#include <reg52.h>
#include <intrins.h>
#include <math.h>
#define uchar unsigned char
#define uint unsigned int
sbit RS = P0^7;
sbit LCDEN = P0^5;
sbit rw=P0^6;
sbit BEEP=P3^6;
void delay500(void) //500us延時函數
{
uchar i;
for(i=230;i>0;i--);
}
void delayUs()
{
_nop_();
}
void delayMs(uint a)
{
uint i, j;
for(i=a; i>0; i--)
for(j=100; j>0; j--);
}
void writeComm(uchar comm)
{
RS = 0;
P2 = comm;
LCDEN = 1;
delayUs();
LCDEN = 0;
delayMs(1);
}
//寫數據:RS=1, RW=0;
void writeData(uchar dat)
{
RS = 1;
P2 = dat;
LCDEN = 1;
delayUs();
LCDEN = 0;
delayMs(1);
}
void init()
{
rw=0;
writeComm(0x38);
writeComm(0x0c);
writeComm(0x06);
writeComm(0x01);
}
void writeString(uchar * str, uchar length)
{
uchar i;
for(i=0; i<length; i++)
{
writeData(str[i]);
}
}
/*******************************DS18B20*******************************/
sbit dq = P3^7;
void dqInit()
{
unsigned int i;
dq = 0;
i = 100;
while(i>0) i--;
dq = 1;
i = 4;
while(i>0) i--;
}
void dqWait()
{
unsigned int i;
while(dq);
while(~dq);
i = 4;
while(i > 0) i--;
}
bit readBit()
{
unsigned int i;
bit b;
dq = 0;
i++;
dq = 1;
i++; i++;
b = dq;
i = 8;
while(i>0) i--;
return b;
}
unsigned char readByte()
{
unsigned int i;
unsigned char j, dat;
dat = 0;
for(i=0; i<8; i++)
{
j = readBit();
dat = (j<<7)|(dat>>1);
}
return dat;
}
void writeByte(unsigned char dat)
{
unsigned int i;
unsigned char j;
bit b;
for(j=0; j<8; j++)
{
b = dat & 0x01;
dat >>= 1;
if(b)
{
dq = 0;
i++;
dq = 1;
i = 8;
while(i>0)
i--;
}
else
{
dq = 0;
i = 8;
while(i>0)
i--;
dq = 1;
i++;
}
}
}
void sendChangeCmd()
{
dqInit();
dqWait();
delayMs(1);
writeByte(0xcc);
writeByte(0x44);
}
void sendReadCmd()
{
dqInit();
dqWait();
delayMs(1);
writeByte(0xcc);
writeByte(0xbe);
}
int getTmpValue()
{
unsigned int tmpvalue;
int value;
float t;
unsigned char low, high;
sendReadCmd();
low = readByte();
high = readByte();
tmpvalue = high;
tmpvalue <<= 8;
tmpvalue |= low;
value = tmpvalue;
t = value * 0.0625;
value = t*100+(value>0?0.5:-0.5); //大于0加0.5, 小于0減0.5
return value;
}
void display(int v)
{
unsigned char count;
unsigned char datas[] = {0, 0, 0, 0, 0};
unsigned int tmp = abs(v);
datas[0] = tmp / 10000;
datas[1] = tmp % 10000 / 1000;
datas[2] = tmp % 1000 / 100;
datas[3] = tmp % 100 / 10;
datas[4] = tmp % 10;
writeComm(0xc0+3);
if(v < 0)
{
writeString("- ", 2);
}
else
{
writeString("+ ", 2);
}
if(datas[0] != 0)
{
writeData('0'+datas[0]);
}
for(count = 1; count != 5; count++)
{
writeData('0'+datas[count]);
if(count == 2)
{
writeData('.');
}
}
}
/*******************************DS18B20*******************************/
void main()
{
uchar table[] = " Temperature: ";
int i;//i儲存轉換后的溫度值
uchar j;
sendChangeCmd();
init();
writeComm(0x80);
writeString(table, 16);
while(1)
{
delayMs(1000); //溫度轉換時間需要750ms以上
writeComm(0xc0);
i = getTmpValue();
if(i > 2300)
{
for(j=200;j>0;j--)
{
BEEP=~BEEP; //輸出頻率1KHz
delay500(); //延時500us
}
for(j=200;j>0;j--)
{
BEEP=~BEEP; //輸出頻率500Hz
delay500(); //延時1ms
delay500();
}
}
display(i);
sendChangeCmd();
}
}
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