Working on loadable mouse drivers

git-svn-id: svn://svn.cc65.org/cc65/trunk@2953 b7a2c559-68d2-44c3-8de9-860c34a00d81

asminc/mouse-kernel.inc

@@ -6,7 +6,7 @@
 ;/*                                                                           */
 ;/*                                                                           */
 ;/*                                                                           */
-;/* (C) 2003      Ullrich von Bassewitz                                       */
+;/* (C) 2003-2004 Ullrich von Bassewitz                                       */
 ;/*               R<>merstra<72>e 52                                              */
 ;/*               D-70794 Filderstadt                                         */
 ;/* EMail:        uz@cc65.org                                                 */
@@ -75,10 +75,22 @@
                         .byte
             CSHOW       .addr
                         .byte
-            CMOVE       .addr
+            CMOVEX      .addr
+                        .byte
+            CMOVEY      .addr
         .endstruct
 .endstruct
 
+;------------------------------------------------------------------------------
+; The mouse callback structure
+
+.struct	MOUSE_CALLBACKS
+	HIDE	.addr			; Hide the mouse cursor
+	SHOW	.addr			; Show the mouse cursor
+       	MOVEX	.addr			; Move the mouse cursor
+        MOVEY   .addr                   ; Dito for Y
+.endstruct
+
 ;------------------------------------------------------------------------------
 ; The mouse API version, stored in MOUSE_HDR::VERSION
 
@@ -113,7 +125,6 @@ MOUSE_BTN_RIGHT         = $01
 ;------------------------------------------------------------------------------
 ; C callable functions
 
-        .global _mouse_set_callbacks
         .global _mouse_load_driver
         .global _mouse_unload
         .global _mouse_install

include/mouse.h

@@ -6,7 +6,7 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 2003      Ullrich von Bassewitz                                       */
+/* (C) 2003-2004 Ullrich von Bassewitz                                       */
 /*               R<>merstra<72>e 52                                              */
 /*               D-70794 Filderstadt                                         */
 /* EMail:        uz@cc65.org                                                 */
@@ -82,12 +82,20 @@ struct mouse_callbacks {
     void (*show) (void);
     /* Show the mouse cursor */
 
-    void (*move) (void);
+    void (*movex) (void);
-    /* Move the mouse cursor. This function is called, even when the cursor
+    /* Move the mouse cursor to the new X coordinate. This function is called,
-     * is currently invisible.
+     * even when the cursor is currently invisible.
+     */
+
+    void (*movey) (void);
+    /* Move the mouse cursor to the new Y coordinate. This function is called,
+     * even when the cursor is currently invisible.
      */
 };
 
+/* The default mouse callbacks */
+extern const struct mouse_callbacks mouse_def_callbacks;
+
 
 
 /*****************************************************************************/
@@ -96,20 +104,15 @@ struct mouse_callbacks {
 
 
 
-void __fastcall__ mouse_set_callbacks (const struct mouse_callbacks* c);
+unsigned char __fastcall__ mouse_load_driver (const struct mouse_callbacks* c,
-/* Sets the callbacks to be used by the driver. NOTE: The function will just
+                                              const char* driver);
- * remember the pointer, it will not copy the contents of the passed struct.
- * The latter is done in mouse_install. This means that the struct must be
- * valid at least until mouse_install is called. Do not use a local variable!
- */
-
-unsigned char __fastcall__ mouse_load_driver (const char* driver);
 /* Load and install a mouse driver, return an error code. */
 
 unsigned char __fastcall__ mouse_unload (void);
 /* Uninstall, then unload the currently loaded driver. */
 
-unsigned char __fastcall__ mouse_install (void* driver);
+unsigned char __fastcall__ mouse_install (const struct mouse_callbacks* c,
+                                          void* driver);
 /* Install an already loaded driver. Returns an error code. */
 
 unsigned char __fastcall__ mouse_uninstall (void);

libsrc/c64/.cvsignore

@@ -1,4 +1,5 @@
 *.emd
 *.joy
+*.mou
 *.ser
 *.tgi

libsrc/c64/Makefile

@@ -21,6 +21,9 @@
 %.joy:	%.o ../runtime/zeropage.o
 	@$(LD) -t module -o $@ $^
 
+%.mou:	%.o ../runtime/zeropage.o
+	@$(LD) -t module -o $@ $^
+
 %.ser:	%.o ../runtime/zeropage.o
 	@$(LD) -t module -o $@ $^
 
@@ -44,7 +47,7 @@ OBJS = 	_scrsize.o     	 	\
        	kbhit.o	       	 	\
         kernal.o                \
         mainargs.o              \
-       	mouse.o	       	 	\
+        mcbdefault.o            \
         randomize.o             \
         revers.o                \
         sysuname.o              \
@@ -57,6 +60,8 @@ EMDS = c64-georam.emd c64-ram.emd c64-ramcart.emd c64-reu.emd c64-vdc.emd
 
 JOYS = c64-hitjoy.joy c64-numpad.joy c64-ptvjoy.joy c64-stdjoy.joy
 
+MOUS = c64-1351.mou
+
 SERS = c64-swlink.ser
 
 TGIS = c64-320-200-2.tgi
@@ -66,14 +71,14 @@ TGIS = c64-320-200-2.tgi
 
 .PHONY:	all clean zap
 
-all: 	$(OBJS) $(EMDS) $(JOYS) $(SERS) $(TGIS)
+all: 	$(OBJS) $(EMDS) $(JOYS) $(MOUS) $(SERS) $(TGIS)
 
