main.c

三星ARM7的Linux系统下的DA程序

//******************************************************
//Chinese Academy of Sciences, Institute of Automation
//File Name:	main.c
//Description: 	DAC Test
//Author:	JuGuang,Lee
//Date:		
//******************************************************	

#define DAC		(*(volatile unsigned char *)0x03F00070) //DAC 

#define LED1  		(*(volatile unsigned char*)0x03F00000) //DS4
#define LED2  		(*(volatile unsigned char*)0x03F00010) //DS3
#define LED3  		(*(volatile unsigned char*)0x03F00020) //DS2
#define LED4  		(*(volatile unsigned char*)0x03F00030) //DS1

unsigned char led[11]={0xb7,0x06,0x73,0x57,0xc6,0xd5,0xf5,0x07,0xf7,0xd7,0x0};

void Delay(unsigned int);
void Disp(unsigned char adc);

int C_Entry()
{	
	unsigned char dac_value;
	dac_value=0;	
	while(1){
		DAC=dac_value;		//	将数字量送到DAC端口
		Disp(dac_value);	//	同时在LED上显示当前数字量
		Delay(5);		//	延时，等待DA转换结束
		dac_value=dac_value+1;	//	数字量增加
		if(dac_value>255)	//	如果数字量大于255，重新从0开始
			dac_value=0;
		
		}

	return 0;	
}

void Disp(unsigned char adc)
{
	
	unsigned char temp;
	temp=adc;
	adc=adc/1000;
	LED1=led[adc];
	temp=temp-1000*adc;
	adc=temp;
	adc=adc/100;
	LED2=led[adc];
	temp=temp-100*adc;
	adc=temp;
	adc=adc/10;
	LED3=led[adc];
	temp=temp-10*adc;
	LED4=led[temp];
}
void Delay(unsigned int x)
{
	unsigned int i,j,k;
	for(i=0;i<=x;i++)
		for(j=0;j<255;j++)
			for(k=0;k<255;k++);
}