[Coco] NitrOS-9 ROM Pak ?

[Darren A]

On 3/29/09, Roger Taylor wrote:
>
> I thought Boisy's FAQ talks about using a 16K ROM (for a CoCo 1/2?).
> What about a 32K ROM.  I've never burned any to see if they map in at
> $8000 or $C000 in two banks.  If they map in at $8000, it's the same
> exact thing as desoldering the CoCo 3 BASIC ROM set chip if you can
> just map the ROM in right or copy it down into the underlying RAM.
>

The CoCo 1 and 2 don't have a 32K External ROM mode like the CoCo 3.
To get 32K ROM in a cartridge on those machines you need some extra
hardware in the cartridge, either to employ a banking scheme or to do
your own address decoding and utilize SLENB* to prevent the internal
ROMS from being selected.

Darren