Modep issue (community)?

phil123456 · April 2, 2021, 9:41pm

Hi,

I can’t find the modep community
I want to address an issue, not sure this is the right place to do it

my problem is that my midi pedal can only mod one pedal at a time

quiet annoying since you might wanna modulate different parameters or disable one pedal while another one could receive the foot pedal CC values

thanks for helping me on this

Thethanx · April 3, 2021, 11:31pm

This is the Modep community. I’m still figuring things out myself, but I’d recommend starting by searching the forums for your answer? It would probably help to know what kind of midi controller your using, whether it’s connected via the DIN ports or USB, and what settings you’re running. It sounds like Patchbox is at least recognizing the controller for some things? Is everything sending CC?

You could try seeing if this post has any relevant information. This post also has some useful stuff to dig through.

The best way to go about it is to use the little magnifying glass while you’re in the “modep” section of the forum. If you type in “midi” it should give you all the midi topics specifically within the modep category.

phil123456 · April 4, 2021, 6:36am

it working perfectly fine, I removed the DIN connectors for ventilation

my issue is the modep software

once you assign “MIDI” to different controls, only one is taken into account

let’s say you have a multi band filter pedal, well I want to modulate all 3 bands with the same pedal

also you cannot select any midi channel and there is no “learn” capabilities AFAIK

Thethanx · April 4, 2021, 1:24pm

Okay, so to clarify: you can in fact select parameters across multiple pedals, the problem is that you want 1 “pedal” (I’m assuming you mean an expression pedal vs a footswitch) to control multiple parameters.

So ideally you want to say, be able to select a parameter somehow, and then the the means to control those parameters would be assigned to the expression pedals on your footswitch?

If this assumption is correct, the problem isn’t a modep one, your pedal will only be able to send one midi cc message at a time and what channel that is, whether its a note or CC, and whether it’s momentary or a hold depends on the controller. I know my controller has its own software that I use to assign these things.

As far as “selecting any midi channel goes” and a learn function, can you be more specific? As far as I can tell modep doesn’t have any midi channels that cant be used, and again, if you want to change what message your pedal is sending you do at via your controller, not modep.

What pedal are you using?

phil123456 · April 4, 2021, 6:08pm

at software level, there is no reason why a controller could not affect multiple parameters

also the selection like toggling a midi button “on/off” seems another limitation…I cant even indicate which CC is linked to what parameter so moding my pedal so it sends multiple control changes won’t fix the issue

another point is that modep allows for multiple controls to be “MIDI” linked…the midi standard has more than one single ON/OFF feature

fyi : I built my own pedal, based on an arduino that sends a CC, but that’s not the problem

phil123456 · April 4, 2021, 6:22pm

from the MOD documentation

If you want to assign any type of parameter to an actuator of a MIDI Controller connected to your MOD device you must select the “MIDI” tab, press save and interact with the desired actuator (for example: push the button or turn the knob).

https://wiki.moddevices.com/wiki/MOD_Web_GUI_User_Guide

well it’s not working for me…I should be able to link my pedal to as many controls I want

that’s the whole idea behind “MIDI Learn”…it’s note a 1::1 mapping… it’s 1::N or at least it should

Thethanx · April 5, 2021, 7:44pm

Ah yes I understand now. Sadly I do not know the answer to why current Midi mapping restricts control to one parameter per CC assignment, but Id also love to be able to map multiple things to 1 knob.

Based on the documentation, It clearly is possible using the actual MOD hardware knobs, so I assume there’s a reason that midi is more restricted, but I wouldn’t know why.

Hopefully one of the more experienced folk will chime in.

Giedrius · April 6, 2021, 8:01am

This is how it’s implemented for some reason in mod-host (this is a link to our fork of MOD Devices mod-host repository):

github.com

BlokasLabs/mod-host/blob/master/src/effects.c#L1716


{
    if (g_midi_cc_list[j].effect_id == ASSIGNMENT_NULL)
        break;
    if (g_midi_cc_list[j].effect_id == ASSIGNMENT_UNUSED)
        continue;

    // TODO: avoid race condition against effects_midi_unmap
    if (g_midi_cc_list[j].channel    == channel &&
        g_midi_cc_list[j].controller == controller)
    {
        handled = true;
        value = UpdateValueFromMidi(&g_midi_cc_list[j], mvalue, highres);

        postponed_event_list_data* const posteventptr = rtsafe_memory_pool_allocate_atomic(g_rtsafe_mem_pool);

        if (posteventptr)
        {
            posteventptr->event.type = POSTPONED_PARAM_SET;
            posteventptr->event.parameter.effect_id = g_midi_cc_list[j].effect_id;
            posteventptr->event.parameter.symbol    = g_midi_cc_list[j].symbol;
            posteventptr->event.parameter.value     = value;

It first goes through the list of MIDI mapped CC parameter changes, and in case it finds on to work with for the current message, it processes it and stops further handling like MIDI learning, which is just after this block.

I don’t know why it was made this way, maybe there’s some special case to avoid somewhere by not allowing multiple mappings of same CC, but we can find that out! It’s easy to workaround, in just 13 steps:

git clone https://github.com/BlokasLabs/mod-host
cd mod-host
nano src/effects.c (or use any other editor at your convenience, it’s a huge file!)
Comment out line 1716, so it looks like this: //handled = true;
Comment out line 1735, so it looks like this: //break;
Save & exit.
Install build dependencies: sudo apt install libreadline-dev liblilv-dev
Build: make
Install: sudo make install
Make a local copy of modep-mod-host.service, so it overrides the default one: sudo cp /usr/lib/systemd/system/modep-mod-host.service /etc/systemd/system/
Edit it to point it to the locally built mod-host binary: nano /etc/systemd/system/modep-mod-host.service, change:
```
ExecStart=/usr/bin/mod-host -p 5555 -f 5556
```
to:
```
ExecStart=/usr/local/bin/mod-host -p 5555 -f 5556
```
Save & exit

Reload and restart systemd services:

sudo systemctl stop jack modep-mod-host modep-mod-ui
sudo systemctl daemon-reload
sudo systemctl start jack
sudo systemctl start modep-mod-host
sudo systemctl start modep-mod-ui

Now you should be able to map the same MIDI controller to multiple parameters.

phil123456 · April 6, 2021, 9:00am

dude, I can’t wait to try this out

would I then submit a PR ? is anyone interested in this ?

Giedrius · April 6, 2021, 10:51am

I’d suggest just giving it a try for a little while and check if you get any issues because of the change.

Then if it’s all fine, float the idea on the MOD Devices forum and see what the developers say. From the code history, the general structure of that part seems to haven’t changed much since original version, so maybe there is no technical reason to prevent one control to many controls mappings.

phil123456 · April 6, 2021, 2:02pm

what is the difference between modep and mod device ?
what does ep mean btw ?

Giedrius · April 6, 2021, 10:03pm

MOD Emulator [for Raspberry] Pi

MODEP is just a slightly customized variation of the MOD open source software, stuff like having hardware specific features that won’t work on a plain Pi disabled, and is ready to install and run on Raspberry Pi’s.