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eb191de6 | 1 | //----------------------------------------------------------------------------- |
ba1a299c | 2 | // Copyright (C) 2014 |
eb191de6 | 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 | //----------------------------------------------------------------------------- | |
1e090a61 | 8 | // Low frequency demod/decode commands |
eb191de6 | 9 | //----------------------------------------------------------------------------- |
10 | ||
eb191de6 | 11 | #include <stdlib.h> |
12 | #include <string.h> | |
eb191de6 | 13 | #include "lfdemod.h" |
a1d17964 | 14 | uint8_t justNoise(uint8_t *BitStream, size_t size) |
15 | { | |
16 | static const uint8_t THRESHOLD = 123; | |
17 | //test samples are not just noise | |
18 | uint8_t justNoise1 = 1; | |
19 | for(size_t idx=0; idx < size && justNoise1 ;idx++){ | |
20 | justNoise1 = BitStream[idx] < THRESHOLD; | |
21 | } | |
22 | return justNoise1; | |
23 | } | |
24 | ||
1e090a61 | 25 | //by marshmellow |
872e3d4d | 26 | //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 |
1e090a61 | 27 | int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo) |
28 | { | |
29 | *high=0; | |
30 | *low=255; | |
31 | // get high and low thresholds | |
2eec55c8 | 32 | for (size_t i=0; i < size; i++){ |
1e090a61 | 33 | if (BitStream[i] > *high) *high = BitStream[i]; |
34 | if (BitStream[i] < *low) *low = BitStream[i]; | |
35 | } | |
36 | if (*high < 123) return -1; // just noise | |
75cbbe9a | 37 | *high = ((*high-128)*fuzzHi + 12800)/100; |
38 | *low = ((*low-128)*fuzzLo + 12800)/100; | |
1e090a61 | 39 | return 1; |
40 | } | |
41 | ||
a1d17964 | 42 | // by marshmellow |
43 | // pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType | |
44 | // returns 1 if passed | |
45 | uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) | |
46 | { | |
47 | uint8_t ans = 0; | |
48 | for (uint8_t i = 0; i < bitLen; i++){ | |
49 | ans ^= ((bits >> i) & 1); | |
50 | } | |
f3bf15e4 | 51 | //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); |
a1d17964 | 52 | return (ans == pType); |
53 | } | |
54 | ||
55 | //by marshmellow | |
2147c307 | 56 | //search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length |
a1d17964 | 57 | uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx) |
58 | { | |
e0165dcf | 59 | uint8_t foundCnt=0; |
60 | for (int idx=0; idx < *size - pLen; idx++){ | |
61 | if (memcmp(BitStream+idx, preamble, pLen) == 0){ | |
62 | //first index found | |
63 | foundCnt++; | |
64 | if (foundCnt == 1){ | |
65 | *startIdx = idx; | |
66 | } | |
67 | if (foundCnt == 2){ | |
68 | *size = idx - *startIdx; | |
69 | return 1; | |
70 | } | |
71 | } | |
72 | } | |
73 | return 0; | |
a1d17964 | 74 | } |
75 | ||
2147c307 | 76 | //by marshmellow |
77 | //takes 1s and 0s and searches for EM410x format - output EM ID | |
78 | uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) | |
79 | { | |
e0165dcf | 80 | //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future |
81 | // otherwise could be a void with no arguments | |
82 | //set defaults | |
83 | uint32_t i = 0; | |
2767fc02 | 84 | if (BitStream[1]>1) return 0; //allow only 1s and 0s |
85 | ||
e0165dcf | 86 | // 111111111 bit pattern represent start of frame |
87 | // include 0 in front to help get start pos | |
88 | uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1}; | |
89 | uint32_t idx = 0; | |
90 | uint32_t parityBits = 0; | |
91 | uint8_t errChk = 0; | |
92 | uint8_t FmtLen = 10; | |
93 | *startIdx = 0; | |
94 | errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); | |
95 | if (errChk == 0 || *size < 64) return 0; | |
96 | if (*size > 64) FmtLen = 22; | |
97 | *startIdx += 1; //get rid of 0 from preamble | |
98 | idx = *startIdx + 9; | |
99 | for (i=0; i<FmtLen; i++){ //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits) | |
100 | parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5); | |
2eec55c8 | 101 | //check even parity - quit if failed |
102 | if (parityTest(parityBits, 5, 0) == 0) return 0; | |
e0165dcf | 103 | //set uint64 with ID from BitStream |
104 | for (uint8_t ii=0; ii<4; ii++){ | |
105 | *hi = (*hi << 1) | (*lo >> 63); | |
106 | *lo = (*lo << 1) | (BitStream[(i*5)+ii+idx]); | |
107 | } | |
108 | } | |
109 | if (errChk != 0) return 1; | |
110 | //skip last 5 bit parity test for simplicity. | |
111 | // *size = 64 | 128; | |
112 | return 0; | |
2147c307 | 113 | } |
114 | ||
23f0a7d8 | 115 | // demodulates strong heavily clipped samples |
116 | int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low) | |
117 | { | |
118 | size_t bitCnt=0, smplCnt=0, errCnt=0; | |
119 | uint8_t waveHigh = 0; | |
23f0a7d8 | 120 | for (size_t i=0; i < *size; i++){ |
121 | if (BinStream[i] >= high && waveHigh){ | |
122 | smplCnt++; | |
123 | } else if (BinStream[i] <= low && !waveHigh){ | |
124 | smplCnt++; | |
125 | } else { //transition | |
126 | if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){ | |
127 | if (smplCnt > clk-(clk/4)-1) { //full clock | |
128 | if (smplCnt > clk + (clk/4)+1) { //too many samples | |
129 | errCnt++; | |
2767fc02 | 130 | BinStream[bitCnt++]=7; |
23f0a7d8 | 131 | } else if (waveHigh) { |
132 | BinStream[bitCnt++] = invert; | |
133 | BinStream[bitCnt++] = invert; | |
134 | } else if (!waveHigh) { | |
135 | BinStream[bitCnt++] = invert ^ 1; | |
136 | BinStream[bitCnt++] = invert ^ 1; | |
137 | } | |
138 | waveHigh ^= 1; | |
139 | smplCnt = 0; | |
140 | } else if (smplCnt > (clk/2) - (clk/4)-1) { | |
141 | if (waveHigh) { | |
142 | BinStream[bitCnt++] = invert; | |
143 | } else if (!waveHigh) { | |
144 | BinStream[bitCnt++] = invert ^ 1; | |
145 | } | |
146 | waveHigh ^= 1; | |
147 | smplCnt = 0; | |
148 | } else if (!bitCnt) { | |
149 | //first bit | |
150 | waveHigh = (BinStream[i] >= high); | |
151 | smplCnt = 1; | |
152 | } else { | |
153 | smplCnt++; | |
154 | //transition bit oops | |
155 | } | |
156 | } else { //haven't hit new high or new low yet | |
157 | smplCnt++; | |
158 | } | |
159 | } | |
160 | } | |
161 | *size = bitCnt; | |
162 | return errCnt; | |
163 | } | |
164 | ||
eb191de6 | 165 | //by marshmellow |
6de43508 | 166 | //takes 3 arguments - clock, invert, maxErr as integers |
ba1a299c | 167 | //attempts to demodulate ask while decoding manchester |
eb191de6 | 168 | //prints binary found and saves in graphbuffer for further commands |
6de43508 | 169 | int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr) |
eb191de6 | 170 | { |
2eec55c8 | 171 | size_t i; |
6e984446 | 172 | int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default |
2eec55c8 | 173 | if (*clk==0 || start < 0) return -3; |
174 | if (*invert != 1) *invert=0; | |
175 | uint8_t initLoopMax = 255; | |
176 | if (initLoopMax > *size) initLoopMax = *size; | |
ba1a299c | 177 | // Detect high and lows |
1e090a61 | 178 | // 25% fuzz in case highs and lows aren't clipped [marshmellow] |
2eec55c8 | 179 | int high, low; |
180 | if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) return -2; //just noise | |
ba1a299c | 181 | |
23f0a7d8 | 182 | // if clean clipped waves detected run alternate demod |
183 | if (DetectCleanAskWave(BinStream, *size, high, low)) { | |
184 | cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); | |
185 | return manrawdecode(BinStream, size); | |
186 | } | |
187 | ||
1e090a61 | 188 | // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); |
6e984446 | 189 | int lastBit; //set first clock check |
