Microcontroller Example 13.1

Microcontroller Example 13.1

#include"reg51.h"
#include"stdio.h"
#define OSC  18432000L
#define BAUD 9600
#define URMD 0
#define ADC_POWER 0x80
#define ADC_FLAG 0x10
#define ADC_START 0x08
#define ADC_SPEEDLL 0x20
#define ADC_SPEEDL 0x20
#define ADC_SPEEDH 0x40
#define ADC_SPEEDHH 0x60
sfr T2H=0xD6;
sfr T2L=0xD7;
sfr AUXR=0x8E;
sfr ADC_CONTR=0xBC;
sfr ADC_RES=0xBD;
sfr ADC_RESL=0xBE;
sfr PLASF=0x9D;
unsigned char ch=4;
float voltage=0;
unsigned char tstr[5];
unsigned int tmp=0;
float old_voltage=0;
void SendData(unsigned char dat)
{
    
    
	while(!TI);
	TI=0;
	SBUF=dat;
}
void adc_int()interrupt 5
{
    
    
	unsigned char i=0;
	ADC_CONTR&=!ADC_FLAG;
	tmp=(ADC_RES*4+ADC_RESL);
	voltage=(tmp*5.0)/1024;
	sprintf(tstr,"%1.4f",voltage);
	if (voltage!=old_voltage)
	{
    
    
		old_voltage=voltage;
		SendData('\r');
		SendData('\n');
		for(i=0;i<5;i++)
		SendData(tstr[i]);
	}
	ADC_CONTR=ADC_POWER|ADC_SPEEDLL|ADC_START|ch;
}
void main()
{
    
    
	unsigned int i;
	SCON=0x5A;
	T2L=65536-OSC/4/BAUD;
	T2H=(65536-OSC/4/BAUD)>>8;
	AUXR=0x14;
	AUXR|=0x01;
	PLASF=0xFF;
	ADC_RES=0;
	ADC_CONTR=ADC_POWER|ADC_SPEEDLL|ADC_START|ch;
	for(i=0;i<10000;i++);
	IE=0xA0;
	while(1);
}