ||
1476 | if (ii<2) return 0; // oops we went too far | |
1477 | ||
1478 | return clk[ii]; | |
1479 | } | |
1480 | ||
1481 | //by marshmellow | |
1482 | //countFC is to detect the field clock lengths. | |
1483 | //counts and returns the 2 most common wave lengths | |
1484 | //mainly used for FSK field clock detection | |
1485 | uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) | |
1486 | { | |
1487 | uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1488 | uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1489 | uint8_t fcLensFnd = 0; | |
1490 | uint8_t lastFCcnt = 0; | |
1491 | uint8_t fcCounter = 0; | |
1492 | size_t i; | |
1493 | if (size < 180) return 0; | |
1494 | ||
1495 | // prime i to first up transition | |
1496 | for (i = 160; i < size-20; i++) | |
1497 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) | |
1498 | break; | |
1499 | ||
1500 | for (; i < size-20; i++){ | |
1501 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ | |
1502 | // new up transition | |
1503 | fcCounter++; | |
1504 | if (fskAdj){ | |
1505 | //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) | |
1506 | if (lastFCcnt==5 && fcCounter==9) fcCounter--; | |
1507 | //if fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5) | |
1508 | if ((fcCounter==9) || fcCounter==4) fcCounter++; | |
1509 | // save last field clock count (fc/xx) | |
1510 | lastFCcnt = fcCounter; | |
1511 | } | |
1512 | // find which fcLens to save it to: | |
1513 | for (int ii=0; ii<15; ii++){ | |
1514 | if (fcLens[ii]==fcCounter){ | |
1515 | fcCnts[ii]++; | |
1516 | fcCounter=0; | |
1517 | break; | |
1518 | } | |
1519 | } | |
1520 | if (fcCounter>0 && fcLensFnd<15){ | |
1521 | //add new fc length | |
1522 | fcCnts[fcLensFnd]++; | |
1523 | fcLens[fcLensFnd++]=fcCounter; | |
1524 | } | |
1525 | fcCounter=0; | |
1526 | } else { | |
1527 | // count sample | |
1528 | fcCounter++; | |
1529 | } | |
1530 | } | |
1531 | ||
1532 | uint8_t best1=14, best2=14, best3=14; | |
1533 | uint16_t maxCnt1=0; | |
1534 | // go through fclens and find which ones are bigest 2 | |
1535 | for (i=0; i<15; i++){ | |
1536 | // get the 3 best FC values | |
1537 | if (fcCnts[i]>maxCnt1) { | |
1538 | best3=best2; | |
1539 | best2=best1; | |
1540 | maxCnt1=fcCnts[i]; | |
1541 | best1=i; | |
1542 | } else if(fcCnts[i]>fcCnts[best2]){ | |
1543 | best3=best2; | |
1544 | best2=i; | |
1545 | } else if(fcCnts[i]>fcCnts[best3]){ | |
1546 | best3=i; | |
1547 | } | |
1548 | 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]); | |
1549 | } | |
1550 | if (fcLens[best1]==0) return 0; | |
1551 | uint8_t fcH=0, fcL=0; | |
1552 | if (fcLens[best1]>fcLens[best2]){ | |
1553 | fcH=fcLens[best1]; | |
1554 | fcL=fcLens[best2]; | |
1555 | } else{ | |
1556 | fcH=fcLens[best2]; | |
1557 | fcL=fcLens[best1]; | |
1558 | } | |
1559 | if ((size-180)/fcH/3 > fcCnts[best1]+fcCnts[best2]) { | |
1560 | 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]); | |
1561 | return 0; //lots of waves not psk or fsk | |
1562 | } | |
1563 | // TODO: take top 3 answers and compare to known Field clocks to get top 2 | |
1564 | ||
1565 | uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; | |
1566 | if (fskAdj) return fcs; | |
1567 | return fcLens[best1]; | |
1568 | } | |
1569 | ||
1570 | //by marshmellow - demodulate PSK1 wave | |
1571 | //uses wave lengths (# Samples) | |
1572 | int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) | |
1573 | { | |
1574 | if (size == 0) return -1; | |
1575 | uint16_t loopCnt = 4096; //don't need to loop through entire array... | |
1576 | if (*size<loopCnt) loopCnt = *size; | |
1577 | ||
1578 | size_t numBits=0; | |
1579 | uint8_t curPhase = *invert; | |
1580 | size_t i=0, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0; | |
1581 | uint16_t fc=0, fullWaveLen=0, tol=1; | |
