Connect the FS-5U to the Xpdl-input. (I have my polarityswitch to the right, but I don´t know if it matters.)
EFX MkIII:
Enter Editmode (hold Mode-switch until it reads PC.1)
Press PS-1-switch until it reads ESW (it almost looks like ESu with a line over the u).
Press PS-3-switch and change the controllernumber to (in my example) 12.
Press Mode-switch again to step out of editmode.
Eventide:
Enter System-mode
MIDI
RCV CTL
Change the left field from BYP to TAP
Push the right footswitch (choosing the right field) and turn the decoder to example C12. I personally choose this because often the CC-numbers up to 11 are standard for certain parameters.
Just check that the two units speak with eachother on the same channel…
Gerangiro