[Coco] CoCoNet status

[Art Flexser]

The only reason to check if it's a CoCo 3 would be so that you know NOT to
switch it back to RAM mode if it's a CoCo 1/2.  Perhaps a better approach than
checking at initialization whether it's a CoCo 3 would be to have the calling
routine check whether you're currently in ROM mode or RAM mode, and have it
restore that on exit, which should work on any CoCo.  (That's what Ext. ADOS-3
actually does.  I have a subroutine that does the actual calling that takes the
address in the upper ROM as an argument and which performs the necessary
housekeeping chores necessary to restore the initial state on exit.)

Art

On Sun, 7 Dec 2008, Roger Taylor wrote:

> At 05:55 AM 12/7/2008, you wrote:
> >On Sat, 6 Dec 2008, Roger Taylor wrote:
> >
> > >
> > > Btw, CoCoNet was just ROM'ed 5 minutes ago.  The CoCo powers up
> > > CoCoNet READY!  The ROM is in an EPROM Pak and no real floppy
> > > controller is connected.  Problem is, it's a 27128 16K EPROM, so I'm
> > > not sure if this would work in a CoCo 3.
> > >
> >
> >If you need to have Super Extended Basic available on the CoCo 3, you can use
> >the same approach I used for Extended ADOS-3, which resides in a 27128.  When
> >you need to call a ROM routine that is in the upper 8K of your 
> >EPROM, you switch
> >to ROM mode first, and switch back to ROM/RAM mode on the return from the
> >routine (to somewhere not in the upper 8K) to re-enable Super Ext. Basic.
> >(Have your ROM test whether it is running on a CoCo 3 during 
> >initialization, and
> >do this only if a CoCo 3 is being used.)
> >
> >Art
> 
> 
> It seems like this should work on any CoCo using the same code.  Is 
> there a reason why I should check whether it's a CoCo 3 or not?  I 
> can understand if I'm having to use the GIME to do internal/external 
> ROM switching and so forth to access the upper 16K of my ROM then 
> CoCo 1,2 <> 3 checking might be necessary.
> 
> -- 
> Roger Taylor
> 
> http://www.wordofthedayonline.com
> 
> 
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