mirror of
https://github.com/cc65/cc65.git
synced 2024-12-23 19:29:37 +00:00
Workaround for "phantom" key presses in the C128 "joystick" mouse driver.
This commit is contained in:
Christian Groessler
parent
d4c9b25b2f
commit
608dbc2cec
@ -11,6 +11,8 @@
|
||||
|
||||
.macpack generic
|
||||
|
||||
IRQInd = $2FD
|
||||
|
||||
; ------------------------------------------------------------------------
|
||||
; Header. Includes jump table
|
||||
|
||||
@ -25,6 +27,7 @@ HEADER:
|
||||
|
||||
; Library reference
|
||||
|
||||
libref:
|
||||
.addr $0000
|
||||
|
||||
; Jump table
|
||||
@ -70,6 +73,15 @@ SCREEN_WIDTH = 320
|
||||
FIRE = $10
|
||||
.endenum
|
||||
|
||||
;----------------------------------------------------------------------------
|
||||
; data segment
|
||||
|
||||
.data
|
||||
|
||||
chainIRQ:
|
||||
.byte $4c ; JMP opcode
|
||||
.word 0 ; pointer to ROM IRQ handler (will be set at runtime)
|
||||
|
||||
;----------------------------------------------------------------------------
|
||||
; 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
|
||||
@ -92,6 +104,10 @@ INIT_save: .res 1
|
||||
|
||||
Temp: .res 1
|
||||
|
||||
; Keyboard buffer fill level at start of interrupt
|
||||
|
||||
old_key_count: .res 1
|
||||
|
||||
.rodata
|
||||
|
||||
; Default values for above variables
|
||||
@ -146,6 +162,35 @@ INSTALL:
|
||||
jsr CMOVEY
|
||||
cli
|
||||
|
||||
; Initialize our IRQ magic
|
||||
|
||||
lda IRQInd+1
|
||||
sta chainIRQ+1
|
||||
lda IRQInd+2
|
||||
sta chainIRQ+2
|
||||
lda libref
|
||||
sta ptr3
|
||||
lda libref+1
|
||||
sta ptr3+1
|
||||
ldy #2
|
||||
lda (ptr3),y
|
||||
sta IRQInd+1
|
||||
iny
|
||||
lda (ptr3),y
|
||||
sta IRQInd+2
|
||||
iny
|
||||
lda #<(callback-1)
|
||||
sta (ptr3),y
|
||||
iny
|
||||
lda #>(callback-1)
|
||||
sta (ptr3),y
|
||||
iny
|
||||
lda #<(chainIRQ-1)
|
||||
sta (ptr3),y
|
||||
iny
|
||||
lda #>(chainIRQ-1)
|
||||
sta (ptr3),y
|
||||
|
||||
; Done, return zero (= MOUSE_ERR_OK)
|
||||
|
||||
ldx #$00
|
||||
@ -157,6 +202,12 @@ INSTALL:
|
||||
; No return code required (the driver is removed from memory on return).
|
||||
|
||||
UNINSTALL:
|
||||
|
||||
lda chainIRQ+1
|
||||
sta IRQInd+1
|
||||
lda chainIRQ+2
|
||||
sta IRQInd+2
|
||||
|
||||
jsr HIDE ; Hide cursor on exit
|
||||
lda INIT_save
|
||||
sta INIT_STATUS
|
||||
@ -320,6 +371,8 @@ IOCTL: lda #<MOUSE_ERR_INV_IOCTL ; We don't support ioclts for now
|
||||
;
|
||||
|
||||
IRQ: jsr CPREP
|
||||
lda KEY_COUNT
|
||||
sta old_key_count
|
||||
lda #$7F
|
||||
sta CIA1_PRA
|
||||
lda CIA1_PRB ; Read joystick #0
|
||||
@ -436,3 +489,29 @@ IRQ: jsr CPREP
|
||||
@SkipY: jsr CDRAW
|
||||
clc ; Interrupt not "handled"
|
||||
rts
|
||||
|
||||
;----------------------------------------------------------------------------
|
||||
; Called after ROM IRQ handler has been run.
