1 //-----------------------------------------------------------------------------
2 // Jonathan Westhues, Sept 2005
5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
6 // at your option, any later version. See the LICENSE.txt file for the text of
8 //-----------------------------------------------------------------------------
9 // Timers, Clocks functions used in LF or Legic where you would need detailed time.
10 //-----------------------------------------------------------------------------
14 // attempt at high resolution microsecond timer
15 // beware: timer counts in 21.3uS increments (1024/48Mhz)
16 void SpinDelayUs(int us
) {
17 int ticks
= (48 * us
) >> 10;
19 // Borrow a PWM unit for my real-time clock
20 AT91C_BASE_PWMC
->PWMC_ENA
= PWM_CHANNEL(0);
22 // 48 MHz / 1024 gives 46.875 kHz
23 AT91C_BASE_PWMC_CH0
->PWMC_CMR
= PWM_CH_MODE_PRESCALER(10);
24 AT91C_BASE_PWMC_CH0
->PWMC_CDTYR
= 0;
25 AT91C_BASE_PWMC_CH0
->PWMC_CPRDR
= 0xffff;
27 uint16_t start
= AT91C_BASE_PWMC_CH0
->PWMC_CCNTR
;
30 uint16_t now
= AT91C_BASE_PWMC_CH0
->PWMC_CCNTR
;
31 if (now
== (uint16_t)(start
+ ticks
))
38 void SpinDelay(int ms
) {
39 // convert to uS and call microsecond delay function
42 // -------------------------------------------------------------------------
44 // -------------------------------------------------------------------------
47 // ti = GetTickCount();
49 // ti = GetTickCount() - ti;
50 // Dbprintf("timer(1s): %d t=%d", ti, GetTickCount());
51 void StartTickCount(void) {
52 // This timer is based on the slow clock. The slow clock frequency is between 22kHz and 40kHz.
53 // We can determine the actual slow clock frequency by looking at the Main Clock Frequency Register.
54 uint16_t mainf
= AT91C_BASE_PMC
->PMC_MCFR
& 0xffff; // = 16 * main clock frequency (16MHz) / slow clock frequency
55 // set RealTimeCounter divider to count at 1kHz:
56 AT91C_BASE_RTTC
->RTTC_RTMR
= AT91C_RTTC_RTTRST
| ((256000 + (mainf
/2)) / mainf
);
57 // note: worst case precision is approx 2.5%
61 * Get the current count.
63 uint32_t RAMFUNC
GetTickCount(void){
64 return AT91C_BASE_RTTC
->RTTC_RTVR
;// was * 2;
67 // -------------------------------------------------------------------------
69 // -------------------------------------------------------------------------
70 void StartCountUS(void) {
71 AT91C_BASE_PMC
->PMC_PCER
|= (1 << 12) | (1 << 13) | (1 << 14);
72 AT91C_BASE_TCB
->TCB_BMR
= AT91C_TCB_TC0XC0S_NONE
| AT91C_TCB_TC1XC1S_TIOA0
| AT91C_TCB_TC2XC2S_NONE
;
76 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKDIS
; // timer disable
77 AT91C_BASE_TC0
->TC_CMR
= AT91C_TC_CLKS_TIMER_DIV3_CLOCK
| // MCK(48MHz) / 32
78 AT91C_TC_WAVE
| AT91C_TC_WAVESEL_UP_AUTO
| AT91C_TC_ACPA_CLEAR
|
79 AT91C_TC_ACPC_SET
| AT91C_TC_ASWTRG_SET
;
80 AT91C_BASE_TC0
->TC_RA
= 1;
81 AT91C_BASE_TC0
->TC_RC
= 0xBFFF + 1; // 0xC000
83 AT91C_BASE_TC1
->TC_CCR
= AT91C_TC_CLKDIS
; // timer disable
84 AT91C_BASE_TC1
->TC_CMR
= AT91C_TC_CLKS_XC1
; // from timer 0
86 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
