[Coco] 64 K upgrade for COCO 1 gives ?OM ERROR

[Arthur Flexser]

The ?OM ERROR sounds like the machine is sensing that it has only 4K of
RAM.  A test would be that certain very simple commands DON'T give the
error.  If PRINT 5 works correctly, then that"s definitely what the problem
is.  Sounds like a misplaced jumper.

Art

On Sat, May 2, 2020 at 6:01 PM John E. Malmberg <wb8tyw at qsl.net> wrote:

> I have a COCO 1 later grey case with the non-chicklet keyboard.
>
> It was has a 16K memory badge.
>
> While the computer had 16 K memory in it, I was able to verify that it
> had BASIC 1.1 ROM in addition to the ECB ROM.
>
> I tried to put 64 K using 2164 memory chips.
>
> The circuit board had 4 jumpers to move to go from 16 K to 32 K, which I
> moved to the correct locations.
>
> The circuit board has a jumper set labeled high / low.
>
> The computer boots, displays the sign-on for Extended Color Basic 1.0.
>
> It reports ?OM ERROR for any command given.
>
> Any ideas?
>
> Regards,
> -John
>
>
>
>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
>