main.c

TLC1549做的电压表

#include <reg52.h>
#include <absacc.h>

#define uint unsigned int
#define SEG1 XBYTE[0xffec]
#define SEG2 XBYTE[0xffed]
#define SEG3 XBYTE[0xffee]
#define SEG4 XBYTE[0xffef]
#define SUM 50 //多次测量求平均值次数
#define VREF 4999//放大1000倍

code unsigned char ledmap[]= //共阴LED数码管译码表
{	
	0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,//0-9不带小数点
	0x40,0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10 //0-9带小数点	
};

//接口定义
sbit CS = P1^5;
sbit DA = P1^6;
sbit CK = P1^7;

//读取ADC结果函数
unsigned int get_data(void)
{
  unsigned char i;
  unsigned int temp = 0;
  CS = 0;   //开启控制电路，使能DA和CK IO引脚；
  for(i=0;i<10;i++)  //采集10次 ，即10bit
  { 
    CK = 0;        
    temp <<= 1;
    if(DA) temp++;  
    CK = 1;
  }
  CS = 1;
  return(temp);
}

void delay(unsigned char i) //延时子程序
{ 
	while(--i);
}


main()
{	
	unsigned long int temp;
	unsigned char i;
	CS = 1;  //禁止I/O CLOCK
	i = SUM;
	temp = 0;
	while(1)
	{
		temp += get_data();
		i--;
		if(i==0)
		{				
			temp = temp / SUM;	// 取平均值		
			temp = temp * VREF;	// 转换成电压值
			temp = temp / 1023;
			// 十进制译码送数码管显示
			SEG1 = ledmap[temp/1000%10 + 10];//+10表示该位带小数点
			SEG2 = ledmap[temp/100%10];
			SEG3 = ledmap[temp/10%10];
			SEG4 = ledmap[temp%10];
			i = SUM;
			temp = 0;
		}
		delay(10); //不使用延时，测量程序延时为28us
	}
}