data[len - 1] <<= 1;
}
-int32_t le24toh (uint8_t data[3])
-{
- return (data[2] << 16) | (data[1] << 8) | data[0];
-}
-
void LEDsoff()
{
LED_A_OFF();
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 (= ssp_clk from FPGA = 13,56MHz/16)
+ | AT91C_TC_EEVT_TIOB // Event-Source: TIOB1 (= ssp_clk from FPGA = 13,56MHz/16 ... 13,56MHz/4)
| 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
+ AT91C_BASE_TC1->TC_RC = 0x02; // RC Compare value = 0x02
// use TC0 to count TIOA1 pulses
AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // disable TC0
AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN; // enable TC2
//
- // synchronize the counter with the ssp_frame signal. Note: FPGA must be in any iso14443 mode, otherwise SSC_FRAME and SSC_CLK signals would not be present
+ // synchronize the counter with the ssp_frame signal. Note: FPGA must be in a FPGA mode with SSC transfer, otherwise SSC_FRAME and SSC_CLK signals would not be present
//
while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME)); // wait for ssp_frame to go high (start of frame)
while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME); // wait for ssp_frame to be low
}
-uint32_t RAMFUNC GetCountSspClk(){
- uint32_t tmp_count;
- tmp_count = (AT91C_BASE_TC2->TC_CV << 16) | AT91C_BASE_TC0->TC_CV;
- if ((tmp_count & 0x0000ffff) == 0) { //small chance that we may have missed an increment in TC2
- return (AT91C_BASE_TC2->TC_CV << 16);
- }
- else {
- return tmp_count;
- }
+uint32_t GetCountSspClk(){
+ uint32_t hi, lo;
+
+ do {
+ hi = AT91C_BASE_TC2->TC_CV;
+ lo = AT91C_BASE_TC0->TC_CV;
+ } while(hi != AT91C_BASE_TC2->TC_CV);
+
+ return (hi << 16) | lo;
}
// -------------------------------------------------------------------------
-// Timer for bitbanging, or LF stuff when you need a very precis timer
+// Timer for bitbanging, or LF stuff when you need a very precis timer
// 1us = 1.5ticks
// -------------------------------------------------------------------------
void StartTicks(void){
- //initialization of the timer
- // tc1 is higher 0xFFFF0000
- // tc0 is lower 0x0000FFFF
+ // initialization of the timer
AT91C_BASE_PMC->PMC_PCER |= (1 << AT91C_ID_TC0) | (1 << AT91C_ID_TC1);
AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
+
+ // disable TC0 and TC1 for re-configuration
AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS;
+ AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS;
+
+ // first configure TC1 (higher, 0xFFFF0000) 16 bit counter
+ AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_XC1; // just connect to TIOA0 from TC0
+ AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; // re-enable timer and wait for TC0
+
+ // second configure TC0 (lower, 0x0000FFFF) 16 bit counter
AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK | // MCK(48MHz) / 32
- AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO | AT91C_TC_ACPA_CLEAR |
- AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET;
- AT91C_BASE_TC0->TC_RA = 1;
- AT91C_BASE_TC0->TC_RC = 0;
+ AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO |
+ AT91C_TC_ACPA_CLEAR | // RA comperator clears TIOA (carry bit)
+ AT91C_TC_ACPC_SET | // RC comperator sets TIOA (carry bit)
+ AT91C_TC_ASWTRG_SET; // SWTriger sets TIOA (carry bit)
+ AT91C_BASE_TC0->TC_RC = 0; // set TIOA (carry bit) on overflow, return to zero
+ AT91C_BASE_TC0->TC_RA = 1; // clear carry bit on next clock cycle
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; // reset and re-enable timer
+
+ // synchronized startup procedure
+ while (AT91C_BASE_TC0->TC_CV > 0); // wait until TC0 returned to zero
+ while (AT91C_BASE_TC0->TC_CV < 2); // and has started (TC_CV > TC_RA, now TC1 is cleared)
+
+ // return to zero
+ AT91C_BASE_TC1->TC_CCR = AT91C_TC_SWTRG;
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_SWTRG;
+ while (AT91C_BASE_TC0->TC_CV > 0);
+}
- AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // timer disable
- AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_XC1; // from TC0
-
- AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
- AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
- AT91C_BASE_TCB->TCB_BCR = 1;
-
- // wait until timer becomes zero.
- while (AT91C_BASE_TC1->TC_CV > 0);
+
+uint32_t GetTicks(void) {
+ uint32_t hi, lo;
+
+ do {
+ hi = AT91C_BASE_TC1->TC_CV;
+ lo = AT91C_BASE_TC0->TC_CV;
+ } while(hi != AT91C_BASE_TC1->TC_CV);
+
+ return (hi << 16) | lo;
}
// if called with a high number, this will trigger the WDT...
void WaitTicks(uint32_t ticks){
if ( ticks == 0 ) return;
- ticks += GET_TICKS;
- while (GET_TICKS < ticks);
+ ticks += GetTicks();
+ while (GetTicks() < ticks);
}
// Wait / Spindelay in us (microseconds)
// 1us = 1.5ticks.
void WaitUS(uint16_t us){
- if ( us == 0 ) return;
- WaitTicks( (uint32_t)(us * 1.5) );
+ WaitTicks( (uint32_t)us * 3 / 2 ) ;
}
void WaitMS(uint16_t ms){
- if (ms == 0) return;
- WaitTicks( (uint32_t)(ms * 1500) );
+ WaitTicks( (uint32_t)ms * 1500 );
}
// Starts Clock and waits until its reset
void ResetTicks(void){
- AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
- while (AT91C_BASE_TC1->TC_CV > 0);
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
+ while (AT91C_BASE_TC0->TC_CV > 0);
}
projects / proxmark3-svn / blobdiff