Please help with code for DS18B20

[Gabestarting]

Sorry, reading the text again i observed that i have the right sensor, i was lucky...So, the thermostat works fine, i am happy for the bas-file, however it is easier to understand than assembler. I made the circuit on a stripboard. Have a nice evening!

[fratello]

I want now to try to read the temperature with two sensors DS18B20 ; one for IN and other for OUT. It is possible ? How can I display both temperatures ?
Help, please !

[Acetronics2]

Hi, Fratello

some homework to do for you ...

take the DS18B20 Datasheet out, and look at :

1) How to get the device ID
2) How to address the device with it's ID

Buuuuuut, I do think ALL the answers you look for already are posted on this Maaarrrrrvellous Forum !!!

It's called SEARCH Function ...

Alain

PS: HELP Function momentarily out of use : New Year update ... lol

[fratello]

I try to read the serial number of my DS18B20 sensor with this code :

TRISA= %11110000 ' RA0..3=Outputs RA4=Input
TRISB= %00000111 ' RB0..RB2=Inputs, RB3..RB7=Outputs
CMCON=7 ' Disable comparators

DEFINE LCD_DREG PORTB ' LCD on port B
DEFINE LCD_DBIT 4 ' Data bits B4..B7
DEFINE LCD_RSREG PORTA ' RS on PORTA
DEFINE LCD_RSBIT 1 ' RS on A1
DEFINE LCD_EREG PORTA ' E on PORTA
DEFINE LCD_EBIT 0 ' E on A0
DEFINE LCD_BITS 4 ' LCD 4 bit mode
DEFINE LCD_LINES 2 ' 2 line LCD display

DQ Var PORTA.4 ' One-wire data pin
i Var Byte
Temp Var Byte
ReadRom Con $33

Pause 500
LCDOUT $FE, 1, $FE, $0C ' Clear display, cursor off
Pause 250

Main

OWOut DQ, 1, [ReadRom]
for i = 0 to 7
OWIn DQ, 0, [Temp]
LcdOut $FE, $80, Hex Temp
Next
LcdOut $FE, $14
LcdOut $FE, $14
Pause 1000
GoTo Main


but on display appears only "A7". What I do wrong ? Thanks !

[Darrel Taylor]

LcdOut $FE, $80, Hex Temp

The $80 moves the cursor to Line1 Column1, and it overwrites the previous values on each loop. All you see is the last loop.
<br>

[fratello]

Per aspera ad astra !!!!
I write another code :

DQ Var PORTA.4 ' One-wire data pin
i Var Byte
Temp Var Byte
ReadRom Con $33
ID VAR BYTE[8] ' Array storage variable for 64-bit ROM code


Begin:
PAUSE 500 ' Wait .5 second
LCDOUT $FE, 1, $FE, $0C ' Clear display, cursor off

Start_Convert
OWOUT DQ, 1, [$33] ' Issue Read ROM command

ID_Loop:
OWIN DQ, 0, [STR ID\8]' Read 64-bit device data into the 8-byte array "ID"
for i = 0 to 7
LcdOut HEX ID[i]
next i
END



Now I have on display : 28CAC648100A7
I think now it is correct. Can You confirm ? Thanks !

[Acetronics2]

Hi, Fratello

Looks fine

my DS shows 7A00000190DF64

read you soon

Alain