From 608dbc2cec5e9cc7e9e9b96c139d838837c7df3b Mon Sep 17 00:00:00 2001
From: Christian Groessler <chris@groessler.org>
Date: Tue, 22 Apr 2014 15:48:49 +0200
Subject: [PATCH 1/4] Workaround for "phantom" key presses in the C128
"joystick" mouse driver.
---
libsrc/c128/mou/c128-joy.s | 79 ++++++++++++++++++++++++++++++++++++++
libsrc/c128/mouseref.s | 69 +++++++++++++++++++++++++++++++++
2 files changed, 148 insertions(+)
diff --git a/libsrc/c128/mou/c128-joy.s b/libsrc/c128/mou/c128-joy.s
index be0cf227b..fb087c8fc 100644
--- a/libsrc/c128/mou/c128-joy.s
+++ b/libsrc/c128/mou/c128-joy.s
@@ -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
diff --git a/libsrc/c128/mouseref.s b/libsrc/c128/mouseref.s
index 90aeedf3a..290303075 100644
--- a/libsrc/c128/mouseref.s
+++ b/libsrc/c128/mouseref.s
@@ -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
From 4406307c2fee0e3e2369d03e38bf8c118c2393ac Mon Sep 17 00:00:00 2001
From: Christian Groessler <chris@groessler.org>
Date: Thu, 24 Apr 2014 00:27:06 +0200
Subject: [PATCH 2/4] Make the hooking and unhooking of the interrupt interrupt
safe.
---
libsrc/c128/mou/c128-joy.s | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/libsrc/c128/mou/c128-joy.s b/libsrc/c128/mou/c128-joy.s
index fb087c8fc..339fdc836 100644
--- a/libsrc/c128/mou/c128-joy.s
+++ b/libsrc/c128/mou/c128-joy.s
@@ -160,7 +160,6 @@ INSTALL:
lda YPos
ldx YPos+1
jsr CMOVEY
- cli
; Initialize our IRQ magic
@@ -190,6 +189,7 @@ INSTALL:
iny
lda #>(chainIRQ-1)
sta (ptr3),y
+ cli
; Done, return zero (= MOUSE_ERR_OK)
@@ -202,11 +202,12 @@ INSTALL:
; No return code required (the driver is removed from memory on return).
UNINSTALL:
-
lda chainIRQ+1
+ sei
sta IRQInd+1
lda chainIRQ+2
sta IRQInd+2
+ cli
jsr HIDE ; Hide cursor on exit
lda INIT_save
From 54be6de9bc0afa61b4f15e1f651832a614176852 Mon Sep 17 00:00:00 2001
From: Christian Groessler <chris@groessler.org>
Date: Fri, 25 Apr 2014 00:21:41 +0200
Subject: [PATCH 3/4] Workaround for "phantom" key presses in the C128 "1351"
mouse driver.
---
libsrc/c128/mou/c128-1351.s | 74 ++++++++++++++++++++++++++++++++----
libsrc/c128/mou/c128-joy.s | 27 +------------
libsrc/c128/mou/callback.inc | 29 ++++++++++++++
3 files changed, 97 insertions(+), 33 deletions(-)
create mode 100644 libsrc/c128/mou/callback.inc
diff --git a/libsrc/c128/mou/c128-1351.s b/libsrc/c128/mou/c128-1351.s
index 8aec3b7b7..c81ad04d0 100644
--- a/libsrc/c128/mou/c128-1351.s
+++ b/libsrc/c128/mou/c128-1351.s
@@ -12,6 +12,8 @@
.macpack generic
+IRQInd = $2FD
+
; ------------------------------------------------------------------------
; Header. Includes jump table
@@ -26,6 +28,7 @@ HEADER:
; Library reference
+libref:
.addr $0000
; Jump table
@@ -63,6 +66,15 @@ CMOVEY: jmp $0000 ; Move the cursor to Y coord
SCREEN_HEIGHT = 200
SCREEN_WIDTH = 320
+;----------------------------------------------------------------------------
+; 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
@@ -85,6 +97,11 @@ OldValue: .res 1 ; Temp for MoveCheck routine
NewValue: .res 1 ; Temp for MoveCheck routine
INIT_save: .res 1
+Buttons: .res 1 ; Button mask
+
+; Keyboard buffer fill level at start of interrupt
+
+old_key_count: .res 1
.rodata
@@ -138,6 +155,35 @@ INSTALL:
lda YPos
ldx YPos+1
jsr CMOVEY
+
+; 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
cli
; Done, return zero (= MOUSE_ERR_OK)
@@ -151,6 +197,13 @@ INSTALL:
; No return code required (the driver is removed from memory on return).
