Revision 27
beautifying
| lab2/i8254.h | ||
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| 10 | 10 |
*/ |
| 11 | 11 |
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| 12 | 12 |
#define TIMER_FREQ 1193182 /**< @brief clock frequency for timer in PC and AT */ |
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#define TIMER_MIN_FREQ 19 /**< @brief mininum frequency for timer */
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#define TIMER_MIN_FREQ (TIMER_FREQ/UINT16_MAX) + ((TIMER_FREQ % UINT16_MAX) ? 1 : 0) /**< @brief mininum frequency for timer */
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| 14 | 14 |
#define TIMER0_IRQ 0 /**< @brief Timer 0 IRQ line */ |
| 15 | 15 |
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| 16 | 16 |
/* I/O port addresses */ |
| lab2/lab2.c | ||
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| 43 | 43 |
extern int no_interrupts; |
| 44 | 44 |
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| 45 | 45 |
int(timer_test_int)(uint8_t time) {
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const uint32_t frequency = 60; // Frequency asummed at 60Hz |
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int ipc_status, r; |
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message msg; |
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uint8_t hook = 0; |
| 49 | 50 |
no_interrupts = 0; |
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int freq = 60; // better way to get the frequency of the timer??? |
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timer_subscribe_int(&hook); |
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int irq_set = BIT(hook); |
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while (time) {
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| ... | ... | |
| 61 | 61 |
case HARDWARE: /* hardware interrupt notification */ |
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if (msg.m_notify.interrupts & irq_set) { /* subscribed interrupt */
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timer_int_handler(); |
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if (!(no_interrupts % freq)) {
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if (!(no_interrupts % frequency)) {
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| 65 | 65 |
timer_print_elapsed_time(); |
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time--; |
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} |
| lab2/timer.c | ||
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| 8 | 8 |
int (timer_set_frequency)(uint8_t timer, uint32_t freq) {
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| 9 | 9 |
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// Frequencies out this range are not supported (by limitation of hardware) |
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if (freq > TIMER_FREQ || freq < TIMER_MIN_FREQ) return 1; |
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if (freq > TIMER_FREQ || freq < TIMER_MIN_FREQ) {
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printf("%s: Frequency out of range, must be between %d and %d.\n", __func__, TIMER_MIN_FREQ, TIMER_FREQ);
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return 1; |
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} |
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| 12 | 15 |
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| 13 | 16 |
uint8_t status = 0; |
| 14 | 17 |
if (timer_get_conf(timer, &status)) return 1; |
| ... | ... | |
| 48 | 51 |
return 0; |
| 49 | 52 |
} |
| 50 | 53 |
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int hook_id = 2;
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int hook_id; |
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int (timer_subscribe_int)(uint8_t *bit_no) {
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hook_id = 2; |
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if(bit_no == NULL) return 1; |
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*bit_no = hook_id; |
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if(sys_irqsetpolicy(TIMER0_IRQ, IRQ_REENABLE, &hook_id)) return 1; |
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return 0; |
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return sys_irqsetpolicy(TIMER0_IRQ, IRQ_REENABLE, &hook_id); |
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| 58 | 61 |
} |
| 59 | 62 |
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| 60 | 63 |
int (timer_unsubscribe_int)() {
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