Defence Force Wiki

The Generic Joystick Drivers provide a set of routines for reading each type of joystick interface but outputting the sensed movement in a common format.

The common format comprises of two memory locations called joy_Left and joy_Right (Zero Page or main memory). Each bit of each byte indicates the joystick movement made.

The Code for the drivers also use common labels which should use the #DEFINE construct and be placed at the top of your source code. The labels are as follows. You may freely cut and paste the lines below.

     #define ayc_Register $FF
     #define ayc_Inactive $DD
     #define ayc_Write    $FD
     #define ayc_Read     $DF
     ;
     #define via_portb    $0300
     #define via_porta_hs $0301
     #define via_ddrb     $0302
     #define via_ddra     $0303
     #define via_t1cl     $0304
     #define via_t1ch     $0305
     #define via_t1ll     $0306
     #define via_t1lh     $0307
     #define via_t2cl     $0308
     #define via_t2ll     $0308
     #define via_t2ch     $0309
     #define via_sr       $030A
     #define via_acr      $030B
     #define via_pcr      $030C
     #define via_ifr      $030D
     #define via_ier      $030E
     #define via_porta    $030F
     ;
     #define dkt_LeftJoy  $0310
     #define dkt_RightJoy $0320
     ;
     #define via2_portb    $0320
     #define via2_porta_hs $0321
     #define via2_ddrb     $0322
     #define via2_ddra     $0323
     #define via2_t1cl     $0324
     #define via2_t1ch     $0325
     #define via2_t1ll     $0326
     #define via2_t1lh     $0327
     #define via2_t2cl     $0328
     #define via2_t2ll     $0328
     #define via2_t2ch     $0329
     #define via2_sr       $032A
     #define via2_acr      $032B
     #define via2_pcr      $032C
     #define via2_ifr      $032D
     #define via2_ier      $032E
     #define via2_porta    $032F