# include & ltintrins.h & gt
# include & lt math. H & gt// Use the absolute value function abs ()
# Define uchar unsigned characters
# Define uint unsigned integer
sbit ds=p2^ 1； //sbit ds=p3^2； //DS 18B20
sbit duan=p2^6；
sbit wei=p2^7；
Ucal I;
Unsigned character code table []={0x3f, 0x06, 0x5b, 0x4f,
0x66、0x6d、0x7d、0x07、
0x7f，0x6f，0x00，0x 40 }； //0x00 is the 0x40 display "-"(minus sign) used in the display function.
//****************************************************************
Invalid delay (uchiri)
{
uint j；
When (I-)
{
for(j = 0； j & lt 125; j++)；
}
}
//****************************************************************
//Delay function. For 1 1.0592MHz clock, for example, i= 10, the delay is about10 ms. 。
void dsInit()
{
//For 1 1.0592MHz clock, the time of an i++ operation exceeds 8us.
Unsigned int I；;
ds = 0；
I = 100； //Pull down about 800us, which is more than the 480us required by the protocol.
while(I & gt； 0)I-；
ds = 1； //Generate a rising edge and enter the waiting state.
I = 4；
while(I & gt； 0)I-；
}
void dsWait()
{
Unsigned int I；;
while(ds)； //Wait for the reply signal
while(~ ds)； //Response pulse detected
I = 4；
while(I & gt； 0)I-；
}
//Read a bit of data from DS 18B20.
//Read a little, so that DS 18B20 is one cycle lower and then two cycles higher.
//After that, DS 18B20 will output one bit of data lasting for a period of time.
Bit read bit ()
{
Unsigned int I；;
B position;
ds = 0；
i++； //The delay is about 8us, which meets the protocol requirements and keeps at least 1us.
ds = 1；
i++；
i++； //The delay is about 16us, at least 15us meets the protocol requirements.
b = ds
I = 8；
while(I & gt； 0)I-； //The delay is about 64us, which meets the requirement that the reading time slot is not less than 60us.
Return to b;
}
//Read a byte of data by calling readBit ().
Unsigned character read byte ()
{
Unsigned int I；;
Unsigned characters j, dat
dat = 0；
for(I = 0； I<8; i++)
{
j = read bit()；
//Read the least significant data first.
dat =(j & lt； & lt7)|(dat & gt； & gt 1);
}
Return dat
}
//Write one byte of data to DS 18B20.
Void writeByte (unsigned character data)
{
Unsigned int I；;
Unsigned character j;
B position;
for(j = 0； j & lt8; j++)
{
b = dat & amp0x 0 1；
dat & gt& gt= 1;
//Write 1. After decreasing DQ 15us, increase DQ within 15us~60us, that is, write 1.
If (b)
{
ds = 0；
i++；
i++； //Pull down about 16us, and the symbol is required to be within 15~60us.
ds = 1；
I = 8； while(I & gt； 0)I-； //The delay is about 64us, which meets the requirement that the write time slot is not less than 60us.
}
Otherwise//write "0" to low DQ 60 us ~ 120 us.
{
ds = 0；
I = 8； while(I & gt； 0)I-； //Pull down about 64us, and the symbol is required.
ds = 1；
i++；
i++； //The whole process of writing 0 time slot has exceeded 60us, so there is no need to delay 64us like writing 1.
}
}
}
//send a temperature conversion command to DS 18B20.
void sendChangeCmd()
{
dsInit()； //initialize DS 18B20. Whatever the command is, initialize it first.
ds wait()； //Wait for a reply from DS 18B20.
Delay (1); //delay 1ms, because DS 18B20 will pull down DQ 60~240us as the reply signal.
write byte(0x cc)； //Write the skip sequence number command word Skip Rom
write byte(0x 44)； //Write the temperature conversion command word convert t.
