Audiofront

I am aware the MIDI Expression can detect a double footswitch configuration, and the few that I have found are stupidly expensive, so I am looking to make my own.
Does anyone know how they are wired for the software to detect it?

There are wiring diagrams in the back of the manual.

Thanks Rob.
I have decided to buy a Digitech FS3X 3-button pedal.
The first two buttons work as expected, the third fires both #1 and #2 together.
Obviously MIDI-wise there is a slight delay between events.

I am primarily using this with Gig Performer, so I am working on a workaround script to detect close MIDI events on those CC's as button #3
It might be a nice addition in future firmware upgrades to provide a means of detecting this automatically.

It's not an issue with the electronics, it's an issue with the device's memory structure. It's possible to do, but it would be a huge and bug prone undertaking.