[Coco] Proof-of-concept to make 16KB HDB-DOS ROMs seamlessly

[Tormod Volden]

On Fri, Jan 31, 2014 at 3:50 AM, Juan Castro wrote:

> > I replicated the "two byte ASCII signature" scheme to allow for playing
> > with those unused top 8KB of ROM space. The example just puts an
> > exclamation point at the top right of the screen, but you can do
> anything.
> > Tell me what you think.

Hi Juan,

Great to see some new ideas for these ROMs.

> Exactly. But I did have to make a few changes to the current 8K ROMs (see
> the patch):
>
> - Insert the E000 signature test code;

Why do you have to check run-time for the high ROM? What is the use
case? Will this 16K ROM replace an original 8K ROM, or do you have two
ROM slots so that the lower one is fixed and it has to check if you
have a high ROM or not in another slot?

> - Change a BSR to JSR because a routine became too far away;
> - Shorten some messages to make way for the two things above.

I think it is a bit unfortunate to change error messages, because
documentation will also have to be updated.

Isn't there an unused block of 39's somewhere?

> On Fri, Jan 31, 2014 at 12:47 AM, Bill Pierce wrote:
>> I would commit it as a new rom. Leave the old "as is".'
>> Create an "hdbdos_16k.rom" or something.  This way, "just in case"

I agree, I would leave the default ROM as-is for now, contrary to what
your patch does.

>>
>> Boisy, Tormod... can I commit this?

IMO there is no rush to commit this to the repo. If this is a proof of
concept, you may want to play around with it and polish it before you
commit anything. It is not like we have dozens of people working on
HDBDOS at the moment so that a patch will go stale too soon :) Anyone
interested in trying it out can pick the patch from the mailing list.

>> > (This is a patch for the current source in Toolshed's Mercurial.)
>> >
>> > https://dl.dropboxusercontent.com/u/15643089/hdbdos-16krom.patch

In general it would be nice to have the patch included in the mail
message so that people can review and comment in-line using their mail
client. At least for me :)

Cheers,
Tormod