X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/355c8b4a7df083c13d82963fb9d14548647e91b1..c41dd5f:/armsrc/util.c diff --git a/armsrc/util.c b/armsrc/util.c index a4f55879..4bff3a26 100644 --- a/armsrc/util.c +++ b/armsrc/util.c @@ -12,6 +12,7 @@ #include "util.h" #include "string.h" #include "apps.h" +#include "BigBuf.h" @@ -20,7 +21,7 @@ void print_result(char *name, uint8_t *buf, size_t len) { if ( len % 16 == 0 ) { for(; p-buf < len; p += 16) - Dbprintf("[%s:%d/%d] %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x", + Dbprintf("[%s:%d/%d] %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x", name, p-buf, len, @@ -29,12 +30,12 @@ void print_result(char *name, uint8_t *buf, size_t len) { } else { for(; p-buf < len; p += 8) - Dbprintf("[%s:%d/%d] %02x %02x %02x %02x %02x %02x %02x %02x", name, p-buf, len, p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]); + Dbprintf("[%s:%d/%d] %02x %02x %02x %02x %02x %02x %02x %02x", name, p-buf, len, p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]); } } size_t nbytes(size_t nbits) { - return (nbits/8)+((nbits%8)>0); + return (nbits >> 3)+((nbits % 8) > 0); } uint32_t SwapBits(uint32_t value, int nrbits) { @@ -67,22 +68,17 @@ uint64_t bytes_to_num(uint8_t* src, size_t len) // RotateLeft - Ultralight, Desfire void rol(uint8_t *data, const size_t len){ - uint8_t first = data[0]; - for (size_t i = 0; i < len-1; i++) { - data[i] = data[i+1]; - } - data[len-1] = first; + uint8_t first = data[0]; + for (size_t i = 0; i < len-1; i++) { + data[i] = data[i+1]; + } + 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); - } - data[len - 1] <<= 1; -} - -int32_t le24toh (uint8_t data[3]) -{ - return (data[2] << 16) | (data[1] << 8) | data[0]; + for (size_t n = 0; n < len - 1; n++) { + data[n] = (data[n] << 1) | (data[n+1] >> 7); + } + data[len - 1] <<= 1; } void LEDsoff() @@ -93,6 +89,22 @@ void LEDsoff() LED_D_OFF(); } +void LEDson() +{ + LED_A_ON(); + LED_B_ON(); + LED_C_ON(); + LED_D_ON(); +} + +void LEDsinvert() +{ + LED_A_INV(); + LED_B_INV(); + LED_C_INV(); + LED_D_INV(); +} + // LEDs: R(C) O(A) G(B) -- R(D) [1, 2, 4 and 8] void LED(int led, int ms) { @@ -267,15 +279,15 @@ void FormatVersionInformation(char *dst, int len, const char *prefix, void *vers dst[0] = 0; strncat(dst, prefix, len-1); if(v->magic != VERSION_INFORMATION_MAGIC) { - strncat(dst, "Missing/Invalid version information", len - strlen(dst) - 1); + strncat(dst, "Missing/Invalid version information\n", len - strlen(dst) - 1); return; } if(v->versionversion != 1) { - strncat(dst, "Version information not understood", len - strlen(dst) - 1); + strncat(dst, "Version information not understood\n", len - strlen(dst) - 1); return; } if(!v->present) { - strncat(dst, "Version information not available", len - strlen(dst) - 1); + strncat(dst, "Version information not available\n", len - strlen(dst) - 1); return; } @@ -288,27 +300,31 @@ void FormatVersionInformation(char *dst, int len, const char *prefix, void *vers strncat(dst, " ", len - strlen(dst) - 1); strncat(dst, v->buildtime, len - strlen(dst) - 1); + strncat(dst, "\n", len - strlen(dst) - 1); } + // ------------------------------------------------------------------------- // timer lib // ------------------------------------------------------------------------- // test procedure: // -// ti = GetTickCount(); -// SpinDelay(1000); -// ti = GetTickCount() - ti; -// Dbprintf("timer(1s): %d t=%d", ti, GetTickCount()); +// ti = GetTickCount(); +// SpinDelay(1000); +// ti = GetTickCount() - ti; +// Dbprintf("timer(1s): %d t=%d", ti, GetTickCount()); 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% } + /* * Get the current count. */ @@ -316,13 +332,14 @@ uint32_t RAMFUNC GetTickCount(){ return AT91C_BASE_RTTC->RTTC_RTVR;// was * 2; } + // ------------------------------------------------------------------------- -// microseconds timer +// microseconds timer // ------------------------------------------------------------------------- void StartCountUS() { AT91C_BASE_PMC->PMC_PCER |= (0x1 << 12) | (0x1 << 13) | (0x1 << 14); -// AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC1XC1S_TIOA0; +// AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC1XC1S_TIOA0; AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE; // fast clock @@ -332,19 +349,21 @@ void StartCountUS() AT91C_TC_ACPC_SET | AT91C_TC_ASWTRG_SET; AT91C_BASE_TC0->TC_RA = 1; AT91C_BASE_TC0->TC_RC = 0xBFFF + 1; // 0xC000 - - AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // timer disable + + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // timer disable AT91C_BASE_TC1->TC_CMR = AT91C_TC_CLKS_XC1; // from timer 0 - + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN; AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN; AT91C_BASE_TCB->TCB_BCR = 1; } + 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 * 2) / 3); //was /15) * 10); } + static uint32_t GlobalUsCounter = 0; uint32_t RAMFUNC GetDeltaCountUS(){ @@ -356,152 +375,202 @@ uint32_t RAMFUNC GetDeltaCountUS(){ // ------------------------------------------------------------------------- -// Timer for iso14443 commands. Uses