VSYNC in 9 bytes

["Edwin Blink" <edwin.blink@xxxxxxx>]

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