mirror of
https://github.com/cc65/cc65.git
synced 2024-11-09 04:08:11 +00:00
147 lines
3.2 KiB
ArmAsm
147 lines
3.2 KiB
ArmAsm
|
;
|
||
|
; PTV-3 Player joystick driver for the VIC20
|
||
|
;
|
||
|
; Stefan Haubenthal, 2005-05-25
|
||
|
; Groepaz/Hitmen, 2002-12-23
|
||
|
; obviously based on Ullrichs driver :)
|
||
|
; Using code from Steve Schmidtke
|
||
|
;
|
||
|
|
||
|
.include "zeropage.inc"
|
||
|
|
||
|
.include "joy-kernel.inc"
|
||
|
.include "joy-error.inc"
|
||
|
.include "vic20.inc"
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; Header. Includes jump table
|
||
|
|
||
|
.segment "JUMPTABLE"
|
||
|
|
||
|
; Driver signature
|
||
|
|
||
|
.byte $6A, $6F, $79 ; "joy"
|
||
|
.byte JOY_API_VERSION ; Driver API version number
|
||
|
|
||
|
; Button state masks (8 values)
|
||
|
|
||
|
.byte $01 ; JOY_UP
|
||
|
.byte $02 ; JOY_DOWN
|
||
|
.byte $04 ; JOY_LEFT
|
||
|
.byte $08 ; JOY_RIGHT
|
||
|
.byte $10 ; JOY_FIRE
|
||
|
.byte $00 ; JOY_FIRE2 unavailable
|
||
|
.byte $00 ; Future expansion
|
||
|
.byte $00 ; Future expansion
|
||
|
|
||
|
; Jump table.
|
||
|
|
||
|
.addr INSTALL
|
||
|
.addr UNINSTALL
|
||
|
.addr COUNT
|
||
|
.addr READ
|
||
|
.addr 0 ; IRQ entry unused
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; Constants
|
||
|
|
||
|
VIA1_PRB := VIA1 ; User port register
|
||
|
JOY_COUNT = 3 ; Number of joysticks we support
|
||
|
|
||
|
|
||
|
.code
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; INSTALL routine. Is called after the driver is loaded into memory. If
|
||
|
; possible, check if the hardware is present and determine the amount of
|
||
|
; memory available.
|
||
|
; Must return an JOY_ERR_xx code in a/x.
|
||
|
;
|
||
|
|
||
|
INSTALL:
|
||
|
lda #<JOY_ERR_OK
|
||
|
ldx #>JOY_ERR_OK
|
||
|
; rts ; Run into UNINSTALL instead
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; UNINSTALL routine. Is called before the driver is removed from memory.
|
||
|
; Can do cleanup or whatever. Must not return anything.
|
||
|
;
|
||
|
|
||
|
UNINSTALL:
|
||
|
rts
|
||
|
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; COUNT: Return the total number of available joysticks in a/x.
|
||
|
;
|
||
|
|
||
|
COUNT:
|
||
|
lda #<JOY_COUNT
|
||
|
ldx #>JOY_COUNT
|
||
|
rts
|
||
|
|
||
|
; ------------------------------------------------------------------------
|
||
|
; READ: Read a particular joystick passed in A.
|
||
|
;
|
||
|
|
||
|
READ: tax ; Joystick number into X
|
||
|
bne joy2
|
||
|
|
||
|
; Read joystick 1
|
||
|
|
||
|
joy1: lda #$7F ; mask for VIA2 JOYBIT: sw3
|
||
|
ldx #$C3 ; mask for VIA1 JOYBITS: sw0,sw1,sw2,sw4
|
||
|
sei ; necessary?
|
||
|
|
||
|
ldy VIA2_DDRB ; remember the date of DDRB
|
||
|
sta VIA2_DDRB ; set JOYBITS on this VIA for input
|
||
|
lda VIA2_JOY ; read JOYBIT: sw3
|
||
|
sty VIA2_DDRB ; restore the state of DDRB
|
||
|
asl ; Shift sw3 into carry
|
||
|
|
||
|
ldy VIA1_DDRA ; remember the state of DDRA
|
||
|
stx VIA1_DDRA ; set JOYBITS on this VIA for input
|
||
|
lda VIA1_JOY ; read JOYBITS: sw0,sw1,sw2,sw4
|
||
|
sty VIA1_DDRA ; restore the state of DDRA
|
||
|
|
||
|
cli ; necessary?
|
||
|
ror ; Shift sw3 into bit 7
|
||
|
and #$9E ; Mask relevant bits
|
||
|
eor #$9E ; Active states are inverted
|
||
|
|
||
|
rts
|
||
|
|
||
|
; Read joystick 2
|
||
|
|
||
|
joy2: lda #%10000000 ; via port B Data-Direction
|
||
|
sta VIA1_DDRB ; bit 7: out bit 6-0: in
|
||
|
|
||
|
dex
|
||
|
bne joy3
|
||
|
|
||
|
lda #$80 ; via port B read/write
|
||
|
sta VIA1_PRB ; (output one at PB7)
|
||
|
|
||
|
lda VIA1_PRB ; via port B read/write
|
||
|
and #$1f ; get bit 4-0 (PB4-PB0)
|
||
|
rts
|
||
|
|
||
|
; Read joystick 3
|
||
|
|
||
|
joy3: lda #$00 ; via port B read/write
|
||
|
sta VIA1_PRB ; (output zero at PB7)
|
||
|
|
||
|
lda VIA1_PRB ; via port B read/write
|
||
|
and #$0f ; get bit 3-0 (PB3-PB0)
|
||
|
sta tmp1 ; joy 4 directions
|
||
|
|
||
|
lda VIA1_PRB ; via port B read/write
|
||
|
and #%00100000 ; get bit 5 (PB5)
|
||
|
lsr
|
||
|
ora tmp1
|
||
|
|
||
|
ldx #0
|
||
|
rts
|
||
|
|