2 ; Standard joystick driver for the Plus/4. May be used multiple times when linked
3 ; to the statically application.
5 ; Ullrich von Bassewitz, 2002-12-21
8 .include "zeropage.inc"
10 .include "joy-kernel.inc"
11 .include "joy-error.inc"
12 .include "../plus4/plus4.inc"
17 ; ------------------------------------------------------------------------
18 ; Header. Includes jump table
24 .byte $6A, $6F, $79 ; "joy"
25 .byte JOY_API_VERSION ; Driver API version number
27 ; Button state masks (8 values)
34 .byte $00 ; Future expansion
35 .byte $00 ; Future expansion
36 .byte $00 ; Future expansion
45 ; ------------------------------------------------------------------------
48 JOY_COUNT = 2 ; Number of joysticks we support
51 ; ------------------------------------------------------------------------
57 ; ------------------------------------------------------------------------
58 ; INSTALL routine. Is called after the driver is loaded into memory. If
59 ; possible, check if the hardware is present and determine the amount of
61 ; Must return an JOY_ERR_xx code in a/x.
67 ; rts ; Run into UNINSTALL instead
69 ; ------------------------------------------------------------------------
70 ; UNINSTALL routine. Is called before the driver is removed from memory.
71 ; Can do cleanup or whatever. Must not return anything.
78 ; ------------------------------------------------------------------------
79 ; COUNT: Return the total number of available joysticks in a/x.
87 ; ------------------------------------------------------------------------
88 ; READ: Read a particular joystick passed in A.
91 READ: ldy #$FA ; Load index for joystick #1
92 tax ; Test joystick number
94 ldy #$FB ; Load index for joystick #2
99 ldx #$00 ; Clear high byte