Cabal Neo Geo Port

[tcdev]

Here's iq_132's comment about the NeoSD:

_vblank_callback
    ori     #$2700, SR               ; first item in vblank
    clr.b   $300001                ; kick watchdog
    move.w  #$7, $3c000c.l                 ; ack irq
    cmpi.b  #$1, $10d2ff            ; have we gone through init process?
    bne.s     _dont_use_game_vblank        ; no, jump to $122
    ; do game vblank here

I've always hooked into the "demo game" routine to run my games. I'm not entirely surprised the vblank hack is causing issues.