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1 | //----------------------------------------------------------------------------- | |
2 | // (c) 2009 Henryk Plötz <henryk@ploetzli.ch> | |
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 | // LEGIC RF simulation code | |
9 | //----------------------------------------------------------------------------- | |
10 | #include "legicrf.h" | |
11 | ||
12 | static struct legic_frame { | |
13 | int bits; | |
14 | uint32_t data; | |
15 | } current_frame; | |
16 | ||
17 | static enum { | |
18 | STATE_DISCON, | |
19 | STATE_IV, | |
20 | STATE_CON, | |
21 | } legic_state; | |
22 | ||
23 | static crc_t legic_crc; | |
24 | static int legic_read_count; | |
25 | static uint32_t legic_prng_bc; | |
26 | static uint32_t legic_prng_iv; | |
27 | ||
28 | static int legic_phase_drift; | |
29 | static int legic_frame_drift; | |
30 | static int legic_reqresp_drift; | |
31 | ||
32 | AT91PS_TC timer; | |
33 | AT91PS_TC prng_timer; | |
34 | ||
35 | /* | |
36 | static void setup_timer(void) { | |
37 | // Set up Timer 1 to use for measuring time between pulses. Since we're bit-banging | |
38 | // this it won't be terribly accurate but should be good enough. | |
39 | // | |
40 | AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_TC1); | |
41 | timer = AT91C_BASE_TC1; | |
42 | timer->TC_CCR = AT91C_TC_CLKDIS; | |
43 | timer->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK; | |
44 | timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; | |
45 | ||
46 | // | |
47 | // Set up Timer 2 to use for measuring time between frames in | |
48 | // tag simulation mode. Runs 4x faster as Timer 1 | |
49 | // | |
50 | AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_TC2); | |
51 | prng_timer = AT91C_BASE_TC2; | |
52 | prng_timer->TC_CCR = AT91C_TC_CLKDIS; | |
53 | prng_timer->TC_CMR = AT91C_TC_CLKS_TIMER_DIV2_CLOCK; | |
54 | prng_timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; | |
55 | } | |
56 | ||
57 | AT91C_BASE_PMC->PMC_PCER |= (0x1 << 12) | (0x1 << 13) | (0x1 << 14); | |
58 | AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE; | |
59 | ||
60 | // fast clock | |
61 | AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable | |
62 | AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK | // MCK(48MHz)/32 -- tick=1.5mks | |
63 | AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO | AT91C_TC_ACPA_CLEAR | | |
64 | AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET; | |
65 | AT91C_BASE_TC0->TC_RA = 1; | |
66 | AT91C_BASE_TC0->TC_RC = 0xBFFF + 1; // 0xC000 | |
67 | ||
68 | */ | |
69 | ||
70 | // At TIMER_CLOCK3 (MCK/32) | |
71 | //#define RWD_TIME_1 150 /* RWD_TIME_PAUSE off, 80us on = 100us */ | |
72 | //#define RWD_TIME_0 90 /* RWD_TIME_PAUSE off, 40us on = 60us */ | |
73 | //#define RWD_TIME_PAUSE 30 /* 20us */ | |
74 | ||
75 | // testing calculating in (us) microseconds. | |
76 | #define RWD_TIME_1 120 // READER_TIME_PAUSE 20us off, 80us on = 100us 80 * 1.5 == 120ticks | |
77 | #define RWD_TIME_0 60 // READER_TIME_PAUSE 20us off, 40us on = 60us 40 * 1.5 == 60ticks | |
78 | #define RWD_TIME_PAUSE 30 // 20us == 20 * 1.5 == 30ticks */ | |
79 | #define TAG_BIT_PERIOD 150 // 100us == 100 * 1.5 == 150ticks | |
80 | #define TAG_FRAME_WAIT 495 // 330us from READER frame end to TAG frame start. 330 * 1.5 == 495 | |
81 | ||
82 | #define RWD_TIME_FUZZ 20 // rather generous 13us, since the peak detector + hysteresis fuzz quite a bit | |
83 | ||
84 | #define SIM_DIVISOR 586 /* prng_time/SIM_DIVISOR count prng needs to be forwared */ | |
85 | #define SIM_SHIFT 900 /* prng_time+SIM_SHIFT shift of delayed start */ | |
86 | ||
87 | #define OFFSET_LOG 1024 | |
88 | ||
89 | #define FUZZ_EQUAL(value, target, fuzz) ((value) > ((target)-(fuzz)) && (value) < ((target)+(fuzz))) | |
90 | ||
91 | #ifndef SHORT_COIL | |
92 | # define SHORT_COIL LOW(GPIO_SSC_DOUT); | |
93 | #endif | |
94 | #ifndef OPEN_COIL | |
95 | # define OPEN_COIL HIGH(GPIO_SSC_DOUT); | |
96 | #endif | |
97 | ||
98 | uint32_t sendFrameStop = 0; | |
99 | ||
100 | // Pause pulse, off in 20us / 30ticks, | |
101 | // ONE / ZERO bit pulse, | |
102 | // one == 80us / 120ticks | |
103 | // zero == 40us / 60ticks | |
104 | #ifndef COIL_PULSE | |
105 | # define COIL_PULSE(x) \ | |
106 | do { \ | |
107 | SHORT_COIL; \ | |
108 | WaitTicks( (RWD_TIME_PAUSE) ); \ | |
109 | OPEN_COIL; \ | |
110 | WaitTicks((x)); \ | |
111 | } while (0) | |
112 | #endif | |
113 | ||
114 | // ToDo: define a meaningful maximum size for auth_table. The bigger this is, the lower will be the available memory for traces. | |
115 | // Historically it used to be FREE_BUFFER_SIZE, which was 2744. | |
116 | #define LEGIC_CARD_MEMSIZE 1024 | |
117 | static uint8_t* cardmem; | |
118 | ||
119 | static void frame_append_bit(struct legic_frame * const f, uint8_t bit) { | |
120 | // Overflow, won't happen | |
121 | if (f->bits >= 31) return; | |
122 | ||
123 | f->data |= (bit << f->bits); | |
124 | f->bits++; | |
125 | } | |
126 | ||
127 | static void frame_clean(struct legic_frame * const f) { | |
128 | f->data = 0; | |
129 | f->bits = 0; | |
130 | } | |
131 | ||
132 | // Prng works when waiting in 99.1us cycles. | |
133 | // and while sending/receiving in bit frames (100, 60) | |
134 | /*static void CalibratePrng( uint32_t time){ | |
135 | // Calculate Cycles based on timer 100us | |
136 | uint32_t i = (time - sendFrameStop) / 100 ; | |
137 | ||
138 | // substract cycles of finished frames | |
139 | int k = i - legic_prng_count()+1; | |
140 | ||
141 | // substract current frame length, rewind to beginning | |
142 | if ( k > 0 ) | |
143 | legic_prng_forward(k); | |
144 | } | |
145 | */ | |
146 | ||
147 | /* Generate Keystream */ | |
148 | uint32_t get_key_stream(int skip, int count) { | |
149 | uint32_t key = 0; | |
150 | int i; | |
151 | ||
152 | // Use int to enlarge timer tc to 32bit | |
153 | legic_prng_bc += prng_timer->TC_CV; | |
154 | ||
155 | // reset the prng timer. | |
156 | ResetTimer(prng_timer); | |
157 | ||
158 | /* If skip == -1, forward prng time based */ | |
159 | if(skip == -1) { | |
160 | i = (legic_prng_bc + SIM_SHIFT)/SIM_DIVISOR; /* Calculate Cycles based on timer */ | |
161 | i -= legic_prng_count(); /* substract cycles of finished frames */ | |
162 | i -= count; /* substract current frame length, rewind to beginning */ | |
163 | legic_prng_forward(i); | |
164 | } else { | |
165 | legic_prng_forward(skip); | |
166 | } | |
167 | ||
168 | i = (count == 6) ? -1 : legic_read_count; | |
169 | ||
170 | /* Write Time Data into LOG */ | |
171 | // uint8_t *BigBuf = BigBuf_get_addr(); | |
172 | // BigBuf[OFFSET_LOG+128+i] = legic_prng_count(); | |
173 | // BigBuf[OFFSET_LOG+256+i*4] = (legic_prng_bc >> 0) & 0xff; | |
174 | // BigBuf[OFFSET_LOG+256+i*4+1] = (legic_prng_bc >> 8) & 0xff; | |
175 | // BigBuf[OFFSET_LOG+256+i*4+2] = (legic_prng_bc >>16) & 0xff; | |
176 | // BigBuf[OFFSET_LOG+256+i*4+3] = (legic_prng_bc >>24) & 0xff; | |
177 | // BigBuf[OFFSET_LOG+384+i] = count; | |
178 | ||
179 | /* Generate KeyStream */ | |
180 | for(i=0; i<count; i++) { | |
181 | key |= legic_prng_get_bit() << i; | |
182 | legic_prng_forward(1); | |
183 | } | |
184 | return key; | |
185 | } | |
186 | ||
187 | /* Send a frame in tag mode, the FPGA must have been set up by | |
188 | * LegicRfSimulate | |
189 | */ | |