2eec55c8 | 190 | uint16_t bitnum = 0; //output counter |
191 | 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 | |
192 | 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 | |
2eec55c8 | 193 | uint16_t errCnt = 0, MaxBits = 512; |
6e984446 | 194 | lastBit = start - *clk; |
195 | for (i = start; i < *size; ++i) { | |
2eec55c8 | 196 | if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ |
197 | //high found and we are expecting a bar | |
198 | lastBit += *clk; | |
199 | BinStream[bitnum++] = *invert; | |
200 | } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ | |
201 | //low found and we are expecting a bar | |
202 | lastBit += *clk; | |
203 | BinStream[bitnum++] = *invert ^ 1; | |
204 | } else if ((i-lastBit)>(*clk+tol)){ | |
205 | //should have hit a high or low based on clock!! | |
206 | //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); | |
207 | if (bitnum > 0) { | |
2767fc02 | 208 | BinStream[bitnum++] = 7; |
2eec55c8 | 209 | errCnt++; |
210 | } | |
211 | lastBit += *clk;//skip over error | |
212 | } | |
213 | if (bitnum >= MaxBits) break; | |
ba1a299c | 214 | } |
2eec55c8 | 215 | *size = bitnum; |
6e984446 | 216 | return errCnt; |
eb191de6 | 217 | } |
218 | ||
ec75f5c1 | 219 | //by marshmellow |
220 | //encode binary data into binary manchester | |
221 | int ManchesterEncode(uint8_t *BitStream, size_t size) | |
222 | { | |
223 | size_t modIdx=20000, i=0; | |
224 | if (size>modIdx) return -1; | |
f3bf15e4 | 225 | for (size_t idx=0; idx < size; idx++){ |
226 | BitStream[idx+modIdx++] = BitStream[idx]; | |
227 | BitStream[idx+modIdx++] = BitStream[idx]^1; | |
228 | } | |
229 | for (; i<(size*2); i++){ | |
230 | BitStream[i] = BitStream[i+20000]; | |
231 | } | |
232 | return i; | |
ec75f5c1 | 233 | } |
234 | ||
eb191de6 | 235 | //by marshmellow |
236 | //take 10 and 01 and manchester decode | |
237 | //run through 2 times and take least errCnt | |
ba1a299c | 238 | int manrawdecode(uint8_t * BitStream, size_t *size) |
eb191de6 | 239 | { |
13d77ef9 | 240 | uint16_t bitnum=0, MaxBits = 512, errCnt = 0; |
241 | size_t i, ii; | |
242 | uint16_t bestErr = 1000, bestRun = 0; | |
6de43508 | 243 | if (size == 0) return -1; |
2767fc02 | 244 | //find correct start position [alignment] |
13d77ef9 | 245 | for (ii=0;ii<2;++ii){ |
2eec55c8 | 246 | for (i=ii; i<*size-2; i+=2) |
247 | if (BitStream[i]==BitStream[i+1]) | |
ba1a299c | 248 | errCnt++; |
2eec55c8 | 249 | |
ba1a299c | 250 | if (bestErr>errCnt){ |
251 | bestErr=errCnt; | |
252 | bestRun=ii; | |
253 | } | |
254 | errCnt=0; | |
255 | } | |
2767fc02 | 256 | //decode |
23f0a7d8 | 257 | for (i=bestRun; i < *size-2; i+=2){ |
258 | if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ | |
259 | BitStream[bitnum++]=0; | |
260 | } else if((BitStream[i] == 0) && BitStream[i+1] == 1){ | |
261 | BitStream[bitnum++]=1; | |
262 | } else { | |
2767fc02 | 263 | BitStream[bitnum++]=7; |
ba1a299c | 264 | } |
23f0a7d8 | 265 | if(bitnum>MaxBits) break; |
ba1a299c | 266 | } |
23f0a7d8 | 267 | *size=bitnum; |
2eec55c8 | 268 | return bestErr; |
f822a063 | 269 | } |
270 | ||
f822a063 | 271 | //by marshmellow |
2147c307 | 272 | //take 01 or 10 = 1 and 11 or 00 = 0 |
273 | //check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010 | |
13d77ef9 | 274 | //decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding |
1e090a61 | 275 | int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) |
f822a063 | 276 | { |
2eec55c8 | 277 | uint16_t bitnum = 0; |
278 | uint16_t errCnt = 0; | |
279 | size_t i = offset; | |
2147c307 | 280 | uint16_t MaxBits=512; |
281 | //if not enough samples - error | |
282 | if (*size < 51) return -1; | |
283 | //check for phase change faults - skip one sample if faulty | |
284 | uint8_t offsetA = 1, offsetB = 1; | |
285 | for (; i<48; i+=2){ | |
286 | if (BitStream[i+1]==BitStream[i+2]) offsetA=0; | |
287 | if (BitStream[i+2]==BitStream[i+3]) offsetB=0; | |
288 | } | |
289 | if (!offsetA && offsetB) offset++; | |
290 | for (i=offset; i<*size-3; i+=2){ | |
291 | //check for phase error | |
13d77ef9 | 292 | if (BitStream[i+1]==BitStream[i+2]) { |
2767fc02 | 293 | BitStream[bitnum++]=7; |
2147c307 | 294 | errCnt++; |
295 | } | |
ba1a299c | 296 | if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){ |
1e090a61 | 297 | BitStream[bitnum++]=1^invert; |
ba1a299c | 298 | } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){ |
1e090a61 | 299 | BitStream[bitnum++]=invert; |
ba1a299c | 300 | } else { |
2767fc02 | 301 | BitStream[bitnum++]=7; |
ba1a299c | 302 | errCnt++; |
303 | } | |
6de43508 | 304 | if(bitnum>MaxBits) break; |
ba1a299c | 305 | } |
306 | *size=bitnum; | |
307 | return errCnt; | |
eb191de6 | 308 | } |
309 | ||
310 | //by marshmellow | |
6de43508 | 311 | void askAmp(uint8_t *BitStream, size_t size) |
312 | { | |
f3bf15e4 | 313 | int shift = 127; |
314 | int shiftedVal=0; | |
2eec55c8 | 315 | for(size_t i = 1; i<size; i++){ |
f3bf15e4 | 316 | if (BitStream[i]-BitStream[i-1]>=30) //large jump up |
317 | shift=127; | |
318 | else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down | |
319 | shift=-127; | |
320 | ||
321 | shiftedVal=BitStream[i]+shift; | |
322 | ||
323 | if (shiftedVal>255) | |
324 | shiftedVal=255; | |
325 | else if (shiftedVal<0) | |
326 | shiftedVal=0; | |
327 | BitStream[i-1] = shiftedVal; | |
328 | } | |
329 | return; | |
6de43508 | 330 | } |
331 | ||
332 | //by marshmellow | |
333 | //takes 3 arguments - clock, invert and maxErr as integers | |
eb191de6 | 334 | //attempts to demodulate ask only |
6de43508 | 335 | int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp) |
eb191de6 | 336 | { |
6de43508 | 337 | if (*size==0) return -1; |
6e984446 | 338 | int start = DetectASKClock(BinStream, *size, clk, maxErr); //clock default |
2eec55c8 | 339 | if (*clk==0 || start < 0) return -1; |
340 | if (*invert != 1) *invert = 0; | |
13d77ef9 | 341 | if (amp==1) askAmp(BinStream, *size); |
342 | ||
2eec55c8 | 343 | uint8_t initLoopMax = 255; |
6e984446 | 344 | if (initLoopMax > *size) initLoopMax = *size; |
ba1a299c | 345 | // Detect high and lows |
13d77ef9 | 346 | //25% clip in case highs and lows aren't clipped [marshmellow] |
2eec55c8 | 347 | int high, low; |
348 | if (getHiLo(BinStream, initLoopMax, &high, &low, 75, 75) < 1) | |
349 | return -1; //just noise | |
ba1a299c | 350 | |
2eec55c8 | 351 | // if clean clipped waves detected run alternate demod |
352 | if (DetectCleanAskWave(BinStream, *size, high, low)) | |
13d77ef9 | 353 | return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); |
13d77ef9 | 354 | |
6e984446 | 355 | int lastBit; //set first clock check - can go negative |
356 | size_t i, errCnt = 0, bitnum = 0; //output counter | |
2eec55c8 | 357 | uint8_t midBit = 0; |
2eec55c8 | 358 | size_t MaxBits = 1024; |
6e984446 | 359 | lastBit = start - *clk; |
ba1a299c | 360 | |
6e984446 | 361 | for (i = start; i < *size; ++i) { |
cc15a118 | 362 | if (i - lastBit == *clk){ |
2eec55c8 | 363 | if (BinStream[i] >= high) { |
364 | BinStream[bitnum++] = *invert; | |
365 | } else if (BinStream[i] <= low) { | |
366 | BinStream[bitnum++] = *invert ^ 1; | |
1e090a61 | 367 | } else { |
2eec55c8 | 368 | if (bitnum > 0) { |
2767fc02 | 369 | BinStream[bitnum++]=7; |
2eec55c8 | 370 | errCnt++; |
371 | } | |
372 | } | |
373 | midBit = 0; | |
374 | lastBit += *clk; | |
cc15a118 | 375 | } else if (i-lastBit == (*clk/2) && midBit == 0){ |
2eec55c8 | 376 | if (BinStream[i] >= high) { |
