Question

单片机的·问题·

P1口做输出口，控制八只灯，已知P1口输出低电平时灯被点亮。某一按键连接P3.2管脚，利用手控单脉冲下降沿信号作为外部中断信号，控制八只灯按P1.0->P1.1->....>P1.7->P1.0...规律循环点亮（即每次按键灯依次移一位）。试编程实现。

Answer 1

#include<reg51.h>
#include<intrins.h>
#define uchar unsigned char
uchar num;
uchar led[]={0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f,0xbf,0xdf,0xef,0xf7,0xfb,0xfd};
void ext0() interrupt 0
{
    P1=led[num];
    num++;
    num%=14;
}
main()
{
    EX0=1;
    IT0=1;
    EA=1;
    while(1);
}