H-Int - Uploading scanlines to VScroll without registers

; ---------------------------------------------------------------------------
; Horizontal interrupt - Title Screen
; ---------------------------------------------------------------------------

; ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||


HBlank_Title:

@scanlines: =   $DF
@startaddr: =   $FFFF8000


        ; each entry is 1 word (2 bytes), with the position
        ; to copy to VScroll. Table must be generated in
        ; main loop, outside H-Int
n:      =   0
        rept    (@scanlines-1)
        move.l  #$40020010,$C00004      ; 10 bytes 28(5/2)
        move.w  (@startaddr+n).w,$C00000    ; 8 bytes 24(5/1)
        addi.l  #28,v_hblank+2          ; 8 bytes 28(5/1)
        rte                 ; 2 bytes 20(5/0)
                            ; Total: 28 bytes
n:      =   n+2
        endr

@Final:     ;move.l #$40020010,$C00004
        ;move.w (@startaddr+n).w,$C00000
        move.w  #$8ADF,$C00004
        move.l  #@Null,v_hblank+2
@Null:      rte