[Coco] MPI (was Re: A new idea for a CoCoSDC expander)

[Darren A]

On Wed, Oct 15, 2014 at 11:46 AM, tim lindner wrote:

>
> The address for the software switch is $ff7f. Bits 0 and 1 selected
> SCS slot. Bits 5 and 4 selecte CTS (and CART) slot.
>
> Write Only.



The register at FF7F is Read/Write.

Unlike a real MPI, Ton Gunnison's design fails to activate the data bus
transceiver on reads (at any address) when the SLENB* signal is asserted.

Darren