C51学习 之 A/D D/A

A/D电路图（ADC0804）

代码

#include <reg52.h>

sbit wela = P2^7;
sbit dula = P2^6;
sbit dawr = P3^6;
sbit dacs = P3^2;
sbit beep = P2^3;

void delay(unsignd int time)
{
    while(time--);
}

void init()
{
    dula = 0;
    wela = 0;
    dacs = 0;
    dawr = 0;
    P0 = 0;
}

int main()
{
    unsigned char var,flag;
    init();
    while (1) {
        if (flag == 0) {
            val += 5;
            P0 = val;
        }
        if (val == 255) {
            flag = 1;
            beep = 0;
            delay(10000);
            beep = 1;
        }
        delay(5000);
    } else {
        val -= 5;
        P0 = val;
        if (val == 0) {
            flag = 0;
            beep = 0;
            delay(10000);
            beep = 1;
            
        }
        delay(5000);
    }
}