【單片機】DS18B20

lcd.c

#include <reg52.h>
#include "../delay/delay.h"
#include "lcd.h"

/*====================================================
                 判斷寫入命令/數據函數
=====================================================*/
void lcd_write(unsigned char byte, unsigned char flag)
{
    if(flag)
	{
	    RS = 1;        //選擇數據寄存器
	}
	else
	{
	    RS = 0;        //選擇指令寄存器
	}
	
	RW = 0;            //寫
	E = 1;             //選中LCD
	LCDPORT = byte;
	delay_us(5);       //穩定
	E = 0;             //失能LCD
}

/*====================================================
                    LCD初始化函數
=====================================================*/
void lcd_init()
{
    delay_ms(15);
	lcd_write(0x38,LCD_WRITE_COM);    //顯示8位數據接口，兩行顯示，5*7點陣字符
	delay_ms(5);
	lcd_write(0x38,LCD_WRITE_COM);
	delay_ms(5);
	lcd_write(0x38,LCD_WRITE_COM);
	delay_ms(5);
	lcd_write(0x38,LCD_WRITE_COM);
	delay_ms(5);
	lcd_write(0x08,LCD_WRITE_COM);    //關閉顯示，關閉光標的閃爍
	delay_ms(5);
	lcd_write(0x01,LCD_WRITE_COM);    //清屏
	delay_ms(5);
	lcd_write(0x06,LCD_WRITE_COM);    //設置指針方式，畫面不平移
	delay_ms(5);
	lcd_write(0x0c,LCD_WRITE_COM);    //打開顯示
	delay_ms(5);
}

/*====================================================================================
                                 寫入字符函數
函數原型：void lcd_dis_byte(unsigned char x, unsigned char y, unsigned char byte);
說明：x爲行（1——2），y爲列（1——8）。
=====================================================================================*/
void lcd_dis_byte(unsigned char x, unsigned char y, unsigned char byte)
{
    unsigned char add;
	
    if(((0 == x) || (x > 2)) || ((0 == y) || (y > 16)))
	{
	    return ;
	}
	
    add = 0x80 + (x - 1) * 0x40 + (y - 1);
	
	lcd_write(add,LCD_WRITE_COM);	     
	lcd_write(byte,LCD_WRITE_DATA);
}

/*====================================================================================
                                  寫入字符串函數
函數原型：void lcd_dis_str(unsigned char x, unsigned char y, unsigned char *disdata);
說明：x爲行（1——2），y爲列（1——8）。
=====================================================================================*/
void lcd_dis_str(unsigned char x, unsigned char y, unsigned char *disdata)
{
    unsigned char add;
	
    if(((0 == x) || (x > 2)) || ((0 == y) || (y > 16)))
	{
	    return ;
	}
	
    add = 0x80 + (x - 1) * 0x40 + (y - 1);
	lcd_write(add,LCD_WRITE_COM);
	
    while(*disdata != '\0')
	{	    
	    lcd_write(*disdata,LCD_WRITE_DATA);
		disdata++;
	}
}

#if 0
/*===========================================================================
                                時間顯示函數
============================================================================*/
void lcd_dis_time()
{
    lcd_write(0x80 + 4,LCD_WRITE_COM);
	lcd_write((hour / 10) + 0x30,LCD_WRITE_DATA);
	lcd_write((hour % 10) + 0x30,LCD_WRITE_DATA);
	lcd_write((min / 10) + 0x30,LCD_WRITE_DATA);
	lcd_write((min % 10) + 0x30,LCD_WRITE_DATA);
	lcd_write((sec / 10) + 0x30,LCD_WRITE_DATA);
	lcd_write((sec % 10) + 0x30,LCD_WRITE_DATA);
}
#endif

ds18b20.c

#include <reg52.h>
#include <intrins.h>
#include <stdio.h>
#include "./lcd/lcd.h"
#include "./delay/delay.h"

sbit ds = P1^0;

bit ack = 0;

/*=================================================================
                            復位DS18B20
==================================================================*/
void ds_reset()
{
    ds = 1;
	ds = 0;
	delay_us(200);
	delay_us(100);        //480-960us,800us
	ds = 1;               //free ds
	delay_us(30);
	if(0 == ds)
	{
	    ack = 1;
	}
	else
	{
	    ack = 0;
	}
	
	delay_us(200);
	delay_us(100);
}

/*=================================================================
                       向DS18B20中寫入一個字節
==================================================================*/
void ds_send_byte(unsigned char byte)
{
    unsigned char i;
	
	for(i = 0; i < 8; i++)
	{
	    ds = 0;
		
		_nop_();
		_nop_();
		
		ds = byte & 0x01;
		byte >>= 1;
		
		delay_us(30);
		
		ds = 1;
	}
	
	delay_us(30);
}

bit ds_read_bit()
{
    bit temp;
	
	ds = 1;
	ds = 0;
	
	_nop_();
	_nop_();
	
	ds = 1;
	temp = ds;
	delay_us(30);
	
	return temp;
}

unsigned char ds_read_byte()
{
    unsigned char i;
	unsigned char j;
	unsigned char k;
	
	for(i = 0; i < 8; i++)
	{
	    j = ds_read_bit();
	    k = (j << 7) | (k >> 1);
	}
	
	return k;
}

void main()
{
    unsigned char a;
	unsigned char disbuf[20];

	unsigned int temp;	
	unsigned int b;	
	
	float temperature;
	
	lcd_init();
	
    while(1)
	{
	    ds_reset();
	    ds_send_byte(0xcc);
		ds_send_byte(0x44);
		
		ds_reset();
	    ds_send_byte(0xcc);
		ds_send_byte(0xbe);
		
		a = ds_read_byte();
		b = ds_read_byte();
	
        temp = (b << 8) | a;
        temperature = (float)temp * 0.0625;

        sprintf(disbuf,"Temp is %7.3f",temperature);
        lcd_dis_str(1,1,disbuf);		
	}
}