[Coco] CoCo 3 POKEs to go to "CoCo 1/2" mode?

[Arthur Flexser]

No, there were a couple of things that got modified in the Microware CoCo 3 changes that were done to the ROMs, not patched in as RAM overlays.  The main thing was changing DLOAD in ROM to make it do a cold start.

Art
________________________________
From: Coco <coco-bounces at maltedmedia.com> on behalf of Allen Huffman via Coco <coco at maltedmedia.com>
Sent: Sunday, January 29, 2023 7:38 PM
To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
Cc: Allen Huffman <alsplace at pobox.com>
Subject: Re: [Coco] CoCo 3 POKEs to go to "CoCo 1/2" mode?

Note: This message originated from outside the FIU Faculty/Staff email system.


> On Jan 29, 2023, at 6:12 PM, Arthur Flexser via Coco <coco at maltedmedia.com> wrote:
>
> Sure, just do the poke to go to the ROM mode:  POKE &HFFDE,0.
>
> This doesn't quite restore the ROMs to the CoCo 1/2  mode.  You still won't have a DLOAD command.  But close.


I had been under the impression that the original two 8K ROMs for Color BASIC and Extended BASIC where untouched, and the additional ROM code just applied patches/overlays to them.

After a POKE &HFFDE,0 and then a POKE 113,0:EXEC 40999, it does reset back to the old Extended Color BASIC 1.1 screen (confirming there was no 1.2 used in the CoCo 3), but DLOAD causes a reset/crash which indicates it’s still pointed to reset code.

Time to check Unravelled...
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Allen Huffman - PO Box 7634 - Urbandale IA 50323 - 515-999-0227 (vmail/TXT only)
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