22 lines
1006 B
C
22 lines
1006 B
C
#include "header.h"
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// Set up Timer1 in CTC mode to trigger every 20ms
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// With 16MHz clock and prescaler of 64, and OCR1A = 49999:
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// 16000000/64/50000 = 20ms period
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#define T1B_PRESCALE_VALUE 64
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void timer_1B_init() {
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TCCR1A = 0; // 16.11.1 : Normal operation, OC1A/OC1B disconnected
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TCCR1B = CTC_TOP_OCR1A_IN_TCCR1B; // 16.11.2 : CTC mode top OCR1A
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TCCR1B |= T1_PRESCALE_SET(T1B_PRESCALE_VALUE); // 16.11.2 : prescaler
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OCR1A = TIME_MS(20, T1B_PRESCALE_VALUE); // 16.11.5 : Compare match value for register A
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// OCR1B = ; // 16.11.6 : Compare match value for register B, since not defined, should default to 0
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TIMSK1 = (1 << OCIE1B); // 16.11.8 : Enable Timer1 Compare B Match Interrupt
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// ADCSRA |= (1 << ADSC); // 24.9.2 : start first conversion
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}
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ISR(TIMER1_COMPB_vect) {
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// Empty ISR to ensure proper flag clearing or something like that (p145 : "OCF1B is automatically cleared when the Output Compare Match B Interrupt Vector is executed")
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} |