[Coco] NitrOS-9 and the MPI

Gene Heskett gheskett at wdtv.com
Sat Nov 8 06:05:01 EST 2014


On Saturday 08 November 2014 01:54:00 Darren A did opine
And Gene did reply:
> Does anyone know if NitrOS-9 provides any kind of support for the MPI?
> If a driver is associated with a cartridge that uses SCS* for address
> decoding, is it completely the responsibility of the driver to make
> sure the correct MPI slot is activated?
> 
> Since the floppy controllers use SCS* for decoding I tried looking
> through the rb1773 code, but didn't find any evidence to indicate that
> it takes the MPI into consideration.
> 
> Darren

It is generally in the driver Darren. An innocent looking lda 
someplace,pcr, followed by an sta >$FF7F or similar is how it is generally 
done.

Note however that due to those of us who have strapped all the card 
sockets pin 8's together in order to bypass the IRQ steering logic in the 
MPI, it becomes easier because one nibble of such a write is then ignored.
And you never again miss an incoming byte from anyplace in the MPI.

Cheers, Gene Heskett
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