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cc65/libsrc/c128/c128-stdjoy.s
cuz ee155a8553 Renamed the DEINSTALL vector to UNINSTALL.
Added a comment regarding usage of the driver when it is linked statically
to the application.


git-svn-id: svn://svn.cc65.org/cc65/trunk@1952 b7a2c559-68d2-44c3-8de9-860c34a00d81
2003-02-10 22:19:53 +00:00

122 lines
2.7 KiB
ArmAsm

;
; Standard joystick driver for the C128. May be used multiple times when linked
; to the statically application.
;
; Ullrich von Bassewitz, 2002-12-21
;
.include "zeropage.inc"
.include "joy-kernel.inc"
.include "joy-error.inc"
.include "c128.inc"
.macpack generic
; ------------------------------------------------------------------------
; Header. Includes jump table
.segment "JUMPTABLE"
; Driver signature
.byte $6A, $6F, $79 ; "joy"
.byte $00 ; 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 ; Future expansion
.byte $00 ; Future expansion
.byte $00 ; Future expansion
; Jump table.
.word INSTALL
.word UNINSTALL
.word COUNT
.word READ
; ------------------------------------------------------------------------
; Constants
JOY_COUNT = 2 ; Number of joysticks we support
; ------------------------------------------------------------------------
; Data.
.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 DEINSTALL 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
sei
sta CIA1_PRA
lda CIA1_PRB
cli
and #$1F
eor #$1F
rts
; Read joystick 2
joy2: ldx #0
lda #$E0
ldy #$FF
sei
sta CIA1_DDRA
lda CIA1_PRA
sty CIA1_DDRA
cli
and #$1F
eor #$1F
rts