Extra switches now customizable from webconf

Hi @Zynthianers!

I just commited a new version that adds the possibility of assigning customized actions to the configured extra switches.

The extra switches can be connected to the AllInOne’s sw1 connector, to your custom MCP23017 build, or to the RBPi’s GPIO free pins.

You can access the new options from the webconf’s “Wiring Layout” section. This is the logical extension to this previous development:

The configuration allows to choose the type of action for every custom switch and the specific parameters depending on this type:

  • UI Action

    • Short Action
    • Bold Action
    • Long Action

    • CC Number

So … just update software and enjoy! :wink:

P.S. That’s now documented on our wiki:

Adding Extra Switches - ZynthianWiki


That sounds awesome! Can this be expanded to cover multiple MCP23017 devices as well?

Not currently. Only one MCP23017 is supported right now …

This is great. I’ve just added two sneaky little switches to my zynth.

I’ve tried using these as a midi button, and while I can assign its midi number to an engine’s parameter like sustain, pressing the switch doesn’t turn the parameter on and off. The log shows:


Does it need to send a NOTE_ON and NOTE_OFF instead of a CONTROL_CHANGE for it to work?

Like you, I’m just learning about all this stuff. It looks like your switch is mapped to control change 8, which under the general midi protocol is mapped to balance. Sustain/Damper is mapped to control change 64 (see link). Try that and perhaps it may work.

P.S. I like your wooden case!

1 Like

You’re right: not all midi CC numbers are the same. Thanks for the help. :relieved:

1 Like

Any chance of getting keyboard functions…?

Sorry @wyleu! I don’t understand what you mean with “keyboard funtions”, my friend …

Audio record functions are already implemented as CUIA, and ALL CUIA are available as:

  • OSC command
  • MIDI events (note-on events on the Master Channel)
  • Keyboard keys

It’s documented in the wiki:



Well it’s the traditional wyleu persuit of record audio and stop audio functions off GPIO presses…

Surely we need a full list of CUIA functions here, not a limited ( but very useful) sub selection…?

course if someone from the 60hz world could demonstrate accordingly . . . .:face_with_monocle:

… and that’s before we start talking about toggle actions …! :smiley:

1 Like

OK @wyleu ! I already understand what you mean. It’s done, my friend!! :wink:

Simply update and (perhaps) reboot …



You realise this means even more 12 string guitar creations …?


Ohhhh! Yesssss!!! I’m waiting for more of your audio sample, my friend!! This time, i would like a well structured piece, something like intro-A-A-B-A-C-C-end, about 2-3 mins, please!! :rofl:


Well I would upload one but I wonder if we have hit some limit somewhere as I’ve made several attempts to upload a 5.0 Mb ogg and it never seems to get beyond 1%…

A post was split to a new topic: Funny PedalBoxes for Zynthian (using extra switches!)

hi Zynthianers,
Is it possible to use the extra switches as a program change?
For example:
in a MOD-UI layer, assign a program change to each extra-switch, to recall the presets associated with the Sub Snapshots
Sw1 (Short-push) = Program Change 50
Sw2 (Short-push) = Program Change 51
Sw3 (Short-push) = Program Change 52
Sw4 (Short-push) = Program Change 53
… and also implement the management of multiple banks, for example:
Bank1 (PC50, PC51, PC52, PC53)
Bank2 (PC54, PC55, PC56, PC57)
Bank3 (PC58, etc etc …)
manageable with:
Sw1 (Bold-push) = Bank Down
Sw4 (Bold-push) = Bank Up

what do you think about?


Currently you can’t do this directly … but …

  • You can configure the switches as CC, let’s say:

    • CC#45
    • CC#46
    • CC#47
    • CC#48
  • And add a simple rule to the MIDI router, like this:

MAP CC#45:48 => PC#1:4


MAP CC#45,46,47,48 => PC#1,2,3,4

This should do the trick :wink:


1 Like

Good news! I’ve extended the custom switches and now you can configure other types of MIDI events.
This is the list of supported MIDI event types:

  • CC
  • Note On
  • Program Change

Simply update and enjoy!!


Thanks @jofemodo ,
great job congratulations :clap: :clap: :clap:

How do I get it working?
I ensured that my knob is working with a UI Action.
But neither a Note On nor a Program Change is displayed in the Midi Log under ZynMidiRouter Main when I short press the button.

And why don’t distinguish those three between short, bold, long?

And don’t we need a Note Off as well?
And a MIDI channel.
That way you can define buttons that are triggering samples and stop them.