Re: [stella] VSYNC in 9 bytes

Subject: Re: [stella] VSYNC in 9 bytes
From: "Aaron" <stella-receiver@xxxxxxxxxxxxxxxxx>
Date: Fri, 3 Sep 2004 07:10:36 +0100 (BST)
Edwin Blink said:
> I've been bytebusting a lot in keeping my menu I'm doing as(mall)ap and
> just had one of those bright moments. Just needed to share this with you
> guys:
>
> ;generates vertical sync pulse for 3 full scanlines.
> ;VBLANK should be set by the overscan code and is not set here
>
>     LDA    #$0E    ;each '1' bits generate a VSYNC ON line (bits 1..3)
> VSLP1    STA    WSYNC    ;1st '0' bit resets Vsync, 2nd '0' bit exit loop
>     STA VSYNC
>     LSR
>     BNE    VSLP1    ;branch until VYSNC has been reset

Well that's really great :)
Actually, using this code, Fall Down now fits into exactly 4k.  Thanks!

Aaron

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