[sdiy] Xpander

[Michael Zacherl]

> On 18.10.2020, at 05:09, Brian Willoughby <brianw at audiobanshee.com> wrote:

> I believe that the main CPU writes directly into the memory space of the voice CPU. i.e. there are no "MIDI" messages exchanged with the voice boards, but direct memory modification. 

I think I read, the main cpu issues a halt-request to the voice board, which causes the voice cpu to set its bus-lines into high-Z mode, IIRC.
Which would fit the picture you describe. 
m.