Dedicated GUI + controller using USART/I2C or SPI ?

[marcelgln]

I have to admit I am new to Mindexed, tried it once on an RPI and I was surprised it did work nicely without much effort. I like to build one as a rackmount synth, but like to have a bit more control than a rotary and a char LCD. I have seen quite some discussions from people who tried (or want) the same.

Frankly speaking, I do not think it is a good idea to attach an extensive display and UI to the Minidexed directly. The code is hightly optimized and it is easy to get into performance issues, which might affect the sound. I like separation of concerns, so my preference would be Mindexed with Midi/audio interface and a dedicated controller with displays, keys and rotaries (and maybe options to save/restore of patches)

Since the Minidexed already exists for some time, I wonder of someone else did this already ? If not, what are the options, is there a SPI interface or something alike to control all parameters ?

Any suggestions/tipw are welcome.

[probonopd]

Hi. It always depends on what you want to do, but at some point a Ljnux system with a full blown GUI application (e.g., made with JUCE) and/or VST3 becomes more practical (and can run e.g., on a Raspberry Pi 4 or 5). I have an experimental app and VST3 that is very similar to MiniDexed: https://github.com/probonopd/Synth_Dexed/releases/download/continuous/FMRack-ubuntu-22.04-arm.zip (works e.g., on Raspberry Pi OS; the VST3 e.g., can be used in REAPER).

[penfold42]

Since the Minidexed already exists for some time, I wonder of someone else did this already ? If not, what are the options, is there a SPI interface or something alike to control all parameters ?

Any suggestions/tipw are welcome.

Does minidexed support everything you'd want controlled over MIDI ?
If so, you could have a separate UI box connected over USB or UART and just use MIDI as the comms protocol.

We could possibly add MIDI over SPI if the uart and midi ports are occupied.

[probonopd]

Does minidexed support everything you'd want controlled over MIDI ?

Most things but not all. And you'd have to send many sysex which might slow things down.
There is a PR (not merged yet) which would make all parameters controllable and allow to send everything in one go:

#915

Please check whether this would allow you to do everything you'd like to do.