2 ; DXS/HIT-4 Player joystick driver for the C64
4 ; Groepaz/Hitmen, 2002-12-23
5 ; obviously based on Ullrichs driver :)
8 .include "zeropage.inc"
10 .include "joy-kernel.inc"
11 .include "joy-error.inc"
16 ; ------------------------------------------------------------------------
17 ; Header. Includes jump table
23 .byte $6A, $6F, $79 ; "joy"
24 .byte JOY_API_VERSION ; Driver API version number
26 ; Button state masks (8 values)
33 .byte $00 ; JOY_FIRE2 unavailable
34 .byte $00 ; Future expansion
35 .byte $00 ; Future expansion
45 ; ------------------------------------------------------------------------
48 JOY_COUNT = 4 ; Number of joysticks we support
50 ; ------------------------------------------------------------------------
51 ; Data. Written in the IRQ, read by the READ routine
60 ; ------------------------------------------------------------------------
61 ; INSTALL routine. Is called after the driver is loaded into memory. If
62 ; possible, check if the hardware is present and determine the amount of
64 ; Must return an JOY_ERR_xx code in a/x.
71 ; rts ; Run into UNINSTALL instead
73 ; ------------------------------------------------------------------------
74 ; UNINSTALL routine. Is called before the driver is removed from memory.
75 ; Can do cleanup or whatever. Must not return anything.
81 ; ------------------------------------------------------------------------
82 ; IRQ entry point. Is called from the C layer as a subroutine in the
87 ldy #$00 ; port b direction
90 sty $dd05 ; cia2 timer a highbyte
91 sty $dc05 ; cia1 timer a highbyte
93 sty $dd04 ; cia2 timer a lowbyte
94 sty $dc04 ; cia1 timer a lowbyte
97 sta $dd0e ; control register a
105 sta $dc0e ; control register a
109 ; serial port: output
112 lda $dd01 ;read cia 2 port b
117 lda $dd02 ;cia 2 port a
118 and #%11111011 ;data direction
119 sta $dd02 ;=> bit 2 input
121 lda $dd00 ;read cia 2 p.A
122 and #%00000100 ;check bit 2
129 lda $dd01 ;read cia 2 port b
137 ldx #$ff ;serial data register
138 stx $dc0c ;=> writing $ff causes
140 ;count signals at cnt1
142 ldx $dd0c ;read cia 2 serial in
143 beq fire ;button press if zero
150 ; Default Value: $40/64 on PAL
154 ; Default Value: $25/37 on PAL
161 ; ------------------------------------------------------------------------
162 ; COUNT: Return the total number of available joysticks in a/x.
165 COUNT: lda #<JOY_COUNT
169 ; ------------------------------------------------------------------------
170 ; READ: Read a particular joystick passed in A.
173 READ: tax ; Joystick number into X