190 | void frame_send_tag(uint16_t response, uint8_t bits, uint8_t crypt) { | |
191 | /* Bitbang the response */ | |
192 | LOW(GPIO_SSC_DOUT); | |
193 | AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT; | |
194 | AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT; | |
195 | ||
196 | /* Use time to crypt frame */ | |
197 | if(crypt) { | |
198 | legic_prng_forward(2); /* TAG_FRAME_WAIT -> shift by 2 */ | |
199 | response ^= legic_prng_get_bits(bits); | |
200 | } | |
201 | ||
202 | /* Wait for the frame start */ | |
203 | WaitUS( TAG_FRAME_WAIT ); | |
204 | ||
205 | uint8_t bit = 0; | |
206 | for(int i = 0; i < bits; i++) { | |
207 | ||
208 | bit = response & 1; | |
209 | response >>= 1; | |
210 | ||
211 | if (bit) | |
212 | HIGH(GPIO_SSC_DOUT); | |
213 | else | |
214 | LOW(GPIO_SSC_DOUT); | |
215 | ||
216 | WaitUS(100); | |
217 | } | |
218 | LOW(GPIO_SSC_DOUT); | |
219 | } | |
220 | ||
221 | /* Send a frame in reader mode, the FPGA must have been set up by | |
222 | * LegicRfReader | |
223 | */ | |
224 | void frame_sendAsReader(uint32_t data, uint8_t bits){ | |
225 | ||
226 | uint32_t starttime = GET_TICKS, send = 0; | |
227 | uint16_t mask = 1; | |
228 | uint8_t prngstart = legic_prng_count() ; | |
229 | ||
230 | // xor lsfr onto data. | |
231 | send = data ^ legic_prng_get_bits(bits); | |
232 | ||
233 | for (; mask < BITMASK(bits); mask <<= 1) { | |
234 | if (send & mask) { | |
235 | COIL_PULSE(RWD_TIME_1); | |
236 | } else { | |
237 | COIL_PULSE(RWD_TIME_0); | |
238 | } | |
239 | } | |
240 | ||
241 | // Final pause to mark the end of the frame | |
242 | COIL_PULSE(0); | |
243 | ||
244 | sendFrameStop = GET_TICKS; | |
245 | uint8_t cmdbytes[] = { | |
246 | bits, | |
247 | BYTEx(data, 0), | |
248 | BYTEx(data, 1), | |
249 | 0x00, | |
250 | 0x00, | |
251 | prngstart, | |
252 | legic_prng_count() | |
253 | }; | |
254 | LogTrace(cmdbytes, sizeof(cmdbytes), starttime, sendFrameStop, NULL, TRUE); | |
255 | } | |
256 | ||
257 | /* Receive a frame from the card in reader emulation mode, the FPGA and | |
258 | * timer must have been set up by LegicRfReader and frame_sendAsReader. | |
259 | * | |
260 | * The LEGIC RF protocol from card to reader does not include explicit | |
261 | * frame start/stop information or length information. The reader must | |
262 | * know beforehand how many bits it wants to receive. (Notably: a card | |
263 | * sending a stream of 0-bits is indistinguishable from no card present.) | |
264 | * | |
265 | * Receive methodology: There is a fancy correlator in hi_read_rx_xcorr, but | |
266 | * I'm not smart enough to use it. Instead I have patched hi_read_tx to output | |
267 | * the ADC signal with hysteresis on SSP_DIN. Bit-bang that signal and look | |
268 | * for edges. Count the edges in each bit interval. If they are approximately | |
269 | * 0 this was a 0-bit, if they are approximately equal to the number of edges | |
270 | * expected for a 212kHz subcarrier, this was a 1-bit. For timing we use the | |
271 | * timer that's still running from frame_sendAsReader in order to get a synchronization | |
272 | * with the frame that we just sent. | |
273 | * | |
274 | * FIXME: Because we're relying on the hysteresis to just do the right thing | |
275 | * the range is severely reduced (and you'll probably also need a good antenna). | |
276 | * So this should be fixed some time in the future for a proper receiver. | |
277 | */ | |
278 | static void frame_receiveAsReader(struct legic_frame * const f, uint8_t bits) { | |
279 | ||
280 | frame_clean(f); | |
281 | if ( bits > 32 ) return; | |
282 | ||
283 | uint8_t i = bits, edges = 0; | |
284 | uint16_t lsfr = 0; | |
285 | uint32_t the_bit = 1, next_bit_at = 0, data; | |
286 | ||
287 | int old_level = 0, level = 0; | |
288 | ||
289 | AT91C_BASE_PIOA->PIO_ODR = GPIO_SSC_DIN; | |
290 | AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DIN; | |
291 | ||
292 | // calibrate the prng. | |
293 | // | |
294 | legic_prng_forward(2); | |
295 | ||
296 | // precompute the cipher | |
297 | uint8_t prngstart = legic_prng_count() ; | |
298 | ||
299 | data = lsfr = legic_prng_get_bits(bits); | |
300 | ||
301 | //FIXED time between sending frame and now listening frame. 330us | |
302 | // 387 = 0x19 0001 1001 | |
303 | // 480 = 0x19 | |
304 | // 500 = 0x1C 0001 1100 | |
305 | uint32_t starttime = GET_TICKS; | |
306 | //uint16_t mywait = TAG_FRAME_WAIT - (starttime - sendFrameStop); | |
307 | uint16_t mywait = 495 - (starttime - sendFrameStop); | |
308 | if ( bits == 6) | |
309 | WaitTicks( 495 - 9 ); | |
310 | else { | |
311 | //Dbprintf("WAIT %d", mywait ); | |
312 | WaitTicks( mywait ); | |
313 | } | |
314 | ||
315 | next_bit_at = GET_TICKS + TAG_BIT_PERIOD; | |
316 | ||
317 | while ( i-- ){ | |
318 | edges = 0; | |
319 | uint8_t adjust = 0; | |
320 | while ( GET_TICKS < next_bit_at) { | |
321 | ||
322 | level = (AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN); | |
323 | ||
324 | if (level != old_level) | |
325 | ++edges; | |
326 | ||
327 | old_level = level; | |
328 | ||
329 | if(edges > 20 && adjust == 0) { | |
330 | next_bit_at -= 15; | |
331 | adjust = 1; | |
332 | } | |
333 | } | |
334 | ||
335 | next_bit_at += TAG_BIT_PERIOD; | |
336 | ||
337 | // We expect 42 edges == ONE | |
338 | //if (edges > 20 && edges < 64) | |
339 | if ( edges > 20 ) | |
340 | data ^= the_bit; | |
341 | ||
342 | the_bit <<= 1; | |
343 | } | |
344 | ||
345 | // output | |
346 | f->data = data; | |
347 | f->bits = bits; | |
348 | ||
349 | uint8_t cmdbytes[] = { | |
350 | bits, | |
351 | BYTEx(data,0), | |
352 | BYTEx(data,1), | |
353 | BYTEx(data, 0) ^ BYTEx(lsfr,0), | |
354 | BYTEx(data, 1) ^ BYTEx(lsfr,1), | |
355 | prngstart, | |
356 | legic_prng_count() | |
357 | }; | |
358 | LogTrace(cmdbytes, sizeof(cmdbytes), starttime, GET_TICKS, NULL, FALSE); | |
359 | } | |
360 | ||
361 | // Setup pm3 as a Legic Reader | |
362 | static uint32_t setup_phase_reader(uint8_t iv) { | |
363 | ||
364 | // Switch on carrier and let the tag charge for 1ms | |
365 | HIGH(GPIO_SSC_DOUT); | |
366 | WaitUS(1000); | |
367 | ||
368 | ResetTicks(); | |
369 | ||
370 | // no keystream yet | |
371 | legic_prng_init(0); | |
372 | ||
373 | // send IV handshake | |
374 | frame_sendAsReader(iv, 7); | |
375 | ||
376 | // Now both tag and reader has same IV. Prng can start. | |
377 | legic_prng_init(iv); | |
378 | ||
379 | frame_receiveAsReader(¤t_frame, 6); | |
380 | ||
381 | // fixed delay before sending ack. | |
382 | WaitTicks(366); // 244us | |
383 | legic_prng_forward(1); //240us / 100 == 2.4 iterations | |
384 | ||
385 | // Send obsfuscated acknowledgment frame. | |
386 | // 0x19 = 0x18 MIM22, 0x01 LSB READCMD | |
387 | // 0x39 = 0x38 MIM256, MIM1024 0x01 LSB READCMD | |
388 | switch ( current_frame.data ) { | |
389 | case 0x0D: frame_sendAsReader(0x19, 6); break; | |
390 | case 0x1D: | |
391 | case 0x3D: frame_sendAsReader(0x39, 6); break; | |
392 | default: break; | |
393 | } | |
394 | return current_frame.data; | |
395 | } | |
396 | ||
397 | static void LegicCommonInit(void) { | |
398 | ||
399 | FpgaDownloadAndGo(FPGA_BITSTREAM_HF); | |
400 | FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); | |
401 | SetAdcMuxFor(GPIO_MUXSEL_HIPKD); | |
402 | ||
403 | /* Bitbang the transmitter */ | |
404 | LOW(GPIO_SSC_DOUT); | |