377 | BinStream[bitnum++] = *invert; | |
378 | } else if (BinStream[i] <= low) { | |
379 | BinStream[bitnum++] = *invert ^ 1; | |
380 | } else { | |
2eec55c8 | 381 | BinStream[bitnum] = BinStream[bitnum-1]; |
382 | bitnum++; | |
1e090a61 | 383 | } |
2eec55c8 | 384 | midBit = 1; |
ba1a299c | 385 | } |
2eec55c8 | 386 | if (bitnum >= MaxBits) break; |
1e090a61 | 387 | } |
2eec55c8 | 388 | *size = bitnum; |
389 | return errCnt; | |
eb191de6 | 390 | } |
11081e04 | 391 | |
392 | // demod gProxIIDemod | |
393 | // error returns as -x | |
394 | // success returns start position in BitStream | |
395 | // BitStream must contain previously askrawdemod and biphasedemoded data | |
396 | int gProxII_Demod(uint8_t BitStream[], size_t *size) | |
397 | { | |
398 | size_t startIdx=0; | |
399 | uint8_t preamble[] = {1,1,1,1,1,0}; | |
400 | ||
401 | uint8_t errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx); | |
402 | if (errChk == 0) return -3; //preamble not found | |
403 | if (*size != 96) return -2; //should have found 96 bits | |
404 | //check first 6 spacer bits to verify format | |
405 | if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){ | |
406 | //confirmed proper separator bits found | |
407 | //return start position | |
408 | return (int) startIdx; | |
409 | } | |
410 | return -5; | |
411 | } | |
412 | ||
ba1a299c | 413 | //translate wave to 11111100000 (1 for each short wave 0 for each long wave) |
f822a063 | 414 | size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) |
eb191de6 | 415 | { |
2eec55c8 | 416 | size_t last_transition = 0; |
417 | size_t idx = 1; | |
ac3ba7ee | 418 | //uint32_t maxVal=0; |
ba1a299c | 419 | if (fchigh==0) fchigh=10; |
420 | if (fclow==0) fclow=8; | |
84871873 | 421 | //set the threshold close to 0 (graph) or 128 std to avoid static |
422 | uint8_t threshold_value = 123; | |
ba1a299c | 423 | |
424 | // sync to first lo-hi transition, and threshold | |
425 | ||
426 | // Need to threshold first sample | |
427 | ||
428 | if(dest[0] < threshold_value) dest[0] = 0; | |
429 | else dest[0] = 1; | |
430 | ||
431 | size_t numBits = 0; | |
432 | // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8) | |
433 | // or 10 (fc/10) cycles but in practice due to noise etc we may end up with with anywhere | |
434 | // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10 | |
435 | for(idx = 1; idx < size; idx++) { | |
436 | // threshold current value | |
437 | ||
438 | if (dest[idx] < threshold_value) dest[idx] = 0; | |
439 | else dest[idx] = 1; | |
440 | ||
441 | // Check for 0->1 transition | |
442 | if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition | |
443 | if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise | |
444 | //do nothing with extra garbage | |
445 | } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves | |
2eec55c8 | 446 | dest[numBits++]=1; |
13d77ef9 | 447 | } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage |
448 | //do nothing with beginning garbage | |
449 | } else { //9+ = 10 waves | |
2eec55c8 | 450 | dest[numBits++]=0; |
ba1a299c | 451 | } |
452 | last_transition = idx; | |
ba1a299c | 453 | } |
454 | } | |
455 | return numBits; //Actually, it returns the number of bytes, but each byte represents a bit: 1 or 0 | |
eb191de6 | 456 | } |
457 | ||
ba1a299c | 458 | //translate 11111100000 to 10 |
2eec55c8 | 459 | size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, |
e0165dcf | 460 | uint8_t invert, uint8_t fchigh, uint8_t fclow) |
eb191de6 | 461 | { |
ba1a299c | 462 | uint8_t lastval=dest[0]; |
2eec55c8 | 463 | size_t idx=0; |
ba1a299c | 464 | size_t numBits=0; |
465 | uint32_t n=1; | |
ba1a299c | 466 | for( idx=1; idx < size; idx++) { |
13d77ef9 | 467 | n++; |
2eec55c8 | 468 | if (dest[idx]==lastval) continue; |
469 | ||
ba1a299c | 470 | //if lastval was 1, we have a 1->0 crossing |
13d77ef9 | 471 | if (dest[idx-1]==1) { |
75cbbe9a | 472 | if (!numBits && n < rfLen/fclow) { |
13d77ef9 | 473 | n=0; |
474 | lastval = dest[idx]; | |
475 | continue; | |
476 | } | |
75cbbe9a | 477 | n = (n * fclow + rfLen/2) / rfLen; |
13d77ef9 | 478 | } else {// 0->1 crossing |
479 | //test first bitsample too small | |
75cbbe9a | 480 | if (!numBits && n < rfLen/fchigh) { |
13d77ef9 | 481 | n=0; |
482 | lastval = dest[idx]; | |
483 | continue; | |
484 | } | |
75cbbe9a | 485 | n = (n * fchigh + rfLen/2) / rfLen; |
ba1a299c | 486 | } |
487 | if (n == 0) n = 1; | |
488 | ||
2eec55c8 | 489 | memset(dest+numBits, dest[idx-1]^invert , n); |
490 | numBits += n; | |
ba1a299c | 491 | n=0; |
492 | lastval=dest[idx]; | |
493 | }//end for | |
13d77ef9 | 494 | // if valid extra bits at the end were all the same frequency - add them in |
75cbbe9a | 495 | if (n > rfLen/fchigh) { |
13d77ef9 | 496 | if (dest[idx-2]==1) { |
75cbbe9a | 497 | n = (n * fclow + rfLen/2) / rfLen; |
13d77ef9 | 498 | } else { |
75cbbe9a | 499 | n = (n * fchigh + rfLen/2) / rfLen; |
13d77ef9 | 500 | } |
2eec55c8 | 501 | memset(dest+numBits, dest[idx-1]^invert , n); |
13d77ef9 | 502 | numBits += n; |
503 | } | |
ba1a299c | 504 | return numBits; |
eb191de6 | 505 | } |
506 | //by marshmellow (from holiman's base) | |
507 | // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod) | |
f822a063 | 508 | int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) |
eb191de6 | 509 | { |
ba1a299c | 510 | // FSK demodulator |
511 | size = fsk_wave_demod(dest, size, fchigh, fclow); | |
2eec55c8 | 512 | size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow); |
ba1a299c | 513 | return size; |
eb191de6 | 514 | } |
a1d17964 | 515 | |
eb191de6 | 516 | // loop to get raw HID waveform then FSK demodulate the TAG ID from it |
ec75f5c1 | 517 | int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) |
eb191de6 | 518 | { |
e0165dcf | 519 | if (justNoise(dest, *size)) return -1; |
520 | ||
521 | size_t numStart=0, size2=*size, startIdx=0; | |
522 | // FSK demodulator | |
523 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a | |
2eec55c8 | 524 | if (*size < 96*2) return -2; |
e0165dcf | 525 | // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 |
526 | uint8_t preamble[] = {0,0,0,1,1,1,0,1}; | |
527 | // find bitstring in array | |
528 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
529 | if (errChk == 0) return -3; //preamble not found | |
530 | ||
531 | numStart = startIdx + sizeof(preamble); | |
532 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
533 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
534 | if (dest[idx] == dest[idx+1]){ | |
535 | return -4; //not manchester data | |
536 | } | |
537 | *hi2 = (*hi2<<1)|(*hi>>31); | |
538 | *hi = (*hi<<1)|(*lo>>31); | |
539 | //Then, shift in a 0 or one into low | |
540 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
541 | *lo=(*lo<<1)|1; | |
542 | else // 0 1 | |
543 | *lo=(*lo<<1)|0; | |
544 | } | |
545 | return (int)startIdx; | |
eb191de6 | 546 | } |
547 | ||
ec75f5c1 | 548 | // loop to get raw paradox waveform then FSK demodulate the TAG ID from it |
a1d17964 | 549 | int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) |
ec75f5c1 | 550 | { |
a1d17964 | 551 | if (justNoise(dest, *size)) return -1; |
552 | ||
553 | size_t numStart=0, size2=*size, startIdx=0; | |
ec75f5c1 | 554 | // FSK demodulator |
a1d17964 | 555 | *size = fskdemod(dest, size2,50,1,10,8); //fsk2a |
556 | if (*size < 96) return -2; | |
ec75f5c1 | 557 | |
a1d17964 | 558 | // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 |