87 AT91C_BASE_TC1
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
88 AT91C_BASE_TCB
->TCB_BCR
= 1;
90 while (AT91C_BASE_TC1
->TC_CV
>= 1);
93 uint32_t RAMFUNC
GetCountUS(void){
94 //return (AT91C_BASE_TC1->TC_CV * 0x8000) + ((AT91C_BASE_TC0->TC_CV / 15) * 10);
95 // By suggestion from PwPiwi, http://www.proxmark.org/forum/viewtopic.php?pid=17548#p17548
96 return (AT91C_BASE_TC1
->TC_CV
* 0x8000) + ((AT91C_BASE_TC0
->TC_CV
* 2) / 3);
100 // -------------------------------------------------------------------------
101 // Timer for iso14443 commands. Uses ssp_clk from FPGA
102 // -------------------------------------------------------------------------
103 void StartCountSspClk(void) {
104 AT91C_BASE_PMC
->PMC_PCER
= (1 << AT91C_ID_TC0
) | (1 << AT91C_ID_TC1
) | (1 << AT91C_ID_TC2
); // Enable Clock to all timers
105 AT91C_BASE_TCB
->TCB_BMR
= AT91C_TCB_TC0XC0S_TIOA1
// XC0 Clock = TIOA1
106 | AT91C_TCB_TC1XC1S_NONE
// XC1 Clock = none
107 | AT91C_TCB_TC2XC2S_TIOA0
; // XC2 Clock = TIOA0
109 // configure TC1 to create a short pulse on TIOA1 when a rising edge on TIOB1 (= ssp_clk from FPGA) occurs:
110 AT91C_BASE_TC1
->TC_CCR
= AT91C_TC_CLKDIS
; // disable TC1
111 AT91C_BASE_TC1
->TC_CMR
= AT91C_TC_CLKS_TIMER_DIV1_CLOCK
// TC1 Clock = MCK(48MHz)/2 = 24MHz
112 | AT91C_TC_CPCSTOP
// Stop clock on RC compare
113 | AT91C_TC_EEVTEDG_RISING
// Trigger on rising edge of Event
114 | AT91C_TC_EEVT_TIOB
// Event-Source: TIOB1 (= ssp_clk from FPGA = 13,56MHz/16)
115 | AT91C_TC_ENETRG
// Enable external trigger event
116 | AT91C_TC_WAVESEL_UP
// Upmode without automatic trigger on RC compare
117 | AT91C_TC_WAVE
// Waveform Mode
118 | AT91C_TC_AEEVT_SET
// Set TIOA1 on external event
119 | AT91C_TC_ACPC_CLEAR
; // Clear TIOA1 on RC Compare
120 AT91C_BASE_TC1
->TC_RC
= 0x04; // RC Compare value = 0x04
122 // use TC0 to count TIOA1 pulses
123 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKDIS
; // disable TC0
124 AT91C_BASE_TC0
->TC_CMR
= AT91C_TC_CLKS_XC0
// TC0 clock = XC0 clock = TIOA1
125 | AT91C_TC_WAVE
// Waveform Mode
126 | AT91C_TC_WAVESEL_UP
// just count
127 | AT91C_TC_ACPA_CLEAR
// Clear TIOA0 on RA Compare
128 | AT91C_TC_ACPC_SET
; // Set TIOA0 on RC Compare
129 AT91C_BASE_TC0
->TC_RA
= 1; // RA Compare value = 1; pulse width to TC2
130 AT91C_BASE_TC0
->TC_RC
= 0; // RC Compare value = 0; increment TC2 on overflow
132 // use TC2 to count TIOA0 pulses (giving us a 32bit counter (TC0/TC2) clocked by ssp_clk)
133 AT91C_BASE_TC2
->TC_CCR
= AT91C_TC_CLKDIS
; // disable TC2
134 AT91C_BASE_TC2
->TC_CMR
= AT91C_TC_CLKS_XC2
// TC2 clock = XC2 clock = TIOA0
135 | AT91C_TC_WAVE
// Waveform Mode
136 | AT91C_TC_WAVESEL_UP
; // just count
138 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
; // enable and reset TC0
139 AT91C_BASE_TC1
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
; // enable and reset TC1
140 AT91C_BASE_TC2
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
; // enable and reset TC2
142 // synchronize the counter with the ssp_frame signal.