1582 | uint16_t errCnt=0, waveLenCnt=0, errCnt2=0; | |
1583 | fc = countFC(dest, *size, 1); | |
1584 | uint8_t fc2 = fc >> 8; | |
1585 | if (fc2 == 10) return -1; //fsk found - quit | |
1586 | fc = fc & 0xFF; | |
1587 | if (fc!=2 && fc!=4 && fc!=8) return -1; | |
1588 | //prnt("DEBUG: FC: %d",fc); | |
1589 | *clock = DetectPSKClock(dest, *size, *clock); | |
1590 | if (*clock == 0) return -1; | |
1591 | ||
1592 | //find start of modulating data in trace | |
1593 | uint8_t threshold_value = 123; //-5 | |
1594 | i = findModStart(dest, *size, threshold_value, fc); | |
1595 | ||
1596 | //find first phase shift | |
1597 | int avgWaveVal=0, lastAvgWaveVal=0; | |
1598 | waveStart = i; | |
1599 | for (; i<loopCnt; i++){ | |
1600 | // find peak | |
1601 | if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1602 | waveEnd = i+1; | |
1603 | if (g_debugMode == 2) prnt("DEBUG PSK: waveEnd: %u, waveStart: %u",waveEnd, waveStart); | |
1604 | waveLenCnt = waveEnd-waveStart; | |
1605 | if (waveLenCnt > fc && waveStart > fc && !(waveLenCnt > fc+3)){ //not first peak and is a large wave but not out of whack | |
1606 | lastAvgWaveVal = avgWaveVal/(waveLenCnt); | |
1607 | firstFullWave = waveStart; | |
1608 | fullWaveLen=waveLenCnt; | |
1609 | //if average wave value is > graph 0 then it is an up wave or a 1 (could cause inverting) | |
1610 | if (lastAvgWaveVal > threshold_value) curPhase ^= 1; | |
1611 | break; | |
1612 | } | |
1613 | waveStart = i+1; | |
1614 | avgWaveVal = 0; | |
1615 | } | |
1616 | avgWaveVal += dest[i+2]; | |
1617 | } | |
1618 | if (firstFullWave == 0) { | |
1619 | // no phase shift detected - could be all 1's or 0's - doesn't matter where we start | |
1620 | // so skip a little to ensure we are past any Start Signal | |
1621 | firstFullWave = 160; | |
1622 | memset(dest, curPhase, firstFullWave / *clock); | |
1623 | } else { | |
1624 | memset(dest, curPhase^1, firstFullWave / *clock); | |
1625 | } | |
1626 | //advance bits | |
1627 | numBits += (firstFullWave / *clock); | |
1628 | //set start of wave as clock align | |
1629 | lastClkBit = firstFullWave; | |
1630 | if (g_debugMode==2) prnt("DEBUG PSK: firstFullWave: %u, waveLen: %u",firstFullWave,fullWaveLen); | |
1631 | if (g_debugMode==2) prnt("DEBUG PSK: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc); | |
1632 | waveStart = 0; | |
1633 | dest[numBits++] = curPhase; //set first read bit | |
1634 | for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){ | |
1635 | //top edge of wave = start of new wave | |
1636 | if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1637 | if (waveStart == 0) { | |
1638 | waveStart = i+1; | |
1639 | waveLenCnt = 0; | |
1640 | avgWaveVal = dest[i+1]; | |
1641 | } else { //waveEnd | |
1642 | waveEnd = i+1; | |
1643 | waveLenCnt = waveEnd-waveStart; | |
1644 | lastAvgWaveVal = avgWaveVal/waveLenCnt; | |
1645 | if (waveLenCnt > fc){ | |
1646 | //prnt("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal); | |
1647 | //this wave is a phase shift | |
1648 | //prnt("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc); | |
1649 | if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit | |
1650 | curPhase ^= 1; | |
1651 | dest[numBits++] = curPhase; | |
1652 | lastClkBit += *clock; | |
1653 | } else if (i < lastClkBit+10+fc){ | |
1654 | //noise after a phase shift - ignore | |
1655 | } else { //phase shift before supposed to based on clock | |
1656 | errCnt++; | |
1657 | dest[numBits++] = 7; | |
1658 | } | |
1659 | } else if (i+1 > lastClkBit + *clock + tol + fc){ | |
1660 | lastClkBit += *clock; //no phase shift but clock bit | |
1661 | dest[numBits++] = curPhase; | |
1662 | } else if (waveLenCnt < fc - 1) { //wave is smaller than field clock (shouldn't happen often) | |
1663 | errCnt2++; | |
1664 | if(errCnt2 > 101) return errCnt2; | |
1665 | } | |
1666 | avgWaveVal = 0; | |