559 | uint8_t preamble[] = {0,0,0,0,1,1,1,1}; | |
560 | ||
561 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
562 | if (errChk == 0) return -3; //preamble not found | |
563 | ||
564 | numStart = startIdx + sizeof(preamble); | |
565 | // final loop, go over previously decoded FSK data and manchester decode into usable tag ID | |
566 | for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ | |
567 | if (dest[idx] == dest[idx+1]) | |
568 | return -4; //not manchester data | |
569 | *hi2 = (*hi2<<1)|(*hi>>31); | |
570 | *hi = (*hi<<1)|(*lo>>31); | |
571 | //Then, shift in a 0 or one into low | |
572 | if (dest[idx] && !dest[idx+1]) // 1 0 | |
573 | *lo=(*lo<<1)|1; | |
574 | else // 0 1 | |
575 | *lo=(*lo<<1)|0; | |
ec75f5c1 | 576 | } |
a1d17964 | 577 | return (int)startIdx; |
ec75f5c1 | 578 | } |
579 | ||
ba1a299c | 580 | uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) |
eb191de6 | 581 | { |
ba1a299c | 582 | uint32_t num = 0; |
583 | for(int i = 0 ; i < numbits ; i++) | |
584 | { | |
585 | num = (num << 1) | (*src); | |
586 | src++; | |
587 | } | |
588 | return num; | |
eb191de6 | 589 | } |
590 | ||
591 | int IOdemodFSK(uint8_t *dest, size_t size) | |
592 | { | |
a1d17964 | 593 | if (justNoise(dest, size)) return -1; |
ba1a299c | 594 | //make sure buffer has data |
a1d17964 | 595 | if (size < 66*64) return -2; |
ba1a299c | 596 | // FSK demodulator |
a1d17964 | 597 | size = fskdemod(dest, size, 64, 1, 10, 8); // FSK2a RF/64 |
598 | if (size < 65) return -3; //did we get a good demod? | |
ba1a299c | 599 | //Index map |
600 | //0 10 20 30 40 50 60 | |
601 | //| | | | | | | | |
602 | //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23 | |
603 | //----------------------------------------------------------------------------- | |
604 | //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11 | |
605 | // | |
606 | //XSF(version)facility:codeone+codetwo | |
607 | //Handle the data | |
a1d17964 | 608 | size_t startIdx = 0; |
609 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1}; | |
610 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx); | |
611 | if (errChk == 0) return -4; //preamble not found | |
eb191de6 | 612 | |
a1d17964 | 613 | if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){ |
614 | //confirmed proper separator bits found | |
615 | //return start position | |
616 | return (int) startIdx; | |
1e090a61 | 617 | } |
a1d17964 | 618 | return -5; |
1e090a61 | 619 | } |
620 | ||
621 | // by marshmellow | |
622 | // takes a array of binary values, start position, length of bits per parity (includes parity bit), | |
623 | // Parity Type (1 for odd 0 for even), and binary Length (length to run) | |
624 | size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) | |
625 | { | |
626 | uint32_t parityWd = 0; | |
627 | size_t j = 0, bitCnt = 0; | |
628 | for (int word = 0; word < (bLen); word+=pLen){ | |
629 | for (int bit=0; bit < pLen; bit++){ | |
630 | parityWd = (parityWd << 1) | BitStream[startIdx+word+bit]; | |
f3bf15e4 | 631 | BitStream[j++] = (BitStream[startIdx+word+bit]); |
1e090a61 | 632 | } |
633 | j--; | |
634 | // if parity fails then return 0 | |
635 | if (parityTest(parityWd, pLen, pType) == 0) return -1; | |
636 | bitCnt+=(pLen-1); | |
637 | parityWd = 0; | |
638 | } | |
639 | // if we got here then all the parities passed | |
640 | //return ID start index and size | |
641 | return bitCnt; | |
642 | } | |
643 | ||
644 | // by marshmellow | |
645 | // FSK Demod then try to locate an AWID ID | |
a1d17964 | 646 | int AWIDdemodFSK(uint8_t *dest, size_t *size) |
1e090a61 | 647 | { |
a1d17964 | 648 | //make sure buffer has enough data |
649 | if (*size < 96*50) return -1; | |
650 | ||
651 | if (justNoise(dest, *size)) return -2; | |
1e090a61 | 652 | |
653 | // FSK demodulator | |
a1d17964 | 654 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 |
655 | if (*size < 96) return -3; //did we get a good demod? | |
656 | ||
657 | uint8_t preamble[] = {0,0,0,0,0,0,0,1}; | |
658 | size_t startIdx = 0; | |
659 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
660 | if (errChk == 0) return -4; //preamble not found | |
661 | if (*size != 96) return -5; | |
662 | return (int)startIdx; | |
1e090a61 | 663 | } |
664 | ||
665 | // by marshmellow | |
666 | // FSK Demod then try to locate an Farpointe Data (pyramid) ID | |
a1d17964 | 667 | int PyramiddemodFSK(uint8_t *dest, size_t *size) |
1e090a61 | 668 | { |
f3bf15e4 | 669 | //make sure buffer has data |
670 | if (*size < 128*50) return -5; | |
a1d17964 | 671 | |
f3bf15e4 | 672 | //test samples are not just noise |
673 | if (justNoise(dest, *size)) return -1; | |
1e090a61 | 674 | |
f3bf15e4 | 675 | // FSK demodulator |
676 | *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 | |
677 | if (*size < 128) return -2; //did we get a good demod? | |
a1d17964 | 678 | |
f3bf15e4 | 679 | uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; |
a1d17964 | 680 | size_t startIdx = 0; |
681 | uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); | |
682 | if (errChk == 0) return -4; //preamble not found | |
683 | if (*size != 128) return -3; | |
684 | return (int)startIdx; | |
1e090a61 | 685 | } |
686 | ||
6de43508 | 687 | |
cc15a118 | 688 | uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, uint8_t high, uint8_t low) |
6de43508 | 689 | { |
1fbf8956 | 690 | uint16_t allPeaks=1; |
6de43508 | 691 | uint16_t cntPeaks=0; |
cc15a118 | 692 | size_t loopEnd = 512+60; |
1fbf8956 | 693 | if (loopEnd > size) loopEnd = size; |
694 | for (size_t i=60; i<loopEnd; i++){ | |
6de43508 | 695 | if (dest[i]>low && dest[i]<high) |
696 | allPeaks=0; | |
697 | else | |
698 | cntPeaks++; | |
699 | } | |
1fbf8956 | 700 | if (allPeaks == 0){ |
701 | if (cntPeaks > 300) return 1; | |
6de43508 | 702 | } |
703 | return allPeaks; | |
704 | } | |
705 | ||
2eec55c8 | 706 | // by marshmellow |
707 | // to help detect clocks on heavily clipped samples | |
cc15a118 | 708 | // based on count of low to low |
709 | int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low) | |
13d77ef9 | 710 | { |
cc15a118 | 711 | uint8_t fndClk[] = {8,16,32,40,50,64,128}; |
712 | size_t startwave; | |
713 | size_t i = 0; | |
714 | size_t minClk = 255; | |
715 | // get to first full low to prime loop and skip incomplete first pulse | |
716 | while ((dest[i] < high) && (i < size)) | |
717 | ++i; | |
718 | while ((dest[i] > low) && (i < size)) | |
719 | ++i; | |
720 | ||
721 | // loop through all samples | |
722 | while (i < size) { | |
723 | // measure from low to low | |
724 | while ((dest[i] > low) && (i < size)) | |
725 | ++i; | |
726 | startwave= i; | |
727 | while ((dest[i] < high) && (i < size)) | |
728 | ++i; | |
729 | while ((dest[i] > low) && (i < size)) | |
730 | ++i; | |
731 | //get minimum measured distance | |
732 | if (i-startwave < minClk && i < size) | |
733 | minClk = i - startwave; | |
13d77ef9 | 734 | } |
cc15a118 | 735 | // set clock |
736 | for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) { | |
737 | if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) | |
738 | return fndClk[clkCnt]; | |
13d77ef9 | 739 | } |
cc15a118 | 740 | return 0; |
13d77ef9 | 741 | } |
742 | ||
eb191de6 | 743 | // by marshmellow |
744 | // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping) | |
745 | // maybe somehow adjust peak trimming value based on samples to fix? | |
6de43508 | 746 | // return start index of best starting position for that clock and return clock (by reference) |
