How to find MIDI function on DGX 660

[onyaw]

I am using a bandmate's DGX 660 for band practice so i don't have to lug my keyboard there and I'm trying to use my Viscount MIDI expander interface to play Hammond B3 sounds using the keyboard. I acquired a MIDI to USB converter, attached both MIDI cables to the respective in and out of the converter and the Viscount and the USB between the converter and the Yamaha but i can't find the MIDI function in the DGX function menu - I went through what seemed like all the categories and there was nothing called MIDI. Did i miss it? Is there another way to get to the MIDI menu? And if i find it, what am I looking to set it at to get the MIDI to play? Is there a quick way to switch it back to Yamaha sounds, or must i go through those menu functions again? Last, if i find the MIDI menu is the process the same if i decide to instead use and iPAD and garage band or some other software? Thx for your guidance.