405 | AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT; | |
406 | AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT; | |
407 | ||
408 | // reserve a cardmem, meaning we can use the tracelog function in bigbuff easier. | |
409 | cardmem = BigBuf_malloc(LEGIC_CARD_MEMSIZE); | |
410 | memset(cardmem, 0x00, LEGIC_CARD_MEMSIZE); | |
411 | ||
412 | clear_trace(); | |
413 | set_tracing(TRUE); | |
414 | crc_init(&legic_crc, 4, 0x19 >> 1, 0x5, 0); | |
415 | ||
416 | StartTicks(); | |
417 | } | |
418 | ||
419 | // Switch off carrier, make sure tag is reset | |
420 | static void switch_off_tag_rwd(void) { | |
421 | LOW(GPIO_SSC_DOUT); | |
422 | WaitUS(200); | |
423 | WDT_HIT(); | |
424 | Dbprintf("Exit Switch_off_tag_rwd"); | |
425 | } | |
426 | ||
427 | // calculate crc4 for a legic READ command | |
428 | // 5,8,10 address size. | |
429 | static uint32_t legic4Crc(uint8_t legicCmd, uint16_t byte_index, uint8_t value, uint8_t cmd_sz) { | |
430 | crc_clear(&legic_crc); | |
431 | //uint32_t temp = (value << cmd_sz) | (byte_index << 1) | legicCmd; | |
432 | //crc_update(&legic_crc, temp, cmd_sz + 8 ); | |
433 | crc_update(&legic_crc, 1, 1); /* CMD_READ */ | |
434 | crc_update(&legic_crc, byte_index, cmd_sz-1); | |
435 | crc_update(&legic_crc, value, 8); | |
436 | return crc_finish(&legic_crc); | |
437 | } | |
438 | ||
439 | int legic_read_byte(int byte_index, int cmd_sz) { | |
440 | ||
441 | // (us)| ticks | |
442 | // ------------- | |
443 | // 330 | 495 | |
444 | // 460 | 690 | |
445 | // 258 | 387 | |
446 | // 244 | 366 | |
447 | WaitTicks(387); | |
448 | legic_prng_forward(4); // 460 / 100 = 4.6 iterations | |
449 | ||
450 | uint8_t byte = 0, crc = 0, calcCrc = 0; | |
451 | uint32_t cmd = (byte_index << 1) | LEGIC_READ; | |
452 | ||
453 | frame_sendAsReader(cmd, cmd_sz); | |
454 | frame_receiveAsReader(¤t_frame, 12); | |
455 | ||
456 | byte = BYTEx(current_frame.data, 0); | |
457 | calcCrc = legic4Crc(LEGIC_READ, byte_index, byte, cmd_sz); | |
458 | crc = BYTEx(current_frame.data, 1); | |
459 | ||
460 | if( calcCrc != crc ) { | |
461 | Dbprintf("!!! crc mismatch: expected %x but got %x !!!", calcCrc, crc); | |
462 | return -1; | |
463 | } | |
464 | return byte; | |
465 | } | |
466 | ||
467 | /* | |
468 | * - assemble a write_cmd_frame with crc and send it | |
469 | * - wait until the tag sends back an ACK ('1' bit unencrypted) | |
470 | * - forward the prng based on the timing | |
471 | */ | |
472 | //int legic_write_byte(int byte, int addr, int addr_sz, int PrngCorrection) { | |
473 | int legic_write_byte(uint8_t byte, uint16_t addr, uint8_t addr_sz) { | |
474 | ||
475 | //do not write UID, CRC at offset 0-4. | |
476 | if (addr <= 4) return 0; | |
477 | ||
478 | // crc | |
479 | crc_clear(&legic_crc); | |
480 | crc_update(&legic_crc, 0, 1); /* CMD_WRITE */ | |
481 | crc_update(&legic_crc, addr, addr_sz); | |
482 | crc_update(&legic_crc, byte, 8); | |
483 | uint32_t crc = crc_finish(&legic_crc); | |
484 | ||
485 | uint32_t crc2 = legic4Crc(LEGIC_WRITE, addr, byte, addr_sz+1); | |
486 | if ( crc != crc2 ) | |
487 | Dbprintf("crc is missmatch"); | |
488 | ||
489 | // send write command | |
490 | uint32_t cmd = ((crc <<(addr_sz+1+8)) //CRC | |
491 | |(byte <<(addr_sz+1)) //Data | |
492 | |(addr <<1) //Address | |
493 | | LEGIC_WRITE); //CMD = Write | |
494 | ||
495 | uint32_t cmd_sz = addr_sz+1+8+4; //crc+data+cmd | |
496 | ||
497 | legic_prng_forward(2); /* we wait anyways */ | |
498 | ||
499 | WaitUS(TAG_FRAME_WAIT); | |
500 | ||
501 | frame_sendAsReader(cmd, cmd_sz); | |
502 | ||
503 | // wllm-rbnt doesnt have these | |
504 | AT91C_BASE_PIOA->PIO_ODR = GPIO_SSC_DIN; | |
505 | AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DIN; | |
506 | ||
507 | // wait for ack | |
508 | int t, old_level = 0, edges = 0; | |
509 | int next_bit_at = 0; | |
510 | ||
511 | WaitUS(TAG_FRAME_WAIT); | |
512 | ||
513 | for( t = 0; t < 80; ++t) { | |
514 | edges = 0; | |
515 | next_bit_at += TAG_BIT_PERIOD; | |
516 | while(timer->TC_CV < next_bit_at) { | |
517 | int level = (AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN); | |
518 | if(level != old_level) | |
519 | edges++; | |
520 | ||
521 | old_level = level; | |
522 | } | |
523 | if(edges > 20 && edges < 60) { /* expected are 42 edges */ | |
524 | int t = timer->TC_CV; | |
525 | int c = t / TAG_BIT_PERIOD; | |
526 | ||
527 | ResetTimer(timer); | |
528 | legic_prng_forward(c); | |
529 | return 0; | |
530 | } | |
531 | } | |
532 | ||
533 | ResetTimer(timer); | |
534 | return -1; | |
535 | } | |
536 | ||
537 | int LegicRfReader(int offset, int bytes, int iv) { | |
538 | ||
539 | uint16_t byte_index = 0; | |
540 | uint8_t cmd_sz = 0, isOK = 1; | |
541 | int card_sz = 0; | |
542 | ||
543 | LegicCommonInit(); | |
544 | ||
545 | uint32_t tag_type = setup_phase_reader(iv); | |
546 | ||
547 | switch_off_tag_rwd(); | |
548 | ||
549 | switch(tag_type) { | |
550 | case 0x0d: | |
551 | if ( MF_DBGLEVEL >= 2) DbpString("MIM22 card found, reading card"); | |
552 | cmd_sz = 6; | |
553 | card_sz = 22; | |
554 | break; | |
555 | case 0x1d: | |
556 | if ( MF_DBGLEVEL >= 2) DbpString("MIM256 card found, reading card"); | |
557 | cmd_sz = 9; | |
558 | card_sz = 256; | |
559 | break; | |
560 | case 0x3d: | |
561 | if ( MF_DBGLEVEL >= 2) DbpString("MIM1024 card found, reading card"); | |
562 | cmd_sz = 11; | |
563 | card_sz = 1024; | |
564 | break; | |
565 | default: | |
566 | if ( MF_DBGLEVEL >= 1) Dbprintf("Unknown card format: %x", tag_type); | |
567 | isOK = 0; | |
568 | goto OUT; | |
569 | break; | |
570 | } | |
571 | if (bytes == -1) | |
572 | bytes = card_sz; | |
573 | ||
574 | if (bytes + offset >= card_sz) | |
575 | bytes = card_sz - offset; | |
576 | ||
577 | // Start setup and read bytes. | |
578 | setup_phase_reader(iv); | |
579 | ||
580 | LED_B_ON(); | |
581 | while (byte_index < bytes) { | |
582 | int r = legic_read_byte(byte_index + offset, cmd_sz); | |
583 | ||
584 | if (r == -1 || BUTTON_PRESS()) { | |
585 | if ( MF_DBGLEVEL >= 3) DbpString("operation aborted"); | |
586 | isOK = 0; | |
587 | goto OUT; | |
588 | } | |
589 | cardmem[++byte_index] = r; | |
590 | WDT_HIT(); | |
591 | } | |
592 | ||
593 | OUT: | |
594 | WDT_HIT(); | |
595 | switch_off_tag_rwd(); | |
596 | LEDsoff(); | |
597 | uint8_t len = (bytes & 0x3FF); | |
598 | cmd_send(CMD_ACK,isOK,len,0,cardmem,len); | |
599 | return 0; | |
600 | } | |
601 | ||
602 | /*int _LegicRfWriter(int offset, int bytes, int addr_sz, uint8_t *BigBuf, int RoundBruteforceValue) { | |
603 | int byte_index=0; | |
604 | ||
605 | LED_B_ON(); | |
606 | setup_phase_reader(iv); | |
607 | //legic_prng_forward(2); | |
608 | while(byte_index < bytes) { | |
609 | int r; | |
610 | ||
611 | //check if the DCF should be changed | |
612 | if ( (offset == 0x05) && (bytes == 0x02) ) { | |
613 | //write DCF in reverse order (addr 0x06 before 0x05) | |
614 | r = legic_write_byte(BigBuf[(0x06-byte_index)], (0x06-byte_index), addr_sz, RoundBruteforceValue); | |
615 | //legic_prng_forward(1); | |
616 | if(r == 0) { | |
617 | byte_index++; | |
618 | r = legic_write_byte(BigBuf[(0x06-byte_index)], (0x06-byte_index), addr_sz, RoundBruteforceValue); | |
619 | } | |
620 | //legic_prng_forward(1); | |
621 | } | |
622 | else { | |
623 | r = legic_write_byte(BigBuf[byte_index+offset], byte_index+offset, addr_sz, RoundBruteforceValue); | |
624 | } | |
