-enum emit_mode {
- EMIT_RWD, /* Emit in tag simulation mode, e.g. the source is the RWD */
- EMIT_TAG /* Emit in reader simulation mode, e.g. the source is the TAG */
-};
-static void emit(enum emit_mode mode, int bit)
-{
- if(bit == -1) {
- if(mode == EMIT_RWD) {
- frame_handle_tag(¤t_frame);
- }
- frame_clean(¤t_frame);
- } else if(bit == 0) {
- frame_append_bit(¤t_frame, 0);
- } else if(bit == 1) {
- frame_append_bit(¤t_frame, 1);
- }
-}
-
-void LegicRfSimulate(void)
-{
- /* ADC path high-frequency peak detector, FPGA in high-frequency simulator mode,
- * modulation mode set to 212kHz subcarrier. We are getting the incoming raw
- * envelope waveform on DIN and should send our response on DOUT.
- *
- * The LEGIC RF protocol is pulse-pause-encoding from reader to card, so we'll
- * measure the time between two rising edges on DIN, and no encoding on the
- * subcarrier from card to reader, so we'll just shift out our verbatim data
- * on DOUT, 1 bit is 100us. The time from reader to card frame is still unclear,
- * seems to be 300us-ish.
- */
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_212K);
-
- /* Bitbang the receiver */
- AT91C_BASE_PIOA->PIO_ODR = GPIO_SSC_DIN;
- AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DIN;
-
- setup_timer();
-
- int old_level = 0;
- int active = 0;
-
- while(!BUTTON_PRESS()) {
- int level = !!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN);
- int time = timer->TC_CV;
-
- if(level != old_level) {
- if(level == 1) {
- timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
- if(FUZZ_EQUAL(time, RWD_TIME_1, RWD_TIME_FUZZ)) {
- /* 1 bit */
- emit(EMIT_RWD, 1);
- active = 1;
- LED_B_ON();
- } else if(FUZZ_EQUAL(time, RWD_TIME_0, RWD_TIME_FUZZ)) {
- /* 0 bit */
- emit(EMIT_RWD, 0);
- active = 1;
- LED_B_ON();
- } else if(active) {
- /* invalid */
- emit(EMIT_RWD, -1);
- active = 0;
- LED_B_OFF();
- }
- }
- }
-
- if(time >= (RWD_TIME_1+RWD_TIME_FUZZ) && active) {
- /* Frame end */
- emit(EMIT_RWD, -1);
- active = 0;
- LED_B_OFF();
- }
-
- if(time >= (20*RWD_TIME_1) && (timer->TC_SR & AT91C_TC_CLKSTA)) {
- timer->TC_CCR = AT91C_TC_CLKDIS;
- }
-
-
- old_level = level;
- WDT_HIT();
- }
-}
-