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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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11
module01/ex02/main.c
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@@ -5,23 +5,24 @@
#include "timer.h"
#define PERIOD 1000
#define PRESCALE_VALUE 1024 // can be 1, 8, 64, 256, 1024
#define DUTY_CYCLE 10
// turns on led2 at 1Hz and duty cycle of 10%, not using PORTx, with empty infinite loop
int main() {
MODE_OUTPUT(LED2);
SET(TCCR1A, WGM11); // Table 16-4 : set timer in Fast PWM (Pulse With Modulation) mode with TOP = ICR1 (Mode 14)
SET(TCCR1A, WGM11); // Table 16-4 : set timer in Fast PWM (Pulse With Modulation) mode with TOP = ICR1 (Mode 14)
SET(TCCR1B, WGM12);
SET(TCCR1B, WGM13);
SET(TCCR1A, COM1A1); // Table 16-2 : non-inverting mode, the LED will be ON for DUTY_CYCLE% of the time (CLEAR OC1A on compare match, SET OC1A at BOTTOM)
SET(TCCR1A, COM1A1); // Table 16-2 : non-inverting mode, the LED will be ON for DUTY_CYCLE% of the time (CLEAR OC1A on compare match, SET OC1A at BOTTOM)
ICR1 = TIME_MS(PERIOD); // Table 16-4 : set the period (compare TOP value)
ICR1 = TIME_MS(PERIOD, PRESCALE_VALUE); // Table 16-4 : set the period (compare TOP value)
OCR1A = TIME_MS(PERCENT(DUTY_CYCLE, PERIOD)); // 16.9.3 : set the duty cycle to DUTY_CYCLE% of the time on channel A -> OC1A (alternate function of PORTB1, aka LED2) is cleared when TCNT1 (the counter value) equals OCR1A
OCR1A = TIME_MS(PERCENT(DUTY_CYCLE, PERIOD), PRESCALE_VALUE); // 16.9.3 : set the duty cycle to DUTY_CYCLE% of the time on channel A -> OC1A (alternate function of PORTB1, aka LED2) is cleared when TCNT1 (the counter value) equals OCR1A
TCCR1B |= (PRESCALE_SET(PRESCALE_VALUE)); // start the timer with the prescaler
TCCR1B |= (PRESCALE_SET(PRESCALE_VALUE)); // start the timer with the prescaler
while(1);
}

3
module01/ex02/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