625 | if((r != 0) || BUTTON_PRESS()) { | |
626 | Dbprintf("operation aborted @ 0x%03.3x", byte_index); | |
627 | switch_off_tag_rwd(); | |
628 | LED_B_OFF(); | |
629 | LED_C_OFF(); | |
630 | return -1; | |
631 | } | |
632 | ||
633 | WDT_HIT(); | |
634 | byte_index++; | |
635 | if(byte_index & 0x10) LED_C_ON(); else LED_C_OFF(); | |
636 | } | |
637 | LED_B_OFF(); | |
638 | LED_C_OFF(); | |
639 | DbpString("write successful"); | |
640 | return 0; | |
641 | }*/ | |
642 | ||
643 | void LegicRfWriter(int offset, int bytes, int iv) { | |
644 | ||
645 | int byte_index = 0, addr_sz = 0; | |
646 | ||
647 | LegicCommonInit(); | |
648 | ||
649 | if ( MF_DBGLEVEL >= 2) DbpString("setting up legic card"); | |
650 | ||
651 | uint32_t tag_type = setup_phase_reader(iv); | |
652 | ||
653 | switch_off_tag_rwd(); | |
654 | ||
655 | switch(tag_type) { | |
656 | case 0x0d: | |
657 | if(offset+bytes > 22) { | |
658 | Dbprintf("Error: can not write to 0x%03.3x on MIM22", offset + bytes); | |
659 | return; | |
660 | } | |
661 | addr_sz = 5; | |
662 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM22 card found, writing 0x%02.2x - 0x%02.2x ...", offset, offset + bytes); | |
663 | break; | |
664 | case 0x1d: | |
665 | if(offset+bytes > 0x100) { | |
666 | Dbprintf("Error: can not write to 0x%03.3x on MIM256", offset + bytes); | |
667 | return; | |
668 | } | |
669 | addr_sz = 8; | |
670 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM256 card found, writing 0x%02.2x - 0x%02.2x ...", offset, offset + bytes); | |
671 | break; | |
672 | case 0x3d: | |
673 | if(offset+bytes > 0x400) { | |
674 | Dbprintf("Error: can not write to 0x%03.3x on MIM1024", offset + bytes); | |
675 | return; | |
676 | } | |
677 | addr_sz = 10; | |
678 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM1024 card found, writing 0x%03.3x - 0x%03.3x ...", offset, offset + bytes); | |
679 | break; | |
680 | default: | |
681 | Dbprintf("No or unknown card found, aborting"); | |
682 | return; | |
683 | } | |
684 | ||
685 | LED_B_ON(); | |
686 | setup_phase_reader(iv); | |
687 | int r = 0; | |
688 | while(byte_index < bytes) { | |
689 | ||
690 | //check if the DCF should be changed | |
691 | if ( ((byte_index+offset) == 0x05) && (bytes >= 0x02) ) { | |
692 | //write DCF in reverse order (addr 0x06 before 0x05) | |
693 | r = legic_write_byte(cardmem[(0x06-byte_index)], (0x06-byte_index), addr_sz); | |
694 | ||
695 | // write second byte on success... | |
696 | if(r == 0) { | |
697 | byte_index++; | |
698 | r = legic_write_byte(cardmem[(0x06-byte_index)], (0x06-byte_index), addr_sz); | |
699 | } | |
700 | } | |
701 | else { | |
702 | r = legic_write_byte(cardmem[byte_index+offset], byte_index+offset, addr_sz); | |
703 | } | |
704 | ||
705 | if ((r != 0) || BUTTON_PRESS()) { | |
706 | Dbprintf("operation aborted @ 0x%03.3x", byte_index); | |
707 | switch_off_tag_rwd(); | |
708 | LEDsoff(); | |
709 | return; | |
710 | } | |
711 | ||
712 | WDT_HIT(); | |
713 | byte_index++; | |
714 | } | |
715 | LEDsoff(); | |
716 | if ( MF_DBGLEVEL >= 1) DbpString("write successful"); | |
717 | } | |
718 | ||
719 | void LegicRfRawWriter(int address, int byte, int iv) { | |
720 | ||
721 | int byte_index = 0, addr_sz = 0; | |
722 | ||
723 | LegicCommonInit(); | |
724 | ||
725 | if ( MF_DBGLEVEL >= 2) DbpString("setting up legic card"); | |
726 | ||
727 | uint32_t tag_type = setup_phase_reader(iv); | |
728 | ||
729 | switch_off_tag_rwd(); | |
730 | ||
731 | switch(tag_type) { | |
732 | case 0x0d: | |
733 | if(address > 22) { | |
734 | Dbprintf("Error: can not write to 0x%03.3x on MIM22", address); | |
735 | return; | |
736 | } | |
737 | addr_sz = 5; | |
738 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM22 card found, writing at addr 0x%02.2x - value 0x%02.2x ...", address, byte); | |
739 | break; | |
740 | case 0x1d: | |
741 | if(address > 0x100) { | |
742 | Dbprintf("Error: can not write to 0x%03.3x on MIM256", address); | |
743 | return; | |
744 | } | |
745 | addr_sz = 8; | |
746 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM256 card found, writing at addr 0x%02.2x - value 0x%02.2x ...", address, byte); | |
747 | break; | |
748 | case 0x3d: | |
749 | if(address > 0x400) { | |
750 | Dbprintf("Error: can not write to 0x%03.3x on MIM1024", address); | |
751 | return; | |
752 | } | |
753 | addr_sz = 10; | |
754 | if ( MF_DBGLEVEL >= 2) Dbprintf("MIM1024 card found, writing at addr 0x%03.3x - value 0x%03.3x ...", address, byte); | |
755 | break; | |
756 | default: | |
757 | Dbprintf("No or unknown card found, aborting"); | |
758 | return; | |
759 | } | |
760 | ||
761 | Dbprintf("integer value: %d address: %d addr_sz: %d", byte, address, addr_sz); | |
762 | LED_B_ON(); | |
763 | ||
764 | setup_phase_reader(iv); | |
765 | ||
766 | int r = legic_write_byte(byte, address, addr_sz); | |
767 | ||
768 | if((r != 0) || BUTTON_PRESS()) { | |
769 | Dbprintf("operation aborted @ 0x%03.3x (%1d)", byte_index, r); | |
770 | switch_off_tag_rwd(); | |
771 | LEDsoff(); | |
772 | return; | |
773 | } | |
774 | ||
775 | LEDsoff(); | |
776 | if ( MF_DBGLEVEL >= 1) DbpString("write successful"); | |
777 | } | |
778 | ||
779 | /* Handle (whether to respond) a frame in tag mode | |
780 | * Only called when simulating a tag. | |
781 | */ | |
782 | static void frame_handle_tag(struct legic_frame const * const f) | |
783 | { | |
784 | uint8_t *BigBuf = BigBuf_get_addr(); | |
785 | ||
786 | /* First Part of Handshake (IV) */ | |
787 | if(f->bits == 7) { | |
788 | ||
789 | LED_C_ON(); | |
790 | ||
791 | // Reset prng timer | |
792 | ResetTimer(prng_timer); | |
793 | ||
794 | legic_prng_init(f->data); | |
795 | frame_send_tag(0x3d, 6, 1); /* 0x3d^0x26 = 0x1B */ | |
796 | legic_state = STATE_IV; | |
797 | legic_read_count = 0; | |
798 | legic_prng_bc = 0; | |
799 | legic_prng_iv = f->data; | |
800 | ||
801 | ||
802 | ResetTimer(timer); | |
803 | WaitUS(280); | |
804 | return; | |
805 | } | |
806 | ||
807 | /* 0x19==??? */ | |
808 | if(legic_state == STATE_IV) { | |
809 | int local_key = get_key_stream(3, 6); | |
810 | int xored = 0x39 ^ local_key; | |
811 | if((f->bits == 6) && (f->data == xored)) { | |
812 | legic_state = STATE_CON; | |
813 | ||
814 | ResetTimer(timer); | |
815 | WaitUS(200); | |
816 | return; | |
817 | ||
818 | } else { | |
819 | legic_state = STATE_DISCON; | |
820 | LED_C_OFF(); | |
821 | Dbprintf("iv: %02x frame: %02x key: %02x xored: %02x", legic_prng_iv, f->data, local_key, xored); | |
822 | return; | |
823 | } | |
824 | } | |
825 | ||
826 | /* Read */ | |
827 | if(f->bits == 11) { | |
828 | if(legic_state == STATE_CON) { | |
829 | int key = get_key_stream(2, 11); //legic_phase_drift, 11); | |
830 | int addr = f->data ^ key; addr = addr >> 1; | |
831 | int data = BigBuf[addr]; | |
832 | int hash = legic4Crc(LEGIC_READ, addr, data, 11) << 8; | |
833 | BigBuf[OFFSET_LOG+legic_read_count] = (uint8_t)addr; | |
834 | legic_read_count++; | |
835 | ||
836 | //Dbprintf("Data:%03.3x, key:%03.3x, addr: %03.3x, read_c:%u", f->data, key, addr, read_c); | |
837 | legic_prng_forward(legic_reqresp_drift); | |
838 | ||
839 | frame_send_tag(hash | data, 12, 1); | |
840 | ||
841 | ResetTimer(timer); | |
842 | legic_prng_forward(2); | |
843 | WaitUS(180); | |
844 | return; | |
845 | } | |
846 | } | |
847 | ||
848 | /* Write */ | |
849 | if(f->bits == 23) { | |
