mirror of
https://github.com/cc65/cc65.git
synced 2024-06-15 17:30:06 +00:00
2c975d3642
Up to now static drivers were created via co65 from dynamic drivers. However there was an issue with that approach: The dynamic drivers are "o65 simple files" which obligates that they start with the 'code' segment. However dynamic drivers need to start with the module header - which is written to. For dynamic drivers this isn't more than a conceptual issue because they are always contain a 'data' segment and may therefore only be loaded into writable memory. However when dynamic drivers are converted to static drivers using co65 then that issue becomes a real problem as then the 'code' segment may end up in non-writable memory - and thus writing to the module header fails. Instead of changing the way dynamic drivers work I opted to rather make static driver creation totally independent from dynamic drivers. This allows to place the module header in the 'data' segment (see 'module.mac').
824 lines
19 KiB
ArmAsm
824 lines
19 KiB
ArmAsm
;
|
|
; Mouse driver for ST & Amiga mouses and Atari trakball.
|
|
;
|
|
; Original access routines: 05/07/2000 Freddy Offenga
|
|
; Converted to driver: Christian Groessler, 2014-01-04
|
|
;
|
|
; Defines:
|
|
; AMIGA_MOUSE - builds Amiga mouse version
|
|
; TRAK_MOUSE - builds trakball version
|
|
; If none of these defines are active, the ST mouse version
|
|
; is being built.
|
|
;
|
|
|
|
;DEBUG = 1
|
|
|
|
DISABLE_TIMEOUT = 30 ; # of vertical blank interrupts after which, if
|
|
; no mouse motion occurred, the polling IRQ gets
|
|
; disabled.
|
|
; VBI frequency is 50Hz for PAL and 60Hz for NTSC
|
|
|
|
.include "zeropage.inc"
|
|
.include "mouse-kernel.inc"
|
|
.include "atari.inc"
|
|
|
|
.macpack generic
|
|
.macpack module
|
|
|
|
.if .not ( .defined (AMIGA_MOUSE) .or .defined (TRAK_MOUSE))
|
|
ST_MOUSE = 1
|
|
.endif
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Header. Includes jump table
|
|
|
|
.if .defined (ST_MOUSE)
|
|
|
|
.ifdef __ATARIXL__
|
|
module_header _atrxst_mou
|
|
.else
|
|
module_header _atrst_mou
|
|
.endif
|
|
|
|
.elseif .defined (AMIGA_MOUSE)
|
|
|
|
.ifdef __ATARIXL__
|
|
module_header _atrxami_mou
|
|
.else
|
|
module_header _atrami_mou
|
|
.endif
|
|
|
|
.elseif .defined (TRAK_MOUSE)
|
|
|
|
.ifdef __ATARIXL__
|
|
module_header _atrxtrk_mou
|
|
.else
|
|
module_header _atrtrk_mou
|
|
.endif
|
|
|
|
.endif
|
|
|
|
HEADER:
|
|
|
|
; Driver signature
|
|
|
|
.byte $6d, $6f, $75 ; "mou"
|
|
.byte MOUSE_API_VERSION ; Mouse driver API version number
|
|
|
|
; Library reference
|
|
|
|
libref: .addr $0000
|
|
|
|
; Jump table
|
|
|
|
.addr INSTALL
|
|
.addr UNINSTALL
|
|
.addr HIDE
|
|
.addr SHOW
|
|
.addr SETBOX
|
|
.addr GETBOX
|
|
.addr MOVE
|
|
.addr BUTTONS
|
|
.addr POS
|
|
.addr INFO
|
|
.addr IOCTL
|
|
.addr IRQ
|
|
|
|
; Mouse driver flags
|
|
|
|
.byte MOUSE_FLAG_LATE_IRQ
|
|
|
|
; Callback table, set by the kernel before INSTALL is called
|
|
|
|
CHIDE: jmp $0000 ; Hide the cursor
|
|
CSHOW: jmp $0000 ; Show the cursor
|
|
CPREP: jmp $0000 ; Prepare to move the cursor
|
|
CDRAW: jmp $0000 ; Draw the cursor
|
|
CMOVEX: jmp $0000 ; Move the cursor to X coord
|
|
CMOVEY: jmp $0000 ; Move the cursor to Y coord
|
|
|
|
|
|
;----------------------------------------------------------------------------
|
|
; Constants
|
|
|
|
SCREEN_HEIGHT = 191
|
|
SCREEN_WIDTH = 319
|
|
|
|
.enum JOY
|
|
UP = $01
|
|
DOWN = $02
|
|
LEFT = $04
|
|
RIGHT = $08
|
|
.endenum
|
|
|
|
;----------------------------------------------------------------------------
|
|
; Global variables. The bounding box values are sorted so that they can be
|
|
; written with the least effort in the SETBOX and GETBOX routines, so don't
|
|
; reorder them.
