picaxe readtemp function equivalent in picbasic

[MiskaA]

Hi,
This may be a completely retarded question but i have very little experience with picbasic and picaxe for that matter.
I'm working on a project and i've got a code i've written in picaxe. I've used the readtemp command but i'm unsure how i would use this in the picbasic logic.
Is there an equivalent term to use, my programming is pretty much just comparing two temperature sources (both DS18S20's) and checking for a varience between the two, then turning on an output when the difference is great enough.
Thanks in advance

[mackrackit]

These should get you going
http://rentron.com/PicBasic/PBP1-wire.htm
(http://rentron.com/PicBasic/PBP1-wire.htm)and
http://rentron.com/PicBasic/one-wire2.htm

[MiskaA]

Sorry I'm still not really grasping the concept;
my current code looks simular to this

in picaxe
readtemp 0, b0 'storage cell 1 temp
readtemp 1, b1 'storage cell 2 temp

start:
let b0=b0+30 'simulate 30 degree celcius offset
if b0>b1 then 'check if storage cell 1 is more than cell 2
high 3 'open solenoid to transfer
endif
let b0=b0-30 'return b0 to true reading

in picbasic ive written it roughly like this but unsure how to do the readtemp part or i'm possibly completely wrong all together?
trisb.0=1
trisb.1=1

cell1temp var portb.0
cell2temp var portb.1
solenoid var portb.3
start:
let cell1temp = cell1temp +30
if cell1temp > cell2temp then
high solenoid
endif
let cell1temp = cell1temp - 30

[mackrackit]

Pretty much forget the picaxe stuff. It does not look like picaxe is comparable with PBP.

Follow the example I linked to for one-wire devices. Bruce gives the best explanation I know of.

[Heckler]

MiskaA...

Here is another example on how to read the DS18B20 temp sensor... or several of them. This example is based on the same code that Mackrackit linked to.

http://www.picbasic.co.uk/forum/content.php?r=374-How-to-read-a-one-wire-DS18B20-temperature-sensor-or-nine-of-them (http://www.picbasic.co.uk/forum/content.php?r=374-How-to-read-a-one-wire-DS18B20-temperature-sensor-or-nine-of-them)

[MiskaA]

Thanks for the links, it's has given me some more insight into what i'm trying to acheive.
I'm actually using a pic16f684 and have connected the "DQ" pins of the temp sensors to their own pins on the pic chip (pins 6 & 7) so i don't think i need to identify them via a 1 cable network?
Could i just use something like;

trisc.4 = 1
trisc.3=1
cell1 VAR PortC.4 ' One-wire data pin "cell1" on PortC.4
cell2 VAR PortC.3 ' One-wire data pin "cell2" on PortC.3
solenoid VAR PORTC.1 'solenoid contactor coil power

Cold_Bit VAR R_Temp.Bit11' Sign-Bit for +/- Temp. 1 = Below 0 deg C
Real_Cold CON 1 ' Define Real_Cold = 1
R_Temp VAR WORD ' RAW Temperature readings
TempCell1c VAR WORD ' Temp in deg C
TempCell2c VAR WORD ' Temp in deg C

start:
GOSUB Temp_1
GOSUB Temp_2
let tempcell1c = tempcell1c + 21
if tempcell1c > tempcell2c then
high solenoid
else
low solenoid
end if
let tempcell1c = tempcell1c - 21
pause 45000
goto start


Temp_1:
OWOUT cell1, 1, [$55,$28,$B1,$FE,$22,$00,$00,$00,$5D,$44]
OWIN cell1, 4, [Stat]' Check for still busy converting
IF Stat = 0 THEN W1' Still busy?, then loop
OWOUT cell1, 1,[$55,$28,$B1,$FE,$22,$00,$00,$00,$5D,$BE]
OWIN cell1, 2, [Temp.LOWBYTE,Temp.HIGHBYTE]' Read two bytes, then end communications
GOSUB Convert_Temp1

Convert_Temp1: ' +32.0 to +257 F
IF Cold_Bit = Real_Cold THEN Yikes ' If Cold_Bit = 1, it's below "0" deg C
Sign = "+"
Dummy = 625 * R_Temp ' Multiply to load internal registers with 32-bit value
Tempcell1c = DIV32 10 ' Use Div32 value to calculate precise deg C
Dummy = 1125 * R_Temp
ENDIF
RETURN
Temp_2:
OWOUT cell2, 1, [$55,$28,$B1,$FE,$22,$00,$00,$00,$5D,$44]
OWIN cell2, 4, [Stat]' Check for still busy converting
IF Stat = 0 THEN W1' Still busy?, then loop
OWOUT cell2, 1,[$55,$28,$B1,$FE,$22,$00,$00,$00,$5D,$BE]
OWIN cell2, 2, [Temp.LOWBYTE,Temp.HIGHBYTE]' Read two bytes, then end communications
GOSUB Convert_Temp2

Convert_Temp2: ' +32.0 to +257 F
IF Cold_Bit = Real_Cold THEN Yikes ' If Cold_Bit = 1, it's below "0" deg C
Sign = "+"
Dummy = 625 * R_Temp ' Multiply to load internal registers with 32-bit value
Tempcell2c = DIV32 10 ' Use Div32 value to calculate precise deg C
Dummy = 1125 * R_Temp
ENDIF
RETURN




Yikes: ' Display full range -C to -F conversion
Sign = "-" ' Display - symbol for negative temp
Dummy = 625 * ~R_Temp+1' Multiply to load internal registers with 32-bit value
Tempcell1c = DIV32 10 ' Use Div32 value to calculate precise deg C
Tempcell2c = DIV32 10 ' Use Div32 value to calculate precise deg C
ENDIF
RETURN