Re: [avr-gcc-list] light up and led

[Timothy Smith]

Joerg Wunsch wrote:

> Timothy Smith <address@hidden> wrote:
>
>  
>
> >    while (1) {
> >        PORTA &= !(1<<PA0);
> >    
>
> ! is the Boolean negation.  You want bitwise negation, operator ~.
>
>  
ok i made it turn on. now i've attempted to make it blink,
unsuccessfully. the light just stays off now.
also, is there a more elegant way of doing time delays? i've seen many
examples, most of wish look rather rough for such a simple requirment

#include <avr/io.h>

void wait (void)
{
   asm volatile ("nop"::);
}

int
main(void){
   unsigned char j;
   unsigned char i;
   DDRA |= 1<<PA0;
   while (1) {
       for (i=0; i<20000; i++) wait();
       PORTA |= 1<<PA0;
       for (j=0; j<20000; j++) wait();
       PORTA &= ~(1<<PA0);
   };
}

on furthur inspection is appears my for loops are the problem.