/* *******************************************
 * File name: eint_test.c
 * Function:  AVR外部中断测试程序
 * Description: 通过外部中断控制输出端口电平
 * Author & Date: Joshua Chan, 2012/03/23
 * *******************************************/
#include 
#include 
#include 
#include 
#include 
#include "delay.h"
#include "eint_test.h"

/* 使能外部中断并设置触发方式
 * @intnum: 外部中断号, 取值范围 0~7
 * @isc: 触发方式(0:低电平, 1:电平变换, 2:下降沿, 3:上升沿)
 */
void int_init(unsigned char intnum, unsigned char isc)
{
    if (intnum<=3 && isc<=3) {
        EIMSK |= (1 << intnum);
        EICRA &= ~(3 << (intnum*2));
        EICRA |= (isc << (intnum*2));
    } else if ((intnum>=4 && intnum<=7) && isc<=3) {
        EIMSK |= (1 << intnum);
        EICRB &= ~(3 << (intnum*2));
        EICRB |= (isc << (intnum*2));
    }
}

/* 控制PE, PF端口输出
 * @num: 端口顺序号
 * @stat: 控制端口输出电平
 */
void ctl_output(unsigned char num, unsigned char stat)
{
    if ((num>=1 && num<=4) && (stat==1 || stat==0)) {
        DDRF |= (1 << (4-num));
        if (stat)
            PORTF |= (1 << (4-num));
        else
            PORTF &= ~(1 << (4-num));
    } else if ((num>=5 && num<=6) && (stat==1 || stat==0)) {
        DDRE |= (1 << (num-3));
        if (stat)
            PORTE |= (1 << (num-3));
        else
            PORTE &= ~(1 << (num-3));
    }
}

/* 定义中断处理函数 */
#pragma vector = INT3_vect
__interrupt void int3_isr(void)
{
    ctl_dcmotor(6, 0);          /* 启动直流电机6 */
    DELAY_MS(100);
    ctl_dcmotor(6, 1);          /* 停止直流电机6 */
}