AIO output signal controlled with python not stable

Moderator: RevPiModIO

Post Reply
Mattia Enapter
Posts: 2
Joined: 09 Aug 2021, 14:42

AIO output signal controlled with python not stable

Post by Mattia Enapter »

Hello, I'm new to forums, i hope my request is not appropriate and that someone can help me.

I'm actually using a rev pi core 3+ with 2 AIO modules. I'm trying to control the output signal (setted 0-10V) of the AIO modules with some python code. I normally use this command line to output the signal:

rpi.io.OutputValue_1.value=10000
time.sleep(1)

The problem that i have is that the output signal doesn't reach the desired 10V and it also present heavy oscillations. (3V->6V)

However, the problem doesn't persist if i set the standard value of the desired output at 10V from the https chrome page. Can you help me understanding why this happens? What other informations do you need? Thank you very much,

Best Regards
mattia
User avatar
dirk
KUNBUS
Posts: 2095
Joined: 15 Dec 2016, 13:19

Re: AIO output signal controlled with python not stable

Post by dirk »

Hello mattia,I have moved your post to this board because here the developers of RevPiModIO Library can assist you here competently.

One idea I have is to check if you have several instances of RevPiModIO running in parallel. Then there are competing accesses and the values jump as you have described.

Just try the following: End all Python processes e.g. with "ps ax | grep python" and then "sudo kill [pid]".
Then set the output with: "piTest -w OutputValue_1, 1000 "
Check if the value is present at the output.
Mattia Enapter
Posts: 2
Joined: 09 Aug 2021, 14:42

Re: AIO output signal controlled with python not stable

Post by Mattia Enapter »

Issue Resolved! Thank you very much for your celerity! You are doing a really good job here!

Best regards and Thank you again!
User avatar
dirk
KUNBUS
Posts: 2095
Joined: 15 Dec 2016, 13:19

Re: AIO output signal controlled with python not stable

Post by dirk »

Hi you're welcome thank you for your positive feedback.
Post Reply