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cc65/libsrc/atari/mou/atrtt.s
2014-01-20 11:40:13 +01:00

478 lines
13 KiB
ArmAsm

;
; Mouse driver for Atari Touch Tablet
;
; Christian Groessler, 2014-01-05
;
.include "zeropage.inc"
.include "mouse-kernel.inc"
.include "atari.inc"
.macpack generic
; ------------------------------------------------------------------------
; Header. Includes jump table
.segment "JUMPTABLE"
HEADER:
; Driver signature
.byte $6d, $6f, $75 ; "mou"
.byte MOUSE_API_VERSION ; Mouse driver API version number
; Library reference
.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
; Default values for above variables
.rodata
; (We use ".proc" because we want to define both a label and a scope.)
.proc DefVars
.word SCREEN_HEIGHT/2 ; YPos
.word SCREEN_WIDTH/2 ; XPos
.word 0 ; XMin
.word 0 ; YMin
.word SCREEN_WIDTH ; XMax
.word SCREEN_HEIGHT ; YMax
.byte 0 ; Buttons
.endproc
.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
ldx XPos+1
jsr CMOVEX
lda YPos
ldx YPos+1
jsr CMOVEY
; 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 = HIDE ; Hide cursor on exit
;----------------------------------------------------------------------------
; 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
stx YPos+1 ; New Y position
jsr CMOVEY ; Set it
ldy #$01
lda (sp),y
sta XPos+1
tax
dey
lda (sp),y
sta XPos ; New X position
jsr CMOVEX ; Move the cursor
jsr CSHOW
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:
; Check for a pressed button and place the result into Buttons
ldx #0
stx Buttons
lda PORTA ; get other buttons
eor #255
tax
and #5 ; pen button and left button are mapped to left mouse button
beq @L01
lda #MOUSE_BTN_LEFT
ora Buttons
sta Buttons
@L01: txa
and #8
beq @L02
lda #MOUSE_BTN_RIGHT
ora Buttons
sta Buttons
; If we read 228 for X or Y positions, we assume the user has lifted the pen
; and don't change the cursor position.
@L02: lda PADDL0
cmp #228
beq @Cont ; CF set if equal
lda PADDL1
cmp #228 ; CF set if equal
@Cont: php ; remember CF
jsr CPREP
plp ; restore CF
bcc @L03
jmp @Show
@L03: ldx #0
stx XPos+1
stx YPos+1
; Get cursor position
; -------------------
; The touch pad is read thru the paddle potentiometers. The possible
; values are 1..228. Since the maximum value is less than the X
; dimension we have to "stretch" this value. In order to use only
; divisions by powers of two, we use the following appoximation:
; 320/227 = 1.4096
; 1+1/2-1/8+1/32 = 1.4062
; For Y we subtract 1/8 of it to get in the YMax ballpark.
; 228-228/8=199.5
; A small area in the Y dimension of the touchpad isn't used with
; this approximation. The Y value is inverted, (0,0) is the bottom
; left corner of the touchpad.
; X
ldx PADDL0 ; get X postion
dex ; decrement, since it's 1-based
stx XPos
txa
lsr a
tax
clc
adc XPos
sta XPos
bcc @L04
inc XPos+1
@L04: txa
lsr a ; port value / 4
lsr a ; port value / 8
tax
sec
lda XPos
stx XPos
sbc XPos
sta XPos
bcs @L05
dec XPos+1
@L05: txa
lsr a ; port value / 16
lsr a ; port value / 32
clc
adc XPos
sta XPos
bcc @L06
inc XPos+1
@L06: tay
lda XPos+1
tax
; Limit the X coordinate to the bounding box
cpy XMin
sbc XMin+1
bpl @L07
ldy XMin
ldx XMin+1
jmp @L08
@L07: txa
cpy XMax
sbc XMax+1
bmi @L08
ldy XMax
ldx XMax+1
@L08: sty XPos
stx XPos+1
; Move the mouse pointer to the new X pos
tya
jsr CMOVEX
; Y
ldx PADDL1 ; get Y postion
dex ; decrement, since it's 1-based
stx YPos
lda #228
sec
sbc YPos ; invert value
tax
lsr a
lsr a
lsr a
sta YPos
txa
sec
sbc YPos
sta YPos
tay
lda YPos+1
tax
; Limit the Y coordinate to the bounding box
cpy YMin
sbc YMin+1
bpl @L09
ldy YMin
ldx YMin+1
jmp @L10
@L09: txa
cpy YMax
sbc YMax+1
bmi @L10
ldy YMax
ldx YMax+1
@L10: sty YPos
stx YPos+1
; Move the mouse pointer to the new X pos
tya
jsr CMOVEY
@Show: jsr CDRAW
clc ; Interrupt not "handled"
rts