mirror of https://github.com/cc65/cc65.git
837 lines
20 KiB
ArmAsm
837 lines
20 KiB
ArmAsm
;
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; Mouse driver for ST & Amiga mouses and Atari trakball.
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;
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; Original access routines: 05/07/2000 Freddy Offenga
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; Converted to driver: Christian Groessler, 2014-01-04
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;
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; Defines:
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; AMIGA_MOUSE - builds Amiga mouse version
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; TRAK_MOUSE - builds trakball version
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; If none of these defines are active, the ST mouse version
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; is being built.
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;
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;DEBUG = 1
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DISABLE_TIMEOUT = 30 ; # of vertical blank interrupts after which, if
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; no mouse motion occurred, the polling IRQ gets
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; disabled.
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; VBI frequency is 50Hz for PAL and 60Hz for NTSC
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.include "zeropage.inc"
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.include "mouse-kernel.inc"
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.include "atari.inc"
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.macpack generic
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.macpack module
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.if .not ( .defined (AMIGA_MOUSE) .or .defined (TRAK_MOUSE))
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ST_MOUSE = 1
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.endif
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; ------------------------------------------------------------------------
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; Header. Includes jump table
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.if .defined (ST_MOUSE)
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.ifdef __ATARIXL__
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module_header _atrxst_mou
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.else
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module_header _atrst_mou
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.endif
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.elseif .defined (AMIGA_MOUSE)
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.ifdef __ATARIXL__
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module_header _atrxami_mou
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.else
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module_header _atrami_mou
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.endif
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.elseif .defined (TRAK_MOUSE)
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.ifdef __ATARIXL__
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module_header _atrxtrk_mou
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.else
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module_header _atrtrk_mou
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.endif
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.endif
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HEADER:
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; Driver signature
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.byte $6d, $6f, $75 ; "mou"
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.byte MOUSE_API_VERSION ; Mouse driver API version number
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; Library reference
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libref: .addr $0000
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; Jump table
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.addr INSTALL
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.addr UNINSTALL
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.addr HIDE
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.addr SHOW
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.addr SETBOX
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.addr GETBOX
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.addr MOVE
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.addr BUTTONS
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.addr POS
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.addr INFO
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.addr IOCTL
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.addr IRQ
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; Mouse driver flags
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.byte MOUSE_FLAG_LATE_IRQ
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; Callback table, set by the kernel before INSTALL is called
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CHIDE: jmp $0000 ; Hide the cursor
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CSHOW: jmp $0000 ; Show the cursor
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CPREP: jmp $0000 ; Prepare to move the cursor
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CDRAW: jmp $0000 ; Draw the cursor
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CMOVEX: jmp $0000 ; Move the cursor to X coord
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CMOVEY: jmp $0000 ; Move the cursor to Y coord
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;----------------------------------------------------------------------------
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; Constants
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SCREEN_HEIGHT = 191
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SCREEN_WIDTH = 319
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.enum JOY
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UP = $01
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DOWN = $02
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LEFT = $04
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RIGHT = $08
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.endenum
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;----------------------------------------------------------------------------
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; Global variables. The bounding box values are sorted so that they can be
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; written with the least effort in the SETBOX and GETBOX routines, so don't
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; reorder them.
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.bss
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Vars:
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YPos: .res 2 ; Current mouse position, Y
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XPos: .res 2 ; Current mouse position, X
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XMin: .res 2 ; X1 value of bounding box
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YMin: .res 2 ; Y1 value of bounding box
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XMax: .res 2 ; X2 value of bounding box
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YMax: .res 2 ; Y2 value of bounding box
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Buttons: .res 1 ; Button mask
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OldButton: .res 1 ; previous buttons
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XPosWrk: .res 2
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YPosWrk: .res 2
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irq_enabled: .res 1 ; flag indicating that the high frequency polling interrupt is enabled
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old_porta_vbi: .res 1 ; previous PORTA value of the VBI interrupt (IRQ)
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how_long: .res 1 ; counter for how many VBI interrupts the mouse hasn't been moved
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in_irq: .res 1 ; flag indicating high-frequency polling interrupt is active
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.if .defined (AMIGA_MOUSE) .or .defined (ST_MOUSE)
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dumx: .res 1
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dumy: .res 1
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.endif
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.ifdef TRAK_MOUSE
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oldval: .res 1
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.endif
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.ifndef __ATARIXL__
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OldT2: .res 2
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.else
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.data
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set_VTIMR2_handler:
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.byte $4C, 0, 0
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.endif
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.rodata
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; Default values for some of the above variables
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; (We use ".proc" because we want to define both a label and a scope.)
