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Rene
11-14-2006, 08:58 AM
Hi,

When I write

Main:
· owin OWIN· 13, 1, [result]
· DEBUG DEC result, CR
· PAUSE 200
GOTO main

it just display "255" however the thermocouple junction is cold or hot,
What is wrong??

Rene

Chris Savage
11-14-2006, 10:50 PM
Rene,
·
·· Reading that device involves a bit more than just reading in a variable.· You must first send a command to read a register (there are more than one) and then get the data back.· Please see our example code for this device on our website.· Also note there is an error in the code you posted as you have OWIN twice.


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Chris Savage
Parallax Tech Support

Rene
11-15-2006, 01:29 AM
Chris,

Yes I wrote owin twice on this example, I did not made this mistake when trying my device. The thing is, I've downloaded the sample DS2760TC_DEMO.BPE from your website, but thoses examples are too big with too mutch developments like 3 kinds of thermocouple, and the conversion of the datas into farenheight or celsius degree, and a subroutine for "out of range" and so.. What I'm looking for at first is to simply to understand how to read the appropriate register and get the datas from it wit a simple example which will do only it, then, I will make more codes to convert it later specially for my application, but for now too mutch code in first only mean too much confusing.

Like to learn basically the command "serout", I do not need to write down 5 pages of commands with many differents applications to learn it, 2 or 3 lines of codes plus 2 or 3 variables are quite enought to do the job.

Thank you very mutch.
Rene

Chris Savage
11-15-2006, 01:41 AM
Rene,
·
·· As with anything you have to break it down.· There is a subroutine called to read the temperatures…If you go to that subroutine you can easily see what is being sent and what is received.· This is where you get the data you need.· There is also the datasheet for the part.· The DS2760 datasheet can be found at www.maxim-ic.com (http://www.maxim-ic.com/) and would also have the lists of registers and return information.· Using that you should be able to come up with a simple demo.· Take care.

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Chris Savage
Parallax Tech Support

Rene
11-15-2006, 01:54 AM
Chris,

Thank you very much for the fast reply, I will get the datasheet and look at. I forgot to say that when I've tryed the demo from parallax, it has worked as I heatedup the junction with a small pencil torch, It does displayed high temp until it started to display "out of range" all the time. I made some check at the thermocouple with my voltmeter and it still supply some milivolts when heating it up (up to 14mv. approx.), so, I do'nt know if the DS2760 became defective...

Thank you.

Rene

Chris Savage
11-15-2006, 02:58 AM
Rene,
·
·· Verify your connections to the thermocouple…Make sure the wires are inserted securely and into the correct holes (polarity matters).· Also make sure the twist at the end is still secure.· The code works, so if you’ve made no changes then it has to be something with the hardware connections.

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Chris Savage
Parallax Tech Support