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fix error in timer header in mod01

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hugo LAMY
2025-03-08 22:05:30 +01:00
parent dd13c6582c
commit d91524b14a
6 changed files with 21 additions and 21 deletions
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3
module01/ex01/main.c
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@@ -5,6 +5,7 @@
#include "timer.h"
#define PERIOD 500
#define PRESCALE_VALUE 1024 // can be 1, 8, 64, 256, 1024
// led turns on and off every PERIOD ms using CTC timer
int main() {
@@ -14,7 +15,7 @@ int main() {
TCCR1A |= (1 << COM1A0); // 14.3.1 : set Compare Output with COM1A0, it toggles OC1A on compare match (Table 16-1), OC1A is alternate function for PORTB1 (Table 14-3)
OCR1A = TIME_MS(PERIOD); // Table 16-4 : set CTC compare value on channel A, the counter is cleared to zero when the counter value (TCNT1) matches the OCR1A register
OCR1A = TIME_MS(PERIOD, PRESCALE_VALUE); // Table 16-4 : set CTC compare value on channel A, the counter is cleared to zero when the counter value (TCNT1) matches the OCR1A register
TCCR1B |= (PRESCALE_SET(PRESCALE_VALUE));

3
module01/ex01/timer.h
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@@ -1,7 +1,6 @@
#ifndef TIMER_H
#define TIMER_H
#define PRESCALE_VALUE 1024 // can be 1, 8, 64, 256, 1024
// table 16-5 : prescale sets
#define PRESCALE_SET(value) \
((value) == 1 ? (0<<CS12 | 0<<CS11 | 1<<CS10) : \
@@ -10,6 +9,6 @@
(value) == 256 ? (1<<CS12 | 0<<CS11 | 0<<CS10) : \
(value) == 1024? (1<<CS12 | 0<<CS11 | 1<<CS10) : \
(0<<CS12 | 0<<CS11 | 0<<CS10))
#define TIME_MS(ms) (((F_CPU / PRESCALE_VALUE) * ms) / 1000)
#define TIME_MS(ms, prescale_value) (((F_CPU / prescale_value) * ms) / 1000)
#endif // TIMER_H