[Coco] POKEs and PEEKs in NitrOS-9?

[Robert Gault]

Bill wrote:
> Recently, while "goofing around" in an attempt to re-learn some of what I
> knew about my beloved Coco 3 (512k), I discovered that with 2 disk
> controllers in the MPI, while using RSDos, I could access any slot simply by
> using POKE &HFF7F,X. (X being 0 for slot 1, 17 for slot 2, 34 for slot 3,
> and 51 for slot 4.) I have written a test program, saved it to the drive
> controlled by the controller in slot 4, did the POKE for slot 3 (34) and
> saved it on the drive controlled by the controller in that slot. Works
> great, and I plan to investigate further.
>
> Now, here's my question: Can this same thing be done from NitrOS-9? Can
> POKEs and PEEKs even be used in NitrOS-9?
>
> Thanks
>
>
>
>

Not in the Disk Basic sense. There are some drivers that keep track of the MPI 
byte at $FF7F, change it as needed, and restore it after the requested command 
is finished.
Currently the floppy disk driver does not change $FF7F. You could change the 
source code for rb1773 so that it used a byte in the descriptor to indicate the 
required MPI slot. Then rb1773 could handle up to 16 floppies where say /d0-/d3 
were slot4, /d4-/7 were slot3, etc.

I don't see much point in doing that since few users would have more than one 
disk controller pack in an MPI.

Robert