#define uint8 unsigned char#define uint 16 unsigned int

_ _ configuration (wdtdis & Amplvpdis & Amphs & Amppwrtdis & Ampboldis); //Set the configuration bit

//WDTDIS: disable watchdog timer.

//LVPDIS: low voltage programming is disabled.

//HS: high-speed crystal/resonator

//PWRTDIS: disable power-on timer.

//BORDIS: disable power-off reset.

Static volatile bit dat @ (unsigned) portc * 8+2;

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

const uint8 disp[] = {0xC0，0xF9，0xA4，0xB0，0x99，0x92，0x82，0xF8，0x80，0x 90 }； //* * * Yang digital tube section code table

Volatile uint8temp _ data _ int//integer part of temperature

Volatile float temper _ data _ fla///Decimal part of temperature

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

Void ShowTemper (invalid); //Display temperature

void Get _ temper(void)； //Get temperature data

void Reset _ ds 18b 20(void)； //Reset DS 18B20

uint 8 Read _ Temp _ Data(void)； //Read temperature byte data

void delay us(uint 8 delay)； //A slight delay

void delay ms(uint 16 delay)； //millisecond delay

void Write _ 18b 20 _ Comd(uint 8 Comd)； //Write DS 18B20 instruction

Void display (uint8 chosebit, uint8data); //Single 8-bit digital tube display

/*******************************************************************************

* function name: DelayUS(uint8 delay)

* Function: 20MHZ microsecond delay.

* Entry parameter: delay

* Return: None

*******************************************************************************/

Invalid delay (uint8 delay)

{

while(-delay)；

}

/*******************************************************************************

* function name: delaymas (uint 16 delay)

* Function: 20MHZ millisecond delay.

* Entry parameter: delay

* Return: None

*******************************************************************************/

Invalid delay (uint 16 delay)

{

uint 16 I；

for(； Delay & gt0; Delay-)

for(I = 0； I & lt453; i++)；

}

/******************************************************************************

* function name: display (uint8chosebit, uint8data)

* Function: Single digital tube display

* entrance parameters: chosebit selection bit, data font.

* Return: None

*******************************************************************************/

Empty display (uint8 selection bit, uint8 data)

{

adcon 1 = 0x8E； //Set PORTA0 as analog input and others as IO ports.

Teresa & = 0xc1;

TRISD = 0x00// The data line is configured as an output.

PORTA = 0xFF

PORTA & amp= ~(0x 02 & lt； & ltchose bit)；

PORTD = data; //Send font

Drayus (200); //delay

PORTD = 0xFF// Turn off the monitor.

}

/******************************************************************************

* function name: Reset_DS 18B20(void)

* function: reset DS 18B20.

* Inlet parameters: None

* Return: None

*******************************************************************************/

Invalid reset _DS 18B20 (invalid)

{

Uint8 flag = 0; //Reset flag

while( 1)

{

dat = 0； //The data line is set to 0

Drayus (250);

Drayus (250); //Delay 500us

dat = 1； //The data line is set to 1.

Draeus (60); //Delay 60us

tris C2 = 1；

While(dat == 0) // If the data line is 0

{

Drayus (240); //delay 240us

If(dat) // If the data line is 1

{

flag = 1； //Reset succeeded, and set the success flag.

Break; //Jump out of the while(dat==0) statement.

}

other

Break;

}

If (logo)

{//If the reset is successful,

Drayus (240);

Drayus (240); //delay 480us

Break; //Jump out of the whole while( 1) statement.

}

tris C2 = 0；

}

}

/******************************************************************************

* function name: write _18b20 _ comd (uint8comd)

* function: DS 18B20 write instruction.

* entrance parameter: comd instruction

* Return: None

*******************************************************************************/

void Write _ 18b 20 _ Comd(uint 8 Comd)

{

uint8 i，temp

tris C2 = 0；

for(I = 0； I<8; I++) // A byte cycles 8 times.

{

temp = comd & amp0x 0 1； //Read the bottom bit of the instruction

comd & gt& gt= 1; //Instruct the data to shift one bit to the right.

dat = 0； //The data line is set to 0

Draeus (4); //delay 8us

If (temperature == 0)

{

dat = 0；

}

other

{

dat = 1；

}

Draeus (60); //delay 40us

dat = 1； //The data line is set to 1.

}

}

/******************************************************************************

* function name: read temporary data (void)

* Function: read the temperature sampling data of DS 18B20.

* Inlet parameters: None

* Return: data read.

*******************************************************************************/

Uint8 reads temporary data (void).

{

Uint8 i, data;

tris C2 = 0；

for(I = 0； I<8; I++) // Read a byte 8 times.

{

Data & gt& gt= 1; //The data is shifted one bit to the right.

dat = 0； //The data line is set to 0

Draeus (2); //Delay 2us

dat = 1； //The data line is set to 1.

Draeus (8); //delay 8us

tris C2 = 1；

Draeus (8); //delay 8us

If(dat) // If the read data is 1

Data | = 0x80// Highest position of data 1

Draeus (40); //delay 40us

tris C2 = 0；

}

To return (data); //Returns the read data.

}

/******************************************************************************

* function name: Get _ temple(void)

* Function: Read temperature data.

* Inlet parameters: None

* Return: None

*******************************************************************************/

void Get_temper(void)

{

uint8 temp，temp 1；

write _ 18b 20 _ Comd(0x cc)； //write skip ROM instruction

write _ 18b 20 _ Comd(0x 44)； //Write temperature conversion instruction

dat = 1； //The data line is set to 1.

Drayus (200);

Drayus (200);

reset _ ds 18b 20()； //Call the initialization reset function

write _ 18b 20 _ Comd(0x cc)；

write _ 18b 20 _ Comd(0x be)； //Write and read instructions

temp = Read_Temp_Data()。 //Read low storage temperature.

Temp & amp0x0f///take the decimal part and store it in temp _ data _ Fla

temp & gt& gt= 4; //Take the upper nibble of the lower byte.

temp 1 = Read_Temp_Data()。 //The read high bits are stored in temp 1.

temp 1 & lt； & lt= 4; //Take the lower half byte of the high byte

temp _ data _ int = temp 1 | temp； //high and low nibbles or temp _ data _ int

Tempering _ data _fla = Tempering _ data _ Fla *100/16; //Take the decimal part and store it in temp 1.

}

/******************************************************************************

* function name: show temple(void)

* Function: Display the detected temperature.

* Inlet parameters: None

* Return: None

*******************************************************************************/

Invalid display status (invalid)

{

Display(0，disp[temple _ data _ int/ 10])；

disp[temple _ data _ int % 10]& amp； 0x7F)；

Display(2，disp[(uint 8)tempent _ data _ Fla/ 10])；

Display(3，disp[(uint 8)tempent _ data _ Fla % 10])；

}

/******************************************************************************

* Number of letters: main ()

* Function: Real-time detection and display of ambient temperature.

* Inlet parameters: None

* Return: None

*******************************************************************************/

void main()

{

tris C2 = 0；

while( 1)

{

reset _ ds 18b 20()； //Reset DS 18B20

get _ temple()； //Get the temperature value

show temple()； //Display temperature

}

}