1667 | waveStart = i+1; | |
1668 | } | |
1669 | } | |
1670 | avgWaveVal += dest[i+1]; | |
1671 | } | |
1672 | *size = numBits; | |
1673 | return errCnt; | |
1674 | } | |
1675 | ||
1676 | //by marshmellow | |
1677 | //attempt to identify a Sequence Terminator in ASK modulated raw wave | |
1678 | bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) { | |
1679 | size_t bufsize = *size; | |
1680 | //need to loop through all samples and identify our clock, look for the ST pattern | |
1681 | uint8_t fndClk[] = {8,16,32,40,50,64,128}; | |
1682 | int clk = 0; | |
1683 | int tol = 0; | |
1684 | int i, j, skip, start, end, low, high, minClk, waveStart; | |
1685 | bool complete = false; | |
1686 | int tmpbuff[bufsize / 32]; //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured | |
1687 | int waveLen[bufsize / 32]; // if clock is larger then we waste memory in array size that is not needed... | |
1688 | size_t testsize = (bufsize < 512) ? bufsize : 512; | |
1689 | int phaseoff = 0; | |
1690 | high = low = 128; | |
1691 | memset(tmpbuff, 0, sizeof(tmpbuff)); | |
1692 | memset(waveLen, 0, sizeof(waveLen)); | |
1693 | ||
1694 | ||
1695 | if ( getHiLo(buffer, testsize, &high, &low, 80, 80) == -1 ) { | |
1696 | if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting"); | |
1697 | return false; //just noise | |
1698 | } | |
1699 | i = 0; | |
1700 | j = 0; | |
1701 | minClk = 255; | |
1702 | // get to first full low to prime loop and skip incomplete first pulse | |
1703 | while ((buffer[i] < high) && (i < bufsize)) | |
1704 | ++i; | |
1705 | while ((buffer[i] > low) && (i < bufsize)) | |
1706 | ++i; | |
1707 | skip = i; | |
1708 | ||
1709 | // populate tmpbuff buffer with pulse lengths | |
1710 | while (i < bufsize) { | |
1711 | // measure from low to low | |
1712 | while ((buffer[i] > low) && (i < bufsize)) | |
1713 | ++i; | |
1714 | start= i; | |
1715 | while ((buffer[i] < high) && (i < bufsize)) | |
1716 | ++i; | |
1717 | //first high point for this wave | |
1718 | waveStart = i; | |
1719 | while ((buffer[i] > low) && (i < bufsize)) | |
1720 | ++i; | |
1721 | if (j >= (bufsize/32)) { | |
1722 | break; | |
1723 | } | |
1724 | waveLen[j] = i - waveStart; //first high to first low | |
1725 | tmpbuff[j++] = i - start; | |
1726 | if (i-start < minClk && i < bufsize) { | |
1727 | minClk = i - start; | |
1728 | } | |
1729 | } | |
1730 | // set clock - might be able to get this externally and remove this work... | |
1731 | if (!clk) { | |
1732 | for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { | |
1733 | tol = fndClk[clkCnt]/8; | |
1734 | if (minClk >= fndClk[clkCnt]-tol && minClk <= fndClk[clkCnt]+1) { | |
1735 | clk=fndClk[clkCnt]; | |
1736 | break; | |
1737 | } | |
1738 | } | |
1739 | // clock not found - ERROR | |
1740 | if (!clk) { | |
1741 | if (g_debugMode==2) prnt("DEBUG STT: clock not found - quitting"); | |
1742 | return false; | |
1743 | } | |
1744 | } else tol = clk/8; | |
1745 | ||
1746 | *foundclock = clk; | |
1747 | ||
1748 | // look for Sequence Terminator - should be pulses of clk*(1 or 1.5), clk*2, clk*(1.5 or 2) | |
1749 | start = -1; | |
1750 | for (i = 0; i < j - 4; ++i) { | |
1751 | skip += tmpbuff[i]; | |
1752 | if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior | |
1753 | 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 | |
1754 | 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 | |
1755 | if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit | |
1756 | start = i + 3; | |
1757 | break; | |
1758 | } | |
1759 | } | |
1760 | } | |
1761 | } | |
1762 | } | |
1763 | // first ST not found - ERROR | |
1764 | if (start < 0) { | |
1765 | if (g_debugMode==2) prnt("DEBUG STT: first STT not found - quitting"); | |
1766 | return false; | |
1767 | } else { | |
1768 | if (g_debugMode==2) prnt("DEBUG STT: first STT found at: %d, j=%d",start, j); | |
