独立按键和一位闪烁的数码管

本文主要内容：使用Proteus设计单片机外围电路图并模拟最终效果。用动态显示的方法点亮四位极数码管，有一位需要以固定频率闪烁。另有四个按键分别为KS0~KS3，按下KS1将使闪烁的数位循环右移，按下K2将使闪烁数位的数字加一，达到0x0F时归零。

Proteus设计图：

 说明：数码管位选信号输出时将被取反；按键按下时引脚为“0”；80C51单片机频率是12MHz；数码管共阴极（CC）；设计图只为验证逻辑功能，无实际考量。

 C语言代码：

#include 

unsigned char code SegCode[16] = {
　　0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,
　　0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71
};
unsigned char Numbers[4];

#define BlinkON 1
#define BlinkOFF 0
unsigned char BlinkStatus, BlinkGrid;

void BtnRoutine_K0() {}
void BtnRoutine_K1()
{
    BlinkGrid += 1;
    BlinkGrid &= 0x03;
}
void BtnRoutine_K2()
{
    Numbers[BlinkGrid] += 1;
    Numbers[BlinkGrid] &= 0x0F;
}
void BtnRoutine_K3() {}
void (*KeyRoutines[4])(void) = {
    BtnRoutine_K0,
    BtnRoutine_K1,
    BtnRoutine_K2,
    BtnRoutine_K3
};
int main()
{
    unsigned char i, j, KeyBitMap, LastKeyBitMap = 0;

    for (i = 0; i < 4; i++)
        Numbers[i] = 0;
    BlinkStatus = BlinkOFF;
    BlinkGrid = 0;
    P0 = 0;
    P2 = 0xF0;

    TMOD = 1;
    TH0 = 0xD8;
    TL0 = 0xF0;
    ET0 = 1;
    TR0 = 1;
    EA = 1;

    while (1)
    {
        P2 |= 0xF0;
        KeyBitMap = (~P2) >> 4;
        for (i = 0; i < 4; i++)
        {
            j = 0x01 << i;
            if (KeyBitMap & j){
                if (!(LastKeyBitMap & j))
                    LastKeyBitMap |= j;
            }else if (LastKeyBitMap & j){
                KeyRoutines[i]();
                LastKeyBitMap &= ~j;
            }
        }
    }
}
void Timer0_Routine() interrupt 1
{
    static unsigned char Cnt10ms = 0;
    static unsigned char WhichLed = 0;
    TH0 = 0xD8;
    TL0 = 0xF0;
    if (++Cnt10ms == 30)
    {
        BlinkStatus = ~BlinkStatus;
        Cnt10ms = 0;
    }
    if (WhichLed == BlinkGrid && BlinkStatus == BlinkOFF)
    {
        P0 = 0;
        P2 = 0xF0 | (0x01 << BlinkGrid);
        P0 = 0;
    }
    else
    {
        P0 = 0;
        P2 = 0xF0 | (0x01 << WhichLed);
        P0 = SegCode[Numbers[WhichLed]];
    }
    WhichLed = (WhichLed + 1) & 0x03;
}