单片机 之基于中断带消隐的数码管动态显示示例

#include <reg52.h>

sbit ADDR0 = P1^0;
sbit ADDR1 = P1^1;
sbit ADDR2 = P1^2;
sbit ADDR3 = P1^3;
sbit ENLED = P1^4;

unsigned char code LedChar[] = {  //数码管显示字符转换表
    0xC0, 0xF9, 0xA4, 0xB0, 0x99, 0x92, 0x82, 0xF8,
    0x80, 0x90, 0x88, 0x83, 0xC6, 0xA1, 0x86, 0x8E
};
unsigned char LedBuff[6] = {  //数码管显示缓冲区，初值0xFF确保启动时都不亮
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
};
unsigned char i = 0;   //动态扫描的索引
unsigned int cnt = 0;  //记录T0中断次数



void main()
{
    unsigned long sec = 0;  //记录经过的秒数

    EA = 1;       //使能总中断
    ENLED = 0;    //使能U3，选择控制数码管
    ADDR3 = 1;    //因为需要动态改变ADDR0-2的值，所以不需要再初始化了
    TMOD = 0x01;  //设置T0为模式1
    TH0  = 0xFC;  //为T0赋初值0xFC67，定时1ms
    TL0  = 0x67;
    ET0  = 1;     //使能T0中断
    TR0  = 1;     //启动T0
    
    while (1)
    {
        if (cnt >= 1000)  //判断T0溢出是否达到1000次
        {
            cnt = 0;      //达到1000次后计数值清零
            sec++;        //秒计数自加1
            //以下代码将sec按十进制位从低到高依次提取并转为数码管显示字符
            LedBuff[0] = LedChar[sec%10];
            LedBuff[1] = LedChar[sec/10%10];
            LedBuff[2] = LedChar[sec/100%10];
            LedBuff[3] = LedChar[sec/1000%10];
            LedBuff[4] = LedChar[sec/10000%10];
            LedBuff[5] = LedChar[sec/100000%10];
        }
    }
}
/* 定时器0中断服务函数 */
void InterruptTimer0() interrupt 1    

//1-计算公式 x*8+3=中断向量 转10进制值 0x000B =11   x=1 即 TO中断号 1#

{
    TH0 = 0xFC;  //重新加载初值
    TL0 = 0x67;
    cnt++;       //中断次数计数值加1
    //以下代码完成数码管动态扫描刷新
    P0 = 0xFF;   //显示消隐
    switch (i)
    {
        case 0: ADDR2=0; ADDR1=0; ADDR0=0; i++; P0=LedBuff[0]; break;
        case 1: ADDR2=0; ADDR1=0; ADDR0=1; i++; P0=LedBuff[1]; break;
        case 2: ADDR2=0; ADDR1=1; ADDR0=0; i++; P0=LedBuff[2]; break;
        case 3: ADDR2=0; ADDR1=1; ADDR0=1; i++; P0=LedBuff[3]; break;
        case 4: ADDR2=1; ADDR1=0; ADDR0=0; i++; P0=LedBuff[4]; break;
        case 5: ADDR2=1; ADDR1=0; ADDR0=1; i=0; P0=LedBuff[5]; break;
        default: break;
    }
}