850 | int key = get_key_stream(-1, 23); //legic_frame_drift, 23); | |
851 | int addr = f->data ^ key; addr = addr >> 1; addr = addr & 0x3ff; | |
852 | int data = f->data ^ key; data = data >> 11; data = data & 0xff; | |
853 | ||
854 | /* write command */ | |
855 | legic_state = STATE_DISCON; | |
856 | LED_C_OFF(); | |
857 | Dbprintf("write - addr: %x, data: %x", addr, data); | |
858 | return; | |
859 | } | |
860 | ||
861 | if(legic_state != STATE_DISCON) { | |
862 | Dbprintf("Unexpected: sz:%u, Data:%03.3x, State:%u, Count:%u", f->bits, f->data, legic_state, legic_read_count); | |
863 | int i; | |
864 | Dbprintf("IV: %03.3x", legic_prng_iv); | |
865 | for(i = 0; i<legic_read_count; i++) { | |
866 | Dbprintf("Read Nb: %u, Addr: %u", i, BigBuf[OFFSET_LOG+i]); | |
867 | } | |
868 | ||
869 | for(i = -1; i<legic_read_count; i++) { | |
870 | uint32_t t; | |
871 | t = BigBuf[OFFSET_LOG+256+i*4]; | |
872 | t |= BigBuf[OFFSET_LOG+256+i*4+1] << 8; | |
873 | t |= BigBuf[OFFSET_LOG+256+i*4+2] <<16; | |
874 | t |= BigBuf[OFFSET_LOG+256+i*4+3] <<24; | |
875 | ||
876 | Dbprintf("Cycles: %u, Frame Length: %u, Time: %u", | |
877 | BigBuf[OFFSET_LOG+128+i], | |
878 | BigBuf[OFFSET_LOG+384+i], | |
879 | t); | |
880 | } | |
881 | } | |
882 | legic_state = STATE_DISCON; | |
883 | legic_read_count = 0; | |
884 | SpinDelay(10); | |
885 | LED_C_OFF(); | |
886 | return; | |
887 | } | |
888 | ||
889 | /* Read bit by bit untill full frame is received | |
890 | * Call to process frame end answer | |
891 | */ | |
892 | static void emit(int bit) { | |
893 | ||
894 | switch (bit) { | |
895 | case 1: | |
896 | frame_append_bit(¤t_frame, 1); | |
897 | break; | |
898 | case 0: | |
899 | frame_append_bit(¤t_frame, 0); | |
900 | break; | |
901 | default: | |
902 | if(current_frame.bits <= 4) { | |
903 | frame_clean(¤t_frame); | |
904 | } else { | |
905 | frame_handle_tag(¤t_frame); | |
906 | frame_clean(¤t_frame); | |
907 | } | |
908 | WDT_HIT(); | |
909 | break; | |
910 | } | |
911 | } | |
912 | ||
913 | void LegicRfSimulate(int phase, int frame, int reqresp) | |
914 | { | |
915 | /* ADC path high-frequency peak detector, FPGA in high-frequency simulator mode, | |
916 | * modulation mode set to 212kHz subcarrier. We are getting the incoming raw | |
917 | * envelope waveform on DIN and should send our response on DOUT. | |
918 | * | |
919 | * The LEGIC RF protocol is pulse-pause-encoding from reader to card, so we'll | |
920 | * measure the time between two rising edges on DIN, and no encoding on the | |
921 | * subcarrier from card to reader, so we'll just shift out our verbatim data | |
922 | * on DOUT, 1 bit is 100us. The time from reader to card frame is still unclear, | |
923 | * seems to be 300us-ish. | |
924 | */ | |
925 | ||
926 | legic_phase_drift = phase; | |
927 | legic_frame_drift = frame; | |
928 | legic_reqresp_drift = reqresp; | |
929 | ||
930 | FpgaDownloadAndGo(FPGA_BITSTREAM_HF); | |
931 | SetAdcMuxFor(GPIO_MUXSEL_HIPKD); | |
932 | FpgaSetupSsc(); | |
933 | FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_212K); | |
934 | ||
935 | /* Bitbang the receiver */ | |
936 | AT91C_BASE_PIOA->PIO_ODR = GPIO_SSC_DIN; | |
937 | AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DIN; | |
938 | ||
939 | //setup_timer(); | |
940 | crc_init(&legic_crc, 4, 0x19 >> 1, 0x5, 0); | |
941 | ||
942 | int old_level = 0; | |
943 | int active = 0; | |
944 | legic_state = STATE_DISCON; | |
945 | ||
946 | LED_B_ON(); | |
947 | DbpString("Starting Legic emulator, press button to end"); | |
948 | ||
949 | while(!BUTTON_PRESS() && !usb_poll_validate_length()) { | |
950 | int level = !!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN); | |
951 | int time = timer->TC_CV; | |
952 | ||
953 | if(level != old_level) { | |
954 | if(level == 1) { | |
955 | timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; | |
956 | ||
957 | if (FUZZ_EQUAL(time, RWD_TIME_1, RWD_TIME_FUZZ)) { | |
958 | /* 1 bit */ | |
959 | emit(1); | |
960 | active = 1; | |
961 | LED_A_ON(); | |
962 | } else if (FUZZ_EQUAL(time, RWD_TIME_0, RWD_TIME_FUZZ)) { | |
963 | /* 0 bit */ | |
964 | emit(0); | |
965 | active = 1; | |
966 | LED_A_ON(); | |
967 | } else if (active) { | |
968 | /* invalid */ | |
969 | emit(-1); | |
970 | active = 0; | |
971 | LED_A_OFF(); | |
972 | } | |
973 | } | |
974 | } | |
975 | ||
976 | /* Frame end */ | |
977 | if(time >= (RWD_TIME_1+RWD_TIME_FUZZ) && active) { | |
978 | emit(-1); | |
979 | active = 0; | |
980 | LED_A_OFF(); | |
981 | } | |
982 | ||
983 | if(time >= (20*RWD_TIME_1) && (timer->TC_SR & AT91C_TC_CLKSTA)) { | |
984 | timer->TC_CCR = AT91C_TC_CLKDIS; | |
985 | } | |
986 | ||
987 | old_level = level; | |
988 | WDT_HIT(); | |
989 | } | |
990 | if ( MF_DBGLEVEL >= 1) DbpString("Stopped"); | |
991 | LEDsoff(); | |
992 | } | |
993 | ||
994 | //----------------------------------------------------------------------------- | |
995 | // Code up a string of octets at layer 2 (including CRC, we don't generate | |
996 | // that here) so that they can be transmitted to the reader. Doesn't transmit | |
997 | // them yet, just leaves them ready to send in ToSend[]. | |
998 | //----------------------------------------------------------------------------- | |
999 | // static void CodeLegicAsTag(const uint8_t *cmd, int len) | |
1000 | // { | |
1001 | // int i; | |
1002 | ||
1003 | // ToSendReset(); | |
1004 | ||
1005 | // // Transmit a burst of ones, as the initial thing that lets the | |
1006 | // // reader get phase sync. This (TR1) must be > 80/fs, per spec, | |
1007 | // // but tag that I've tried (a Paypass) exceeds that by a fair bit, | |
1008 | // // so I will too. | |
1009 | // for(i = 0; i < 20; i++) { | |
1010 | // ToSendStuffBit(1); | |
1011 | // ToSendStuffBit(1); | |
1012 | // ToSendStuffBit(1); | |
1013 | // ToSendStuffBit(1); | |
1014 | // } | |
1015 | ||
1016 | // // Send SOF. | |
1017 | // for(i = 0; i < 10; i++) { | |
1018 | // ToSendStuffBit(0); | |
1019 | // ToSendStuffBit(0); | |
1020 | // ToSendStuffBit(0); | |
1021 | // ToSendStuffBit(0); | |
1022 | // } | |
1023 | // for(i = 0; i < 2; i++) { | |
1024 | // ToSendStuffBit(1); | |
1025 | // ToSendStuffBit(1); | |
1026 | // ToSendStuffBit(1); | |
1027 | // ToSendStuffBit(1); | |
1028 | // } | |
1029 | ||
1030 | // for(i = 0; i < len; i++) { | |
1031 | // int j; | |
1032 | // uint8_t b = cmd[i]; | |
1033 | ||
1034 | // // Start bit | |
1035 | // ToSendStuffBit(0); | |
1036 | // ToSendStuffBit(0); | |
1037 | // ToSendStuffBit(0); | |
1038 | // ToSendStuffBit(0); | |
1039 | ||
1040 | // // Data bits | |
1041 | // for(j = 0; j < 8; j++) { | |
1042 | // if(b & 1) { | |
1043 | // ToSendStuffBit(1); | |
1044 | // ToSendStuffBit(1); | |
1045 | // ToSendStuffBit(1); | |
1046 | // ToSendStuffBit(1); | |
1047 | // } else { | |
1048 | // ToSendStuffBit(0); | |
1049 | // ToSendStuffBit(0); | |
1050 | // ToSendStuffBit(0); | |
1051 | // ToSendStuffBit(0); | |
1052 | // } | |
1053 | // b >>= 1; | |
1054 | // } | |
1055 | ||
1056 | // // Stop bit | |
1057 | // ToSendStuffBit(1); | |
1058 | // ToSendStuffBit(1); | |
1059 | // ToSendStuffBit(1); | |
1060 | // ToSendStuffBit(1); | |
1061 | // } | |
1062 | ||
1063 | // // Send EOF. | |
1064 | // for(i = 0; i < 10; i++) { | |
1065 | // ToSendStuffBit(0); | |
1066 | // ToSendStuffBit(0); | |
1067 | // ToSendStuffBit(0); | |
