Keith McMillen 12 step midi pedal with s970

[g9j]

I bought this particular pedal to trigger chord sequences with styles.
How do i connect this pedal to  the s970? Do i need the interface
That they sell - the Midi expander. Honestly,
I want to trigger chord sequences while i play a guitar solo.
Treat me as a newbie, because i dont know the setting to be made on the keyboard for
The pedal and keyboard to communicate

[EileenL]

Why not record your backing first and then play along with them or you can even use midi files.
  The only provision you have is to connect two effects pedals to the keyboard.