[Coco] Color BASIC 1.1 / memory detection

jon bird news at onastick.clara.co.uk
Wed Feb 18 12:41:10 EST 2015





It's definately a 1.1 ROM, the number is stamped on the chip and to be
sure I pulled the Extended ROM and confirmed it comes up with 1.1.

I also did a quick sense check - POKEing some values above the 16K
threshold and they all appeared "stuck" at 255. Which suggests that the
SAM has been programmed up for a 16K memory fit.

Rgs,

Jon.

>
> Art, I have an F-board (chicklet keys) that has both CB & ECB 1.0. It was
> one of the 32k boards that was actually 64k. Oddly, it recognizes as 32k
> of ram and not as 16k.
>
>
> Bill Pierce
> "Today is a good day... I woke up" - Ritchie Havens
>
>
> My Music from the Tandy/Radio Shack Color Computer 2 & 3
> https://sites.google.com/site/dabarnstudio/
> Co-Contributor, Co-Editor for CocoPedia
> http://www.cocopedia.com/wiki/index.php/Main_Page
> E-Mail: ooogalapasooo at aol.com
>
>
>
>
> -----Original Message-----
> From: Arthur Flexser <flexser at fiu.edu>
> To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> Sent: Tue, Feb 17, 2015 6:49 pm
> Subject: Re: [Coco] Color BASIC 1.1 / memory detection
>
>
> Are you sure that your COLOR BASIC (not Extended Basic) is version 1.1?
> You cannot readily detect the Color Basic version with Extended Basic
> installed.  If in doubt, pull the Extended Basic chip and see what the
> startup message reports.  (Though I would think an F-board CoCo would
> indeed have Color Basic 1.1, not 1.0.)
>
> Art
>
> On Tue, Feb 17, 2015 at 5:14 PM, jon bird <news at onastick.clara.co.uk>
> wrote:
>
>> Hi,
>>
>> I have just recently resurrected my old Coco 1 (it's a 26-3004A variant)
>> and have been putting it back to an original (working) state (I had been
>> plugging various additional cards & even a Dragon ROM into it at some
>> point).
>>
>> The info I can find on this version of the CoCo was that it was shipped
>> with 16K RAM, Color BASIC. It had an Extended BASIC 1.1 ROM fitted many
>> years ago and as part of my various "upgrades", replaced the 16K RAM
>> chips
>> with 4164 DRAMs & also switched over the jumpers.
>>
>> What I am finding though is that having restored the original Color
>> BASIC
>> 1.1 ROM, it is only reporting a 16K memory fit. I'm pretty sure that
>> when I
>> had the Dragon ROM fitted, it could access the full 32K (and I'm also
>> fairly sure I had OS9 running on it as well which suggests the full 64K
>> is
>> accessible). So this seems to be a feature of the BASIC ROM.
>>
>> I did come across this article from the archive:
>>
>> http://coco.maltedmedia.narkive.com/2DM5LvJ2/color-basic-1-0-1-2-differen
>> ces
>>
>> which backs up some other information I found that the original 1.0 ROM
>> did not support >16K memory fit but that the 1.1 ROMs do.
>>
>> Can anyone shed some light on this behaviour?
>>
>> Cheers,
>>
>>
>> Jon.
>>
>> --
>> == jon bird - software engineer
>> == <reply to address _may_ be invalid, real mail below>
>> == <reduce rsi, stop using the shift key>
>> == posted as: news 'at' onastick 'dot' clara.co.uk
>>
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco
>>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
>
>
>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
>


== mailto:jon at onasticksoftware.co.uk - in real life jon bird
==  http://www.onasticksoftware.co.uk - stuff, on-a-stick
==   "men love women, women love children, children love hamsters"
==    <technology out of control>




More information about the Coco mailing list