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Re: IIGS tech questions...

David,

> I recall that $C029 (NEWVIDEO) has to be modified using
> read-modify-write, specifically so you don't change the state of bit 0
> (it is normally set). If you clear it, the system will usually crash.

    Do you have an explanation why read-modify-write is needed?  Without 
read-modify-write like LDA and STA will crash.  It requires AND or ORA to 
clear or set individual bit.  I would wish to reproduce crashes in Apple 
IIgs Emulator.

Bryan Parkoff