747 | int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) | |
eb191de6 | 748 | { |
6e984446 | 749 | size_t i=1; |
cc15a118 | 750 | uint8_t clk[] = {255,8,16,32,40,50,64,100,128,255}; |
751 | uint8_t clkEnd = 9; | |
2eec55c8 | 752 | uint8_t loopCnt = 255; //don't need to loop through entire array... |
cc15a118 | 753 | if (size <= loopCnt) return -1; //not enough samples |
6e984446 | 754 | |
755 | //if we already have a valid clock | |
756 | uint8_t clockFnd=0; | |
cc15a118 | 757 | for (;i<clkEnd;++i) |
758 | if (clk[i] == *clock) clockFnd = i; | |
6e984446 | 759 | //clock found but continue to find best startpos |
e0165dcf | 760 | |
761 | //get high and low peak | |
762 | int peak, low; | |
2eec55c8 | 763 | if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return -1; |
e0165dcf | 764 | |
765 | //test for large clean peaks | |
cc15a118 | 766 | if (!clockFnd){ |
767 | if (DetectCleanAskWave(dest, size, peak, low)==1){ | |
768 | int ans = DetectStrongAskClock(dest, size, peak, low); | |
769 | for (i=clkEnd-1; i>0; i--){ | |
770 | if (clk[i] == ans) { | |
771 | *clock = ans; | |
772 | //clockFnd = i; | |
773 | return 0; // for strong waves i don't use the 'best start position' yet... | |
774 | //break; //clock found but continue to find best startpos [not yet] | |
775 | } | |
e0165dcf | 776 | } |
777 | } | |
778 | } | |
cc15a118 | 779 | |
2eec55c8 | 780 | uint8_t ii; |
781 | uint8_t clkCnt, tol = 0; | |
782 | uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; | |
783 | uint8_t bestStart[]={0,0,0,0,0,0,0,0,0}; | |
784 | size_t errCnt = 0; | |
785 | size_t arrLoc, loopEnd; | |
6e984446 | 786 | |
cc15a118 | 787 | if (clockFnd>0) { |
788 | clkCnt = clockFnd; | |
789 | clkEnd = clockFnd+1; | |
790 | } | |
791 | else clkCnt=1; | |
792 | ||
793 | //test each valid clock from smallest to greatest to see which lines up | |
794 | for(; clkCnt < clkEnd; clkCnt++){ | |
e0165dcf | 795 | if (clk[clkCnt] == 32){ |
796 | tol=1; | |
797 | }else{ | |
798 | tol=0; | |
799 | } | |
2767fc02 | 800 | //if no errors allowed - keep start within the first clock |
cc15a118 | 801 | if (!maxErr && size > clk[clkCnt]*2 + tol && clk[clkCnt]<128) loopCnt=clk[clkCnt]*2; |
e0165dcf | 802 | bestErr[clkCnt]=1000; |
6e984446 | 803 | //try lining up the peaks by moving starting point (try first few clocks) |
cc15a118 | 804 | for (ii=0; ii < loopCnt; ii++){ |
2eec55c8 | 805 | if (dest[ii] < peak && dest[ii] > low) continue; |
806 | ||
807 | errCnt=0; | |
808 | // now that we have the first one lined up test rest of wave array | |
809 | loopEnd = ((size-ii-tol) / clk[clkCnt]) - 1; | |
810 | for (i=0; i < loopEnd; ++i){ | |
811 | arrLoc = ii + (i * clk[clkCnt]); | |
812 | if (dest[arrLoc] >= peak || dest[arrLoc] <= low){ | |
813 | }else if (dest[arrLoc-tol] >= peak || dest[arrLoc-tol] <= low){ | |
814 | }else if (dest[arrLoc+tol] >= peak || dest[arrLoc+tol] <= low){ | |
815 | }else{ //error no peak detected | |
816 | errCnt++; | |
e0165dcf | 817 | } |
818 | } | |
cc15a118 | 819 | //if we found no errors then we can stop here and a low clock (common clocks) |
2eec55c8 | 820 | // this is correct one - return this clock |
821 | //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i); | |
cc15a118 | 822 | if(errCnt==0 && clkCnt<7) { |
823 | if (!clockFnd) *clock = clk[clkCnt]; | |
2eec55c8 | 824 | return ii; |
825 | } | |
826 | //if we found errors see if it is lowest so far and save it as best run | |
827 | if(errCnt<bestErr[clkCnt]){ | |
828 | bestErr[clkCnt]=errCnt; | |
829 | bestStart[clkCnt]=ii; | |
830 | } | |
e0165dcf | 831 | } |
832 | } | |
cc15a118 | 833 | uint8_t iii; |
e0165dcf | 834 | uint8_t best=0; |
cc15a118 | 835 | for (iii=1; iii<clkEnd; ++iii){ |
2eec55c8 | 836 | if (bestErr[iii] < bestErr[best]){ |
837 | if (bestErr[iii] == 0) bestErr[iii]=1; | |
e0165dcf | 838 | // current best bit to error ratio vs new bit to error ratio |
2eec55c8 | 839 | if ( (size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii] ){ |
e0165dcf | 840 | best = iii; |
841 | } | |
842 | } | |
843 | } | |
2767fc02 | 844 | //if (bestErr[best] > maxErr) return -1; |
cc15a118 | 845 | if (!clockFnd) *clock = clk[best]; |
e0165dcf | 846 | return bestStart[best]; |
eb191de6 | 847 | } |
ba1a299c | 848 | |
849 | //by marshmellow | |
6de43508 | 850 | //detect psk clock by reading each phase shift |
851 | // a phase shift is determined by measuring the sample length of each wave | |
852 | int DetectPSKClock(uint8_t dest[], size_t size, int clock) | |
ba1a299c | 853 | { |
e0165dcf | 854 | uint8_t clk[]={255,16,32,40,50,64,100,128,255}; //255 is not a valid clock |
855 | uint16_t loopCnt = 4096; //don't need to loop through entire array... | |
856 | if (size == 0) return 0; | |
857 | if (size<loopCnt) loopCnt = size; | |
858 | ||
859 | //if we already have a valid clock quit | |
860 | size_t i=1; | |
861 | for (; i < 8; ++i) | |
862 | if (clk[i] == clock) return clock; | |
863 | ||
864 | size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0; | |
865 | uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1; | |
866 | uint16_t peakcnt=0, errCnt=0, waveLenCnt=0; | |
867 | uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000}; | |
868 | uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0}; | |
2eec55c8 | 869 | fc = countFC(dest, size, 0); |
870 | if (fc!=2 && fc!=4 && fc!=8) return -1; | |
e0165dcf | 871 | //PrintAndLog("DEBUG: FC: %d",fc); |
872 | ||
873 | //find first full wave | |
874 | for (i=0; i<loopCnt; i++){ | |
875 | if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
876 | if (waveStart == 0) { | |
877 | waveStart = i+1; | |
878 | //PrintAndLog("DEBUG: waveStart: %d",waveStart); | |
879 | } else { | |
880 | waveEnd = i+1; | |
881 | //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); | |
882 | waveLenCnt = waveEnd-waveStart; | |
883 | if (waveLenCnt > fc){ | |
884 | firstFullWave = waveStart; | |
885 | fullWaveLen=waveLenCnt; | |
886 | break; | |
887 | } | |
888 | waveStart=0; | |
889 | } | |
890 | } | |
891 | } | |
892 | //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); | |
893 | ||
894 | //test each valid clock from greatest to smallest to see which lines up | |
895 | for(clkCnt=7; clkCnt >= 1 ; clkCnt--){ | |
896 | lastClkBit = firstFullWave; //set end of wave as clock align | |
897 | waveStart = 0; | |
898 | errCnt=0; | |
899 | peakcnt=0; | |
900 | //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d",clk[clkCnt],lastClkBit); | |
901 | ||
902 | for (i = firstFullWave+fullWaveLen-1; i < loopCnt-2; i++){ | |
903 | //top edge of wave = start of new wave | |
904 | if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
905 | if (waveStart == 0) { | |
906 | waveStart = i+1; | |
907 | waveLenCnt=0; | |
908 | } else { //waveEnd | |
909 | waveEnd = i+1; | |
910 | waveLenCnt = waveEnd-waveStart; | |
911 | if (waveLenCnt > fc){ | |
912 | //if this wave is a phase shift | |
913 | //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, ii: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+clk[clkCnt]-tol,ii+1,fc); | |
914 | if (i+1 >= lastClkBit + clk[clkCnt] - tol){ //should be a clock bit | |
915 | peakcnt++; | |
916 | lastClkBit+=clk[clkCnt]; | |
917 | } else if (i<lastClkBit+8){ | |
918 | //noise after a phase shift - ignore | |
919 | } else { //phase shift before supposed to based on clock | |
920 | errCnt++; | |
921 | } | |
922 | } else if (i+1 > lastClkBit + clk[clkCnt] + tol + fc){ | |
