AT89C51 MCU digital voltmeter development, measuring range 0 ~ 5V, proteus simulation, schematic diagram, PCB and C program, etc

The design requirements
1. With MCS-51 Series single chip microcomputer as the core device , Design a simple DC digital voltmeter ;
2. Voltage range ：0~5V;
3. Minimum resolution ：0.01V;
4. Less components are used , The cost is low , And the measurement accuracy and reliability are high ;

System Overview
This design is based on Atmel 51 A digital voltmeter system based on MCU development platform and automatic control principle .

The system adopts AT89C51 Single chip microcomputer as the control core , With ADC0809 Analog to digital conversion chip , Realize range 0 To 5V Sampling of measured voltage data ;LCD1602 Character LCD displays the measured voltage value .

meanwhile , The measurement accuracy of digital voltmeter is 0.01V, It can meet the general measurement requirements , The system framework is shown in the figure below .

Simulation circuit diagram


Schematic diagram

PCB chart

Analysis of simulation results
open Proteus Simulation file , File suffix DSN. Double click the MCU , load DianYa.hex file （ be located C In the program folder ）, Run the simulation , The results are shown in the following figure .

And you can see that ,LCD Show AD Switching channels IN0 voltage （Voltage） The size is 1.84V, use Proteus The software comes with a voltmeter （Volts） The result of the measurement is 1.85V, Both occasionally 0.01V The deviation of , It belongs to the normal phenomenon of simulation .

Slide the rheostat by clicking RP2 Up and down red arrows , Simulate the change of measured voltage value （0~5V Between ）,LCD Real time tracking and display of voltage changes .

The figure below shows how to adjust the sliding rheostat ,LCD The displayed voltage value is 4.25V, And Volts The voltmeter shows the same result .

in summary , Digital voltmeter Proteus The running effect of simulation design meets the design requirements .

part C Code

#include"include.h"
#define TIME0H 0x3C
#define TIME0L 0xB0
uchar uc_Clock=0;		// Timer 0 Interrupt count 
bit b_DATransform=0;

void vShowVoltage(uint uiNumber)
{
    
	uchar ucaNumber[3],ucCount;
	if(uiNumber>999)					
		uiNumber=999;
	ucaNumber[0]=uiNumber/100;								// Store each bit of the calculated number in the array .
	ucaNumber[1]=(uiNumber-100*(int)ucaNumber[0])/10;							
	ucaNumber[2]=uiNumber-100*(int)ucaNumber[0]-10*ucaNumber[1];
	for(ucCount=0;ucCount<3;ucCount++)
	{
    
		vShowOneChar(ucaNumber[ucCount]+48);				// Output one by one from the first to the last .
		if(ucCount==0)
			vShowOneChar('.');
	}
}
void main()
{
    
	TMOD=0x01;			// Timer 0, Pattern 1.
	TH0=TIME0H;
	TL0=TIME0L;
	TR0=1;				// Start timer .
	ET0=1;				// On timer interrupt .
	EA=1;				// General interruption 
	vdInitialize();
	vWriteCMD(0x84);	   // Write display start address （ The first line is 4 A place ）
	vShowChar("voltage");
	vWriteCMD(0xC9);     
	vShowChar("(V)");
	while(1)
	{
    
		if(b_DATransform==1)
		{
    
			b_DATransform=0;
			vWriteCMD(0xC4);
			vShowVoltage(uiADTransform());
		}
	}
}

Shared content

（1） be based on 51 MCU digital voltmeter design paper complete version ;
（2）C Program ;
（3）Proteus Simulation file ;
（4） Schematic diagram and PCB file ;
（5）Visio flow chart ;
（6） List of components ;
（7） Reference material ;

Content as shown





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