iar9-2.c

手把手教你学AVR单片机C程序设计实验程序

#include <iom16.h>
#include<intrinsics.h>
#define uchar unsigned char	
#define uint unsigned int
__flash uchar SEG7[10]={0x3f,0x06,0x5b, 
		0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
__flash uchar ACT[8]={0xfe,0xfd,0xfb,0xf7, 
0xef,0xdf,0xbf,0x7f};
uchar i;	

void port_init(void)
{
 PORTA = 0x00;
 DDRA  = 0xFF;
 PORTB = 0xFF;
 DDRB  = 0x00;
 PORTC = 0xFF; 
 DDRC  = 0xFF;
 PORTD = 0xFF;
 DDRD  = 0x00;
}

//TIMER0 initialize - prescale:64
// WGM: Normal
// desired value: 1mSec
// actual value:  1.000mSec (0.0%)
void timer0_init(void)
{
 TCCR0 = 0x00; //stop
 TCNT0 = 0x83; //set count
 OCR0  = 0x7D;  //set compare
 TCCR0 = 0x03; //start timer
}

//call this routine to initialize all peripherals
void init_devices(void)
{
 SREG=0x00;
 port_init();
 timer0_init();

 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x01; //timer interrupt sources
 SREG=0x80;
}

void main(void) 
 {			
 init_devices(); 
 while(1);
 }

#pragma vector=TIMER0_OVF_vect
__interrupt void timer0_ovf_isr(void)
{
 TCNT0 = 0x83; //reload counter value
 if(++i>7)i=0;
 PORTA=SEG7[i];
 PORTC=ACT[i];
}