|
||||
; Check if there was joystick activity before and/or after the ROM handler.
|
||||
; If there was activity, discard the key presses since they are most
|
||||
; probably "phantom" key presses.
|
||||
|
||||
callback:
|
||||
ldx old_key_count
|
||||
cpx KEY_COUNT
|
||||
beq @nokey
|
||||
|
||||
lda Temp ; keypress before?
|
||||
bne @discard_key ; yes, discard key
|
||||
|
||||
lda #$7F
|
||||
sta CIA1_PRA
|
||||
lda CIA1_PRB ; Read joystick #0
|
||||
and #$1F
|
||||
eor #$1F ; keypress after
|
||||
beq @nokey ; no, probably a real key press
|
||||
|
||||
@discard_key:
|
||||
stx KEY_COUNT ; set old keyboard buffer fill level
|
||||
|
||||
@nokey: rts
|
||||
|
||||
@ -4,6 +4,8 @@
|
||||
; 2013-07-25, Greg King
|
||||
;
|
||||
|
||||
.include "c128.inc"
|
||||
|
||||
.export mouse_libref, _pen_adjuster
|
||||
|
||||
.data
|
||||
@ -21,3 +23,70 @@ mouse_libref: ; generic label for mouse-kernel
|
||||
;
|
||||
_pen_adjuster:
|
||||
.addr $0000
|
||||
.addr IRQStub2
|
||||
callback: ; callback into mouse driver after ROM IRQ handler has been run
|
||||
.addr $0000 ; (filled in by mouse driver)
|
||||
jmp_rom_hdlr: ; "trampoline" to jump to ROM IRQ handler
|
||||
.addr $0000 ; (filled in by mouse driver)
|
||||
|
||||
|
||||
.segment "LOWCODE"
|
||||
|
||||
; Called from irq.s when it thinks it chains to the original handler.
|
||||
; ROM is banked in again. In order to call the callback we have to
|
||||
; bank it out one more time.
|
||||
|
||||
IRQStub2:
|
||||
|
||||
; Call ROM handler and prepare stack so that it will return to us.
|
||||
|
||||
; setup fake IRQ stack frame which will return to "IRQCont"
|
||||
lda #>@IRQCont
|
||||
pha
|
||||
lda #<@IRQCont
|
||||
pha
|
||||
php
|
||||
|
||||
; mimic the contents saved on the stack by the ROM IRQ entry handler
|
||||
pha ; A
|
||||
pha ; X
|
||||
pha ; Y
|
||||
lda #MMU_CFG_CC65 ; MMU configuration which will be active after the ROM handler returns
|
||||
pha
|
||||
|
||||
; push address of ROM handler on stack and jump to it
|
||||
lda jmp_rom_hdlr+1
|
||||
pha
|
||||
lda jmp_rom_hdlr
|
||||
pha
|
||||
rts ; jump to ROM handler
|
||||
|
||||
; our MMU configuration byte we pushed on the stack before (MMU_CFG_CC65) is now active
|
||||
|
||||
@IRQCont:
|
||||
|
||||
; call mouse driver callback routine
|
||||
lda #>(@IRQCont2-1)
|
||||
pha
|
||||
lda #<(@IRQCont2-1)
|
||||
pha
|
||||
lda callback+1
|
||||
pha
|
||||
lda callback
|
||||
pha
|
||||
rts ; jump to callback routine
|
||||
|
||||
@IRQCont2:
|
||||
|
||||
; return from interrupt
|
||||
; We could just jump to $FF33, but since I don't know whether this address is valid in all
|
||||
; ROM versions, duplicate that code here.
|
||||
|
||||
pla
|
||||
sta MMU_CR ; MMU configuration register
|
||||
pla
|
||||
tay
|
||||
pla
|
||||
tax
|
||||
pla
|
||||
rti
|
||||
|
||||
Loading…
Reference in New Issue
Block a user