ssp_clk from FPGA +// Timer for iso14443 commands. Uses ssp_clk from FPGA // ------------------------------------------------------------------------- void StartCountSspClk() { AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_TC0) | (1 << AT91C_ID_TC1) | (1 << AT91C_ID_TC2); // Enable Clock to all timers - AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_TIOA1 // XC0 Clock = TIOA1 - | AT91C_TCB_TC1XC1S_NONE // XC1 Clock = none - | AT91C_TCB_TC2XC2S_TIOA0; // XC2 Clock = TIOA0 + AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_TIOA1 // XC0 Clock = TIOA1 + | AT91C_TCB_TC1XC1S_NONE // XC1 Clock = none + | AT91C_TCB_TC2XC2S_TIOA0; // XC2 Clock = TIOA0 // configure TC1 to create a short pulse on TIOA1 when a rising edge on TIOB1 (= ssp_clk from FPGA) occurs: - AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // disable TC1 + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; // disable TC1 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_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_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 ... 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 = 0x02; // RC Compare value = 0x02 // use TC0 to count TIOA1 pulses - AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // disable TC0 - AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_XC0 // TC0 clock = XC0 clock = TIOA1 - | AT91C_TC_WAVE // Waveform Mode - | AT91C_TC_WAVESEL_UP // just count - | AT91C_TC_ACPA_CLEAR // Clear TIOA0 on RA Compare - | AT91C_TC_ACPC_SET; // Set TIOA0 on RC Compare - AT91C_BASE_TC0->TC_RA = 1; // RA Compare value = 1; pulse width to TC2 - AT91C_BASE_TC0->TC_RC = 0; // RC Compare value = 0; increment TC2 on overflow + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // disable TC0 + AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_XC0 // TC0 clock = XC0 clock = TIOA1 + | AT91C_TC_WAVE // Waveform Mode + | AT91C_TC_WAVESEL_UP // just count + | AT91C_TC_ACPA_CLEAR // Clear TIOA0 on RA Compare + | AT91C_TC_ACPC_SET; // Set TIOA0 on RC Compare + AT91C_BASE_TC0->TC_RA = 1; // RA Compare value = 1; pulse width to TC2 + AT91C_BASE_TC0->TC_RC = 0; // RC Compare value = 0; increment TC2 on overflow // use TC2 to count TIOA0 pulses (giving us a 32bit counter (TC0/TC2) clocked by ssp_clk) - AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKDIS; // disable TC2 - AT91C_BASE_TC2->TC_CMR = AT91C_TC_CLKS_XC2 // TC2 clock = XC2 clock = TIOA0 - | AT91C_TC_WAVE // Waveform Mode - | AT91C_TC_WAVESEL_UP; // just count - - AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN; // enable TC0 - AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN; // enable TC1 - AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN; // enable TC2 + AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKDIS; // disable TC2 + AT91C_BASE_TC2->TC_CMR = AT91C_TC_CLKS_XC2 // TC2 clock = XC2 clock = TIOA0 + | AT91C_TC_WAVE // Waveform Mode + | AT91C_TC_WAVESEL_UP; // just count + + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN; // enable TC0 + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN; // enable TC1 + AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN; // enable TC2 // - // synchronize the counter with the ssp_frame signal. Note: FPGA must be in any iso14446 mode, otherwise the frame signal 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 - while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high - // note: up to now two ssp_clk rising edges have passed since the rising edge of ssp_frame + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_FRAME); // wait for ssp_frame to be low + 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_CLK)); // wait for ssp_clk to go high; 1st ssp_clk after start of frame + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK); // wait for ssp_clk to go low; + while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high; 2nd ssp_clk after start of frame + if ((AT91C_BASE_SSC->SSC_RFMR & SSC_FRAME_MODE_BITS_IN_WORD(32)) == SSC_FRAME_MODE_BITS_IN_WORD(16)) { + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK); // wait for ssp_clk to go low; + while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high; 3rd ssp_clk after start of frame + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK); // wait for ssp_clk to go low; + while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high; 4th ssp_clk after start of frame + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK); // wait for ssp_clk to go low; + while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high; 5th ssp_clk after start of frame + while(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK); // wait for ssp_clk to go low; + while(!