|
|
|
|
.bss
|
|
|
|
Vars:
|
|
YPos: .res 2 ; Current mouse position, Y
|
|
XPos: .res 2 ; Current mouse position, X
|
|
XMin: .res 2 ; X1 value of bounding box
|
|
YMin: .res 2 ; Y1 value of bounding box
|
|
XMax: .res 2 ; X2 value of bounding box
|
|
YMax: .res 2 ; Y2 value of bounding box
|
|
Buttons: .res 1 ; Button mask
|
|
|
|
XPosWrk: .res 2
|
|
YPosWrk: .res 2
|
|
|
|
irq_enabled: .res 1 ; flag indicating that the high frequency polling interrupt is enabled
|
|
old_porta_vbi: .res 1 ; previous PORTA value of the VBI interrupt (IRQ)
|
|
how_long: .res 1 ; counter for how many VBI interrupts the mouse hasn't been moved
|
|
|
|
.if .defined (AMIGA_MOUSE) .or .defined (ST_MOUSE)
|
|
dumx: .res 1
|
|
dumy: .res 1
|
|
.endif
|
|
|
|
.ifdef TRAK_MOUSE
|
|
oldval: .res 1
|
|
.endif
|
|
|
|
.ifndef __ATARIXL__
|
|
OldT1: .res 2
|
|
.else
|
|
|
|
.data
|
|
set_VTIMR1_handler:
|
|
.byte $4C, 0, 0
|
|
.endif
|
|
|
|
.rodata
|
|
|
|
; Default values for some of the above variables
|
|
; (We use ".proc" because we want to define both a label and a scope.)
|
|
|
|
.proc DefVars
|
|
.word (SCREEN_HEIGHT+1)/2 ; YPos
|
|
.word (SCREEN_WIDTH+1)/2 ; XPos
|
|
.word 0 ; XMin
|
|
.word 0 ; YMin
|
|
.word SCREEN_WIDTH ; XMax
|
|
.word SCREEN_HEIGHT ; YMax
|
|
.byte 0 ; Buttons
|
|
.endproc
|
|
|
|
.ifdef ST_MOUSE
|
|
|
|
; ST mouse lookup table
|
|
|
|
STTab: .byte $FF,$01,$00,$01
|
|
.byte $00,$FF,$00,$01
|
|
.byte $01,$00,$FF,$00
|
|
.byte $01,$00,$01,$FF
|
|
|
|
.endif
|
|
|
|
.ifdef AMIGA_MOUSE
|
|
|
|
; Amiga mouse lookup table
|
|
|
|
AmiTab: .byte $FF,$01,$00,$FF
|
|
.byte $00,$FF,$FF,$01
|
|
.byte $01,$FF,$FF,$00
|
|
.byte $FF,$00,$01,$FF
|
|
|
|
.endif
|
|
|
|
.code
|
|
|
|
;----------------------------------------------------------------------------
|
|
; INSTALL routine. Is called after the driver is loaded into memory. If
|
|
; possible, check if the hardware is present.
|
|
; Must return an MOUSE_ERR_xx code in a/x.
|
|
|
|
INSTALL:
|
|
|
|
; Initialize variables. Just copy the default stuff over
|
|
|
|
ldx #.sizeof(DefVars)-1
|
|
@L1: lda DefVars,x
|
|
sta Vars,x
|
|
dex
|
|
bpl @L1
|
|
|
|
; Make sure the mouse cursor is at the default location.
|
|
|
|
lda XPos
|
|
sta XPosWrk
|
|
ldx XPos+1
|
|
stx XPosWrk+1
|
|
jsr CMOVEX
|
|
lda YPos
|
|
sta YPosWrk
|
|
ldx YPos+1
|
|
stx YPosWrk+1
|
|
jsr CMOVEY
|
|
|
|
; Install timer irq routine to poll mouse.
