diff --git a/armsrc/ticks.c b/armsrc/ticks.c index f084e3364..0a1796896 100644 --- a/armsrc/ticks.c +++ b/armsrc/ticks.c @@ -169,59 +169,70 @@ uint32_t RAMFUNC GetCountSspClk(void) { } // ------------------------------------------------------------------------- -// 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; - AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; - 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_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE; - 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); + // 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 | // 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); } + +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; +} + // Wait - Spindelay in ticks. // 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 * 3/2 ); + WaitTicks( (uint32_t)us * 3/2 ); } void WaitMS(uint16_t ms){ - if (ms == 0) return; 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); -} -void ResetTimer(AT91PS_TC timer){ - timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; - while(timer->TC_CV > 0) ; -} + // stop clock void StopTicks(void){ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; diff --git a/armsrc/ticks.h b/armsrc/ticks.h index 8ad4bc679..727a40d2f 100644 --- a/armsrc/ticks.h +++ b/armsrc/ticks.h @@ -19,7 +19,7 @@ #include "proxmark3.h" #ifndef GET_TICKS -# define GET_TICKS (uint32_t)((AT91C_BASE_TC1->TC_CV << 16) | AT91C_BASE_TC0->TC_CV) +#define GET_TICKS GetTicks() #endif void SpinDelay(int ms); @@ -32,17 +32,15 @@ void StartCountUS(void); uint32_t RAMFUNC GetCountUS(void); void ResetUSClock(void); void SpinDelayCountUs(uint32_t us); -//uint32_t RAMFUNC GetDeltaCountUS(void); void StartCountSspClk(); void ResetSspClk(void); uint32_t RAMFUNC GetCountSspClk(); -extern void StartTicks(void); -extern void WaitTicks(uint32_t ticks); -extern void WaitUS(uint16_t us); -extern void WaitMS(uint16_t ms); -extern void ResetTicks(); -extern void ResetTimer(AT91PS_TC timer); -extern void StopTicks(void); +void StartTicks(void); +uint32_t GetTicks(void); +void WaitTicks(uint32_t ticks); +void WaitUS(uint16_t us); +void WaitMS(uint16_t ms); +void StopTicks(void); #endif \ No newline at end of file