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.proc DefVars
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.word (SCREEN_HEIGHT+1)/2 ; YPos
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.word (SCREEN_WIDTH+1)/2 ; XPos
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.word 0 ; XMin
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.word 0 ; YMin
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.word SCREEN_WIDTH ; XMax
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.word SCREEN_HEIGHT ; YMax
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.byte 0 ; Buttons
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.endproc
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.ifdef ST_MOUSE
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; ST mouse lookup table
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STTab: .byte $FF,$01,$00,$01
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.byte $00,$FF,$00,$01
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.byte $01,$00,$FF,$00
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.byte $01,$00,$01,$FF
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.endif
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.ifdef AMIGA_MOUSE
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; Amiga mouse lookup table
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AmiTab: .byte $FF,$01,$00,$FF
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.byte $00,$FF,$FF,$01
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.byte $01,$FF,$FF,$00
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.byte $FF,$00,$01,$FF
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.endif
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.code
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;----------------------------------------------------------------------------
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; INSTALL routine. Is called after the driver is loaded into memory. If
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; possible, check if the hardware is present.
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; Must return an MOUSE_ERR_xx code in a/x.
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INSTALL:
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; Initialize variables. Just copy the default stuff over
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ldx #.sizeof(DefVars)-1
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@L1: lda DefVars,x
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sta Vars,x
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dex
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bpl @L1
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; Make sure the mouse cursor is at the default location.
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lda XPos
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sta XPosWrk
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ldx XPos+1
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stx XPosWrk+1
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jsr CMOVEX
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lda YPos
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sta YPosWrk
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ldx YPos+1
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stx YPosWrk+1
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jsr CMOVEY
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; Install timer irq routine to poll mouse.
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.ifdef __ATARIXL__
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; Setup pointer to wrapper install/deinstall function.
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lda libref
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sta set_VTIMR2_handler+1
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lda libref+1
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sta set_VTIMR2_handler+2
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; Install my handler.
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sec
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lda #<T2Han
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ldx #>T2Han
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jsr set_VTIMR2_handler
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.else
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lda VTIMR2
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sta OldT2
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lda VTIMR2+1
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sta OldT2+1
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php
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sei
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lda #<T2Han
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sta VTIMR2
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lda #>T2Han
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sta VTIMR2+1
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plp
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.endif
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lda #%00000001
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sta AUDCTL
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lda #0
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sta AUDC2
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lda #15
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sta AUDF2
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sta STIMER
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lda PORTA
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and #$0f
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sta old_porta_vbi
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; Done
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ldx #MOUSE_ERR_OK
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.assert MOUSE_ERR_OK = 0, error
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txa
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rts
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;----------------------------------------------------------------------------
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; UNINSTALL routine. Is called before the driver is removed from memory.
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; No return code required (the driver is removed from memory on return).
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UNINSTALL:
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; uninstall timer irq routine
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lda POKMSK
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and #%11111101 ; timer 2 disable
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sta IRQEN
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sta POKMSK
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.ifdef __ATARIXL__
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clc
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jsr set_VTIMR2_handler
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.else
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php
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sei
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lda OldT2
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sta VTIMR2
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lda OldT2+1
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sta VTIMR2+1
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plp
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.endif
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; fall thru...
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;----------------------------------------------------------------------------
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; HIDE routine. Is called to hide the mouse pointer. The mouse kernel manages
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; a counter for calls to show/hide, and the driver entry point is only called
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; if the mouse is currently visible and should get hidden. For most drivers,
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; no special action is required besides hiding the mouse cursor.
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; No return code required.
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HIDE: php
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sei
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jsr CHIDE
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plp
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rts
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;----------------------------------------------------------------------------
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; SHOW routine. Is called to show the mouse pointer. The mouse kernel manages
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; a counter for calls to show/hide, and the driver entry point is only called
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; if the mouse is currently hidden and should become visible. For most drivers,
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; no special action is required besides enabling the mouse cursor.
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; No return code required.