|
|
|
|
.ifdef __ATARIXL__
|
|
|
|
; Setup pointer to wrapper install/deinstall function.
|
|
lda libref
|
|
sta set_VTIMR1_handler+1
|
|
lda libref+1
|
|
sta set_VTIMR1_handler+2
|
|
|
|
; Install my handler.
|
|
sec
|
|
lda #<T1Han
|
|
ldx #>T1Han
|
|
jsr set_VTIMR1_handler
|
|
|
|
.else
|
|
|
|
lda VTIMR1
|
|
sta OldT1
|
|
lda VTIMR1+1
|
|
sta OldT1+1
|
|
|
|
php
|
|
sei
|
|
lda #<T1Han
|
|
sta VTIMR1
|
|
lda #>T1Han
|
|
sta VTIMR1+1
|
|
plp
|
|
|
|
.endif
|
|
|
|
lda #%00000001
|
|
sta AUDCTL
|
|
|
|
lda #0
|
|
sta AUDC1
|
|
|
|
lda #15
|
|
sta AUDF1
|
|
sta STIMER
|
|
|
|
.if 0 ; the IRQ will now be dynamically enabled when the mouse is moved
|
|
lda POKMSK
|
|
ora #%00000001 ; timer 1 enable
|
|
sta POKMSK
|
|
sta IRQEN
|
|
sta irq_enabled
|
|
.endif
|
|
|
|
lda PORTA
|
|
and #$0f
|
|
sta old_porta_vbi
|
|
|
|
; Done, return zero (= MOUSE_ERR_OK)
|
|
|
|
ldx #$00
|
|
txa
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; UNINSTALL routine. Is called before the driver is removed from memory.
|
|
; No return code required (the driver is removed from memory on return).
|
|
|
|
UNINSTALL:
|
|
|
|
; uninstall timer irq routine
|
|
|
|
lda POKMSK
|
|
and #%11111110 ; timer 1 disable
|
|
sta IRQEN
|
|
sta POKMSK
|
|
|
|
.ifdef __ATARIXL__
|
|
|
|
clc
|
|
jsr set_VTIMR1_handler
|
|
|
|
.else
|
|
|
|
php
|
|
sei
|
|
lda OldT1
|
|
sta VTIMR1
|
|
lda OldT1+1
|
|
sta VTIMR1+1
|
|
plp
|
|
|
|
.endif
|
|
; fall thru...
|
|
|
|
;----------------------------------------------------------------------------
|
|
; HIDE routine. Is called to hide the mouse pointer. The mouse kernel manages
|
|
; a counter for calls to show/hide, and the driver entry point is only called
|
|
; if the mouse is currently visible and should get hidden. For most drivers,
|
|
; no special action is required besides hiding the mouse cursor.
|
|
; No return code required.
|
|
|
|
HIDE: php
|
|
sei
|
|
jsr CHIDE
|
|
plp
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SHOW routine. Is called to show the mouse pointer. The mouse kernel manages
|
|
; a counter for calls to show/hide, and the driver entry point is only called
|
|
; if the mouse is currently hidden and should become visible. For most drivers,
|
|
; no special action is required besides enabling the mouse cursor.
|
|
; No return code required.
|
|
|
|
SHOW: php
|
|
sei
|
|
jsr CSHOW
|
|
plp
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SETBOX: Set the mouse bounding box. The parameters are passed as they come
|
|
; from the C program, that is, a pointer to a mouse_box struct in a/x.
|
|
; No checks are done if the mouse is currently inside the box, this is the job
|
|
; of the caller. It is not necessary to validate the parameters, trust the
|
|
; caller and save some code here. No return code required.
|
|
|
|
SETBOX: sta ptr1
|
|
stx ptr1+1 ; Save data pointer
|
|
|
|
ldy #.sizeof (MOUSE_BOX)-1
|
|
php
|
|
sei
|
|
|
|
@L1: lda (ptr1),y
|
|
sta XMin,y
|
|
dey
|
|
bpl @L1
|
|
|
|
plp
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; GETBOX: Return the mouse bounding box. The parameters are passed as they
|
|
; come from the C program, that is, a pointer to a mouse_box struct in a/x.
