#include
#include
#define uint unsigned int
#define uchar unsigned char
sbit dula=P2^6;
sbit wela=P2^7;
unsigned char j,k;
unsigned char a,b;
sbit DS=P2^2;
//define interface
uint temp;
// variable of temperature
uchar flag1;
// sign of the result positive or negative
sbit beep=P2^3;
void display1(unsigned char);
uchar code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,
//数码管编码
0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
unsigned char code table1[]={0xbf,0x86,0xdb,0xcf,0xe6,0xed,0xfd,
0x87,0xff,0xef};
void delay1(uint count)
//delay
{
uint i;
while(count)
{
i=200;
while(i>0)
i--;
count--;
}
}
///////功能:串口初始化,波特率9600，方式1///////
void Init_Com(void)
{
TMOD = 0x20;
PCON = 0x00;
SCON = 0x50;
TH1 = 0xFd;
TL1 = 0xFd;
TR1 = 1;
}
void dsreset(void)
//send reset and initialization command
{
uint i;
DS=0;
i=103;
while(i>0)i--;
DS=1;
i=4;
while(i>0)i--;
}
bit tmpreadbit(void)
//read a bit
{
uint i;
bit dat;
DS=0;i++;
//i++ for delay
DS=1;i++;i++;
dat=DS;
i=8;while(i>0)i--;
return (dat);
}
uchar tmpread(void) //read a byte date
{
uchar i,j,dat;
dat=0;
for(i=1;i>1); //读出的数据最低位在最前面，这样刚好一个字节在DAT里
}
return(dat);
}
void tmpwritebyte(uchar dat) //write a byte to ds18b20
{
uint i;
uchar j;
bit testb;
for(j=1;j>1;
if(testb)
//write 1
{
DS=0;
i++;i++;
DS=1;
i=8;while(i>0)i--;
}
else
{
DS=0;
//write 0
i=8;while(i>0)i--;
DS=1;
i++;i++;
}
}
}
void tmpchange(void)//DS18B20 begin change
{
dsreset();
delay1(1);
tmpwritebyte(0xcc);// address all drivers on bus
tmpwritebyte(0x44);//initiates a single temperature conversion
}
uint tmp()
//get the temperature
{
float tt;
uchar a,b;
dsreset();
delay1(1);
tmpwritebyte(0xcc);
tmpwritebyte(0xbe);
a=tmpread();
b=tmpread();
temp=b;
temp0;a--)
{ display2(tmp());
}
}
只是通过P2^2口进行读取哦，那该怎么理解？
串口初始化如何让理解，波特率起到什么作用？
主程序是 void main（）
{while（1）
wendu（)；
}
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