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Re: Changing the ASCII character



Brian Hammack located an unguarded computer and managed to post ...
> 
>  Rubywand couldn't help but dribble back at Hector:
> 
> >  Somebody knows how to changing the ASCII characters in the APPLE IIe or in
> > a Multitech MPF-III, for example, I need to change the @ for a character
> 
>  R<|      As Nathan observes, what you want to do is swap in a custom
>    | character generator PROM for your Text display.
> 
> Hey, a thought:  During my Commodore programming days, all one had to
> do to make a custom character was to POKE values for each horizontal
> line of the character (8x8 grid).  I did whole character sets with
> FOR X=0 TO 7 : READ A : POKE xxxxx+X : NEXT : DATA xx,xx,xx,xx, (etc)
> -- so is there something similar available to the Apple?
>

     The C-64 is different from the Apple II.

     The Apple II's Text display characters are in ROM (or PROM or
somewhere else other than RAM).  When a Text screen is displayed the
ASCII values from RAM are translated on-the-fly to dot patterns via the
character generator ROM/PROM.

     If you want to change one or more Text display characters, you need
to swap in a custom PROM (or tack on a PROM and supply decoding, which
is more bother than just doing a new PROM).



Rubywand