62 lines
1.1 KiB
C
62 lines
1.1 KiB
C
#include <stdio.h>
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#define TIMER (*(uint64_t *)0x40004000)
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#define TIMER_CMP (*(uint64_t *)0x40004008)
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#define TRACE (*(unsigned char *)0x40000000)
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volatile int ticks = 0;
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int _write(int file, const char *ptr, int len) {
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int x;
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for (x = 0; x < len; x++) {
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TRACE = *ptr++;
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}
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return (len);
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}
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void timer_ISR() {
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uint32_t timer_value;
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ticks++;
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// timer_value = TIMER;
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// TIMER_CMP = timer_value + 1000;
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}
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void register_timer_isr() {
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asm volatile("la t0, TIMER_CMP_INT \n csrw mtvec, t0");
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asm volatile("li t1, 0x888 \n csrw mie, t1");
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}
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int main(void) {
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uint32_t timer_value;
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uint32_t start_time;
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register_timer_isr();
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start_time = TIMER;
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TIMER_CMP = start_time + 10000;
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printf("set timer to %ld ns\n", start_time + 10000);
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do {
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timer_value = TIMER;
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} while (timer_value < start_time + 200000);
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start_time = TIMER;
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TIMER_CMP = start_time + 10000;
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printf("set timer to %ld ns\n", start_time + 10000);
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do {
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timer_value = TIMER;
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} while (timer_value < start_time + 200000);
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printf("Timer: %ld ns\n", timer_value);
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printf("ticks: %ld\n", ticks);
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asm volatile ("ecall");
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return 0;
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}
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