UNINSTALL:
+ lda chainIRQ+1
+ sei
+ sta IRQInd+1
+ lda chainIRQ+2
+ sta IRQInd+2
+ cli
+
jsr HIDE ; Hide cursor on exit
lda INIT_save
sta INIT_STATUS
@@ -250,14 +303,8 @@ MOVE: sei ; No interrupts
; BUTTONS: Return the button mask in a/x.
BUTTONS:
- lda #$7F
- sei
- sta CIA1_PRA
- lda CIA1_PRB ; Read joystick #0
- cli
- ldx #0
- and #$1F
- eor #$1F
+ lda Buttons
+ ldx #$00
rts
;----------------------------------------------------------------------------
@@ -320,6 +367,15 @@ 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
+ and #$1F
+ eor #$1F ; Make all bits active high
+ sta Buttons
+
lda SID_ADConv1 ; Get mouse X movement
ldy OldPotX
jsr MoveCheck ; Calculate movement vector
@@ -450,3 +506,5 @@ MoveCheck:
clc
rts
+.define OLD_BUTTONS Buttons ; tells callback.inc where the old port status is stored
+.include "callback.inc"
diff --git a/libsrc/c128/mou/c128-joy.s b/libsrc/c128/mou/c128-joy.s
index 339fdc836..83255b64e 100644
--- a/libsrc/c128/mou/c128-joy.s
+++ b/libsrc/c128/mou/c128-joy.s
@@ -491,28 +491,5 @@ IRQ: jsr CPREP
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
+.define OLD_BUTTONS Temp ; tells callback.inc where the old port status is stored
+.include "callback.inc"
diff --git a/libsrc/c128/mou/callback.inc b/libsrc/c128/mou/callback.inc
new file mode 100644
index 000000000..ea64b8913
--- /dev/null
+++ b/libsrc/c128/mou/callback.inc
@@ -0,0 +1,29 @@
+;
+; Callback routine called from the IRQ handler after the ROM IRQ handler
+; had been run.
+;
+; Christian Groessler, 24.04.2014
+;
+; 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 OLD_BUTTONS ; 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
From 6307815ada83e09589864fe218baab2c907e1641 Mon Sep 17 00:00:00 2001
From: Christian Groessler <chris@groessler.org>
Date: Sat, 26 Apr 2014 11:55:24 +0200
Subject: [PATCH 4/4] Correctly map out ROM when needed in the "phantom keys"
workaround.
---
libsrc/c128/mou/c128-1351.s | 40 ++++++++++++++++++++++---------------
libsrc/c128/mou/c128-joy.s | 40 ++++++++++++++++++++++---------------
libsrc/c128/mouseref.s | 8 +++++++-
3 files changed, 55 insertions(+), 33 deletions(-)
diff --git a/libsrc/c128/mou/c128-1351.s b/libsrc/c128/mou/c128-1351.s
index c81ad04d0..e55c1d01b 100644
--- a/libsrc/c128/mou/c128-1351.s
+++ b/libsrc/c128/mou/c128-1351.s
@@ -66,15 +66,6 @@ CMOVEY: jmp $0000 ; Move the cursor to Y coord
SCREEN_HEIGHT = 200
SCREEN_WIDTH = 320
-;----------------------------------------------------------------------------
-; 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
@@ -103,6 +94,10 @@ Buttons: .res 1 ; Button mask
old_key_count: .res 1
+; original IRQ vector
+
+old_irq: .res 2
+
.rodata
; Default values for above variables
@@ -158,20 +153,27 @@ INSTALL:
; Initialize our IRQ magic
- lda IRQInd+1
- sta chainIRQ+1
+ ; remember ROM IRQ continuation address
lda IRQInd+2
- sta chainIRQ+2
+ sta old_irq+1
+ lda IRQInd+1
+ sta old_irq
+
lda libref
sta ptr3
lda libref+1
sta ptr3+1
+
+ ; set ROM IRQ continuation address to point to the provided routine
ldy #2
lda (ptr3),y
sta IRQInd+1
iny
lda (ptr3),y
sta IRQInd+2
+
+ ; set address of our IRQ callback routine
+ ; since it's called via "rts" we have to use "address-1"
iny
lda #<(callback-1)
sta (ptr3),y
@@ -179,10 +181,16 @@ INSTALL:
lda #>(callback-1)
sta (ptr3),y
iny
- lda #<(chainIRQ-1)
+
+ ; set ROM entry point vector
+ ; since it's called via "rts" we have to decrement it by one
+ lda old_irq
+ sec
+ sbc #1
sta (ptr3),y
iny
- lda #>(chainIRQ-1)
+ lda old_irq+1
+ sbc #0
sta (ptr3),y
cli
@@ -197,10 +205,10 @@ INSTALL:
; No return code required (the driver is removed from memory on return).
