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Re: Introducing Slammer!



On Jul 27, 4:43 am, Ivan Drucker <i...@ivanx.com> wrote:
>
> I wanted the Lam technique, but at machine language speed. So I tried to do
> something that I figured was probably impossible, and in any event crazy:
> write a routine consisting exclusively of bytes in the range $21-$5A, so
> that they could appear in REM lines that could be typed on every Apple II.
> This meant the only useful memory I could address was $0021-$005A, the only
> operands I could use were #$21-#$5A, and the only instructions I had
> available were AND BIT BMI BVC CLI EOR JMPa LSR PHA PLP ROL RTI.
> (I used all but one of them.) It took nearly a year to complete, and I gave up
> at least once along the way, but now you have it, and it works!

Genuine 6502 hacking at it's best. A truly great effort!

> (If anyone is curious, I can detail how I managed this on my web
> page or on c.s.a2.p.)

Please!

bye
Marcus