Re: [stella] RAM optimization

Subject: Re: [stella] RAM optimization
From: Mark De Smet <de-smet@xxxxxxxxxxxxxxx>
Date: Tue, 20 Jun 2000 23:09:07 -0500 (CDT)
> > >Has anyone ever tried using some of the unused data bits in the TIA
> > >registers for general purpose RAM storage?
> >
> >Never tried, but it's most likely impossible, since all of the TIA
> >registers are write-only; the same addresses always access totally
> >different registers for reads and writes.

I am almost positive that it is impossible.  It takes a reasonable amout
of additional hardware to make those registers read/write.  

> What happens when you try to read values from $0E to $2C?  These are unused 
> in the Read table.

Unknown.  I'd give it a 50/50% chance that it either mirrors the other
read registers, or gives you 'nothing'(nothing is never nothing, and isn't
really 'random' either, but it is unknown.).  I don't know how we would
find this out besides trial and error.


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