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Author Topic: PIC-WEB thermistor code - hi res  (Read 3821 times)

eagleeye

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PIC-WEB thermistor code - hi res
« on: December 02, 2012, 05:07:49 PM »
Hi
 I am not familar with the thermistor on the pic-web.
Can anyone share code that can get more resolution out of
this thermistor?

Regds
Allan

LubOlimex

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Re: PIC-WEB thermistor code - hi res
« Reply #1 on: December 03, 2012, 09:05:21 AM »
Hello Allan,

We have used the standard B equation found here: http://en.wikipedia.org/wiki/Thermistor. The only parameter unknown is the temperature. Over the course of time we have used different thermistors with PIC-WEB each with a bit different B. The last revision use thermistors with B=4000 but previous ones have used thermistors with B=3900 and B=4200.

Best regards,
Lub/OLIMEX
Technical support and documentation manager at Olimex

eagleeye

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Re: PIC-WEB thermistor code - hi res
« Reply #2 on: December 16, 2012, 04:17:43 PM »
Hi Ok, Just to clarify.. I looked at the thermistor code in stack 5.42, the code implements
a very accurate sampling as opposed to Stack 5.31 code.

However the temperature variable should be a FLOAT and not an int.
The developer must also provide their own ftoa function so that
the temperature has decimal points shown.

Allan

LubOlimex

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Re: PIC-WEB thermistor code - hi res
« Reply #3 on: December 17, 2012, 01:02:27 PM »
Hey eagleeye,

Thank you for clarifying.

The example provided doesn't aim at accuracy. Every developer (who agreed with the license agreement) is free to modify the demo programs to fit his needs.

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Lub/OLIMEX
Technical support and documentation manager at Olimex

eagleeye

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Re: PIC-WEB thermistor code - hi res
« Reply #4 on: December 18, 2012, 03:51:24 AM »
Hey eagleeye,

Thank you for clarifying.

The example provided doesn't aim at accuracy. Every developer (who agreed with the license agreement) is free to modify the demo programs to fit his needs.

Best regards,
Lub/OLIMEX

Sure, not everyone are experts, so I am looking to Olimex to lead the way for the best
way to utilize their boards. The new code in  Stack 5.42 is very comprehensive.
This is excellent.

ALlan



LubOlimex

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Re: PIC-WEB thermistor code - hi res
« Reply #5 on: December 18, 2012, 04:07:55 PM »
Thank you Eagle,

Please check the updated manual of PIC-WEB - it features new first steps section updated to this date:
https://www.olimex.com/Products/PIC/Development/PIC-WEB/resources/PIC-WEB-C.pdf

Best regards,
Lub/OLIMEX
Technical support and documentation manager at Olimex