[Coco] CoCo3: banking in ROM-Packs

John W. Linville linville at tuxdriver.com
Tue Apr 10 16:13:53 EDT 2018

On Tue, Apr 10, 2018 at 06:34:23PM +0200, Pere Serrat wrote:
> Hello,
> I haven't found info about one point related to the
> banking system in the, let's say, Super-Packs.
> Reading Greg Zumwalt's article "Breaking the 32K"
> I have found that writting a number (0-1-2-3) to
> $ff40 will map to $c000 one ROM bank, good!
> My question now is ...
> What about the last 512 bytes ($ffe0-$ffff)?
> Are they lost in every chunk of 16K?
> Or, is there any trick to access all of these bytes too?
> Thanks beforehand
> pere

The ROM addressing is still based on CTS*. The address decoding
in the CoCo knows nothing of the bank switching, so CTS* will still
be generated the same way.  Therefore each bank will have the same
hole at the end.

John W. Linville		Someday the world will need a hero, and you
linville at tuxdriver.com			might be all we have.  Be ready.

More information about the Coco mailing list