main5.c

基于at89c51单片机的mp3 ad转换实验

#include "AT89C51SND1_REG.H"
#include "MCU_UART.H"

#define LED	     P3_5

#define ADIDL 0x40
#define ADEN  0x20
#define ADEOC 0x10
#define ADSST 0x08
#define ADCS  0x01

void delay()
{
	unsigned char i,j;
	for(i=0;i<100;i++)
	   for(j=0;j<255;j++);
}
main()
{
	unsigned char i;
	unsigned char adc_value;
	init_uart();
	printu("JMBIE MP3 EXP5: A\D Convertion.\n");

	ADCLK = 0x0f;   //设置ADC的时钟分频系数
    ADCON |= ADEN;	//使能ADC
	for(i=0;i<5;i++);
	
	ADCON |= ADCS;  //选择通道0
//	ADCON &=~ADCS;	//选择通道1
    
	while(1)
	{
//	 ADCON |= ADIDL; //转换期间挂起CPU核	
	 ADCON |= ADSST; //启动转换
	 while(!(ADCON & ADEOC));	  //等待转换结束
	 ADCON &= ~ADEOC;	//软件清除结束标志
	 adc_value = ADDH;
     printu("          \r");
	 printuf("A/D = %d\r",adc_value);
     (adc_value>128)?(LED = 0):(LED = 1);
	 delay();
	}
}