Re: [stella] Re: Help with efficient code

Subject: Re: [stella] Re: Help with efficient code
From: Greg Miller <gmiller@xxxxxxxx>
Date: Tue, 30 Sep 1997 05:49:51 -0500
Jim Nitchals wrote:
> jump_table:
>         dc.w framistat    ; your assembler may prefer .word
>         dc.w dohickey
>         dc.w whachamacallit
>         dc.w thingy
>         dc.w dodad
> num_entries equ (*-jump_table)/2    ; some assemblers use $, not *
>                                     ; to refer to current address
> (or if all else fails:)
> num_entries equ 5         ; but it isn't as nice

Small note: I'm not sure about the 6507, but the 6502 and many of its variants
won't work properly, if a pointer in the table crosses a 256-byte page
boundary. Make sure your tables are either word-aligned or don't cross pages,
unless someone (Jim?) knows for sure whether the 6507 has this bug.
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