#include<reg52.h>

#include<intrins.h>

#define uint unsigned int 

#define uchar unsigned char

sbit P23=P2^3;

sbit P35=P3^5;

sbit P36=P3^6;

sbit P37=P3^7;

sbit P20=P2^0;

sbit P21=P2^1;

sbit P22=P2^2;

sbit AD_EOC=P3^0;

sbit AD_START=P3^3;

sbit AD_OE=P3^4;

sbit LCD_RS=P3^1;

sbit LCD_EN=P3^2;

 void Lcd_Delay1ms(uint c) ;

 void delay(uint x);

 void LcdWriteCom(uchar com);

 void LcdWriteData(uchar dat);

 void LCD_word(uchar addr,uchar *s);

 void LCD_DATA(uchar addr,float dat);

 void LcdInit();

void main()

{

    float DATA,temp2;

    char temp1;

    LcdInit();   //液晶初始化 

    LCD_word(0x80,"voltage:");

    while(1)

   {

     P2=0xF0;

        temp1=P2;

   temp1=temp1&0xf0;

   switch(temp1)

   {

      case 0x80: P23=0,P35=1,P36=1,P37=1;P20=0,P21=0,P22=0;break;

    case 0xc0: P23=1,P35=0,P36=1,P37=1,P20=1,P21=0,P22=0;break;

    case 0xE0: P23=1,P35=1,P36=0,P37=1,P20=0,P21=1,P22=0;break;

           case 0xF0: P23=1,P35=1,P36=1,P37=0,P20=1,P21=1,P22=0;break;

       }

AD_START=0; 

AD_OE=0;

AD_START=1;

_nop_();

AD_START=0;

while(!AD_EOC);   

AD_OE=1;

temp2=P1;

AD_OE=0;

DATA=temp2/255.0*5.0;

temp1=P2;

temp1=temp1|0xf8;

switch(temp1)

         {

    case 0xf8:DATA=DATA*1;break; //2v

case 0xf9:DATA=DATA*10;break; //20

case 0xfa:DATA=DATA*100;break; //200

    case 0xfb:DATA=DATA*1000;break;  //500

         }

      LCD_DATA(0x89,DATA);

 LCD_word(0x80+15,"V");

      }

}

void Lcd_Delay1ms(uint c)   //误差 0us

{

uchar a,b;

for (; c>0; c--)

{

for (b=199;b>0;b--)

{

 for(a=1;a>0;a--);

}      

}

}

void delay(uint x)

{

uint a,b;

for(a=x;a>0;a--)

for(b=10;b>0;b--); 

}

void LcdWriteCom(uchar com)  //写入命令

{   

   P0 = com;     //放入命令

LCD_RS=0;

LCD_EN=0;

LCD_EN = 1;          //写入时序

Lcd_Delay1ms(5);  //保持时间

LCD_EN = 0;

}

void LcdWriteData(uchar dat) //写入数据

{

    P0 = dat; //写入数据

    LCD_RS=1;

LCD_EN = 0;

Lcd_Delay1ms(5);   //保持时间

LCD_EN = 1;   //写入时序

Lcd_Delay1ms(5);   //保持时间

LCD_EN = 0;

}

void LCD_word(uchar addr,uchar *s)

{

    LcdWriteCom(addr);

    delay(20);

    while(*s>0)

    {

      LcdWriteData(*s);s++;

    }

}

void LCD_DATA(uchar addr,float dat)

{

int bai,shi,ge,shifen,baifen,qianfen;

uint num;

num=(uint)(dat*100);

bai=num/10000;

shi=num%10000/1000;

ge=num%10000%1000/100;

shifen=num%10000%1000%100/10;

baifen=num%10;

qianfen=num/1;

LcdWriteCom(addr);

LcdWriteData(bai+0x30);

LcdWriteData(shi+0x30);

LcdWriteData(ge+0x30);

LcdWriteData(0x2E);

LcdWriteData(shifen+0x30);

LcdWriteData(baifen+0x30);

}

void LcdInit()  //LCD初始化子程序

{

LcdWriteCom(0x38);  //开显示

Lcd_Delay1ms(10); 

LcdWriteCom(0x0c);  //开显示不显示光标

Lcd_Delay1ms(10); 

LcdWriteCom(0x06);  //写一个指针加1

Lcd_Delay1ms(10); 

LcdWriteCom(0x01);  //清屏

Lcd_Delay1ms(10); 

}