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/* beep.c */ #include <avr/io.h> #include "common.h" #define DDR_BEEP DDRB #define PORT_BEEP PORTB #define PIN_BEEP 1 void beep_on(void) { TIMSK1 = 0; TCCR1A = (1<<COM1A0); TCCR1B = (1<<CS10) | (1<<WGM12); /* clkIO / 1, CTC mode */ DDR_BEEP |= (1<<PIN_BEEP); OCR1A = 1000; } void beep_off(void) { DDR_BEEP &= ~(1<<PIN_BEEP); }