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Member
james_t_dk_home
Posts: 11
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1-wire temperature in LabView

Hi

I'm trying to write a driver for 1-wire (www.ibutton.com) to LabView.
For starters I didn't have any contact at all! But now I can read the uniqe ID from temperature sensors connected to both my USB and my RS232 adapter.

And then the fun stops.
I can not communicate with the temperature chips (DS1920 & DS1822) I can't even get the IsTemperatureContainer to reply with a true.

Does anyone have the time to review my code and maybe suggest changes?

You can request a free samlpe at www.ibutton.com I recomend getting a DS1920 and a DS9490B for testing purposes, order sampels from here: http://www.maxim-ic.com/samplescart.cfm

You need to have the OWAPI installed (http://db.maxim-ic.com/ibutton/example/)......
But if you know a better way or can use one of the other API's please let me know. I just need to read the temperature, how it's done is not important (except it has to be done with LabView).

Please help, this is very urgent.

J;-)
Member
briancam
Posts: 22
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Re: 1-wire temperature in LabView

I am trying to do the same with DS18S20.
I plan on using a DS2480 to convert 1-Wire to RS232.
 

I need to use

simple ASCII commands which I plan to write a Automated test program in LabVIEW.

Should I get

HA7E is a RS232 to 1-Wire interface? or can HA2 - RS232 1-Wire Host Adapter do the same function?

I have a DS1820 I need to use the CRC algorithm Specified by Dallas and

perform the following Tests:

Read 64 bit ROM of DS18S20, Resultant byte from CRC algorithm must match

the eight (last) byte of ROM.

Read 72 bit Scratchpad of DS18S20, Resultant byte from CRC algorithm must

match the ninth (last) byte of Scratchpad.

Next, I have to:

TH byte is downloaded from E2 memory to scratchpad. TH byte in scratchpad

is read.

TL byte is downloaded from E2 memory to scratchpad. TL byte in scratchpad

is read.

Finally, I need to read Temperature, which is read via data in

bytes 0,1,6 & 7 of the Scratchpad.

Can I accomplish this by MANUALLY typing the commands over the RS-232 Comm

Port from a PC?????

 

If anyone has any comments or am I taking the correct path? your help appreciated.

Thanks