Yamaha DTXpress/DTXplorer/DTXtreme

Okay, I REALLY don't know much about MIDI, but here's what I want to 
do: a member of my band owns a Yamaha MFC1 MIDI foot controler, and I 
want to hook it up to my DTXpress so that he can hit his pedal and 
trigger a voice or song from my DTXpress.  Is this possible with what 
we have, and how do we do this?