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SHOW: php
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sei
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jsr CSHOW
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plp
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rts
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;----------------------------------------------------------------------------
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; SETBOX: Set the mouse bounding box. The parameters are passed as they come
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; from the C program, that is, a pointer to a mouse_box struct in a/x.
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; No checks are done if the mouse is currently inside the box, this is the job
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; of the caller. It is not necessary to validate the parameters, trust the
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; caller and save some code here. No return code required.
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SETBOX: sta ptr1
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stx ptr1+1 ; Save data pointer
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ldy #.sizeof (MOUSE_BOX)-1
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php
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sei
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@L1: lda (ptr1),y
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sta XMin,y
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dey
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bpl @L1
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plp
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rts
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;----------------------------------------------------------------------------
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; GETBOX: Return the mouse bounding box. The parameters are passed as they
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; come from the C program, that is, a pointer to a mouse_box struct in a/x.
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GETBOX: sta ptr1
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stx ptr1+1 ; Save data pointer
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ldy #.sizeof (MOUSE_BOX)-1
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php
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sei
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@L1: lda XMin,y
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sta (ptr1),y
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dey
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bpl @L1
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plp
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rts
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;----------------------------------------------------------------------------
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; MOVE: Move the mouse to a new position. The position is passed as it comes
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; from the C program, that is: X on the stack and Y in a/x. The C wrapper will
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; remove the parameter from the stack on return.
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; No checks are done if the new position is valid (within the bounding box or
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; the screen). No return code required.
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;
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MOVE: php
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sei ; No interrupts
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pha
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txa
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pha
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jsr CPREP
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pla
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tax
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pla
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sta YPos
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sta YPosWrk
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stx YPos+1 ; New Y position
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stx YPosWrk+1
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jsr CMOVEY ; Set it
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ldy #$01
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lda (sp),y
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sta XPos+1
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sta XPosWrk+1
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tax
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dey
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lda (sp),y
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sta XPos ; New X position
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sta XPosWrk
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jsr CMOVEX ; Move the cursor
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jsr CDRAW
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plp ; Restore interrupt flag
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rts
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;----------------------------------------------------------------------------
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; BUTTONS: Return the button mask in a/x.
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BUTTONS:
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lda Buttons
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ldx #$00
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rts
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;----------------------------------------------------------------------------
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; POS: Return the mouse position in the MOUSE_POS struct pointed to by ptr1.
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; No return code required.
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POS: ldy #MOUSE_POS::XCOORD ; Structure offset
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php
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sei ; Disable interrupts
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lda XPos ; Transfer the position
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sta (ptr1),y
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lda XPos+1
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iny
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sta (ptr1),y
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lda YPos
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iny
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sta (ptr1),y
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lda YPos+1
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plp ; Restore interrupt flag
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iny
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sta (ptr1),y ; Store last byte
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rts ; Done
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;----------------------------------------------------------------------------
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; INFO: Returns mouse position and current button mask in the MOUSE_INFO
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; struct pointed to by ptr1. No return code required.
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;
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; We're cheating here to keep the code smaller: The first fields of the
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; mouse_info struct are identical to the mouse_pos struct, so we will just
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; call _mouse_pos to initialize the struct pointer and fill the position
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; fields.
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INFO: jsr POS
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; Fill in the button state
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lda Buttons
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ldy #MOUSE_INFO::BUTTONS
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sta (ptr1),y
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rts
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;----------------------------------------------------------------------------
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; IOCTL: Driver defined entry point. The wrapper will pass a pointer to ioctl
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; specific data in ptr1, and the ioctl code in A.
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; Must return an error code in a/x.
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;
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IOCTL: lda #<MOUSE_ERR_INV_IOCTL ; We don't support ioclts for now
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ldx #>MOUSE_ERR_INV_IOCTL
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rts
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;----------------------------------------------------------------------------
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; IRQ: Irq handler entry point. Called as a subroutine but in IRQ context
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; (so be careful). The routine MUST return carry set if the interrupt has been
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; 'handled' - which means that the interrupt source is gone. Otherwise it
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; MUST return carry clear.
