If you’d like to use MIDI CC4, you need to go to SETUP > EXTERNAL > EXT#1 > SOURCE and set that to “foot con”. The MIDI CCs are listed on page 45 here: https://s3.amazonaws.com/com.eventide.downloads/Product+Manuals/EclipseUserManual.pdf
Once you’e confirmed that is setup correctly, you’ll need your MIDI controller to send CC4 with a value of 64 or higher, only when it is pressed. The CC should toggle from 0, to 127, back to 0 when you press the switch. This is standard behavior for MIDI toggle switches. I’d suggest using a MIDI monitor with your controller to confirm it is sending the message correctly.
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