[Coco] Conversion utility for Program Pak Images

Ron Klein ron at kdomain.org
Tue Feb 14 10:59:58 EST 2017


Hi John,

I may have misunderstood an older email comment from Robert Gault.  You can
see his comments toward the bottom of the post.  I was looking for
information prior to my posting and came across this...

Robert Gault <robert.gault at att.net>
1/26/16
to CoCoList
OK, after writing an ml routine to print data to the screen I can report
what a Coco3 sees in the external ROM with 16k / 16k internal external and
32k external.

The most reasonable way to present this is that the 32k ROM always exists
from $8000-$FF00 and when the Coco3 is in standard 16k internal 16k
external mode, it sees the second half of the external ROM.
So my program when using 16k/16k saw the Extended Basic ROM at $8000 and
the second half of the cart ROM at $C000. When the program set 32k
external, then it saw the first half of the external ROM at $8000 and the
same data (second half ROM) at $C000.
Can I prove that a ROM reader would see the same thing? No I can't, but I
expect it would. It makes sense because it is the only way a 32k ROM would
not get lost when switching from 16k/16k to 32k external.

And then how does this relate to .ccc files? These files do NOT present the
ROM as seen by a Coco3. The halves are reversed with the second half
preceding the first!
This makes no sense to me but someone must have decided that one of the
emulators JVC, MESS, or VCC could handle a 32k ROM cart more easily in this
fashion. That format then became the standard for .ccc files regardless if
it was reasonable.

On Tue, Feb 14, 2017 at 9:36 AM, John W. Linville <linville at tuxdriver.com>
wrote:

> On Tue, Feb 14, 2017 at 07:01:48AM -0600, Ron Klein wrote:
> > Hello,
> >
> > Does anyone know of a way to convert Program Pak images (*.ccc) to a
> > standard ROM file?  I heard the *.ccc format is mainly designed for
> > emulator use and not something that can be burned (or flashed).
> >
> > Thanks!
> >
> > -Ron
>
> AFAIK, the *.ccc format is just a flat binary -- the same as what
> you would burn into an EPROM.
>
> If you have other documentation, I would love to see it!
>
> John
> --
> John W. Linville                Someday the world will need a hero, and you
> linville at tuxdriver.com                  might be all we have.  Be ready.
>
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