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[RETRO Innovations]

On 1/4/2017 12:04 PM, Zippster wrote:
> I don’t think it’s particularly dangerous, but without the arbitration of
> the bus via the *CTS and *SCS signals as provided by an MPI, which
> carts would work together would be very limited.
>
> Not sure what if any arbitration is provided by the Glenside.
>
> Communications errors are very likely without buffering too, as I found
> out during developing the mini-MPI.
>
> Y-cables are probably ok for some things, for instance I imagine an Orc90
> and a floppy controller would work ok together.  They’re just of limited utility.
I echo these statements.  Except for essentially the CTS line, carts 
that reside above $ff5f are on a "buffered Y-cable" when they are in the 
MPI.

CTS gting makes a bit of difference there, so it's a win for the MPI, 
but the fact that the SCS space does not extend from $ff40-$ff7f limits 
the value of the MPI as well, buffered or otherwise.

Jim