Snap! I have one of those pedals too. I like the idea that it simply works like a USB keyboard. No need for drivers & you can use it to control any SW (…if you can remap the keys). I used it with Soundplant to trigger samples during a performance.
Raspberry Pi s don’t seem ideal for embedded electronics, the Zero is extra slow booting, and there is the complication of shutting down properly so as not to chance corrupting the SD card.
Tiny core Linux which runs completely in RAM, so there are no CD card cache files to worry about, speeds startup as well.
Here’s one kinda old article on PiCore, referencing version 9.0, it’s currently up to ver 13.0 (54Mb DL)
Arduino boards provide near instant startup , and have built in ADC for potentiometer inputs, some processors have built in HID, USB MIDI capability including the cheap pro Micro and the Teensy line.
A mechanism that allows Sooperlooper to be operated by footpedals would seem very useful, even if it involves qwerty keypresses generating MIDI signals to be passed on to the appropriate MIDI channel for sooperlooper.
If you check out this thread you will see that footpedal control is possible with the right pedal. I am investigating the option of adding MIDI CC as a CUIA which would allow you to bind keys to CC but this may not make it into testing / next stable.
[Edit] I have a PoC working in a development branch which allows configuration of keybinding to CC:
Value 1 sent when key pressed, nothing sent on key release
Value 1 sent when key pressed, value 2 sent when key released
Value 1 & value 2 toggled on each key press, nothing sent on key release
I think this covers most use cases. The main issue is that there is no linkage between the key state and the controlled parameter so at first boot or loading a new snapshot they could be out of sync resulting in the first press not toggling the state. (Only relevant for toggle.) This is based on some changed event handing in the dev branch that won’t be merged into testing until after the next stable release. I haven’t checked if it can be back-ported but the current development cycle kinda excludes this as it would delay development. But basically, it may be on its way…