+// -------------------------------------------------------------------------
+// Mifare timer. Uses ssp_clk from FPGA
+// -------------------------------------------------------------------------
+void StartCountMifare()
+{
+ AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_TC0) | (1 << AT91C_ID_TC1) | (1 << AT91C_ID_TC2); // Enable Clock to all timers
+ AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_TIOA1 // XC0 Clock = TIOA1
+ | AT91C_TCB_TC1XC1S_NONE // XC1 Clock = none
+ | AT91C_TCB_TC2XC2S_TIOA0; // XC2 Clock = TIOA0
+
+ // configure TC1 to create a short pulse on TIOA1 when a rising edge on TIOB1 (= ssp_clk from FPGA) occurs:
+ AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // disable TC1
+ AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_TIMER_DIV1_CLOCK // TC1 Clock = MCK(48MHz)/2 = 24MHz
+ | AT91C_TC_CPCSTOP // Stop clock on RC compare
+ | AT91C_TC_EEVTEDG_RISING // Trigger on rising edge of Event
+ | AT91C_TC_EEVT_TIOB // Event-Source: TIOB1 (= ssc_clk from FPGA = 13,56MHz / 16)
+ | AT91C_TC_ENETRG // Enable external trigger event
+ | AT91C_TC_WAVESEL_UP // Upmode without automatic trigger on RC compare
+ | AT91C_TC_WAVE // Waveform Mode
+ | AT91C_TC_AEEVT_SET // Set TIOA1 on external event
+ | AT91C_TC_ACPC_CLEAR; // Clear TIOA1 on RC Compare
+ AT91C_BASE_TC1->TC_RC = 0x04; // RC Compare value = 0x04
+
+ // use TC0 to count TIOA1 pulses
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // disable TC0
+ AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_XC0 // TC0 clock = XC0 clock = TIOA1
+ | AT91C_TC_WAVE // Waveform Mode
+ | AT91C_TC_WAVESEL_UP // just count
+ | AT91C_TC_ACPA_CLEAR // Clear TIOA0 on RA Compare
+ | AT91C_TC_ACPC_SET; // Set TIOA0 on RC Compare
+ AT91C_BASE_TC0->TC_RA = 1; // RA Compare value = 1; pulse width to TC2
+ AT91C_BASE_TC0->TC_RC = 0; // RC Compare value = 0; increment TC2 on overflow
+
+ // use TC2 to count TIOA0 pulses (giving us a 32bit counter (TC0/TC2) clocked by ssp_clk)
+ AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKDIS; // disable TC2
+ AT91C_BASE_TC2->TC_CMR = AT91C_TC_CLKS_XC2 // TC2 clock = XC2 clock = TIOA0
+ | AT91C_TC_WAVE // Waveform Mode
+ | AT91C_TC_WAVESEL_UP; // just count
+
+
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN; // enable TC0
+ AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN; // enable TC1
+ AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN; // enable TC2
+
+ // activate the ISO14443 part of the FPGA. We need the clock and frame signals.
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+ // synchronize the counter with the ssp_frame signal.
+ while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME); // wait for ssp_frame to be low
+ while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME)); // sync on rising edge of ssp_frame (= start of transfer)
+
+ AT91C_BASE_TCB->TCB_BCR = 1; // assert Sync (set all timers to 0 on next active clock edge)
+}
+
+
+uint32_t RAMFUNC GetCountMifare(){
+ uint32_t tmp_count;
+ tmp_count = (AT91C_BASE_TC2->TC_CV << 16) | AT91C_BASE_TC0->TC_CV;
+ if ((tmp_count & 0xffff) == 0) { //small chance that we may have missed an increment in TC2
+ return (AT91C_BASE_TC2->TC_CV << 16);
+ }
+ else {
+ return tmp_count;
+ }
+}