;
; P.A.S.E. joystick driver for the Atmos
; May be used multiple times when linked to the statically application.
;
; Stefan Haubenthal, 2009-12-21
; Based on Ullrich von Bassewitz, 2002-12-20
;

	.include	"joy-kernel.inc"
	.include	"joy-error.inc"
;	.include	"atmos.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	$10			; JOY_UP
	.byte	$08			; JOY_DOWN
	.byte	$01			; JOY_LEFT
	.byte	$02			; JOY_RIGHT
	.byte	$20			; JOY_FIRE
	.byte	$00			; Future expansion
	.byte	$00			; Future expansion
	.byte	$00			; Future expansion

; Jump table.

	.addr	INSTALL
	.addr	UNINSTALL
	.addr	COUNT
	.addr	READ
	.addr	0			; IRQ entry unused

; ------------------------------------------------------------------------
; Constants

JOY_COUNT	= 2		; Number of joysticks we support

PRA		= $0301
DDRA		= $0303
PRA2		= $030F

; ------------------------------------------------------------------------
; Data.

.bss
temp1:	.byte	$00
temp2:	.byte	$00

.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	#0
;	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	#0
	rts

; ------------------------------------------------------------------------
; READ: Read a particular joystick passed in A.
;

READ:
	tay

	lda	PRA
	pha
	lda	DDRA
	pha
	lda	#%11000000
	sta	DDRA
	lda	#%10000000
	sta	PRA2
	lda	PRA2
	sta	temp1
	lda	#%01000000
	sta	PRA2
	lda	PRA
	sta	temp2
	pla
	sta	DDRA
	pla
	sta	PRA2

	ldx	#0
	tya
	bne	@L1
	lda	temp1
	eor	#$FF
	rts
@L1:	lda	temp2
	eor	#$FF
	rts