1
0
mirror of https://github.com/cc65/cc65.git synced 2024-12-27 15:29:46 +00:00
cc65/libsrc/c128/mcbdefault.s
cuz e4de88958e Loadable mouse driver for the C128
git-svn-id: svn://svn.cc65.org/cc65/trunk@2966 b7a2c559-68d2-44c3-8de9-860c34a00d81
2004-03-29 17:27:48 +00:00

110 lines
2.8 KiB
ArmAsm

;
; Default mouse callbacks for the C64
;
; Ullrich von Bassewitz, 2004-03-20
;
; All functions in this module should be interrupt safe, because they may
; be called from an interrupt handler
;
.export _mouse_def_callbacks
.include "mouse-kernel.inc"
.include "c128.inc"
.macpack generic
; Sprite definitions. The first value can be changed to adjust the number
; of the sprite used for the mouse.
MOUSE_SPR = 0 ; Sprite used for the mouse
MOUSE_SPR_MASK = $01 .shl MOUSE_SPR ; Positive mask
MOUSE_SPR_NMASK = .lobyte(.not MOUSE_SPR_MASK) ; Negative mask
VIC_SPR_X = (VIC_SPR0_X + 2*MOUSE_SPR) ; Sprite X register
VIC_SPR_Y = (VIC_SPR0_Y + 2*MOUSE_SPR) ; Sprite Y register
.code
; --------------------------------------------------------------------------
; Hide the mouse pointer. Always called with interrupts disabled.
.proc hide
lda #MOUSE_SPR_NMASK
and VIC_SPR_ENA
sta VIC_SPR_ENA
rts
.endproc
; --------------------------------------------------------------------------
; Show the mouse pointer. Always called with interrupts disabled.
.proc show
lda #MOUSE_SPR_MASK
ora VIC_SPR_ENA
sta VIC_SPR_ENA
rts
.endproc
; --------------------------------------------------------------------------
; Move the mouse pointer X position to the value in a/x. Always called with
; interrupts disabled.
.proc movex
; Add the X correction and set the low byte. This frees A.
add #24 ; X correction
sta VIC_SPR_X
; Set the high byte
txa
adc #0
bne @L1 ; Branch if high byte not zero
lda VIC_SPR_HI_X ; Get high X bits of all sprites
and #MOUSE_SPR_NMASK ; Clear high bit for sprite
sta VIC_SPR_HI_X
rts
@L1: lda VIC_SPR_HI_X ; Get high X bits of all sprites
ora #MOUSE_SPR_MASK ; Set high bit for sprite
sta VIC_SPR_HI_X
rts
.endproc
; --------------------------------------------------------------------------
; Move the mouse pointer Y position to the value in a/x. Always called with
; interrupts disabled.
.proc movey
clc
ldx PALFLAG
bne @L1
adc #50 ; FIXME: Should be NTSC, is PAL value
sta VIC_SPR_Y ; Set Y position
rts
@L1: adc #50 ; Add PAL correction
sta VIC_SPR_Y ; Set Y position
rts
.endproc
; --------------------------------------------------------------------------
; Callback structure
.rodata
_mouse_def_callbacks:
.addr hide
.addr show
.addr movex
.addr movey