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;
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IRQ: lda PORTA ; mouse port contents
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and #$0f ; check port 1 only
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ldx irq_enabled
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bne @L1
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; IRQ is disabled, check for mouse motion and enable IRQ if mouse motion detected
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cmp old_porta_vbi
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beq @L3 ; no motion
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lda #0
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sta ATRACT ; disable "attract mode"
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; Turn mouse polling IRQ back on
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lda POKMSK
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ora #%00000010 ; timer 2 enable
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sta POKMSK
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sta IRQEN
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sta irq_enabled
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bne @L3
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; not reached
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; IRQ is enabled
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@L1: cmp old_porta_vbi ; mouse motion since last VBI?
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sta old_porta_vbi
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beq @L2 ; no, increment timeout to disable IRQ
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lda #0
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sta how_long ; yes, reinitialize wait counter
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beq @L3
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; not reached
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@L2: inc how_long ; no motion, increment wait counter
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lda how_long
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cmp #DISABLE_TIMEOUT ; timeout?
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bcc @L3 ; no
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lda #0 ; yes, turn off IRQ
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sta how_long
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; no mouse input -- turn IRQ off
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sta irq_enabled
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lda POKMSK
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and #%11111101 ; timer 2 disable
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sta IRQEN
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sta POKMSK
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; Check for a pressed button and place the result into Buttons
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@L3: ldx #0
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lda TRIG0 ; joystick #0 trigger
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bne @L4 ; not pressed
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ldx #MOUSE_BTN_LEFT
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@L4: stx Buttons
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jsr CPREP
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; Disable "attract mode" if button status has changed
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lda Buttons
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cmp OldButton
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beq @L5
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sta OldButton
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lda #0
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sta ATRACT
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; Limit the X coordinate to the bounding box
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@L5: lda XPosWrk+1
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ldy XPosWrk
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tax
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cpy XMin
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sbc XMin+1
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bpl @L6
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ldy XMin
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ldx XMin+1
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jmp @L7
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@L6: txa
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cpy XMax
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sbc XMax+1
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bmi @L7
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ldy XMax
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ldx XMax+1
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@L7: sty XPos
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stx XPos+1
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tya
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jsr CMOVEX
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; Limit the Y coordinate to the bounding box
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lda YPosWrk+1
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ldy YPosWrk
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tax
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cpy YMin
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sbc YMin+1
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bpl @L8
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ldy YMin
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ldx YMin+1
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jmp @L9
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@L8: txa
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cpy YMax
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sbc YMax+1
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bmi @L9
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ldy YMax
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ldx YMax+1
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@L9: sty YPos
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stx YPos+1
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tya
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jsr CMOVEY
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jsr CDRAW
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.ifdef DEBUG
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; print on upper right corner 'E' or 'D', indicating the IRQ is enabled or disabled
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ldy irq_enabled
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beq @L10
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lda #37 ; screen code for 'E'
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.byte $2c ; bit opcode, eats next 2 bytes
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@L10: lda #36 ; screen code for 'D'
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ldy #39
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sta (SAVMSC),y
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.endif
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clc
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rts
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;----------------------------------------------------------------------------
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; T2Han: Local IRQ routine to poll mouse
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;
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T2Han: lda CRITIC ; if CRITIC flag is set, disable the
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|
bne disable_me ; high frequency polling IRQ, in order
|
|
; not to interfere with SIO I/O (e.g.
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|
; floppy access or serial I/O)
|
|
|
|
lda in_irq ; handler entered again?
