直流数字电压表0_5V(4位显示)

单片机仿真实验

——直流数字电压表设计

调节电位器RV1可使其输出电压在0-5V之间变化。经AD转换后，数码管以十进制形式动态显示电位器的调节电压。

元件清单

元件类别电路符号元件名称Microprocessor ICS U1 80C51

Data Converter U3 ADC0808

Miscellaneous X1 CRYSTAL

Capacitors C1-C2 CAP

Capacitors C3 CAP-ELEC

Resistors RP1 RESPACK_8

Resistors R9/10K RES

Resistors RV1/4.7K POT-HG Qpto electronics LED 7SEG-MPX4-CC-RED 结果：

程序代码：

#include

#define uint unsigned int

#define uchar unsigned char

sbit CLK=P2^4;

sbit ST =P2^5;

sbit EOC=P2^6;

sbit OE=P2^7;

sbit P20=P2^0;

sbit P21=P2^1;

sbit P22=P2^2;

sbit P23=P2^3;

uchar code mod[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f}; uint result=0;

void delay(uint time);

void display();

Time1()interrupt 1

{

CLK=!CLK;

}

void main()

{

TMOD=0x02;

EA=1;

ET0=1;

TR0=1;

TH0=0x00;

TL0=0x00;

while(1)

{

ST=0;

ST=1;

ST=0;

while(EOC==0);

OE=1;

result=P1;

OE=0;

display();

}

}

void display()

{

uint gw,sf,bf,qf;

gw=result/51;

sf=(result*10/51)%10;

bf=(result*100/51)%10;

qf=(((result*100)%51)*10)/51;

P20=0;

P0=mod[gw]|0x80;

delay(10);

P20=1;

P21=0;

P0=mod[sf];

delay(10);

P21=1;

P22=0;

P0=mod[bf];

delay(10);

P22=1;

P23=0;

P0=mod[qf];

delay(10);

P23=1;

}

void delay(uint time) {

uint j=0;

for(;time>0;time--)

for(;j<125;j++); }