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_CLK)); // wait for ssp_clk to go high; 6th ssp_clk after start of frame + } // it is now safe to assert a sync signal. This sets all timers to 0 on next active clock edge - AT91C_BASE_TCB->TCB_BCR = 1; // assert Sync (set all timers to 0 on next active clock edge) - // at the next (3rd) ssp_clk rising edge, TC1 will be reset (and not generate a clock signal to TC0) - // at the next (4th) ssp_clk rising edge, TC0 (the low word of our counter) will be reset. From now on, + AT91C_BASE_TCB->TCB_BCR = 1; // assert Sync (set all timers to 0 on next active clock edge) + // at the next (3rd/7th) ssp_clk rising edge, TC1 will be reset (and not generate a clock signal to TC0) + // at the next (4th/8th) ssp_clk rising edge, TC0 (the low word of our counter) will be reset. From now on, // whenever the last three bits of our counter go 0, we can be sure to be in the middle of a frame transfer. - // (just started with the transfer of the 4th Bit). + // (just started with the transfer of the 3rd Bit). // The high word of the counter (TC2) will not reset until the low word (TC0) overflows. Therefore need to wait quite some time before // we can use the counter. - while (AT91C_BASE_TC0->TC_CV < 0xFFF0); + while (AT91C_BASE_TC0->TC_CV < 0xFFFF); + // Note: needs one more SSP_CLK cycle (1.18 us) until TC2 resets. Don't call GetCountSspClk() that soon. } -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; - } +void ResetSspClk(void) { + //enable clock of timer and software trigger + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + AT91C_BASE_TC2->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + while (AT91C_BASE_TC2->TC_CV > 0); } -void iso14a_clear_trace() { - clear_trace(); + +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; } -void iso14a_set_tracing(bool enable) { - set_tracing(enable); +// ------------------------------------------------------------------------- +// Timer for bitbanging, or LF stuff when you need a very precis timer +// 1us = 1.5ticks +// ------------------------------------------------------------------------- +void StartTicks(void){ + // 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 | // 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); } -void clear_trace() { - memset(trace, 0x44, TRACE_SIZE); - traceLen = 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; } -void set_tracing(bool enable) { - tracing = enable; + +// 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 += GetTicks(); + while (GetTicks() < ticks); } -/** - This is a function to store traces. All protocols can use this generic tracer-function. - The traces produced by calling this function can be fetched on the client-side - by 'hf list raw', alternatively 'hf list ' for protocol-specific - annotation of commands/responses. -**/ -bool RAMFUNC LogTrace(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_start, uint32_t timestamp_end, uint8_t *parity, bool readerToTag) -{ - if (!tracing) return FALSE; +// Wait / Spindelay in us (microseconds) +// 1us = 1.5ticks. +void WaitUS(uint16_t us){ + WaitTicks( (uint32_t)us * 3 / 2 ) ; +} - uint16_t num_paritybytes = (iLen-1)/8 + 1; // number of valid paritybytes in *parity - uint16_t duration = timestamp_end - timestamp_start; - // Return when trace is full - if (traceLen + sizeof(iLen) + sizeof(timestamp_start) + sizeof(duration) + num_paritybytes + iLen >= TRACE_SIZE) { - tracing = FALSE; // don't trace any more - return FALSE; - } +void WaitMS(uint16_t ms){ + WaitTicks( (uint32_t)ms * 1500 ); +} - // Traceformat: - // 32 bits timestamp (little endian) - // 16 bits duration (little endian) - // 16 bits data length (little endian, Highest Bit used as readerToTag flag) - // y Bytes data - // x Bytes parity (one byte per 8 bytes data) - - // timestamp (start) - trace[traceLen++] = ((timestamp_start >> 0) & 0xff); - trace[traceLen++] = ((timestamp_start >> 8) & 0xff); - trace[traceLen++] = ((timestamp_start >> 16) & 0xff); - trace[traceLen++] = ((timestamp_start >> 24) & 0xff); - - // duration - trace[traceLen++] = ((duration >> 0) & 0xff); - trace[traceLen++] = ((duration >> 8) & 0xff); - - // data length - trace[traceLen++] = ((iLen >> 0) & 0xff); - trace[traceLen++] = ((iLen >> 8) & 0xff); - - // readerToTag flag - if (!readerToTag) { - trace[traceLen - 1] |= 0x80; - } - // data bytes - if (btBytes != NULL && iLen != 0) { - memcpy(trace + traceLen, btBytes, iLen); - } - traceLen += iLen; +// Starts Clock and waits until its reset +void ResetTicks(void){ + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + while (AT91C_BASE_TC0->TC_CV > 0); +} + + +void ResetTimer(AT91PS_TC timer){ + timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG; + while(timer->TC_CV > 0) ; +} - // parity bytes - if (parity != NULL && iLen != 0) { - memcpy(trace + traceLen, parity, num_paritybytes); - } - traceLen += num_paritybytes; - return TRUE; +// stop clock +void StopTicks(void){ + AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; + AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS; } + +static uint64_t next_random = 1; + +/* Generates a (non-cryptographically secure) 32-bit random number. + * + * We don't have an implementation of the "rand" function or a clock to seed it + * with, so we just call GetTickCount the first time to seed ourselves. + */ +uint32_t prand() { + if (next_random == 1) { + next_random = GetTickCount(); + } + + next_random = next_random * 6364136223846793005 + 1; + return (uint32_t)(next_random >> 32) % 0xffffffff; +}