[Coco] GIME behavior

[Robert Gault]

Mark Marlette wrote:
> Darren,
>
> I am going to disagree with you and clearly change my original position..
>
> Here is a snipet of code from one of our products, not released and this works.....
>
>           lda   $FF90	   ; get CoCo 3 INT0 register
>           ldb   MMUReg      ; and MMU bank register
>           pshs  d           ; save for later
>
> To read these registers, I believe you have to be in the correct mode.
>
> Regards,
>
> Mark
> Cloud-9

Mark,
I've never seen any evidence that anything in the range $FF90-$FF9F can be read except for 
$FF92 and $FF93. There is no Tandy software that reads these bytes and both OS-9 and 
NitrOS-9 are forced to store values sent to this area on the direct page.

The code snippet given will run but the data obtained by lda $FF90 will not be of any value.

Robert