Hi!

I'm just getting started and having some trouble with the analog inputs. I've scoured the forum and documentation, but I think it's time to ask for help.

All the analog inputs work perfectly with a potentiometer when I run scope-analog.cpp (from the examples folder) with just the Beaglebone Black + Bela Cape. As soon as I add a FACE in between, the analog inputs just remain a constant very high reading that is not affected by the potentiometer.

The IDE automatically recognises that I have "CTAG FACE + Bela". I tried booting instead from the pre-flashed SD card that I purchased as well, but the problem persists.

I would appreciate any help with this.

I'll need to have a look, that setup is not tested often. The latest significant changes in a place that could break things were done in November. Can you try updating your board from this zip archive from before those changes were made? https://github.com/BelaPlatform/Bela/archive/e06cdb266575cf302dc32b8390012d83f37cc087.zip

See updating instructions here https://learn.bela.io/using-bela/bela-techniques/updating-bela/#updating-to-an-experimental-release , but use the zip file linked above instead of the suggested one(s).

Hi Giulio,

Thank you for your quick reply. Unfortunately the problem persists.

Assuming I set up the book from flash correctly, I'm booting from an SD card. I first tried updating to the .zip version you shared from the IDE, but then reflashed my SD card with an earlier image. This is in the IDE as below:

Image:
v0.3.8g, 28 June 2022

Core code:
We could not determine the last time your core code was updated
Git desc: '83a6791b'

can you confirm what Bela cape you have? The revision number will be written on the top, something like Rev B5 or Rev C2

now the analog inputs don't even work with just Bela cape and Beaglebone Black

    lstrauss now the analog inputs don't even work with just Bela cape and Beaglebone Black

    yes, that's because of the downgrade of the image. Rev C3 really needs the latest image and core code. I'll look into your problem in the next few weeks days.

      5 days later

      Hi Giulio, out of interest, would it have been a simpler strategy to use CTAG FACE with a multiplexer on top for interactivity?

      No, the multiplexer also requires the bela cape.i had a look yesterday but couldn't fix it quickly. I'll spend more time on it today and I'll get to a solution

      Thank you so much! This works perfectly now with C++ so I know I'm getting analog in.

      It doesn't seem to be working with PD though. I am trying to log to scope from PD and getting nothing. I have changed [adc~ 3 4] to [adc~ 9 10] in the oscilloscope.pd example patch.

      I've played a bit more now and found another problem: all the analog inputs on the C++ side seem to be mapped to the A0 pin.

      Sorry to hear that. I am travelling now and no longer have a CTAG with me, but I'll try to sort something out tomorrow.

      Same problem here.

      Just unpacked and tested the analog-ins of the Bela cape (rev C3, 02/23) that is sitting on top of a CTAG FACE with purchased SD but getting no input on Pd's "adc~ 9-...".

      Do you have any update on this issue?

      I just got back to a place with a CTAG so I can have a look. Sorry, last week was madness.

      • bvk likes this.

      Hi Giulio, anything I can help with? It’s a blocking issue here and not sure how to investigate..

      A workaround is to run with 4 analog channels instead of 8. That seems to work. I am now looking into why the 8-channel version doesn't work.

      actually it seems that it's pretty intermittent the behaviour. Once every 2 or 3 runs , it will run OK with 8 channels, but sometimes it won't.