]> cvs.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/util.c
fix 'hf iclass reader'
[proxmark3-svn] / armsrc / util.c
index 74fba94b764db748cf6a377ba23b96f5d06bc304..4bff3a26a5e03b6fb20745e009e90c8c9b075016 100644 (file)
@@ -21,7 +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,
@@ -30,7 +30,7 @@ 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]);
    }
 }
 
@@ -68,22 +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()
@@ -94,6 +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)
 {
@@ -268,15 +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;
        }
 
@@ -289,27 +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.
 */
@@ -317,13 +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
@@ -333,19 +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(){
@@ -357,75 +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);
+}
+
+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
+//  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);
+}
+
+
+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 += GetTicks();
+       while (GetTicks() < ticks);
+}
+
+
+// Wait / Spindelay in us (microseconds)
+// 1us = 1.5ticks.
+void WaitUS(uint16_t us){
+       WaitTicks( (uint32_t)us * 3 / 2 ) ;
+}
+
+
+void WaitMS(uint16_t ms){
+       WaitTicks( (uint32_t)ms * 1500 );
+}
+
+
+// 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) ;
+}
+
+
+// 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;
+}
Impressum, Datenschutz