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Re: ZipGS CDA bug

David Empson writes ...
> 
> Rubywand <rubywand@swbell.net> wrote:
> 
> >     As to why the original CDA might want to write to $00/C05D, I don't
> > know.
> 
> The Zip Chip (and Zip GS) use the annunciator locations ($C058 to $C05F)
> to access the on-chip registers.  There is a special sequence to enable
> and disable access to the Zip registers, so that normal use of the
> annunciators still works.
> 
> For the Zip GS, writing to $C05D sets the CPU speed (a 4 bit field, with
> sixteen settings ranging from 6.25% to 100%).
 ....

     So, I guess, since the speed setting works, the only down side of not
doing the final Store A Long to 00/C05D as intended is that Annunciator2 ends
up with its state changed?

     Thanks for the info! (Where did you find it?)



Rubywand