Arkanoid: The search for a RWTS

[Steve Nickolas <usotsuki@buric.co>]

Arkanoid doesn't seem to have a normal RWTS, though my understanding is it 
doesn't have any copy protection to begin with, or that's the impression I 
got from Hack-Zapple, so I'm just going to assume it has a way of reading 
sectors that resembles RWTS or at least Mini-RWTS...

In tracing, I found code at BB35, B810, B813, B895, B8AC, B8B5, B8CD and 
B8D5.  B895's access to the drive is a "stepper motor" hit, so I suppose 
this is where the track seek code is?

In my first analysis, here is BB00-BB7F.

          .org      $BB00

          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $40

LBB2A:    lda       $AD
          and       #$38
          cmp       $AC
          bne       LBB33
          rts

LBB33:    sta       $AC
          lda       $C0E9
          ldy       #$00
          ldx       #$00
LBB3C:    dey
          bne       LBB3C
          dex
          bne       LBB3C
          lda       $AC
          lsr
          lsr
          lsr
          tax
          ldy       LBB61, x
          ldx       #$0F
          lda       #$00
          sta       $80
          lda       #$FE
          sta       $81
LBB55:    jsr       $B806
          dec       $81
          dex
          bpl       LBB55
          lda       $C0E8
          rts

LBB61:    .byte          $16, $18, $1A, $1C, $1E, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00
          .byte     $00, $00, $00, $00, $00, $00, $00, $00

-uso.