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Re: Newbie Assembly
Rubywand wrote:
>
> Simon Biber writes ...
> >
> > I'm just starting to learn Apple II assembly
> > using the mini-assembler on my
> > platinum //e. I'm using the instruction listing,
> > Appendix A of the "Apple II
> > Reference Manual".
> >
> > I've written this program which clears the
> > HGR screen to a colour (white by
> > default). It works! Can someone help me to
> > see if this is an optimal way of
> > doing this?
> >
> > 300: LDA #FF
> > 302: LDX #3F
> > 304: LDY #00
> > 306: STX $030E
> > 309: STY $030D
> > 30C: STA $0100
> > 30F: DEY
> > 310: BNE $0306
> > 312: DEX
> > 313: CPX #19
> > 315: BNE $0304
> >
....
Just noticed something else. The instruction at 313 should probably be
313: CPX #1F
You probably want to fill just the Hires-1 screen area-- i.e. $2000-$3FFF. (CPX
#19 would fill $1A00-$3FFF.)
Rubywand