}
//Send a command to read data to DS 18B20.
void sendReadCmd()
{
//EA = 0； //Turn off the interrupt, because the interrupt entering the display will affect the reading and writing timing of DS 18B20.
dsInit()；
ds wait()；
Delay (1);
write byte(0x cc)； //Write the skip sequence number command word Skip Rom
write byte(0x be)； //Write read data command word read temporary storage
//EA = 1；
}
//Get the current temperature value
int getTmpValue()
{
Unsigned int tmpvalue
Int value; //Store the temperature value
Floating t;
Unsigned characters are low and high;
//EA = 0；
sendReadCmd()；
//Read two bytes of data continuously.
low = read byte()；
High = readbyte ();
//Combine the upper and lower bytes into an integer variable.
//Negative numbers are represented by complement in the computer.
//If it is negative, the read value is represented by complement, which can be directly assigned to the value of type int.
Tmpvalue = high;
tmpvalue & lt& lt= 8;
Tmpvalue |= low;
value = tmpvalue
//ds 18b 20 has a default resolution of 12 bits and an accuracy of 0.0625 degrees, that is, the lowest bit of the read-back data represents 0.0625 degrees.
T = value * 0.0625;
//Enlarge 100 times, so that two decimal places can be displayed, and the third decimal place can be divided into four parts and five parts.
//If t= 1 1.0625, after calculation, the value is = 1 106, that is, 1 1.06 degrees.
//For example, t=- 1 1.0625, after counting, value =-1 106, that is-1 1.06 degrees.
value = t * 100+(value & gt； 0 ? 0.5 : -0.5); //More than 0 plus 0.5, less than 0 minus 0.5
Return value;
//EA = 1；
}
/*
void Init_timer0()
{
TMOD = 0x 0 1；
TH0 = th0
TL0 = tl0
EA = 1；
ET0 = 1；
TR0 = 1；
} */
Empty display (int dd)
{
uchar SH，SZ，SL，GH，GL，I，temp
uchar dis[8]={ 10， 10， 10， 10， 10， 10， 10， 10 }； The number from //5 to 8 is 10, and the corresponding segment code is 0x00, which means it is not displayed.
uint dda
DDA = ABS(DD)；
SH = DDA/ 10000；
SZ = DDA % 10000/ 1000；
SL = DDA % 1000/ 100；
GH = DDA % 100/ 10；
GL = DDA % 10；
dis[0]= GL；
dis[ 1]= GH；
dis[2]= SL；
if((SZ = = 0)& amp； & amp(SH==0))
dis[3]= 10；
other
dis[3]= SZ；
if(DD & lt； 0)
dis[4]= 1 1； //is negative temperature, and "-"is displayed.
other
{
If (SH==0)
dis[4]= 10； //If the high temperature is 0, it will not be displayed.
other
dis[4]= SH；
}
temp = 0xbf
for(I = 0； I<8; i++)
{
P0 = 0xff
Wei =1;
temp=_cror_(temp， 1)；
P0 = temperature;
Wei = 0;
P0 = 0；
Segment =1;
If (i==2)
{
P0 = 0x 80 | table[dis[2]]；
}
other
P0 = table[dis[I]]；
Segment = 0;
Delay (1);
}
/*
P0 = 0xff
Wei =1;
P0 = 0xdf
Wei = 0;
P0 = 0；
Segment =1;
P0 = Table [GL];
Delay (1);
Segment = 0;
P0 = 0xff
Wei =1;
P0 = 0xef
Wei = 0;
P0 = 0；
Segment =1;
P0 = Table [GH];
Delay (1);
Segment = 0;
P0 = 0xff
Wei =1;
P0 = 0xf7
Wei = 0;
P0 = 0；
Segment =1;
P0 = table[SL]| 0x 80；
Delay (1);
Segment = 0;
P0 = 0xff
Wei =1;
P0 = 0xfb
Wei = 0;
P0 = 0；
Segment =1;
P0 = Table [SZ];
Delay (1);
Segment = 0;
P0 = 0xff
Wei =1;
P0 = 0xfd
Wei = 0;
P0 = 0；
Segment =1;
P0 = table [sh];
Delay (1);
Segment = 0;
P0 = 0xff
Wei =1;
P0 = 0xff
Wei = 0; */
}
void main()
{
int tempvalue 1；
//init()；
//Init _ timer 0()；
while( 1)
{
//Start temperature conversion
sendChangeCmd()；
tempvalue 1 = getTmpValue()；
display(tempvalue 1)；
}
}
//I have successfully changed the port according to my own hardware.