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
30 ; Button state masks (8 values)
37 .byte $00 ; JOY_FIRE2 unavailable
38 .byte $00 ; Future expansion
39 .byte $00 ; Future expansion
49 ; ------------------------------------------------------------------------
52 JOY_COUNT = 4 ; Number of joysticks we support
54 ; ------------------------------------------------------------------------
55 ; Data. Written in the IRQ, read by the READ routine
64 ; ------------------------------------------------------------------------
65 ; INSTALL routine. Is called after the driver is loaded into memory. If
66 ; possible, check if the hardware is present and determine the amount of
68 ; Must return an JOY_ERR_xx code in a/x.
75 ; rts ; Run into UNINSTALL instead
77 ; ------------------------------------------------------------------------
78 ; UNINSTALL routine. Is called before the driver is removed from memory.
79 ; Can do cleanup or whatever. Must not return anything.
85 ; ------------------------------------------------------------------------
86 ; IRQ entry point. Is called from the C layer as a subroutine in the
87 ; interrupt. The routine MUST return carry set if the interrupt has been
88 ; 'handled' - which means that the interrupt source is gone. Otherwise it
89 ; MUST return carry clear.
93 ldy #$00 ; port b direction
96 sty $dd05 ; cia2 timer a highbyte
97 sty $dc05 ; cia1 timer a highbyte
99 sty $dd04 ; cia2 timer a lowbyte
100 sty $dc04 ; cia1 timer a lowbyte
103 sta $dd0e ; control register a
111 sta $dc0e ; control register a
115 ; serial port: output
118 lda $dd01 ;read cia 2 port b
123 lda $dd02 ;cia 2 port a
124 and #%11111011 ;data direction
125 sta $dd02 ;=> bit 2 input
127 lda $dd00 ;read cia 2 p.A
128 and #%00000100 ;check bit 2
135 lda $dd01 ;read cia 2 port b
143 ldx #$ff ;serial data register
144 stx $dc0c ;=> writing $ff causes
146 ;count signals at cnt1
148 ldx $dd0c ;read cia 2 serial in
149 beq fire ;button press if zero
156 ; Default Value: $40/64 on PAL
160 ; Default Value: $25/37 on PAL
165 ; We do never "handle" the interrupt, we use it just as a timer.
169 ; ------------------------------------------------------------------------
170 ; COUNT: Return the total number of available joysticks in a/x.
173 COUNT: lda #<JOY_COUNT
177 ; ------------------------------------------------------------------------
178 ; READ: Read a particular joystick passed in A.
181 READ: tax ; Joystick number into X