6529 db1f      in      a,($1f)          ; read kempston joystick
652b 5f        ld      e,a
652c 010000    ld      bc,$0000         ; reset resulting direction
652f cb43      bit     0,e              ; if pressed right
6531 c4f265    call    nz,$65f2         ; then update C to indicate moving right
6534 cb4b      bit     1,e              ; if pressed left
6536 c4ef65    call    nz,$65ef         ; then update C to indicate moving left
6539 cb53      bit     2,e              ; if pressed down
653b c4f565    call    nz,$65f5         ; then update B to indicate moving up -> SHOULD BE DOWN
653e cb5b      bit     3,e              ; if pressed up
6540 c4f865    call    nz,$65f8         ; then update B to indicate moving down -> SHOULD BE UP
6543 cb63      bit     4,e              ; if pressed fire
6545 c4e965    call    nz,$65e9         ; then update $5b03 directly to indicate fire
6548 ed433f68  ld      ($683f),bc       ; store resulting direction in $683f
654c c9        ret