C51单片机和ADC0832芯片设计数字电压表

#include "reg51.h"
#include "intrins.h"
#define uchar unsigned char
#define uint unsigned int
	
sbit cs=P1^0;
sbit clk=P1^3;
sbit DI=P1^4;
sbit DO=P1^5;
sbit CS1=P2^0;
sbit CS2=P2^1;
sbit CS3=P2^2;
sbit CS4=P2^3;

uchar adval,volt;//AD value 
uchar temp; 

uchar tab[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e}; //LED0-F common anode 

void delay(uint ms) //delay ms function
{
	uchar j; 
	while(ms--)
	{
		for(j=0;j<120;j++);
	}
}

void ADC_start() //start frunction
{
	cs=1; //start a cycle 
	_nop_();
	clk=0;
	_nop_();
	cs=0;			//when cs is 0,ADC is workable.
	_nop_();
	DI=1;
	_nop_();
	clk=1;		//frist pulse
	_nop_();
	DI=0;
	_nop_();
	clk=0;
	_nop_();
}

void ADC_read(uint CH) //AD conversion subroutine
{
	uchar i; 
	ADC_start();
	if(CH==0)			//select channel 0
	{
		clk=0;
		DI=1;
		_nop_();
		_nop_();
		clk=1;
		_nop_();
		_nop_();		//frist bit in channel 0
		clk=0;
		_nop_();
		DI=0;
		_nop_();
		_nop_();
		clk=1;
		_nop_();
		_nop_();		//second bit in  channel 0
	}
		else			//selcet channel 1
		{
			clk=0;
			DI=1;
			_nop_();
			_nop_();
			clk=1;
			_nop_();
			_nop_();
			clk=1;
			_nop_();
			_nop_();		//frist 1 bit in channel 1
			DI=1;
			_nop_();
			_nop_();
			clk=1;
			_nop_();
			_nop_();		//second bit in channel 1
		}
		clk=1;
		_nop_();
		clk=0;
		for(i=0;i<8;i++)
		{
			DI=1;
			if(DO)
			{
				temp=(temp|0x01);
			}
			else
			{
				temp=(temp&0xfe); //lastest bit AND 0
			}
			clk=0;
			_nop_();
			clk=1;
			temp=temp<<1;  //move temp 1 bit to the left
		}
		adval=temp;
	}

void volt_result() // solve function
{
	volt=adval*1.96; 		//AD value change to volt value
}

void disp_volt(uint date)		//display function
{
	CS1=1;CS2=0;CS3=0;CS4=0; //P2.0=1 , display frist lamps;
	P0=~((~tab[date/100])|0x80);		//|0X80 for display point 
	delay(1);
	P0=0xff;  // disappear
	CS1=0;CS2=1;CS3=0;CS4=0;		//P2.1=1,display second lamps; 
	P0=tab[date%100/10];
	delay(1);
	P0=0xff; 
	CS1=0;CS2=0;CS3=1;CS4=0;		//P2.2=1,display third lamps;
	P0=tab[date%10];
	delay(1);
	P0=0xff; 
	CS1=0;CS2=0;CS3=0;CS4=1;		//P2.3=1, display fourth lamps; 
	P0=tab[date%100];
	delay(1);
	P0=0xff; 
}

void main(void)  //main function
{
	P2=0xff; 		//Port initialization
	P0=0xff; 
	while(1)
	{
		ADC_read(0); // channel 0 working
		delay(1);
		volt_result();
		disp_volt(volt); //show volt value 
	}
}