923 | lastClkBit+=clk[clkCnt]; //no phase shift but clock bit | |
924 | } | |
925 | waveStart=i+1; | |
926 | } | |
927 | } | |
928 | } | |
929 | if (errCnt == 0){ | |
930 | return clk[clkCnt]; | |
931 | } | |
932 | if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt; | |
933 | if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt; | |
934 | } | |
935 | //all tested with errors | |
936 | //return the highest clk with the most peaks found | |
937 | uint8_t best=7; | |
938 | for (i=7; i>=1; i--){ | |
939 | if (peaksdet[i] > peaksdet[best]) { | |
940 | best = i; | |
941 | } | |
942 | //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]); | |
943 | } | |
944 | return clk[best]; | |
ba1a299c | 945 | } |
946 | ||
6de43508 | 947 | //by marshmellow |
948 | //detect nrz clock by reading #peaks vs no peaks(or errors) | |
949 | int DetectNRZClock(uint8_t dest[], size_t size, int clock) | |
ba1a299c | 950 | { |
2eec55c8 | 951 | size_t i=0; |
952 | uint8_t clk[]={8,16,32,40,50,64,100,128,255}; | |
953 | size_t loopCnt = 4096; //don't need to loop through entire array... | |
e0165dcf | 954 | if (size == 0) return 0; |
955 | if (size<loopCnt) loopCnt = size; | |
956 | ||
957 | //if we already have a valid clock quit | |
958 | for (; i < 8; ++i) | |
959 | if (clk[i] == clock) return clock; | |
960 | ||
961 | //get high and low peak | |
962 | int peak, low; | |
2eec55c8 | 963 | if (getHiLo(dest, loopCnt, &peak, &low, 75, 75) < 1) return 0; |
e0165dcf | 964 | |
965 | //PrintAndLog("DEBUG: peak: %d, low: %d",peak,low); | |
2eec55c8 | 966 | size_t ii; |
e0165dcf | 967 | uint8_t clkCnt; |
968 | uint8_t tol = 0; | |
2eec55c8 | 969 | uint16_t peakcnt=0; |
970 | uint16_t peaksdet[]={0,0,0,0,0,0,0,0}; | |
971 | uint16_t maxPeak=0; | |
e0165dcf | 972 | //test for large clipped waves |
973 | for (i=0; i<loopCnt; i++){ | |
974 | if (dest[i] >= peak || dest[i] <= low){ | |
975 | peakcnt++; | |
976 | } else { | |
977 | if (peakcnt>0 && maxPeak < peakcnt){ | |
978 | maxPeak = peakcnt; | |
979 | } | |
980 | peakcnt=0; | |
981 | } | |
982 | } | |
983 | peakcnt=0; | |
984 | //test each valid clock from smallest to greatest to see which lines up | |
985 | for(clkCnt=0; clkCnt < 8; ++clkCnt){ | |
986 | //ignore clocks smaller than largest peak | |
987 | if (clk[clkCnt]<maxPeak) continue; | |
988 | ||
989 | //try lining up the peaks by moving starting point (try first 256) | |
990 | for (ii=0; ii< loopCnt; ++ii){ | |
991 | if ((dest[ii] >= peak) || (dest[ii] <= low)){ | |
992 | peakcnt=0; | |
993 | // now that we have the first one lined up test rest of wave array | |
994 | for (i=0; i < ((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ | |
995 | if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ | |
996 | peakcnt++; | |
997 | } | |
998 | } | |
999 | if(peakcnt>peaksdet[clkCnt]) { | |
1000 | peaksdet[clkCnt]=peakcnt; | |
1001 | } | |
1002 | } | |
1003 | } | |
1004 | } | |
1005 | int iii=7; | |
2eec55c8 | 1006 | uint8_t best=0; |
e0165dcf | 1007 | for (iii=7; iii > 0; iii--){ |
1008 | if (peaksdet[iii] > peaksdet[best]){ | |
1009 | best = iii; | |
1010 | } | |
1011 | //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best]); | |
1012 | } | |
1013 | return clk[best]; | |
ba1a299c | 1014 | } |
1015 | ||
04d2721b | 1016 | // by marshmellow |
1017 | // convert psk1 demod to psk2 demod | |
1018 | // only transition waves are 1s | |
1019 | void psk1TOpsk2(uint8_t *BitStream, size_t size) | |
1020 | { | |
1021 | size_t i=1; | |
1022 | uint8_t lastBit=BitStream[0]; | |
1023 | for (; i<size; i++){ | |
2767fc02 | 1024 | if (BitStream[i]==7){ |
7a8a982b | 1025 | //ignore errors |
1026 | } else if (lastBit!=BitStream[i]){ | |
04d2721b | 1027 | lastBit=BitStream[i]; |
1028 | BitStream[i]=1; | |
1029 | } else { | |
1030 | BitStream[i]=0; | |
1031 | } | |
1032 | } | |
1033 | return; | |
1034 | } | |
ba1a299c | 1035 | |
3bc66a96 | 1036 | // by marshmellow |
1037 | // convert psk2 demod to psk1 demod | |
1038 | // from only transition waves are 1s to phase shifts change bit | |
1039 | void psk2TOpsk1(uint8_t *BitStream, size_t size) | |
1040 | { | |
712ebfa6 | 1041 | uint8_t phase=0; |
1042 | for (size_t i=0; i<size; i++){ | |
1043 | if (BitStream[i]==1){ | |
3bc66a96 | 1044 | phase ^=1; |
1045 | } | |
1046 | BitStream[i]=phase; | |
1047 | } | |
1048 | return; | |
1049 | } | |
1050 | ||
04d2721b | 1051 | // redesigned by marshmellow adjusted from existing decode functions |
1052 | // indala id decoding - only tested on 26 bit tags, but attempted to make it work for more | |
ba1a299c | 1053 | int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert) |
1054 | { | |
1055 | //26 bit 40134 format (don't know other formats) | |
1056 | int i; | |
84871873 | 1057 | int long_wait=29;//29 leading zeros in format |
ba1a299c | 1058 | int start; |
1059 | int first = 0; | |
1060 | int first2 = 0; | |
1061 | int bitCnt = 0; | |
1062 | int ii; | |
1063 | // Finding the start of a UID | |
1064 | for (start = 0; start <= *size - 250; start++) { | |
1065 | first = bitStream[start]; | |
1066 | for (i = start; i < start + long_wait; i++) { | |
1067 | if (bitStream[i] != first) { | |
1068 | break; | |
1069 | } | |
1070 | } | |
1071 | if (i == (start + long_wait)) { | |
1072 | break; | |
1073 | } | |
1074 | } | |
1075 | if (start == *size - 250 + 1) { | |
1076 | // did not find start sequence | |
1077 | return -1; | |
1078 | } | |
ba1a299c | 1079 | // Inverting signal if needed |
1080 | if (first == 1) { | |
1081 | for (i = start; i < *size; i++) { | |
1082 | bitStream[i] = !bitStream[i]; | |
1083 | } | |
1084 | *invert = 1; | |
1085 | }else *invert=0; | |
1086 | ||
1087 | int iii; | |
84871873 | 1088 | //found start once now test length by finding next one |
ba1a299c | 1089 | for (ii=start+29; ii <= *size - 250; ii++) { |
1090 | first2 = bitStream[ii]; | |
1091 | for (iii = ii; iii < ii + long_wait; iii++) { | |
1092 | if (bitStream[iii] != first2) { | |
1093 | break; | |
1094 | } | |
1095 | } | |
1096 | if (iii == (ii + long_wait)) { | |
1097 | break; | |
1098 | } | |
1099 | } | |
1100 | if (ii== *size - 250 + 1){ | |
1101 | // did not find second start sequence | |
1102 | return -2; | |
1103 | } | |
1104 | bitCnt=ii-start; | |
1105 | ||
1106 | // Dumping UID | |
1107 | i = start; | |
1108 | for (ii = 0; ii < bitCnt; ii++) { | |
1109 | bitStream[ii] = bitStream[i++]; | |
1110 | } | |
1111 | *size=bitCnt; | |
1112 | return 1; | |
1113 | } | |
1114 | ||
6de43508 | 1115 | // by marshmellow - demodulate NRZ wave (both similar enough) |
04d2721b | 1116 | // peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak |
6de43508 | 1117 | // there probably is a much simpler way to do this.... |
1118 | int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) | |
ba1a299c | 1119 | { |
e0165dcf | 1120 | if (justNoise(dest, *size)) return -1; |
1121 | *clk = DetectNRZClock(dest, *size, *clk); | |
1122 | if (*clk==0) return -2; | |
2eec55c8 | 1123 | size_t i, gLen = 4096; |
e0165dcf | 1124 | if (gLen>*size) gLen = *size; |
1125 | int high, low; | |
1126 | if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low | |
1127 | int lastBit = 0; //set first clock check | |
2eec55c8 | 1128 | size_t iii = 0, bitnum = 0; //bitnum counter |
1129 | uint16_t errCnt = 0, MaxBits = 1000; | |
1130 | size_t bestErrCnt = maxErr+1; | |
1131 | size_t bestPeakCnt = 0, bestPeakStart = 0; | |
1132 | uint8_t bestFirstPeakHigh=0, firstPeakHigh=0, curBit=0, bitHigh=0, errBitHigh=0; | |
