[Coco] coco I 4K contest

[Arthur Flexser]

On Thu, Jan 1, 2015 at 1:50 AM, Camillus Blockx <camillus.b.58 at gmail.com>
wrote:

> Then someome should make it clear what the limits are, d'nt you think?
> I do not have a coco I 4k, but a coco3, so I actually do not know what
> would work on a coco I, besides then not using extended, disk and/or super
> extended basic command and/or Functions.
>
> Not using any of those would mean no syntax errors on a CoCo 1 with Color
Basic.  However, the mere presence of Extended Basic causes a lot of memory
to be reserved for PMODE graphics, so knocking out Extended Basic is
required, by pulling the chip (if it is in a separate chip) or by using an
emulator or whatever.  Once upon a time, I had a program called BABBAS.BIN
that would allow you, using a CoCo 1/2 disk system, to selected Color Basic
or Extended Basic, after which the CoCo would cold start in that mode.
Probably would work equally well on a CoCo 3.  I don't suppose anyone has
it or has heard of it?  I don't think it was a commercial program.


> I also read a couple of times that the Poke command would be of non
> excistance in basic 1.0, but in my ROM hexdump I can see clearly that the
> command is there. If it is usable, that I can not test.
>
> I think this was an error in some Tandy documentation, perhaps based on a
preliminary spec for Color Basic.  Probably cooler heads at Microsoft
prevailed, thank god, so even the earliest CoCos had POKE.

The difference between Color Basic 1.0 and later versions of Color Basic
are pretty much negligible.  Mostly bug fixes and support for 64K chips,
and the removal of the DLOAD command on the CoCo 3.  The one noticeable
difference was that in Color Basic 1.1 (I think), they put in a fast break
key check, causing some programs to run noticeably faster on account of
Basic's having a break key check between statements. This was removed in
later versions because it caused some incompatibilities with software that
used the keyboard rollover table to check if a key was being held down.
Color Basic 1.1 did not update the rollover table when the key was released.

Art