diff options
| -rw-r--r-- | openpcd/firmware/src/tc.c | 35 | ||||
| -rw-r--r-- | openpcd/firmware/src/tc.h | 4 |
2 files changed, 38 insertions, 1 deletions
diff --git a/openpcd/firmware/src/tc.c b/openpcd/firmware/src/tc.c index 4a0189b..2f4628a 100644 --- a/openpcd/firmware/src/tc.c +++ b/openpcd/firmware/src/tc.c @@ -3,7 +3,17 @@ * * This idea of this code is to feed the 13.56MHz carrier clock of RC632 * into TCLK1, which is routed to XC1. Then configure TC0 to divide this - * clock by + * clock by a configurable divider. + * + * PICC Simulator Side: + * In order to support responding to synchronous frames (REQA/WUPA/ANTICOL), + * we need a second Timer/Counter (TC1). This unit is reset by an external + * event (rising edge of modulation pause PCD->PICC) connected to TIOB2, and + * counts up to a configurable number of carrier clock cycles (RA). Once the + * RA value is reached, TIOA2 will see a rising edge. This rising edge will + * be interconnected to TF (Tx Frame) of the SSC to start transmitting our + * synchronous response. + * */ #include <lib_AT91SAM7.h> @@ -35,6 +45,13 @@ void tc_cdiv_phase_add(int16_t inc) } } +#ifdef CONFIG_PICCSIM +void tc_fdt_set(u_int16_t count) +{ + tcb->TC_TC2.TC_RA = count; +} +#endif + void tc_cdiv_init(void) { /* Cfg PA28(TCLK1), PA0(TIOA0), PA1(TIOB0), PA20(TCLK2) as Periph B */ @@ -66,6 +83,22 @@ void tc_cdiv_init(void) tc_cdiv_set_divider(128); +#ifdef CONFIG_PICCSIM + AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, AT91C_PA15_TF, + AT91C_PA26_TIOA2, AT91C_PA17_TIOB2); + AT91F_PMC_EnablePeriphClock(AT91C_BASE_PMC, + ((unsigned int) 1 << AT91C_ID_TC2)); + /* Clock XC1, Wave Mode, No automatic reset on RC comp + * TIOA2 in RA comp = set, TIOA2 on RC comp = clear, + * TIOB2 as input, EEVT = TIOB2, Reset/Trigger on EEVT */ + tcb->TCB_TC2.TC_CMR = AT91C_TC_CLKS_XC1 | AT91C_TC_WAVE | + AT91C_TC_WAVESEL_UP | + AT91C_TC_ACPA_SET | AT91C_ACPC_CLEAR | + AT91C_TC_BEEVT_NONE | AT91C_TC_BCPB_NONE | + AT91C_TC_EEVT_TIOB | AT91C_TC_ETRGEDG_RISING | + AT91C_TC_ENETRG ; +#endif + /* Reset to start timers */ tcb->TCB_BCR = 1; } diff --git a/openpcd/firmware/src/tc.h b/openpcd/firmware/src/tc.h index 763992c..e7aa7e4 100644 --- a/openpcd/firmware/src/tc.h +++ b/openpcd/firmware/src/tc.h @@ -21,4 +21,8 @@ extern void tc_cdiv_print(void); extern void tc_cdiv_init(void); extern void tc_cdiv_fini(void); +#ifdef CONFIG_PICCSIM +extern void tc_fdt_set(u_int16_t count); +#endif + #endif |