e0165dcf | 1133 | 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 |
e0165dcf | 1134 | uint16_t peakCnt=0; |
1135 | uint8_t ignoreWindow=4; | |
2eec55c8 | 1136 | uint8_t ignoreCnt=ignoreWindow; //in case of noise near peak |
e0165dcf | 1137 | //loop to find first wave that works - align to clock |
1138 | for (iii=0; iii < gLen; ++iii){ | |
1139 | if ((dest[iii]>=high) || (dest[iii]<=low)){ | |
1140 | if (dest[iii]>=high) firstPeakHigh=1; | |
1141 | else firstPeakHigh=0; | |
1142 | lastBit=iii-*clk; | |
1143 | peakCnt=0; | |
1144 | errCnt=0; | |
e0165dcf | 1145 | //loop through to see if this start location works |
1146 | for (i = iii; i < *size; ++i) { | |
2eec55c8 | 1147 | // if we are at a clock bit |
1148 | if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) { | |
1149 | //test high/low | |
1150 | if (dest[i] >= high || dest[i] <= low) { | |
1151 | bitHigh = 1; | |
1152 | peakCnt++; | |
1153 | errBitHigh = 0; | |
1154 | ignoreCnt = ignoreWindow; | |
1155 | lastBit += *clk; | |
1156 | } else if (i == lastBit + *clk + tol) { | |
1157 | lastBit += *clk; | |
1158 | } | |
e0165dcf | 1159 | //else if no bars found |
2eec55c8 | 1160 | } else if (dest[i] < high && dest[i] > low){ |
e0165dcf | 1161 | if (ignoreCnt==0){ |
1162 | bitHigh=0; | |
2eec55c8 | 1163 | if (errBitHigh==1) errCnt++; |
e0165dcf | 1164 | errBitHigh=0; |
1165 | } else { | |
1166 | ignoreCnt--; | |
1167 | } | |
2eec55c8 | 1168 | } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) { |
e0165dcf | 1169 | //error bar found no clock... |
1170 | errBitHigh=1; | |
1171 | } | |
2eec55c8 | 1172 | if (((i-iii) / *clk)>=MaxBits) break; |
e0165dcf | 1173 | } |
1174 | //we got more than 64 good bits and not all errors | |
2eec55c8 | 1175 | if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) { |
e0165dcf | 1176 | //possible good read |
2eec55c8 | 1177 | if (!errCnt || peakCnt > bestPeakCnt){ |
e0165dcf | 1178 | bestFirstPeakHigh=firstPeakHigh; |
1179 | bestErrCnt = errCnt; | |
1180 | bestPeakCnt = peakCnt; | |
1181 | bestPeakStart = iii; | |
2eec55c8 | 1182 | if (!errCnt) break; //great read - finish |
e0165dcf | 1183 | } |
e0165dcf | 1184 | } |
1185 | } | |
1186 | } | |
1187 | //PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart); | |
2eec55c8 | 1188 | if (bestErrCnt > maxErr) return bestErrCnt; |
1189 | ||
1190 | //best run is good enough set to best run and set overwrite BinStream | |
1191 | lastBit = bestPeakStart - *clk; | |
1192 | memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk); | |
1193 | bitnum += (bestPeakStart / *clk); | |
1194 | for (i = bestPeakStart; i < *size; ++i) { | |
1195 | // if expecting a clock bit | |
1196 | if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) { | |
1197 | // test high/low | |
1198 | if (dest[i] >= high || dest[i] <= low) { | |
1199 | peakCnt++; | |
1200 | bitHigh = 1; | |
1201 | errBitHigh = 0; | |
1202 | ignoreCnt = ignoreWindow; | |
1203 | curBit = *invert; | |
1204 | if (dest[i] >= high) curBit ^= 1; | |
1205 | dest[bitnum++] = curBit; | |
1206 | lastBit += *clk; | |
1207 | //else no bars found in clock area | |
1208 | } else if (i == lastBit + *clk + tol) { | |
1209 | dest[bitnum++] = curBit; | |
1210 | lastBit += *clk; | |
1211 | } | |
1212 | //else if no bars found | |
1213 | } else if (dest[i] < high && dest[i] > low){ | |
1214 | if (ignoreCnt == 0){ | |
1215 | bitHigh = 0; | |
1216 | if (errBitHigh == 1){ | |
2767fc02 | 1217 | dest[bitnum++] = 7; |
2eec55c8 | 1218 | errCnt++; |
e0165dcf | 1219 | } |
2eec55c8 | 1220 | errBitHigh=0; |
1221 | } else { | |
1222 | ignoreCnt--; | |
e0165dcf | 1223 | } |
2eec55c8 | 1224 | } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) { |
1225 | //error bar found no clock... | |
1226 | errBitHigh=1; | |
e0165dcf | 1227 | } |
2eec55c8 | 1228 | if (bitnum >= MaxBits) break; |
e0165dcf | 1229 | } |
2eec55c8 | 1230 | *size = bitnum; |
1231 | return bestErrCnt; | |
ba1a299c | 1232 | } |
1233 | ||
1e090a61 | 1234 | //by marshmellow |
03e6bb4a | 1235 | //detects the bit clock for FSK given the high and low Field Clocks |
1236 | uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) | |
1e090a61 | 1237 | { |
e0165dcf | 1238 | uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; |
1239 | uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1240 | uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; | |
1241 | uint8_t rfLensFnd = 0; | |
2eec55c8 | 1242 | uint8_t lastFCcnt = 0; |
1243 | uint16_t fcCounter = 0; | |
e0165dcf | 1244 | uint16_t rfCounter = 0; |
1245 | uint8_t firstBitFnd = 0; | |
1246 | size_t i; | |
1247 | if (size == 0) return 0; | |
1248 | ||
1249 | uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); | |
1250 | rfLensFnd=0; | |
1251 | fcCounter=0; | |
1252 | rfCounter=0; | |
1253 | firstBitFnd=0; | |
1254 | //PrintAndLog("DEBUG: fcTol: %d",fcTol); | |
1255 | // prime i to first up transition | |
1256 | for (i = 1; i < size-1; i++) | |
1257 | if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) | |
1258 | break; | |
1259 | ||
1260 | for (; i < size-1; i++){ | |
2eec55c8 | 1261 | fcCounter++; |
1262 | rfCounter++; | |
1263 | ||
1264 | if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1]) | |
1265 | continue; | |
1266 | // else new peak | |
1267 | // if we got less than the small fc + tolerance then set it to the small fc | |
1268 | if (fcCounter < fcLow+fcTol) | |
1269 | fcCounter = fcLow; | |
1270 | else //set it to the large fc | |
1271 | fcCounter = fcHigh; | |
1272 | ||
1273 | //look for bit clock (rf/xx) | |
1274 | if ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){ | |
1275 | //not the same size as the last wave - start of new bit sequence | |
1276 | if (firstBitFnd > 1){ //skip first wave change - probably not a complete bit | |
1277 | for (int ii=0; ii<15; ii++){ | |
1278 | if (rfLens[ii] == rfCounter){ | |
1279 | rfCnts[ii]++; | |
1280 | rfCounter = 0; | |
1281 | break; | |
e0165dcf | 1282 | } |
e0165dcf | 1283 | } |
2eec55c8 | 1284 | if (rfCounter > 0 && rfLensFnd < 15){ |
1285 | //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); | |
1286 | rfCnts[rfLensFnd]++; | |
1287 | rfLens[rfLensFnd++] = rfCounter; | |
1288 | } | |
1289 | } else { | |
1290 | firstBitFnd++; | |
e0165dcf | 1291 | } |
2eec55c8 | 1292 | rfCounter=0; |
1293 | lastFCcnt=fcCounter; | |
e0165dcf | 1294 | } |
2eec55c8 | 1295 | fcCounter=0; |
e0165dcf | 1296 | } |
1297 | uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; | |
1298 | ||
1299 | for (i=0; i<15; i++){ | |
1300 | //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); | |
1301 | //get highest 2 RF values (might need to get more values to compare or compare all?) | |
1302 | if (rfCnts[i]>rfCnts[rfHighest]){ | |
1303 | rfHighest3=rfHighest2; | |
1304 | rfHighest2=rfHighest; | |
1305 | rfHighest=i; | |
1306 | } else if(rfCnts[i]>rfCnts[rfHighest2]){ | |
1307 | rfHighest3=rfHighest2; | |
1308 | rfHighest2=i; | |
1309 | } else if(rfCnts[i]>rfCnts[rfHighest3]){ | |
1310 | rfHighest3=i; | |
1311 | } | |
1312 | } | |
1313 | // set allowed clock remainder tolerance to be 1 large field clock length+1 | |
1314 | // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off | |
1315 | uint8_t tol1 = fcHigh+1; | |
1316 | ||
1317 | //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); | |
1318 | ||
1319 | // loop to find the highest clock that has a remainder less than the tolerance | |
1320 | // compare samples counted divided by | |
