Control Chain - MODEP

Does anyone knows if it is possible to use MODEP with any control chain device from MOD?
https://wiki.moddevices.com/wiki/Control_Chain
As I’ve seen it’s possible to create your own devices with this shield for Arduino https://www.moddevices.com/products/arduino-shield which seems interesting for a footswitch or to change pedals’ parameters.
This would be an interesting accessory to MODEP, for instance: https://wiki.moddevices.com/wiki/Arduino_LiquidCrystal_tutorial
Let’s see if this is something compatible with Raspberry and MODEP.
Thanks!

Most likely this Arduino shield won’t work with Raspberry Pi - the devices seem to be powered via ‘Power over Ethernet’, Raspberry Pi requires an additional HAT for that, or you’d have to come up with some solution to power it up.

It also looks like the Control Chain library can work as a USB COM serial device, these devices could work. We have not tested this functionality in MODEP, so we can’t say whether it’s all set up already, or whether some updates and config changes are necessary in MODEP.

ok @Giedrius! Powering the device won’t be difficult without using POE as Arduino can be powered in many different ways (I guess that would work).
I will do some research with MODEP first and will post if I come with any good conclusion about the whole thing. Thanks!

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@marccobe sorry for resurrecting, but I guess you might still be interested.

I am trying to get this working on a RPI3 with pisound, however I am testing way too many things to know exactly what I am doing wrong. However, I will still log my process here for anyone interested or anyone willing to help in this.

There are two sides in this, there is the arduino side and the raspberry pi side, and -at least for me- both have never been tested so I might be wasting my time.
Arduino Side
I am using a teensy 4.1 with a TFT screen and a pushable encoder for testing.
So far I have modified the arduino-cc-library to support Control Chain over the USB Serial. If my modification is correct I cannot say, but to my eyes it looks like it is working - handshaking works correctly and pings happen in time.

RPI Side
Here comes the interesting part. To my understanding, the modep-mod-host is compiled without the cc_client library and the cc_master is not packaged at all by Blokas.
To remedy this, I cloned the cc-master repo, compiled and installed it in my PI.
I also created a systemctl service to launch this on boot and changed the default modep-mod-* services to wait for it before launching.
Afterwards I recompiled/repackaged modep-mod-host in my PI in order to link to the cc_client and installed the generated artifacts.

After all this process, I would expect this whole thing to work, but for some weird reason it doesn’t! I get popup notifications on the web-ui when I plugin my teensy, but I cannot see the Control Chain button when editing the plugins.

If someone with development experience can help, I would gladly provide further info and follow up with code in github for collaboration, but so far I am not pushing stuff anywhere because they are not working…

Well, on the positive side, I have validated that the Teensy side works properly.
I used the cc_client.py and crudely validated that if properly assigned, the value updates work correctly on the teensy in both directions of communication.

What is left is to fix the RPI side with the mod-host and mod-ui properly responding and assigning functionality on the Control Chain device.

I found out that Control Chain has been forcefully disabled by the MODEP developers:


I am now reverting their changes and hopefully I will have this working soon!