1068 | // ToSendStuffBit(0); | |
1069 | // } | |
1070 | // for(i = 0; i < 2; i++) { | |
1071 | // ToSendStuffBit(1); | |
1072 | // ToSendStuffBit(1); | |
1073 | // ToSendStuffBit(1); | |
1074 | // ToSendStuffBit(1); | |
1075 | // } | |
1076 | ||
1077 | // // Convert from last byte pos to length | |
1078 | // ToSendMax++; | |
1079 | // } | |
1080 | ||
1081 | //----------------------------------------------------------------------------- | |
1082 | // The software UART that receives commands from the reader, and its state | |
1083 | // variables. | |
1084 | //----------------------------------------------------------------------------- | |
1085 | static struct { | |
1086 | enum { | |
1087 | STATE_UNSYNCD, | |
1088 | STATE_GOT_FALLING_EDGE_OF_SOF, | |
1089 | STATE_AWAITING_START_BIT, | |
1090 | STATE_RECEIVING_DATA | |
1091 | } state; | |
1092 | uint16_t shiftReg; | |
1093 | int bitCnt; | |
1094 | int byteCnt; | |
1095 | int byteCntMax; | |
1096 | int posCnt; | |
1097 | uint8_t *output; | |
1098 | } Uart; | |
1099 | ||
1100 | /* Receive & handle a bit coming from the reader. | |
1101 | * | |
1102 | * This function is called 4 times per bit (every 2 subcarrier cycles). | |
1103 | * Subcarrier frequency fs is 212kHz, 1/fs = 4,72us, i.e. function is called every 9,44us | |
1104 | * | |
1105 | * LED handling: | |
1106 | * LED A -> ON once we have received the SOF and are expecting the rest. | |
1107 | * LED A -> OFF once we have received EOF or are in error state or unsynced | |
1108 | * | |
1109 | * Returns: true if we received a EOF | |
1110 | * false if we are still waiting for some more | |
1111 | */ | |
1112 | // static RAMFUNC int HandleLegicUartBit(uint8_t bit) | |
1113 | // { | |
1114 | // switch(Uart.state) { | |
1115 | // case STATE_UNSYNCD: | |
1116 | // if(!bit) { | |
1117 | // // we went low, so this could be the beginning of an SOF | |
1118 | // Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF; | |
1119 | // Uart.posCnt = 0; | |
1120 | // Uart.bitCnt = 0; | |
1121 | // } | |
1122 | // break; | |
1123 | ||
1124 | // case STATE_GOT_FALLING_EDGE_OF_SOF: | |
1125 | // Uart.posCnt++; | |
1126 | // if(Uart.posCnt == 2) { // sample every 4 1/fs in the middle of a bit | |
1127 | // if(bit) { | |
1128 | // if(Uart.bitCnt > 9) { | |
1129 | // // we've seen enough consecutive | |
1130 | // // zeros that it's a valid SOF | |
1131 | // Uart.posCnt = 0; | |
1132 | // Uart.byteCnt = 0; | |
1133 | // Uart.state = STATE_AWAITING_START_BIT; | |
1134 | // LED_A_ON(); // Indicate we got a valid SOF | |
1135 | // } else { | |
1136 | // // didn't stay down long enough | |
1137 | // // before going high, error | |
1138 | // Uart.state = STATE_UNSYNCD; | |
1139 | // } | |
1140 | // } else { | |
1141 | // // do nothing, keep waiting | |
1142 | // } | |
1143 | // Uart.bitCnt++; | |
1144 | // } | |
1145 | // if(Uart.posCnt >= 4) Uart.posCnt = 0; | |
1146 | // if(Uart.bitCnt > 12) { | |
1147 | // // Give up if we see too many zeros without | |
1148 | // // a one, too. | |
1149 | // LED_A_OFF(); | |
1150 | // Uart.state = STATE_UNSYNCD; | |
1151 | // } | |
1152 | // break; | |
1153 | ||
1154 | // case STATE_AWAITING_START_BIT: | |
1155 | // Uart.posCnt++; | |
1156 | // if(bit) { | |
1157 | // if(Uart.posCnt > 50/2) { // max 57us between characters = 49 1/fs, max 3 etus after low phase of SOF = 24 1/fs | |
1158 | // // stayed high for too long between | |
1159 | // // characters, error | |
1160 | // Uart.state = STATE_UNSYNCD; | |
1161 | // } | |
1162 | // } else { | |
1163 | // // falling edge, this starts the data byte | |
1164 | // Uart.posCnt = 0; | |
1165 | // Uart.bitCnt = 0; | |
1166 | // Uart.shiftReg = 0; | |
1167 | // Uart.state = STATE_RECEIVING_DATA; | |
1168 | // } | |
1169 | // break; | |
1170 | ||
1171 | // case STATE_RECEIVING_DATA: | |
1172 | // Uart.posCnt++; | |
1173 | // if(Uart.posCnt == 2) { | |
1174 | // // time to sample a bit | |
1175 | // Uart.shiftReg >>= 1; | |
1176 | // if(bit) { | |
1177 | // Uart.shiftReg |= 0x200; | |
1178 | // } | |
1179 | // Uart.bitCnt++; | |
1180 | // } | |
1181 | // if(Uart.posCnt >= 4) { | |
1182 | // Uart.posCnt = 0; | |
1183 | // } | |
1184 | // if(Uart.bitCnt == 10) { | |
1185 | // if((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001)) | |
1186 | // { | |
1187 | // // this is a data byte, with correct | |
1188 | // // start and stop bits | |
1189 | // Uart.output[Uart.byteCnt] = (Uart.shiftReg >> 1) & 0xff; | |
1190 | // Uart.byteCnt++; | |
1191 | ||
1192 | // if(Uart.byteCnt >= Uart.byteCntMax) { | |
1193 | // // Buffer overflowed, give up | |
1194 | // LED_A_OFF(); | |
1195 | // Uart.state = STATE_UNSYNCD; | |
1196 | // } else { | |
1197 | // // so get the next byte now | |
1198 | // Uart.posCnt = 0; | |
1199 | // Uart.state = STATE_AWAITING_START_BIT; | |
1200 | // } | |
1201 | // } else if (Uart.shiftReg == 0x000) { | |
1202 | // // this is an EOF byte | |
1203 | // LED_A_OFF(); // Finished receiving | |
1204 | // Uart.state = STATE_UNSYNCD; | |
1205 | // if (Uart.byteCnt != 0) { | |
1206 | // return TRUE; | |
1207 | // } | |
1208 | // } else { | |
1209 | // // this is an error | |
1210 | // LED_A_OFF(); | |
1211 | // Uart.state = STATE_UNSYNCD; | |
1212 | // } | |
1213 | // } | |
1214 | // break; | |
1215 | ||
1216 | // default: | |
1217 | // LED_A_OFF(); | |
1218 | // Uart.state = STATE_UNSYNCD; | |
1219 | // break; | |
1220 | // } | |
1221 | ||
1222 | // return FALSE; | |
1223 | // } | |
1224 | ||
1225 | ||
1226 | static void UartReset() { | |
1227 | Uart.byteCntMax = 3; | |
1228 | Uart.state = STATE_UNSYNCD; | |
1229 | Uart.byteCnt = 0; | |
1230 | Uart.bitCnt = 0; | |
1231 | Uart.posCnt = 0; | |
1232 | memset(Uart.output, 0x00, 3); | |
1233 | } | |
1234 | ||
1235 | // static void UartInit(uint8_t *data) { | |
1236 | // Uart.output = data; | |
1237 | // UartReset(); | |
1238 | // } | |
1239 | ||
1240 | //============================================================================= | |
1241 | // An LEGIC reader. We take layer two commands, code them | |
1242 | // appropriately, and then send them to the tag. We then listen for the | |
1243 | // tag's response, which we leave in the buffer to be demodulated on the | |
1244 | // PC side. | |
1245 | //============================================================================= | |
1246 | ||
1247 | static struct { | |
1248 | enum { | |
1249 | DEMOD_UNSYNCD, | |
1250 | DEMOD_PHASE_REF_TRAINING, | |
1251 | DEMOD_AWAITING_FALLING_EDGE_OF_SOF, | |
1252 | DEMOD_GOT_FALLING_EDGE_OF_SOF, | |
1253 | DEMOD_AWAITING_START_BIT, | |
1254 | DEMOD_RECEIVING_DATA | |
1255 | } state; | |
1256 | int bitCount; | |
1257 | int posCount; | |
1258 | int thisBit; | |
1259 | uint16_t shiftReg; | |
1260 | uint8_t *output; | |
1261 | int len; | |
1262 | int sumI; | |
1263 | int sumQ; | |
1264 | } Demod; | |
1265 | ||
1266 | /* | |
1267 | * Handles reception of a bit from the tag | |
1268 | * | |
1269 | * This function is called 2 times per bit (every 4 subcarrier cycles). | |
1270 | * Subcarrier frequency fs is 212kHz, 1/fs = 4,72us, i.e. function is called every 9,44us | |
1271 | * | |
1272 | * LED handling: | |
1273 | * LED C -> ON once we have received the SOF and are expecting the rest. | |
1274 | * LED C -> OFF once we have received EOF or are unsynced | |
1275 | * | |
1276 | * Returns: true if we received a EOF | |
