用ds18b20测试温度并且显示在LCD1602上

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

sbit ds = P1^0;
bit ack = 0;

sbit RS = P2^4;
sbit RW = P2^5;
sbit E  = P2^6;

#define LCDPORT P0
#define LCD_WRITE_DATA 1
#define LCD_WRITE_COM  0

void lcd1602_write(unsigned char byte,unsigned char flag)
{
if(flag)
{
RS = 1;
}
else
{
RS = 0;
}
RW = 0;
E = 1;
LCDPORT = byte;
delay_us(5);
E = 0;
}

void lcd1602_dis_str(unsigned char x, unsigned char y, unsigned char *str)
{
if((x > 15) || (y > 1))
{
return ;
}
if(0 == y)
{
lcd1602_write(0x80 + x,LCD_WRITE_COM);
}
else
{
lcd1602_write(0x80 + 0x40 + x,LCD_WRITE_COM);
}
while(*str != '\0')
{
lcd1602_write(*str,LCD_WRITE_DATA);
str++;
}
}

void lcd_init()
{
delay_ms(15);
lcd1602_write(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x08,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x01,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x06,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write(0x0c,LCD_WRITE_COM);
delay_ms(5);
}

void ds_reset()
{
ds = 1;
ds = 0;
delay_us(200);
delay_us(200);
ds = 1;
delay_us(30);
if(0 == ds)
{
ack = 1;
}
else
{
ack = 0;
}
delay_us(200);
delay_us(100);
}

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 tmp;
ds = 1;
ds = 0;
_nop_();
_nop_();
ds = 1;
tmp = ds;
delay_us(30);
return tmp;
}

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

void main()
{
unsigned char a;
unsigned int temp;
unsigned int b;

float wendu;

unsigned char disbuf[20];

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;
wendu = (float)temp * 0.0625;
sprintf(disbuf,"temp is %7.3f",wendu);
lcd1602_dis_str(0,0,disbuf);
}
}

void delay_us(unsigned char t)
{
while(--t);
}

void delay_ms(unsigned char t)
{
while(t--)
{
delay_us(245);
delay_us(245);
}
}

void delay_s(unsigned char t)
{
while(t--)
{
delay_ms(200);
delay_ms(200);
delay_ms(200);
delay_ms(200);
delay_ms(200);
}
}