二、51单片机实现0到99计时

• 51单片机实现0到99计时
• 51单片机设计0～99秒秒表_单片机程序设计
• 51单片机时钟如何倒计时
• 51单片机简易时钟的实现
• 51单片机-定时器

ps使用时钟频率，计时并不准确

单片机是普中STC89C516RD+

实现代码

#include <REGX52.H>

typedef unsigned int u16; // 对系统默认数据类型进行重定义
typedef unsigned char u8;

// 0~9数字
unsigned char numbers[] = {0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F};
sbit LSA                = P2 ^ 2;
sbit LSB                = P2 ^ 3;
sbit LSC                = P2 ^ 4;

void delay_10us(u16 ten_us)
{
    while (ten_us--)
        ;
}

void wz(u8 i) // 此显示位有8位
{
    switch (i) // 位选
    {
        case 0:
            LSC = 1;
            LSB = 1;
            LSA = 1;
            break;
        case 1:
            LSC = 1;
            LSB = 1;
            LSA = 0;
            break;
        case 2:
            LSC = 1;
            LSB = 0;
            LSA = 1;
            break;
        case 3:
            LSC = 1;
            LSB = 0;
            LSA = 0;
            break;
        case 4:
            LSC = 0;
            LSB = 1;
            LSA = 1;
            break;
        case 5:
            LSC = 0;
            LSB = 1;
            LSA = 0;
            break;
        case 6:
            LSC = 0;
            LSB = 0;
            LSA = 1;
            break;
        case 7:
            LSC = 0;
            LSB = 0;
            LSA = 0;
            break;
    }
}

void LED_draw(unsigned char position, number) // 每一帧进行绘制
{
    wz(position);         // LED的位置
    P0 = numbers[number]; // 显示数字 段选
    delay_10us(300);
    P0 = 0x00; // 消音
}

void main()
{
    u16 time = 0, currentNumber = 0;
    while (1) {
        if (currentNumber < 10)
            LED_draw(0, currentNumber % 10); // 个位
        else {
            LED_draw(0, currentNumber / 10); // 十位
            LED_draw(1, currentNumber % 10); // 个位
        }

        time++;
        if (time == 50) { // 用于控制间隔
            time = 0;
            currentNumber++;
            if (currentNumber == 100)
                currentNumber = 0; // reset number
        }
    }
}

效果