}
uint32_t SwapBits(uint32_t value, int nrbits) {
- int i;
uint32_t newvalue = 0;
- for(i = 0; i < nrbits; i++) {
+ for(int i = 0; i < nrbits; i++) {
newvalue ^= ((value >> i) & 1) << (nrbits - 1 - i);
}
return newvalue;
}
data[len-1] = first;
}
+
void lsl (uint8_t *data, size_t len) {
for (size_t n = 0; n < len - 1; n++) {
data[n] = (data[n] << 1) | (data[n+1] >> 7);
void StartTickCount()
{
-// must be 0x40, but on my cpu - included divider is optimal
-// 0x20 - 1 ms / bit
-// 0x40 - 2 ms / bit
-
- AT91C_BASE_RTTC->RTTC_RTMR = AT91C_RTTC_RTTRST + 0x001D; // was 0x003B
+ // This timer is based on the slow clock. The slow clock frequency is between 22kHz and 40kHz.
+ // We can determine the actual slow clock frequency by looking at the Main Clock Frequency Register.
+ uint16_t mainf = AT91C_BASE_PMC->PMC_MCFR & 0xffff; // = 16 * main clock frequency (16MHz) / slow clock frequency
+ // set RealTimeCounter divider to count at 1kHz:
+ AT91C_BASE_RTTC->RTTC_RTMR = AT91C_RTTC_RTTRST | ((256000 + (mainf/2)) / mainf);
+ // note: worst case precision is approx 2.5%
}
/*
// fast clock
AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK | // MCK(48MHz)/32 -- tick=1.5mks
- AT91C_TC_WAVE | AT91C_TC_WAVESEL_UP_AUTO | AT91C_TC_ACPA_CLEAR |
- AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET;
+ 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 = 0xBFFF + 1; // 0xC000
}
uint32_t RAMFUNC GetCountUS(){
- return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV / 15) * 10);
+ //return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV / 15) * 10);
+ // By suggestion from PwPiwi, http://www.proxmark.org/forum/viewtopic.php?pid=17548#p17548
+ return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV * 2) / 3);
}
static uint32_t GlobalUsCounter = 0;
while (AT91C_BASE_TC0->TC_CV < 0xFFF0);
}
-
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
+ uint32_t 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;
- }
+ return tmp_count;
}