|
|
|
|
GETBOX: sta ptr1
|
|
stx ptr1+1 ; Save data pointer
|
|
|
|
ldy #.sizeof (MOUSE_BOX)-1
|
|
php
|
|
sei
|
|
|
|
@L1: lda XMin,y
|
|
sta (ptr1),y
|
|
dey
|
|
bpl @L1
|
|
|
|
plp
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; MOVE: Move the mouse to a new position. The position is passed as it comes
|
|
; from the C program, that is: X on the stack and Y in a/x. The C wrapper will
|
|
; remove the parameter from the stack on return.
|
|
; No checks are done if the new position is valid (within the bounding box or
|
|
; the screen). No return code required.
|
|
;
|
|
|
|
MOVE: php
|
|
sei ; No interrupts
|
|
|
|
pha
|
|
txa
|
|
pha
|
|
jsr CPREP
|
|
pla
|
|
tax
|
|
pla
|
|
|
|
sta YPos
|
|
sta YPosWrk
|
|
stx YPos+1 ; New Y position
|
|
stx YPosWrk+1
|
|
jsr CMOVEY ; Set it
|
|
|
|
ldy #$01
|
|
lda (sp),y
|
|
sta XPos+1
|
|
sta XPosWrk+1
|
|
tax
|
|
dey
|
|
lda (sp),y
|
|
sta XPos ; New X position
|
|
sta XPosWrk
|
|
jsr CMOVEX ; Move the cursor
|
|
|
|
jsr CDRAW
|
|
|
|
plp ; Restore interrupt flag
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; BUTTONS: Return the button mask in a/x.
|
|
|
|
BUTTONS:
|
|
lda Buttons
|
|
ldx #$00
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; POS: Return the mouse position in the MOUSE_POS struct pointed to by ptr1.
|
|
; No return code required.
|
|
|
|
POS: ldy #MOUSE_POS::XCOORD ; Structure offset
|
|
|
|
php
|
|
sei ; Disable interrupts
|
|
lda XPos ; Transfer the position
|
|
sta (ptr1),y
|
|
lda XPos+1
|
|
iny
|
|
sta (ptr1),y
|
|
lda YPos
|
|
iny
|
|
sta (ptr1),y
|
|
lda YPos+1
|
|
plp ; Restore interrupt flag
|
|
|
|
iny
|
|
sta (ptr1),y ; Store last byte
|
|
|
|
rts ; Done
|
|
|
|
;----------------------------------------------------------------------------
|
|
; INFO: Returns mouse position and current button mask in the MOUSE_INFO
|
|
; struct pointed to by ptr1. No return code required.
|
|
;
|
|
; We're cheating here to keep the code smaller: The first fields of the
|
|
; mouse_info struct are identical to the mouse_pos struct, so we will just
|
|
; call _mouse_pos to initialize the struct pointer and fill the position
|
|
; fields.
|
|
|
|
INFO: jsr POS
|
|
|
|
; Fill in the button state
|
|
|
|
lda Buttons
|
|
ldy #MOUSE_INFO::BUTTONS
|
|
sta (ptr1),y
|
|
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; IOCTL: Driver defined entry point. The wrapper will pass a pointer to ioctl
|
|
; specific data in ptr1, and the ioctl code in A.
|
|
; Must return an error code in a/x.
|
|
;
|
|
|
|
IOCTL: lda #<MOUSE_ERR_INV_IOCTL ; We don't support ioclts for now
|
|
ldx #>MOUSE_ERR_INV_IOCTL
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; IRQ: Irq handler entry point. Called as a subroutine but in IRQ context
|
|
; (so be careful). The routine MUST return carry set if the interrupt has been
|
|
; 'handled' - which means that the interrupt source is gone. Otherwise it
|
|
; MUST return carry clear.
|
|
;
|
|
|
|
IRQ: lda PORTA ; mouse port contents
|
|
and #$0f ; check port 1 only
|
|
ldx irq_enabled
|
|
bne @L1
|
|
|
|
; IRQ is disabled, check for mouse motion and enable IRQ if mouse motion detected
|
|
|
|
cmp old_porta_vbi
|
|
beq @L3 ; no motion
|
|
|
|
; Turn mouse polling IRQ back on
|
|
|
|
lda POKMSK
|
|
ora #%00000001 ; timer 1 enable
|
|
sta POKMSK
|
|
sta IRQEN
|
|
sta irq_enabled
|
|
bne @L3
|
|
; not reached
|
|
|
|
; IRQ is enabled
|
|
|
|
@L1: cmp old_porta_vbi ; mouse motion since last VBI?
