I believe the OutputCH simply sends the chord(s) from Biab to an external device (keyboard/vocal hardware). Yamaha uses XFMidi format for their chord recognition/generation on their keyboards.

FYI: If you are NOT a member of PSRTutorial site, you should sign up there. They have EVERYTHING covered for Yamaha Keyboardist's. You can find software there that will extract chord data from midi files etc. A great site. They will also have exact directions on how to add chords for their vocoders for each Yamaha Keyboard and operation.

PSR Tutorial

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