143 // Note: FPGA must be in any iso14443 mode, otherwise the frame signal would not be present
144 while(!(AT91C_BASE_PIOA
->PIO_PDSR
& GPIO_SSC_FRAME
)); // wait for ssp_frame to go high (start of frame)
145 while(AT91C_BASE_PIOA
->PIO_PDSR
& GPIO_SSC_FRAME
); // wait for ssp_frame to be low
146 while(!(AT91C_BASE_PIOA
->PIO_PDSR
& GPIO_SSC_CLK
)); // wait for ssp_clk to go high
148 // note: up to now two ssp_clk rising edges have passed since the rising edge of ssp_frame
149 // it is now safe to assert a sync signal. This sets all timers to 0 on next active clock edge
150 AT91C_BASE_TCB
->TCB_BCR
= 1; // assert Sync (set all timers to 0 on next active clock edge)
151 // at the next (3rd) ssp_clk rising edge, TC1 will be reset (and not generate a clock signal to TC0)
152 // at the next (4th) ssp_clk rising edge, TC0 (the low word of our counter) will be reset. From now on,
153 // whenever the last three bits of our counter go 0, we can be sure to be in the middle of a frame transfer.
154 // (just started with the transfer of the 4th Bit).
156 // The high word of the counter (TC2) will not reset until the low word (TC0) overflows.
157 // Therefore need to wait quite some time before we can use the counter.
158 while (AT91C_BASE_TC2
->TC_CV
>= 1);
160 void ResetSspClk(void) {
161 //enable clock of timer and software trigger
162 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
163 AT91C_BASE_TC1
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
164 AT91C_BASE_TC2
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
165 while (AT91C_BASE_TC2
->TC_CV
>= 1);
168 uint32_t RAMFUNC
GetCountSspClk(void) {
169 uint32_t tmp_count
= (AT91C_BASE_TC2
->TC_CV
<< 16) | AT91C_BASE_TC0
->TC_CV
;
170 if ((tmp_count
& 0x0000ffff) == 0) //small chance that we may have missed an increment in TC2
171 return (AT91C_BASE_TC2
->TC_CV
<< 16);
176 // -------------------------------------------------------------------------
177 // Timer for bitbanging, or LF stuff when you need a very precis timer
179 // -------------------------------------------------------------------------
180 void StartTicks(void){
181 //initialization of the timer
182 AT91C_BASE_PMC
->PMC_PCER
|= (1 << 12) | (1 << 13) | (1 << 14);
183 AT91C_BASE_TCB
->TCB_BMR
= AT91C_TCB_TC0XC0S_NONE
| AT91C_TCB_TC1XC1S_TIOA0
| AT91C_TCB_TC2XC2S_NONE
;
184 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKDIS
;
185 AT91C_BASE_TC0
->TC_CMR
= AT91C_TC_CLKS_TIMER_DIV3_CLOCK
; //clock at 48/32 MHz
186 AT91C_BASE_TC0
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
187 AT91C_BASE_TCB
->TCB_BCR
= 1;
188 // wait until timer becomes zero.
189 while (AT91C_BASE_TC0
->TC_CV
> 1);
191 // Wait - Spindelay in ticks.
192 // if called with a high number, this will trigger the WDT...
193 void WaitTicks(uint32_t ticks
){
194 if ( ticks
== 0 ) return;
196 while (GET_TICKS
< ticks
);
198 // Wait / Spindelay in us (microseconds)
200 void WaitUS(uint16_t us
){
201 if ( us
== 0 ) return;
202 WaitTicks( (uint32_t)(us
* 1.5) );
204 void WaitMS(uint16_t ms
){
206 WaitTicks( (uint32_t)(ms
* 1500) );
208 // Starts Clock and waits until its reset
210 ResetTimer(AT91C_BASE_TC0
);
212 void ResetTimer(AT91PS_TC timer
){
213 timer
->TC_CCR
= AT91C_TC_CLKEN
| AT91C_TC_SWTRG
;
214 while(timer
->TC_CV
>= 1) ;