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Pico ADC

Posted: Thu Oct 21, 2021 12:31 pm
by p.erasmus
Hi Team

Please help ;)
for the life of me I canot get the adc on the PICO to work and searching the wiki I find zero info on the PICO ,Is there any wiki pages on the Pico ?

It seems also I cannot set the conversion speed in the properties ,If I try to use the set properties macro in code then I need to give a number for conversion speed as per ref list where is this list ?
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UART_ADC.fcfx
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Thanks a million for helping out

Re: Pico ADC

Posted: Thu Oct 21, 2021 12:52 pm
by LeighM
Hi,
The Pico version does not need (or use) any of those parameters.
However, you do need to call (once before start of the loop) the RawEnable()

Re: Pico ADC

Posted: Thu Oct 21, 2021 12:57 pm
by p.erasmus
leigh
Thanks a million will try however is there something about all of this in the wiki ,I really do find zero info in my wiki :D

Re: Pico ADC

Posted: Thu Oct 21, 2021 1:13 pm
by p.erasmus
Hi

I have done as you recommended however the ADC0 always show 800 to 970 counts even with no voltage applied to GIO26 I can try any of tha ADC's the result is the same
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Re: Pico ADC

Posted: Thu Oct 21, 2021 1:34 pm
by LeighM
What did RawSample() give?
What do you mean by "no voltage applied"?
Have you got a load resistor, or a fairly low impedance supply attached?

Re: Pico ADC

Posted: Thu Oct 21, 2021 1:46 pm
by p.erasmus
The sample give alway these numbers as shown in the terminal window

If I apply 1.0V at the ADC0 it still show the same number and I can vary it from 1V to 3,3V and the numbers stay the same
What do you mean by "no voltage applied"?
I am saying the numbers show as in the terminal even if 0V on the ADC0 pin

Yes I have low impedance source my input is buffered with an OPAMP circuit which I am using for at least 10 years on PIC ,ARDUINO and now latly on ESP32. all ways worked on all of them .

I do not know what can the issue be :oops:

Re: Pico ADC

Posted: Thu Oct 21, 2021 2:16 pm
by LeighM
hmm, strange, it worked when I originally wrote and tested it,
just dug out my test from May and that just used GetInt() in a loop,
no "Enable" required in that case.
Could you try same?
Thanks
Leigh

Re: Pico ADC

Posted: Thu Oct 21, 2021 3:12 pm
by p.erasmus
Leigh,

Thank I will try this in the evening and will report Thanks again for your help. :D

Re: Pico ADC

Posted: Thu Oct 21, 2021 3:49 pm
by p.erasmus
Hi Leigh.

Thank you for your help that worked and now after that the RawInt() is also working .
Just one of those things :D :D :D :D

Thanks a million