|
|
sta old_porta_vbi
|
|
beq @L2 ; no, increment timeout to disable IRQ
|
|
|
|
lda #0
|
|
sta how_long ; yes, reinitialize wait counter
|
|
beq @L3
|
|
; not reached
|
|
|
|
@L2: inc how_long ; no motion, increment wait counter
|
|
lda how_long
|
|
cmp #DISABLE_TIMEOUT ; timeout?
|
|
bcc @L3 ; no
|
|
|
|
lda #0 ; yes, turn off IRQ
|
|
sta how_long
|
|
|
|
; no mouse input -- turn IRQ off
|
|
|
|
sta irq_enabled
|
|
lda POKMSK
|
|
and #%11111110 ; timer 1 disable
|
|
sta IRQEN
|
|
sta POKMSK
|
|
|
|
; Check for a pressed button and place the result into Buttons
|
|
|
|
@L3: ldx #0
|
|
lda TRIG0 ; joystick #0 trigger
|
|
bne @L4 ; not pressed
|
|
ldx #MOUSE_BTN_LEFT
|
|
@L4: stx Buttons
|
|
|
|
jsr CPREP
|
|
|
|
; Limit the X coordinate to the bounding box
|
|
|
|
lda XPosWrk+1
|
|
ldy XPosWrk
|
|
tax
|
|
cpy XMin
|
|
sbc XMin+1
|
|
bpl @L5
|
|
ldy XMin
|
|
ldx XMin+1
|
|
jmp @L6
|
|
|
|
@L5: txa
|
|
cpy XMax
|
|
sbc XMax+1
|
|
bmi @L6
|
|
ldy XMax
|
|
ldx XMax+1
|
|
@L6: sty XPos
|
|
stx XPos+1
|
|
tya
|
|
jsr CMOVEX
|
|
|
|
; Limit the Y coordinate to the bounding box
|
|
|
|
lda YPosWrk+1
|
|
ldy YPosWrk
|
|
tax
|
|
cpy YMin
|
|
sbc YMin+1
|
|
bpl @L7
|
|
ldy YMin
|
|
ldx YMin+1
|
|
jmp @L8
|
|
|
|
@L7: txa
|
|
cpy YMax
|
|
sbc YMax+1
|
|
bmi @L8
|
|
ldy YMax
|
|
ldx YMax+1
|
|
@L8: sty YPos
|
|
stx YPos+1
|
|
tya
|
|
jsr CMOVEY
|
|
|
|
jsr CDRAW
|
|
|
|
.ifdef DEBUG
|
|
; print on upper right corner 'E' or 'D', indicating the IRQ is enabled or disabled
|
|
ldy irq_enabled
|
|
beq @L9
|
|
lda #37 ; screen code for 'E'
|
|
.byte $2c ; bit opcode, eats next 2 bytes
|
|
@L9: lda #36 ; screen code for 'D'
|
|
ldy #39
|
|
sta (SAVMSC),y
|
|
.endif
|
|
|
|
clc
|
|
rts
|
|
|
|
|
|
;----------------------------------------------------------------------------
|
|
; T1Han: Local IRQ routine to poll mouse
|
|
;
|
|
|
|
T1Han: lda CRITIC ; if CRITIC flag is set, disable the
|
|
bne disable_me ; high frequency polling IRQ, in order
|
|
; not to interfere with SIO I/O (e.g.
|
|
; floppy access)
|
|
|
|
tya
|
|
pha
|
|
txa
|
|
pha
|
|
|
|
.ifdef DEBUG
|
|
lda RANDOM
|
|
sta COLBK
|
|
.endif
|
|
|
|
lda PORTA
|
|
tay
|
|
|
|
.ifdef ST_MOUSE
|
|
|
|
; ST mouse version
|
|
|
|
and #%00000011
|
|
ora dumx
|
|
tax
|
|
lda STTab,x
|
|
bmi nxst
|
|
|
|
beq xist
|
|
|
|
dec XPosWrk
|
|
lda XPosWrk
|
|
cmp #255
|
|
bne nxst
|
|
dec XPosWrk+1
|
|
jmp nxst
|
|
|
|
xist: inc XPosWrk
|
|
bne nxst
|
|
inc XPosWrk+1
|
|
|
|
nxst: tya
|
|
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
|
|
.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 #%11111110 ; timer 1 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
|