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"
18 ; ------------------------------------------------------------------------
19 ; Header. Includes jump table
21 module_header _c64_hitjoy_joy
25 .byte $6A, $6F, $79 ; "joy"
26 .byte JOY_API_VERSION ; Driver API version number
39 ; ------------------------------------------------------------------------
42 JOY_COUNT = 4 ; Number of joysticks we support
44 ; ------------------------------------------------------------------------
45 ; Data. Written in the IRQ, read by the READ routine
54 ; ------------------------------------------------------------------------
55 ; INSTALL routine. Is called after the driver is loaded into memory. If
56 ; possible, check if the hardware is present and determine the amount of
58 ; Must return an JOY_ERR_xx code in a/x.
65 ; rts ; Run into UNINSTALL instead
67 ; ------------------------------------------------------------------------
68 ; UNINSTALL routine. Is called before the driver is removed from memory.
69 ; Can do cleanup or whatever. Must not return anything.
75 ; ------------------------------------------------------------------------
76 ; IRQ entry point. Is called from the C layer as a subroutine in the
77 ; interrupt. The routine MUST return carry set if the interrupt has been
78 ; 'handled' - which means that the interrupt source is gone. Otherwise it
79 ; MUST return carry clear.
83 ldy #$00 ; port b direction
86 sty $dd05 ; cia2 timer a highbyte
87 sty $dc05 ; cia1 timer a highbyte
89 sty $dd04 ; cia2 timer a lowbyte
90 sty $dc04 ; cia1 timer a lowbyte
93 sta $dd0e ; control register a
101 sta $dc0e ; control register a
105 ; serial port: output
108 lda $dd01 ;read cia 2 port b
113 lda $dd02 ;cia 2 port a
114 and #%11111011 ;data direction
115 sta $dd02 ;=> bit 2 input
117 lda $dd00 ;read cia 2 p.A
118 and #%00000100 ;check bit 2
125 lda $dd01 ;read cia 2 port b
133 ldx #$ff ;serial data register
134 stx $dc0c ;=> writing $ff causes
136 ;count signals at cnt1
138 ldx $dd0c ;read cia 2 serial in
139 beq fire ;button press if zero
146 ; Default Value: $40/64 on PAL
150 ; Default Value: $25/37 on PAL
155 ; We do never "handle" the interrupt, we use it just as a timer.
159 ; ------------------------------------------------------------------------
160 ; COUNT: Return the total number of available joysticks in a/x.
163 COUNT: lda #<JOY_COUNT
167 ; ------------------------------------------------------------------------
168 ; READ: Read a particular joystick passed in A.
171 READ: tax ; Joystick number into X