1321 | int ii=7; | |
1322 | for (; ii>=0; ii--){ | |
1323 | if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ | |
1324 | if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ | |
1325 | if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ | |
1326 | break; | |
1327 | } | |
1328 | } | |
1329 | } | |
1330 | } | |
1331 | ||
1332 | if (ii<0) return 0; // oops we went too far | |
1333 | ||
1334 | return clk[ii]; | |
03e6bb4a | 1335 | } |
1e090a61 | 1336 | |
03e6bb4a | 1337 | //by marshmellow |
1338 | //countFC is to detect the field clock lengths. | |
1339 | //counts and returns the 2 most common wave lengths | |
6de43508 | 1340 | //mainly used for FSK field clock detection |
2eec55c8 | 1341 | uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj) |
03e6bb4a | 1342 | { |
e0165dcf | 1343 | uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; |
1344 | uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; | |
1345 | uint8_t fcLensFnd = 0; | |
1346 | uint8_t lastFCcnt=0; | |
2eec55c8 | 1347 | uint8_t fcCounter = 0; |
e0165dcf | 1348 | size_t i; |
1349 | if (size == 0) return 0; | |
1350 | ||
1351 | // prime i to first up transition | |
1352 | for (i = 1; i < size-1; i++) | |
1353 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) | |
1354 | break; | |
1355 | ||
1356 | for (; i < size-1; i++){ | |
1357 | if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ | |
1358 | // new up transition | |
1359 | fcCounter++; | |
2eec55c8 | 1360 | if (fskAdj){ |
1361 | //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) | |
1362 | if (lastFCcnt==5 && fcCounter==9) fcCounter--; | |
1363 | //if fc=9 or 4 add one (for when we get a fc 9 instead of 10 or a 4 instead of a 5) | |
1364 | if ((fcCounter==9) || fcCounter==4) fcCounter++; | |
e0165dcf | 1365 | // save last field clock count (fc/xx) |
2eec55c8 | 1366 | lastFCcnt = fcCounter; |
1367 | } | |
e0165dcf | 1368 | // find which fcLens to save it to: |
1369 | for (int ii=0; ii<10; ii++){ | |
1370 | if (fcLens[ii]==fcCounter){ | |
1371 | fcCnts[ii]++; | |
1372 | fcCounter=0; | |
1373 | break; | |
1374 | } | |
1375 | } | |
1376 | if (fcCounter>0 && fcLensFnd<10){ | |
1377 | //add new fc length | |
1378 | fcCnts[fcLensFnd]++; | |
1379 | fcLens[fcLensFnd++]=fcCounter; | |
1380 | } | |
1381 | fcCounter=0; | |
1382 | } else { | |
1383 | // count sample | |
1384 | fcCounter++; | |
1385 | } | |
1386 | } | |
1387 | ||
1388 | uint8_t best1=9, best2=9, best3=9; | |
1389 | uint16_t maxCnt1=0; | |
1390 | // go through fclens and find which ones are bigest 2 | |
1391 | for (i=0; i<10; i++){ | |
1392 | // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); | |
1393 | // get the 3 best FC values | |
1394 | if (fcCnts[i]>maxCnt1) { | |
1395 | best3=best2; | |
1396 | best2=best1; | |
1397 | maxCnt1=fcCnts[i]; | |
1398 | best1=i; | |
1399 | } else if(fcCnts[i]>fcCnts[best2]){ | |
1400 | best3=best2; | |
1401 | best2=i; | |
1402 | } else if(fcCnts[i]>fcCnts[best3]){ | |
1403 | best3=i; | |
1404 | } | |
1405 | } | |
1406 | uint8_t fcH=0, fcL=0; | |
1407 | if (fcLens[best1]>fcLens[best2]){ | |
1408 | fcH=fcLens[best1]; | |
1409 | fcL=fcLens[best2]; | |
1410 | } else{ | |
1411 | fcH=fcLens[best2]; | |
1412 | fcL=fcLens[best1]; | |
1413 | } | |
1414 | ||
e0165dcf | 1415 | // TODO: take top 3 answers and compare to known Field clocks to get top 2 |
1416 | ||
1417 | uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; | |
1418 | // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); | |
2eec55c8 | 1419 | if (fskAdj) return fcs; |
1420 | return fcLens[best1]; | |
6de43508 | 1421 | } |
1422 | ||
1423 | //by marshmellow - demodulate PSK1 wave | |
1424 | //uses wave lengths (# Samples) | |
1425 | int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) | |
1426 | { | |
e0165dcf | 1427 | if (size == 0) return -1; |
2eec55c8 | 1428 | uint16_t loopCnt = 4096; //don't need to loop through entire array... |
e0165dcf | 1429 | if (*size<loopCnt) loopCnt = *size; |
1430 | ||
1431 | uint8_t curPhase = *invert; | |
1432 | size_t i, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0; | |
1433 | uint8_t fc=0, fullWaveLen=0, tol=1; | |
1434 | uint16_t errCnt=0, waveLenCnt=0; | |
2eec55c8 | 1435 | fc = countFC(dest, *size, 0); |
e0165dcf | 1436 | if (fc!=2 && fc!=4 && fc!=8) return -1; |
1437 | //PrintAndLog("DEBUG: FC: %d",fc); | |
1438 | *clock = DetectPSKClock(dest, *size, *clock); | |
2eec55c8 | 1439 | if (*clock == 0) return -1; |
e0165dcf | 1440 | int avgWaveVal=0, lastAvgWaveVal=0; |
1441 | //find first phase shift | |
1442 | for (i=0; i<loopCnt; i++){ | |
1443 | if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1444 | waveEnd = i+1; | |
1445 | //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); | |
1446 | waveLenCnt = waveEnd-waveStart; | |
1447 | if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave | |
1448 | lastAvgWaveVal = avgWaveVal/(waveLenCnt); | |
1449 | firstFullWave = waveStart; | |
1450 | fullWaveLen=waveLenCnt; | |
1451 | //if average wave value is > graph 0 then it is an up wave or a 1 | |
2eec55c8 | 1452 | if (lastAvgWaveVal > 123) curPhase ^= 1; //fudge graph 0 a little 123 vs 128 |
e0165dcf | 1453 | break; |
1454 | } | |
1455 | waveStart = i+1; | |
1456 | avgWaveVal = 0; | |
1457 | } | |
2eec55c8 | 1458 | avgWaveVal += dest[i+2]; |
e0165dcf | 1459 | } |
1460 | //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); | |
1461 | lastClkBit = firstFullWave; //set start of wave as clock align | |
1462 | //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit); | |
1463 | waveStart = 0; | |
e0165dcf | 1464 | size_t numBits=0; |
1465 | //set skipped bits | |
2eec55c8 | 1466 | memset(dest, curPhase^1, firstFullWave / *clock); |
e0165dcf | 1467 | numBits += (firstFullWave / *clock); |
1468 | dest[numBits++] = curPhase; //set first read bit | |
2eec55c8 | 1469 | for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){ |
e0165dcf | 1470 | //top edge of wave = start of new wave |
1471 | if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ | |
1472 | if (waveStart == 0) { | |
1473 | waveStart = i+1; | |
2eec55c8 | 1474 | waveLenCnt = 0; |
e0165dcf | 1475 | avgWaveVal = dest[i+1]; |
1476 | } else { //waveEnd | |
1477 | waveEnd = i+1; | |
1478 | waveLenCnt = waveEnd-waveStart; | |
1479 | lastAvgWaveVal = avgWaveVal/waveLenCnt; | |
1480 | if (waveLenCnt > fc){ | |
1481 | //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal); | |
2eec55c8 | 1482 | //this wave is a phase shift |
e0165dcf | 1483 | //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc); |
1484 | if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit | |
2eec55c8 | 1485 | curPhase ^= 1; |
e0165dcf | 1486 | dest[numBits++] = curPhase; |
1487 | lastClkBit += *clock; | |
2eec55c8 | 1488 | } else if (i < lastClkBit+10+fc){ |
e0165dcf | 1489 | //noise after a phase shift - ignore |
1490 | } else { //phase shift before supposed to based on clock | |
1491 | errCnt++; | |
2767fc02 | 1492 | dest[numBits++] = 7; |
e0165dcf | 1493 | } |
1494 | } else if (i+1 > lastClkBit + *clock + tol + fc){ | |
1495 | lastClkBit += *clock; //no phase shift but clock bit | |
1496 | dest[numBits++] = curPhase; | |
1497 | } | |
2eec55c8 | 1498 | avgWaveVal = 0; |
1499 | waveStart = i+1; | |
e0165dcf | 1500 | } |
1501 | } | |
2eec55c8 | 1502 | avgWaveVal += dest[i+1]; |
e0165dcf | 1503 | } |
1504 | *size = numBits; | |
1505 | return errCnt; | |
6de43508 | 1506 | } |