1277 | * false if we are still waiting for some more | |
1278 | * | |
1279 | */ | |
1280 | ||
1281 | #ifndef SUBCARRIER_DETECT_THRESHOLD | |
1282 | # define SUBCARRIER_DETECT_THRESHOLD 8 | |
1283 | #endif | |
1284 | ||
1285 | // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq))) | |
1286 | #ifndef CHECK_FOR_SUBCARRIER | |
1287 | # define CHECK_FOR_SUBCARRIER() { v = MAX(ai, aq) + MIN(halfci, halfcq); } | |
1288 | #endif | |
1289 | ||
1290 | // The soft decision on the bit uses an estimate of just the | |
1291 | // quadrant of the reference angle, not the exact angle. | |
1292 | // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq))) | |
1293 | #define MAKE_SOFT_DECISION() { \ | |
1294 | if(Demod.sumI > 0) \ | |
1295 | v = ci; \ | |
1296 | else \ | |
1297 | v = -ci; \ | |
1298 | \ | |
1299 | if(Demod.sumQ > 0) \ | |
1300 | v += cq; \ | |
1301 | else \ | |
1302 | v -= cq; \ | |
1303 | \ | |
1304 | } | |
1305 | ||
1306 | static RAMFUNC int HandleLegicSamplesDemod(int ci, int cq) | |
1307 | { | |
1308 | int v = 0; | |
1309 | int ai = ABS(ci); | |
1310 | int aq = ABS(cq); | |
1311 | int halfci = (ai >> 1); | |
1312 | int halfcq = (aq >> 1); | |
1313 | ||
1314 | switch(Demod.state) { | |
1315 | case DEMOD_UNSYNCD: | |
1316 | ||
1317 | CHECK_FOR_SUBCARRIER() | |
1318 | ||
1319 | if(v > SUBCARRIER_DETECT_THRESHOLD) { // subcarrier detected | |
1320 | Demod.state = DEMOD_PHASE_REF_TRAINING; | |
1321 | Demod.sumI = ci; | |
1322 | Demod.sumQ = cq; | |
1323 | Demod.posCount = 1; | |
1324 | } | |
1325 | break; | |
1326 | ||
1327 | case DEMOD_PHASE_REF_TRAINING: | |
1328 | if(Demod.posCount < 8) { | |
1329 | ||
1330 | CHECK_FOR_SUBCARRIER() | |
1331 | ||
1332 | if (v > SUBCARRIER_DETECT_THRESHOLD) { | |
1333 | // set the reference phase (will code a logic '1') by averaging over 32 1/fs. | |
1334 | // note: synchronization time > 80 1/fs | |
1335 | Demod.sumI += ci; | |
1336 | Demod.sumQ += cq; | |
1337 | ++Demod.posCount; | |
1338 | } else { | |
1339 | // subcarrier lost | |
1340 | Demod.state = DEMOD_UNSYNCD; | |
1341 | } | |
1342 | } else { | |
1343 | Demod.state = DEMOD_AWAITING_FALLING_EDGE_OF_SOF; | |
1344 | } | |
1345 | break; | |
1346 | ||
1347 | case DEMOD_AWAITING_FALLING_EDGE_OF_SOF: | |
1348 | ||
1349 | MAKE_SOFT_DECISION() | |
1350 | ||
1351 | //Dbprintf("ICE: %d %d %d %d %d", v, Demod.sumI, Demod.sumQ, ci, cq ); | |
1352 | // logic '0' detected | |
1353 | if (v <= 0) { | |
1354 | ||
1355 | Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF; | |
1356 | ||
1357 | // start of SOF sequence | |
1358 | Demod.posCount = 0; | |
1359 | } else { | |
1360 | // maximum length of TR1 = 200 1/fs | |
1361 | if(Demod.posCount > 25*2) Demod.state = DEMOD_UNSYNCD; | |
1362 | } | |
1363 | ++Demod.posCount; | |
1364 | break; | |
1365 | ||
1366 | case DEMOD_GOT_FALLING_EDGE_OF_SOF: | |
1367 | ++Demod.posCount; | |
1368 | ||
1369 | MAKE_SOFT_DECISION() | |
1370 | ||
1371 | if(v > 0) { | |
1372 | // low phase of SOF too short (< 9 etu). Note: spec is >= 10, but FPGA tends to "smear" edges | |
1373 | if(Demod.posCount < 10*2) { | |
1374 | Demod.state = DEMOD_UNSYNCD; | |
1375 | } else { | |
1376 | LED_C_ON(); // Got SOF | |
1377 | Demod.state = DEMOD_AWAITING_START_BIT; | |
1378 | Demod.posCount = 0; | |
1379 | Demod.len = 0; | |
1380 | } | |
1381 | } else { | |
1382 | // low phase of SOF too long (> 12 etu) | |
1383 | if(Demod.posCount > 13*2) { | |
1384 | Demod.state = DEMOD_UNSYNCD; | |
1385 | LED_C_OFF(); | |
1386 | } | |
1387 | } | |
1388 | break; | |
1389 | ||
1390 | case DEMOD_AWAITING_START_BIT: | |
1391 | ++Demod.posCount; | |
1392 | ||
1393 | MAKE_SOFT_DECISION() | |
1394 | ||
1395 | if(v > 0) { | |
1396 | // max 19us between characters = 16 1/fs, max 3 etu after low phase of SOF = 24 1/fs | |
1397 | if(Demod.posCount > 3*2) { | |
1398 | Demod.state = DEMOD_UNSYNCD; | |
1399 | LED_C_OFF(); | |
1400 | } | |
1401 | } else { | |
1402 | // start bit detected | |
1403 | Demod.bitCount = 0; | |
1404 | Demod.posCount = 1; // this was the first half | |
1405 | Demod.thisBit = v; | |
1406 | Demod.shiftReg = 0; | |
1407 | Demod.state = DEMOD_RECEIVING_DATA; | |
1408 | } | |
1409 | break; | |
1410 | ||
1411 | case DEMOD_RECEIVING_DATA: | |
1412 | ||
1413 | MAKE_SOFT_DECISION() | |
1414 | ||
1415 | if(Demod.posCount == 0) { | |
1416 | // first half of bit | |
1417 | Demod.thisBit = v; | |
1418 | Demod.posCount = 1; | |
1419 | } else { | |
1420 | // second half of bit | |
1421 | Demod.thisBit += v; | |
1422 | Demod.shiftReg >>= 1; | |
1423 | // logic '1' | |
1424 | if(Demod.thisBit > 0) | |
1425 | Demod.shiftReg |= 0x200; | |
1426 | ||
1427 | ++Demod.bitCount; | |
1428 | ||
1429 | if(Demod.bitCount == 10) { | |
1430 | ||
1431 | uint16_t s = Demod.shiftReg; | |
1432 | ||
1433 | if((s & 0x200) && !(s & 0x001)) { | |
1434 | // stop bit == '1', start bit == '0' | |
1435 | uint8_t b = (s >> 1); | |
1436 | Demod.output[Demod.len] = b; | |
1437 | ++Demod.len; | |
1438 | Demod.state = DEMOD_AWAITING_START_BIT; | |
1439 | } else { | |
1440 | Demod.state = DEMOD_UNSYNCD; | |
1441 | LED_C_OFF(); | |
1442 | ||
1443 | if(s == 0x000) { | |
1444 | // This is EOF (start, stop and all data bits == '0' | |
1445 | return TRUE; | |
1446 | } | |
1447 | } | |
1448 | } | |
1449 | Demod.posCount = 0; | |
1450 | } | |
1451 | break; | |
1452 | ||
1453 | default: | |
1454 | Demod.state = DEMOD_UNSYNCD; | |
1455 | LED_C_OFF(); | |
1456 | break; | |
1457 | } | |
1458 | return FALSE; | |
1459 | } | |
1460 | ||
1461 | // Clear out the state of the "UART" that receives from the tag. | |
1462 | static void DemodReset() { | |
1463 | Demod.len = 0; | |
1464 | Demod.state = DEMOD_UNSYNCD; | |
1465 | Demod.posCount = 0; | |
1466 | Demod.sumI = 0; | |
1467 | Demod.sumQ = 0; | |
1468 | Demod.bitCount = 0; | |
1469 | Demod.thisBit = 0; | |
1470 | Demod.shiftReg = 0; | |
1471 | memset(Demod.output, 0x00, 3); | |
1472 | } | |
1473 | ||
1474 | static void DemodInit(uint8_t *data) { | |
1475 | Demod.output = data; | |
1476 | DemodReset(); | |
1477 | } | |
1478 | ||
1479 | /* | |
1480 | * Demodulate the samples we received from the tag, also log to tracebuffer | |
1481 | * quiet: set to 'TRUE' to disable debug output | |
1482 | */ | |
1483 | #define LEGIC_DMA_BUFFER_SIZE 256 | |
1484 | static void GetSamplesForLegicDemod(int n, bool quiet) | |
1485 | { | |
1486 | int max = 0; | |
1487 | bool gotFrame = FALSE; | |
1488 | int lastRxCounter = LEGIC_DMA_BUFFER_SIZE; | |
1489 | int ci, cq, samples = 0; | |
1490 | ||
1491 | BigBuf_free(); | |
1492 | ||
1493 | // And put the FPGA in the appropriate mode | |
1494 | FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_QUARTER_FREQ); | |
1495 | ||
1496 | // The response (tag -> reader) that we're receiving. | |
1497 | // Set up the demodulator for tag -> reader responses. | |
1498 | DemodInit(BigBuf_malloc(MAX_FRAME_SIZE)); | |
1499 | ||
1500 | // The DMA buffer, used to stream samples from the FPGA | |
1501 | int8_t *dmaBuf = (int8_t*) BigBuf_malloc(LEGIC_DMA_BUFFER_SIZE); | |
1502 | int8_t *upTo = dmaBuf; | |
1503 | ||
1504 | // Setup and start DMA. | |
1505 | if ( !FpgaSetupSscDma((uint8_t*) dmaBuf, LEGIC_DMA_BUFFER_SIZE) ){ | |
1506 | if (MF_DBGLEVEL > 1) Dbprintf("FpgaSetupSscDma failed. Exiting"); | |
1507 | return; | |
1508 | } | |
1509 | ||
