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-rw-r--r--openpcd/firmware/src/tc.c35
-rw-r--r--openpcd/firmware/src/tc.h4
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
personal git repositories of Harald Welte. Your mileage may vary