51单片机AD模块PCF8591 1路AD采样+数码管显示+Proteus仿真

51单片机AD模块PCF8591 1路AD采样+数码管显示+Proteus仿真

在这里插入图片描述

实例代码

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#include<reg51.h>
#include<intrins.h>

typedef unsigned char uint8;
typedef unsigned int uint16;
typedef unsigned long uint32;

sbit ADDRC = P1^0;
sbit ADDRB = P1^1;
sbit ADDRA = P1^2;//控制138译码器的三个引脚

sbit I2C_SDA = P2^1;
sbit I2C_SCL = P2^0;//I2C通信的两个引脚

bit flag_300ms = 0;//300ms时间标志位
uint8 T0RH = 0;//定时器高8位初值
uint8 T0RL = 0;//定时器低8位初值
uint8 AD_value = 0;//AD值
uint8 code led_char[] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,
                                                 0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};//LED段码

void config\_timer0(uint8 ms);
uint8 get\_ADC\_vaule(uint8 chn);

void main()
{
        config\_timer0(1);//初始化通用定时器0，定时1ms
        while(1)
        {
                if(flag_300ms == 1)        //判断300ms时间是否到了
                {
                        flag_300ms = 0;//清除标志位
                        AD_value = get\_ADC\_vaule(0);//读取通道0的AD值
                }                        
        }
}

void I2C\_delay()//I2C延时函数
{
        \_nop\_();
        \_nop\_();
        \_nop\_();
        \_nop\_();
}

void I2C\_start()//I2C起始信号
{
        I2C_SDA = 1;
        I2C_SCL = 1;
        I2C\_delay();
        I2C_SDA = 0;
        I2C\_delay();
        I2C_SCL = 0;
        I2C\_delay();
}

void I2C\_stop()//I2C停止信号
{
        I2C_SDA = 0;
        I2C_SCL = 0;
        I2C\_delay();
        I2C_SCL = 1;
        I2C\_delay();
        I2C_SDA = 1;
        I2C\_delay();
}

bit I2C\_write(uint8 dat)//I2C写一个字节
{
        bit ack = 0;
        uint8 mask = 0;
        for(mask=0x80;mask!=0;mask>>=1)
        {
                if((mask&dat) == 0)
                        I2C_SDA = 0;
                else
                        I2C_SDA = 1;
                I2C\_delay();
                I2C_SCL = 1;
                I2C\_delay();
                I2C_SCL = 0;
                I2C\_delay();
        }
        I2C_SDA = 1;
        I2C\_delay();
        I2C_SCL = 1;
        I2C\_delay();
        ack = I2C_SDA;
        I2C\_delay();
        I2C_SCL = 0;
        I2C\_delay();
        
        return (~ack);        
}

uint8 I2C\_read\_ACK()//I2C读一个字节，并发送应答位
{
        uint8 dat = 0;
        uint8 mask = 0;
        I2C_SDA = 1;
        for(mask=0x80;mask!=0;mask>>=1)
        {
                if(I2C_SDA == 0)
                        dat = dat & (~mask);
                else
                        dat = dat | mask;
                I2C\_delay();
                I2C_SCL = 1;
                I2C\_delay();
                I2C_SCL = 0;
                I2C\_delay();
        }
        I2C_SDA = 0;
        I2C\_delay();
        I2C_SCL = 1;
        I2C\_delay();
        I2C_SCL = 0;
        I2C\_delay();

        return dat;
}

uint8 I2C\_read\_NACK()//I2C读一个字节，并发送非应答位
{
        uint8 dat = 0;
        uint8 mask = 0;
        I2C_SDA = 1;
        for(mask=0x80;mask!=0;mask>>=1)
        {
                if(I2C_SDA == 0)
                        dat = dat & (~mask);
                else
                        dat = dat | mask;
                I2C\_delay();
                I2C_SCL = 1;
                I2C\_delay();
                I2C_SCL = 0;
                I2C\_delay();
        }
        I2C_SDA = 1;
        I2C\_delay();
        I2C_SCL = 1;
        I2C\_delay();
        I2C_SCL = 0;
        I2C\_delay();

        return dat;
}

uint8 get\_ADC\_vaule(uint8 chn)//获取AD值
{
        uint8 value = 0;
        I2C\_start();//I2C起始信号
        if(!I2C\_write(0X90))//写入PCF8591地址及读写选择位为写
        {
                I2C\_stop();
                return 0;
        }
// I2C\_write(0X40 | chn);//写入PCF8591通道0
        I2C\_write(0x00 | chn);//写入PCF8591通道0
        I2C\_start();//I2C起始信号
        I2C\_write(0x48<<1 | 0x01);
        I2C\_read\_ACK();//提供转换所需的时钟信号
        value = I2C\_read\_NACK();//读取上一次转换的结果
        I2C\_stop();//I2C结束信号

        return value;
}

void config\_timer0(uint8 ms)//配置定时器0的通用函数
{
        uint32 temp =0 ;
        temp = 11059200/12;
        temp = (temp \* ms)/1000;
        temp = 65536 - (temp + 12);
        T0RH = (uint8)(temp >> 8);
        T0RL = (uint8)temp;

        TMOD = TMOD & 0XF0;
        TMOD = TMOD | 0X01;
        TH0 = T0RH;
        TL0 = T0RL;
        EA = 1;
        ET0 = 1;
        TR0 = 1;
}

void led\_scan()//LED扫描函数，每个1ms扫描一次
{
        static uint8 index = 0;

        P0 = 0X00;
        switch(index)
        {
                case 0:ADDRC=1;ADDRB=1;ADDRA=1;P0=led_char[AD_value%10];break;
                case 1:ADDRC=1;ADDRB=1;ADDRA=0;P0=led_char[AD_value/10%10];break;
                case 2:ADDRC=1;ADDRB=0;ADDRA=1;P0=led_char[AD_value/100];break;
                default:break;
        }
        index++;
        if(index >= 3)
        {
                index = 0;
        }
}

void interrupt\_timer0() interrupt 1//定时器0的中断函数
{
        static uint16 cnt = 0;

        TH0 = T0RH;
        TL0 = T0RL;

        led\_scan();
        cnt++;
        if(cnt >= 300)
        {
                cnt = 0;
                flag_300ms = 1;
        }
}


程序源码和仿真文件资源

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链接：https://pan.baidu.com/s/1TRFVmeDbMTWW1B22HIXUcQ 
提取码：iltp