Revision 18
Fix minor issue on set_frequency
| lab2/i8254.h | ||
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*/ |
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#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 TIMER0_IRQ 0 /**< @brief Timer 0 IRQ line */ |
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/* I/O port addresses */ |
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#define TIMER_0 0x40 /**< @brief Timer 0 count register */ |
| lab2/lab2.c | ||
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| 38 | 38 |
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int(timer_test_time_base)(uint8_t timer, uint32_t freq) {
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if (timer_set_frequency(timer, freq)) return 1; |
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return 0; |
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} |
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| lab2/timer.c | ||
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| 6 | 6 |
#include "i8254.h" |
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int (timer_set_frequency)(uint8_t timer, uint32_t freq) {
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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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uint8_t status = 0; |
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if (timer_get_conf(timer, &status)) return 1; |
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//Make command |
| ... | ... | |
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if (sys_outb(timer_port, lsb)) return 1; |
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if (sys_outb(timer_port, msb)) return 1; |
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//if (sys_outw(timer_port, counter_init)) return 1; |
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return 0; |
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} |
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