I need help for DS18B20

[electro22]

Hi all,

I am using Pic16f877A and I wanna use DS18B20 sensor with it. I have been searcing about this for a long time I had many codes about that but I havent managed to work any of them yet.

here my last sample codes are;

1- for reading DS18B20;

int get_temp(void)
{
touch_present();
touch_write_byte(0xCC);
touch_write_byte(0x44);
delay_ms(0.4);
touch_present();
touch_write_byte(0xCC);
touch_write_byte(0xBE);
return touch_read_byte();
}


2- one wire communication

#ifndef TOUCH_PIN
#define TOUCH_PIN PIN_C0
#if defined(__PCH__)
#bit TOUCH_PIN_BIT = 0xF8C.0
#else
#bit TOUCH_PIN_BIT = 6.0
#endif
#endif


BYTE touch_read_byte() {
BYTE i,data;

for(i=1;i<=8;++i) {
output_low(TOUCH_PIN);
delay_us(14);
output_float(TOUCH_PIN);
delay_us(5);
shift_right(&data,1,input(TOUCH_PIN));
delay_us(100);
}
return(data);
}

BYTE touch_write_byte(BYTE data) {
BYTE i;

for(i=1;i<=8;++i) {
output_low(TOUCH_PIN);
delay_us(10);
if(shift_right(&data,1,0)) {
output_high(TOUCH_PIN);
delay_us(10);
if(!TOUCH_PIN_BIT)
return(0);
} else {
output_low(TOUCH_PIN);
delay_us(10);
if(TOUCH_PIN_BIT)
return(0);
}
delay_us(50);
output_high(TOUCH_PIN);
delay_us(50);
}
return(TRUE);
}

BYTE touch_present() {
BOOLEAN present;

output_low(TOUCH_PIN);
delay_us(500);
output_float(TOUCH_PIN);

delay_us(5);

if(!input(TOUCH_PIN))
return(FALSE);
delay_us(65);
present=!input(TOUCH_PIN);
delay_us(240);
if(present)
return(TRUE);
else
return(FALSE);
}


I ll be so happy ıf anyone can say where my error is or send me a worked one.
thanks very much in advance..

[ckielstra]

When posting code please use the 'code' buttons to preserve the layout of your program. Easier reading of your program will get you quicker and better answers.

You are not allowed to post the code of the CCS drivers in this forum. We all have these drivers so it will do when you post the name of the driver you used.

[electro22]

Thanks for your advice I am new here thats why ı dont know well the rules..
by the way I did not manage to work the codes which u sent me..It gave errors again. I dont know what ı can do more.

[ckielstra]

What is the error text you get?
Post a complete but short program showing your problems.

[electro22]

the error message: STDOUT not defined maybe missing #use RS232 in call one


I cant understand that because I am not using RS232 in anywhere in my code.

By the way thanks again

[ckielstra]

In my examples I used the printf command. If you don't specify a destination then printf will send the data to the STDOUT port, this defaults to RS232. If you don't have RS232, and you didn't specify another port for STDOUT, than this explains your error.

Just wondering, how are you going to present the temperature to the user?

[electro22]

I am sending data to LCD display and LCD is connecting to B port. Sorry maybe I am little stupid at this but still I cant get how I work that out?

[ckielstra]

Are you using lcd.c as the LCD-driver?

If yes, than you can show the temperature with:

[electro22]

yes I am using LCD.C at the begining. I did all things you said. It doesnt give any error But in Proteus, still LCD is not showing any temperature.
I used also the different one wire code, Ds18B20 and main code but they show only one value and it is wrong it is not the right temperature. I got these codes from Code library.

What u think Can ı manage to work the code what we have been talking or Do ı have to change them?

[ckielstra]

Many things can be wrong, without code example I can't help you any further.
Post your main.c and the code for reading the DS18B20.

What is your compiler version number?