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|
bne skip ; yes, ignore this interrupt
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|
inc in_irq
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|
cli ; enable IRQs so that we don't block them for too long
|
|
|
|
tya
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|
pha
|
|
txa
|
|
pha
|
|
|
|
.ifdef DEBUG
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|
lda RANDOM
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|
sta COLBK
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|
.endif
|
|
|
|
lda PORTA
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|
tay
|
|
|
|
.ifdef ST_MOUSE
|
|
|
|
; ST mouse version
|
|
|
|
and #%00000011
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|
ora dumx
|
|
tax
|
|
lda STTab,x
|
|
bmi nxst
|
|
|
|
beq xist
|
|
|
|
dec XPosWrk
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|
lda XPosWrk
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|
cmp #255
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|
bne nxst
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|
dec XPosWrk+1
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|
jmp nxst
|
|
|
|
xist: inc XPosWrk
|
|
bne nxst
|
|
inc XPosWrk+1
|
|
|
|
nxst: tya
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|
and #%00001100
|
|
ora dumy
|
|
tax
|
|
lda STTab,x
|
|
bmi nyst
|
|
|
|
bne yst
|
|
|
|
dec YPosWrk
|
|
lda YPosWrk
|
|
cmp #255
|
|
bne nyst
|
|
dec YPosWrk+1
|
|
jmp nyst
|
|
|
|
yst: inc YPosWrk
|
|
bne nyst
|
|
inc YPosWrk+1
|
|
|
|
; store old readings
|
|
|
|
nyst: tya
|
|
and #%00000011
|
|
asl
|
|
asl
|
|
sta dumx
|
|
tya
|
|
and #%00001100
|
|
lsr
|
|
lsr
|
|
sta dumy
|
|
|
|
.elseif .defined (AMIGA_MOUSE)
|
|
|
|
; Amiga mouse version
|
|
|
|
lsr
|
|
and #%00000101
|
|
ora dumx
|
|
tax
|
|
lda AmiTab,x
|
|
bmi nxami
|
|
|
|
bne xiami
|
|
|
|
dec XPosWrk
|
|
lda XPosWrk
|
|
cmp #255
|
|
bne nxami
|
|
dec XPosWrk+1
|
|
jmp nxami
|
|
|
|
xiami: inc XPosWrk
|
|
bne nxami
|
|
inc XPosWrk+1
|
|
|
|
nxami: tya
|
|
|
|
and #%00000101
|
|
ora dumy
|
|
tax
|
|
lda AmiTab,x
|
|
bmi nyami
|
|
|
|
bne yiami
|
|
|
|
dec YPosWrk
|
|
lda YPosWrk
|
|
cmp #255
|
|
bne nyami
|
|
dec YPosWrk+1
|
|
jmp nyami
|
|
|
|
yiami: inc YPosWrk
|
|
bne nyami
|
|
inc YPosWrk+1
|
|
|
|
; store old readings
|
|
|
|
nyami: tya
|
|
and #%00001010
|
|
sta dumx
|
|
tya
|
|
and #%00000101
|
|
asl
|
|
sta dumy
|
|
|
|
.elseif .defined (TRAK_MOUSE)
|
|
|
|
; trakball version
|
|
|
|
eor oldval
|
|
and #%00001000
|
|
beq horiz
|
|
|
|
tya
|
|
and #%00000100
|
|
beq mmup
|
|
|
|
inc YPosWrk
|
|
bne horiz
|
|
inc YPosWrk+1
|
|
bne horiz
|
|
|
|
mmup: dec YPosWrk
|
|
lda YPosWrk
|
|
cmp #255
|
|
bne horiz
|
|
dec YPosWrk+1
|
|
|
|
horiz: tya
|
|
eor oldval
|
|
and #%00000010
|
|
beq mmexit
|
|
|
|
tya
|
|
and #%00000001
|
|
beq mmleft
|
|
|
|
inc XPosWrk
|
|
bne mmexit
|
|
inc XPosWrk+1
|
|
bne mmexit
|
|
|
|
mmleft: dec XPosWrk
|
|
lda XPosWrk
|
|
cmp #255
|
|
bne mmexit
|
|
dec XPosWrk+1
|
|
|
|
mmexit: sty oldval
|
|
|
|
.endif
|
|
|
|
pla
|
|
tax
|
|
pla
|
|
tay
|
|
dec in_irq
|
|
skip:
|
|
.ifdef __ATARIXL__
|
|
rts
|
|
.else
|
|
pla
|
|
rti
|
|
.endif
|
|
|
|
|
|
; Disable the interrupt source which caused us to be called.
|
|
; The interrupt will be enabled again by the "IRQ" routine.
|
|
; The "IRQ" routine, despite its name, is called from the
|
|
; vertical blank NMI interrupt *only* if the CRITIC flag has
|
|
; been cleared.
|
|
|
|
disable_me:
|
|
lda POKMSK
|
|
and #%11111101 ; timer 2 disable
|
|
sta IRQEN
|
|
sta POKMSK
|
|
lda #0
|
|
sta irq_enabled
|
|
lda PORTA
|
|
and #$0f
|
|
sta old_porta_vbi
|
|
.ifdef __ATARIXL__
|
|
rts
|
|
.else
|
|
pla
|
|
rti
|
|
.endif
|