UNINSTALL:
- lda chainIRQ+1
+ lda old_irq
sei
sta IRQInd+1
- lda chainIRQ+2
+ lda old_irq+1
sta IRQInd+2
cli
diff --git a/libsrc/c128/mou/c128-joy.s b/libsrc/c128/mou/c128-joy.s
index 83255b64e..c1dc2e019 100644
--- a/libsrc/c128/mou/c128-joy.s
+++ b/libsrc/c128/mou/c128-joy.s
@@ -73,15 +73,6 @@ 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
@@ -108,6 +99,10 @@ Temp: .res 1
old_key_count: .res 1
+; original IRQ vector
+
+old_irq: .res 2
+
.rodata
; Default values for above variables
@@ -163,20 +158,27 @@ INSTALL:
; Initialize our IRQ magic
- lda IRQInd+1
- sta chainIRQ+1
+ ; remember ROM IRQ continuation address
lda IRQInd+2
- sta chainIRQ+2
+ sta old_irq+1
+ lda IRQInd+1
+ sta old_irq
+
lda libref
sta ptr3
lda libref+1
sta ptr3+1
+
+ ; set ROM IRQ continuation address to point to the provided routine
ldy #2
lda (ptr3),y
sta IRQInd+1
iny
lda (ptr3),y
sta IRQInd+2
+
+ ; set address of our IRQ callback routine
+ ; since it's called via "rts" we have to use "address-1"
iny
lda #<(callback-1)
sta (ptr3),y
@@ -184,10 +186,16 @@ INSTALL:
lda #>(callback-1)
sta (ptr3),y
iny
- lda #<(chainIRQ-1)
+
+ ; set ROM entry point vector
+ ; since it's called via "rts" we have to decrement it by one
+ lda old_irq
+ sec
+ sbc #1
sta (ptr3),y
iny
- lda #>(chainIRQ-1)
+ lda old_irq+1
+ sbc #0
sta (ptr3),y
cli
@@ -202,10 +210,10 @@ INSTALL:
; No return code required (the driver is removed from memory on return).
UNINSTALL:
- lda chainIRQ+1
+ lda old_irq
sei
sta IRQInd+1
- lda chainIRQ+2
+ lda old_irq+1
sta IRQInd+2
cli
diff --git a/libsrc/c128/mouseref.s b/libsrc/c128/mouseref.s
index 290303075..630ff573f 100644
--- a/libsrc/c128/mouseref.s
+++ b/libsrc/c128/mouseref.s
@@ -26,7 +26,7 @@ _pen_adjuster:
.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
+jmp_rom_hdlr: ; original ROM indirect IRQ handler address
.addr $0000 ; (filled in by mouse driver)
@@ -54,11 +54,17 @@ IRQStub2:
lda #MMU_CFG_CC65 ; MMU configuration which will be active after the ROM handler returns
pha
+ ; map out ROM
+ ldy MMU_CR
+ sta MMU_CR
+
; push address of ROM handler on stack and jump to it
lda jmp_rom_hdlr+1
pha
lda jmp_rom_hdlr
pha
+
+ sty MMU_CR ; map in ROM
rts ; jump to ROM handler
; our MMU configuration byte we pushed on the stack before (MMU_CFG_CC65) is now active