1510 | // Signal field is ON with the appropriate LED: | |
1511 | LED_D_ON(); | |
1512 | for(;;) { | |
1513 | int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR; | |
1514 | if(behindBy > max) max = behindBy; | |
1515 | ||
1516 | while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (LEGIC_DMA_BUFFER_SIZE-1)) > 2) { | |
1517 | ci = upTo[0]; | |
1518 | cq = upTo[1]; | |
1519 | upTo += 2; | |
1520 | if(upTo >= dmaBuf + LEGIC_DMA_BUFFER_SIZE) { | |
1521 | upTo = dmaBuf; | |
1522 | AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo; | |
1523 | AT91C_BASE_PDC_SSC->PDC_RNCR = LEGIC_DMA_BUFFER_SIZE; | |
1524 | } | |
1525 | lastRxCounter -= 2; | |
1526 | if(lastRxCounter <= 0) | |
1527 | lastRxCounter = LEGIC_DMA_BUFFER_SIZE; | |
1528 | ||
1529 | samples += 2; | |
1530 | ||
1531 | gotFrame = HandleLegicSamplesDemod(ci , cq ); | |
1532 | if ( gotFrame ) | |
1533 | break; | |
1534 | } | |
1535 | ||
1536 | if(samples > n || gotFrame) | |
1537 | break; | |
1538 | } | |
1539 | ||
1540 | FpgaDisableSscDma(); | |
1541 | ||
1542 | if (!quiet && Demod.len == 0) { | |
1543 | Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d", | |
1544 | max, | |
1545 | samples, | |
1546 | gotFrame, | |
1547 | Demod.len, | |
1548 | Demod.sumI, | |
1549 | Demod.sumQ | |
1550 | ); | |
1551 | } | |
1552 | ||
1553 | //Tracing | |
1554 | if (Demod.len > 0) { | |
1555 | uint8_t parity[MAX_PARITY_SIZE] = {0x00}; | |
1556 | LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE); | |
1557 | } | |
1558 | } | |
1559 | //----------------------------------------------------------------------------- | |
1560 | // Transmit the command (to the tag) that was placed in ToSend[]. | |
1561 | //----------------------------------------------------------------------------- | |
1562 | static void TransmitForLegic(void) | |
1563 | { | |
1564 | int c; | |
1565 | ||
1566 | FpgaSetupSsc(); | |
1567 | ||
1568 | while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) | |
1569 | AT91C_BASE_SSC->SSC_THR = 0xff; | |
1570 | ||
1571 | // Signal field is ON with the appropriate Red LED | |
1572 | LED_D_ON(); | |
1573 | ||
1574 | // Signal we are transmitting with the Green LED | |
1575 | LED_B_ON(); | |
1576 | FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD); | |
1577 | ||
1578 | for(c = 0; c < 10;) { | |
1579 | if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { | |
1580 | AT91C_BASE_SSC->SSC_THR = 0xff; | |
1581 | c++; | |
1582 | } | |
1583 | if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { | |
1584 | volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; | |
1585 | (void)r; | |
1586 | } | |
1587 | WDT_HIT(); | |
1588 | } | |
1589 | ||
1590 | c = 0; | |
1591 | for(;;) { | |
1592 | if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { | |
1593 | AT91C_BASE_SSC->SSC_THR = ToSend[c]; | |
1594 | legic_prng_forward(1); // forward the lfsr | |
1595 | c++; | |
1596 | if(c >= ToSendMax) { | |
1597 | break; | |
1598 | } | |
1599 | } | |
1600 | if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { | |
1601 | volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; | |
1602 | (void)r; | |
1603 | } | |
1604 | WDT_HIT(); | |
1605 | } | |
1606 | LED_B_OFF(); | |
1607 | } | |
1608 | ||
1609 | ||
1610 | //----------------------------------------------------------------------------- | |
1611 | // Code a layer 2 command (string of octets, including CRC) into ToSend[], | |
1612 | // so that it is ready to transmit to the tag using TransmitForLegic(). | |
1613 | //----------------------------------------------------------------------------- | |
1614 | static void CodeLegicBitsAsReader(const uint8_t *cmd, uint8_t cmdlen, int bits) | |
1615 | { | |
1616 | int i, j; | |
1617 | uint8_t b; | |
1618 | ||
1619 | ToSendReset(); | |
1620 | ||
1621 | // Send SOF | |
1622 | for(i = 0; i < 7; i++) | |
1623 | ToSendStuffBit(1); | |
1624 | ||
1625 | ||
1626 | for(i = 0; i < cmdlen; i++) { | |
1627 | // Start bit | |
1628 | ToSendStuffBit(0); | |
1629 | ||
1630 | // Data bits | |
1631 | b = cmd[i]; | |
1632 | for(j = 0; j < bits; j++) { | |
1633 | if(b & 1) { | |
1634 | ToSendStuffBit(1); | |
1635 | } else { | |
1636 | ToSendStuffBit(0); | |
1637 | } | |
1638 | b >>= 1; | |
1639 | } | |
1640 | } | |
1641 | ||
1642 | // Convert from last character reference to length | |
1643 | ++ToSendMax; | |
1644 | } | |
1645 | ||
1646 | /** | |
1647 | Convenience function to encode, transmit and trace Legic comms | |
1648 | **/ | |
1649 | static void CodeAndTransmitLegicAsReader(const uint8_t *cmd, uint8_t cmdlen, int bits) | |
1650 | { | |
1651 | CodeLegicBitsAsReader(cmd, cmdlen, bits); | |
1652 | TransmitForLegic(); | |
1653 | if (tracing) { | |
1654 | uint8_t parity[1] = {0x00}; | |
1655 | LogTrace(cmd, cmdlen, 0, 0, parity, TRUE); | |
1656 | } | |
1657 | } | |
1658 | ||
1659 | int ice_legic_select_card() | |
1660 | { | |
1661 | //int cmd_size=0, card_size=0; | |
1662 | uint8_t wakeup[] = { 0x7F }; | |
1663 | uint8_t getid[] = {0x19}; | |
1664 | ||
1665 | //legic_prng_init(SESSION_IV); | |
1666 | ||
1667 | // first, wake up the tag, 7bits | |
1668 | CodeAndTransmitLegicAsReader(wakeup, sizeof(wakeup), 7); | |
1669 | ||
1670 | GetSamplesForLegicDemod(1000, TRUE); | |
1671 | ||
1672 | //frame_receiveAsReader(¤t_frame, 6, 1); | |
1673 | ||
1674 | legic_prng_forward(1); /* we wait anyways */ | |
1675 | ||
1676 | //while(timer->TC_CV < 387) ; /* ~ 258us */ | |
1677 | //frame_sendAsReader(0x19, 6); | |
1678 | CodeAndTransmitLegicAsReader(getid, sizeof(getid), 8); | |
1679 | GetSamplesForLegicDemod(1000, TRUE); | |
1680 | ||
1681 | //if (Demod.len < 14) return 2; | |
1682 | Dbprintf("CARD TYPE: %02x LEN: %d", Demod.output[0], Demod.len); | |
1683 | ||
1684 | switch(Demod.output[0]) { | |
1685 | case 0x1d: | |
1686 | DbpString("MIM 256 card found"); | |
1687 | // cmd_size = 9; | |
1688 | // card_size = 256; | |
1689 | break; | |
1690 | case 0x3d: | |
1691 | DbpString("MIM 1024 card found"); | |
1692 | // cmd_size = 11; | |
1693 | // card_size = 1024; | |
1694 | break; | |
1695 | default: | |
1696 | return -1; | |
1697 | } | |
1698 | ||
1699 | // if(bytes == -1) | |
1700 | // bytes = card_size; | |
1701 | ||
1702 | // if(bytes + offset >= card_size) | |
1703 | // bytes = card_size - offset; | |
1704 | ||
1705 | FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); | |
1706 | set_tracing(FALSE); | |
1707 | return 1; | |
1708 | } | |
1709 | ||
1710 | // Set up LEGIC communication | |
1711 | void ice_legic_setup() { | |
1712 | ||
1713 | // standard things. | |
1714 | FpgaDownloadAndGo(FPGA_BITSTREAM_HF); | |
1715 | BigBuf_free(); BigBuf_Clear_ext(false); | |
1716 | clear_trace(); | |
1717 | set_tracing(TRUE); | |
1718 | DemodReset(); | |
1719 | UartReset(); | |
1720 | ||
1721 | // Set up the synchronous serial port | |
1722 | FpgaSetupSsc(); | |
1723 | ||
1724 | // connect Demodulated Signal to ADC: | |
1725 | SetAdcMuxFor(GPIO_MUXSEL_HIPKD); | |
1726 | ||
1727 | // Signal field is on with the appropriate LED | |
1728 | LED_D_ON(); | |
1729 | FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD); | |
1730 | SpinDelay(20); | |
1731 | // Start the timer | |
1732 | //StartCountSspClk(); | |
1733 | ||
1734 | // initalize CRC | |
1735 | crc_init(&legic_crc, 4, 0x19 >> 1, 0x5, 0); | |
1736 | ||
1737 | // initalize prng | |
1738 | legic_prng_init(0); | |
1739 | } |