Hi Larry,

Not with the Micro for the simple reason that it is not on the market yet here in Europe. And due to poor health I have not done anything with my Korg PA80 and the PSR3000 either, but in the past I always hooked up my two keyboards ( whichever they were) in this way.

As regards you being puzzled about " de-activation ", let me try and explain from your point of view. PSR3000 + Korg Micro.

For starters like I said you hook up the audio, so korg audio out to Yamaha audio line in to beef up the sound a bit. ( not taking into account external amplification).
Right, once you get the Micro you initially will want to try out things without taking into account the Yamaha, that is APART FROM ITS KEYS. In other words you hook up (via MIDI) upper 1, upper 2, lower and accompaniment. To hook up upper 1 , upper 2 and lower you simply make them correspondent with the midi in channels on the Korg MIcro,
simple as can be. As to getting the correct response for the accompaniment you have to check out your manuals. I mean the idea is to hit the START button on the Korg and then play the chords on the Yammie. As to the uppers, you select the sounds and performances on the Korg but play them on the Yamaha......

Only when you have got that whole circus going and once you have familiarized yourself enough with the Korg to know what there is to like and not to like you can decide to DE-ACTIVE the upper 1 and upper 2 midi channels, or even the lower if you like BUT NOT THE ACC. CHANNEL. By doing so you retain a choice of accompaniment by playing the Yamaha depending on which keyboard you start with the start/stop button. But as you have disconnected the other midi links your PSR right hand will play the PSR sounds of your choice, and the KOrg righthand side the Korg sounds of your choice. In other words you can always have FOUR sounds at instant touch. And two different accompaniment depending on which keyboard yuo get going !!!!
Have you already got the Micro by the way ?

Good luck ,
John Smies