51 秒表

/*
*      秒表
*/
#include<reg52.h>
#define uchar unsigned char
uchar counter=0,tmp,second=0,minute=0, change = 1;
int led[]= {0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92, 0x82, 0xf8, 0x80, 0x90}; //数字0-9
int _led[]= {0x40, 0x79, 0x24, 0x30, 0x19, 0x12, 0x02, 0x78, 0x00, 0x10};
void main() {
    //设置TMOD寄存器
    TMOD=0X01;                            //设置TMOD寄存器
    TH0=(65536-5000)/256;               //装初值
    TL0=(65536-5000)%256;
    EA=1;        //开 中断
    ET0=1;
    TR0=1;
    while(1) {

        tmp=counter%4;
        switch(tmp) {
        case 0:
            P2 = 0x7f;
            P0 = led[second%10];
            break;
        case 1:
            P2 = 0xbf;
            P0 = led[second/10];
            break;
        case 2:
            P2 = 0xdf;
            P0 = _led[minute%10];
            break;
        case 3:
            P2 = 0xef;
            P0 = led[minute/10];
            break;

        }

    }
}
void zhongduan()interrupt 1 {
    TH0=(65536-5000)/256;               //装初值
    TL0=(65536-5000)%256;
    TF0=0;
    TR0=1;
    counter++;
    if(counter==200) {
        counter=0;
        second++;
        if(second==60) {
            second=0;
            minute++;
        }
    }
    change = 1;
}