int main(void) {
io_init();
//adc_init();
init_interrupt();
TCCR1A = 0; // set entire TCCR1A register to 0
TCCR1B = 0;
TIMSK1 = (1 << TOIE1); // enable Timer1 overflow interrupt
TCCR1B |= (1 << CS12); // Set CS12 prescaler (100). Prescaler set to 256. 16 000 000 CPU speed / 256 = 62 500. Each bit is 1/62500 s = 16 us
interrupts_on();
while (1) {
;;
//lightAll();
//update7seg(0);
//bin_to_7seg(2, 0);
//set_output(OUT1, 1);
//set_output(OUT2, 1);
//set_output(OUT3, 1);
//set_output(OUT4, 1);
//set_output(OUT5, 1);
//set_output(OUT6, 1);
//set_output(OUT7, 1);
}
return 0;
}
static void
show_interrupt(void)
{
int err;
/* QUESTION: how did we get here if there was an assert above? */
/* now think about interrupts. you will need to understand how they
* work, and how they interact with get/setcontext for implementing
* preemptive threading. */
/* QUESTION: what does interrupts_on() do? see interrupt.c */
interrupts_on();
/* getcontext stores the process's signal mask */
err = getcontext(&mycontext);
assert(!err);
/* QUESTION: Are interrupts masked (i.e., disabled) in mycontext?
* HINT: use sigismember below. */
printf("interrupt is disabled = %d\n",
(unsigned int) sigismember(&mycontext.uc_sigmask, SIG_TYPE));
interrupts_off();
err = getcontext(&mycontext);
assert(!err);
/* QUESTION: which fields of mycontext changed as a result of the
* getcontext call above? */
printf("interrupt is disabled = %d\n",
(unsigned int) sigismember(&mycontext.uc_sigmask, SIG_TYPE));
}
int main(void) {
io_init();
timer0_init();
timer1_init(OFF);
interrupts_on();
while (1) {
}
return 0;
}