1769 | } | |
1770 | if (waveLen[i+2] > clk*1+tol) | |
1771 | phaseoff = 0; | |
1772 | else | |
1773 | phaseoff = clk/2; | |
1774 | ||
1775 | // skip over the remainder of ST | |
1776 | skip += clk*7/2; //3.5 clocks from tmpbuff[i] = end of st - also aligns for ending point | |
1777 | ||
1778 | // now do it again to find the end | |
1779 | end = skip; | |
1780 | for (i += 3; i < j - 4; ++i) { | |
1781 | end += tmpbuff[i]; | |
1782 | if (tmpbuff[i] >= clk*1-tol && tmpbuff[i] <= (clk*2)+tol && waveLen[i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior | |
1783 | 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 | |
1784 | 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 | |
1785 | if (tmpbuff[i+3] >= clk*1-tol && tmpbuff[i+3] <= clk*2+tol) { //1 to 2 clocks for end of ST + first bit | |
1786 | complete = true; | |
1787 | break; | |
1788 | } | |
1789 | } | |
1790 | } | |
1791 | } | |
1792 | } | |
1793 | end -= phaseoff; | |
1794 | //didn't find second ST - ERROR | |
1795 | if (!complete) { | |
1796 | if (g_debugMode==2) prnt("DEBUG STT: second STT not found - quitting"); | |
1797 | return false; | |
1798 | } | |
1799 | 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); | |
1800 | //now begin to trim out ST so we can use normal demod cmds | |
1801 | start = skip; | |
1802 | size_t datalen = end - start; | |
1803 | // check validity of datalen (should be even clock increments) - use a tolerance of up to 1/8th a clock | |
1804 | if ( clk - (datalen % clk) <= clk/8) { | |
1805 | // padd the amount off - could be problematic... but shouldn't happen often | |
1806 | datalen += clk - (datalen % clk); | |
1807 | } else if ( (datalen % clk) <= clk/8 ) { | |
1808 | // padd the amount off - could be problematic... but shouldn't happen often | |
1809 | datalen -= datalen % clk; | |
1810 | } else { | |
1811 | if (g_debugMode==2) prnt("DEBUG STT: datalen not divisible by clk: %u %% %d = %d - quitting", datalen, clk, datalen % clk); | |
1812 | return false; | |
1813 | } | |
1814 | // if datalen is less than one t55xx block - ERROR | |
1815 | if (datalen/clk < 8*4) { | |
1816 | if (g_debugMode==2) prnt("DEBUG STT: datalen is less than 1 full t55xx block - quitting"); | |
1817 | return false; | |
1818 | } | |
1819 | size_t dataloc = start; | |
1820 | if (buffer[dataloc-(clk*4)-(clk/8)] <= low && buffer[dataloc] <= low && buffer[dataloc-(clk*4)] >= high) { | |
1821 | //we have low drift (and a low just before the ST and a low just after the ST) - compensate by backing up the start | |
1822 | for ( i=0; i <= (clk/8); ++i ) { | |
1823 | if ( buffer[dataloc - (clk*4) - i] <= low ) { | |
1824 | dataloc -= i; | |
1825 | break; | |
1826 | } | |
1827 | } | |
1828 | } | |
1829 | ||
1830 | size_t newloc = 0; | |
1831 | i=0; | |
1832 | if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen); | |
1833 | ||
1834 | // warning - overwriting buffer given with raw wave data with ST removed... | |
1835 | while ( dataloc < bufsize-(clk/2) ) { | |
1836 | //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) | |
1837 | if (buffer[dataloc]<high && buffer[dataloc]>low && buffer[dataloc+3]<high && buffer[dataloc+3]>low) { | |
1838 | for(i=0; i < clk/2-tol; ++i) { | |
1839 | buffer[dataloc+i] = high+5; | |
1840 | } | |
1841 | } | |
1842 | for (i=0; i<datalen; ++i) { | |
1843 | if (i+newloc < bufsize) { | |
1844 | if (i+newloc < dataloc) | |
1845 | buffer[i+newloc] = buffer[dataloc]; | |
1846 | ||
1847 | dataloc++; | |
1848 | } | |
1849 | } | |
1850 | newloc += i; | |
1851 | //skip next ST - we just assume it will be there from now on... | |
1852 | if (g_debugMode==2) prnt("DEBUG STT: skipping STT at %d to %d", dataloc, dataloc+(clk*4)); | |
1853 | dataloc += clk*4; | |
1854 | } | |
1855 | *size = newloc; | |
1856 | return true; | |
1857 | } |