adc0809.c

51单片机及其C语言程序开发实例第8章节

#include <reg51.h>
#include "ADC0809.h"

//短延时函数：ShortDelay()
void nNop(uchar i)
{
	for(;i>0;i--) ;
	}
	
//长延时函数：LongDelay()
void LongDelay(uint i)
{
	uint j;
	for(;i>0;i--)
		{ for(j=1000;j>0;j--);}
	}
	
//启动A/D转换函数：StartADC()
void  StartADC(uchar Address)
{
	PinC = (bit) (Address & 0x04);
	PinB = (bit) (Address & 0x02);
	PinA = (bit) (Address & 0x01);
	PinSTART = 0;
	}
	
//等待A/D转换结束函数：WaitADCEnd()
void  WaitADCEnd(void)
{
	while(!PinEOC) ;
	}
	
//读取A/D转换后的数据函数：ReadData()
uint ReadData(void)
{
	uint temp;
	WaitADCEnd();
	PinOE = 0;
	nNop(2);
	temp = PinData & 0xff; 
	return(temp);
	}