 ../runtime/zeropage.o:
 	$(MAKE) -C $(dir $@) $(notdir $@)
 
 clean:
-	@$(RM) $(OBJS) $(EMDS:.emd=.o) $(JOYS:.joy=.o) $(SERS:.ser=.o) $(TGIS:.tgi=.o)
+	@$(RM) $(OBJS) $(EMDS:.emd=.o) $(JOYS:.joy=.o) $(MOUS:.mou=.o) $(SERS:.ser=.o) $(TGIS:.tgi=.o)
 
 zap:	clean
-	@$(RM) $(EMDS) $(JOYS) $(SERS) $(TGIS)
+	@$(RM) $(EMDS) $(JOYS) $(MOUS) $(SERS) $(TGIS)
 

libsrc/c64/c64-1351.s

@@ -0,0 +1,365 @@
+;
+; Driver for the 1351 proportional mouse. Parts of the code are from
+; the Commodore 1351 mouse users guide.
+;
+; Ullrich von Bassewitz, 2003-12-29
+;
+
+        .include        "zeropage.inc"
+        .include        "mouse-kernel.inc"
+	.include	"c64.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
+
+; Jump table.
+
+        .addr   INSTALL
+        .addr   UNINSTALL
+        .addr   HIDE
+        .addr   SHOW
+        .addr   BOX
+        .addr   MOVE
+        .addr   BUTTONS
+        .addr   POS
+        .addr   INFO
+        .addr   IOCTL
+        .addr   IRQ
+
+; Data that is visible to the outside. Initialized by the kernel.
+
+XPos:   .word   0                       ; Current mouse position, X
+YPos:   .word   0                       ; Current mouse position, Y
+
+; Callback table, set by the kernel before INSTALL is called
+
+CHIDE:  jmp     $0000                   ; Hide the cursor
+CSHOW:  jmp     $0000                   ; Show the cursor
+CMOVEX: jmp     $0000                   ; Move the cursor to X coord
+CMOVEY: jmp     $0000                   ; Move the cursor to Y coord
+
+
+;----------------------------------------------------------------------------
+; Constants
+
+SCREEN_HEIGHT   = 200
+SCREEN_WIDTH    = 320
+
+;----------------------------------------------------------------------------
+;
+; Global variables
+;
+
+.bss
+
+Vars:
+OldPotX:   	.res   	1	     	; Old hw counter values
+OldPotY:	.res   	1
+
+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
+
+OldValue:	.res   	1	     	; Temp for MoveCheck routine
+NewValue:	.res   	1	     	; Temp for MoveCheck routine
+
+; Default values for above variables
+
+.rodata
+
+.proc   DefVars
+        .byte   0, 0                    ; OldPotX/OldPotY
+        .word   0, 0                    ; XMin/YMin
+        .word   SCREEN_WIDTH            ; XMax
+        .word   SCREEN_HEIGHT           ; YMax
+.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
+
+; Done, return zero (= MOUSE_ERR_OK)
+
+        inx                             ; X = 0
+        txa
+;       rts                             ; Run into UNINSTALL instead
+
+;----------------------------------------------------------------------------
+; UNINSTALL routine. Is called before the driver is removed from memory.
+; No return code required (the driver is removed from memory on return).
+
+UNINSTALL:
+        rts
+
+;----------------------------------------------------------------------------
+; 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    = CHIDE
+
+;----------------------------------------------------------------------------
+; 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    = CSHOW
+
+;----------------------------------------------------------------------------
+; BOX: Set the mouse bounding box. 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.
+
+BOX:
+       	rts
+
+;----------------------------------------------------------------------------
+; MOVE: Move the mouse to a new position which is passed in X=ptr1, Y=a/x.
+; No checks are done if the new position is valid (within the bounding box or
+; the screen). No return code required.
+;
+
+MOVE:   sei                             ; No interrupts
+
+        sta     YPos
+        stx     YPos+1                  ; New Y position
+        jsr     CMOVEY                  ; Set it
+
+        lda     ptr1
+        ldx     ptr1+1
+        sta     XPos
+        stx     XPos+1                  ; New X position
+
+        jsr     CMOVEX			; Move the cursor
+
+	cli                             ; Allow interrupts
+       	rts
+
+;----------------------------------------------------------------------------
+; 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
+        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
+
+	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
+	cli	    			; Enable interrupts
+
+        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
+
+    	jsr     BUTTONS                 ; Will not touch ptr1
+    	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).
+;
+
+IRQ:    lda	SID_ADConv1		; Get mouse X movement
+      	ldy	OldPotX
+      	jsr	MoveCheck  		; Calculate movement vector
+      	sty	OldPotX
+
+; Skip processing if nothing has changed
+
+        tay
+        beq     @SkipX
+
+; Calculate the new X coordinate (--> a/y)
+
+       	add	XPos
+      	tay	      			; Remember low byte
+      	txa
+      	adc	XPos+1
+    	tax
+
+; Limit the X coordinate to the bounding box
+
+   	cpy	XMin
+   	sbc	XMin+1
+   	bpl	@L1
+       	ldy    	XMin
+       	ldx	XMin+1
+    	jmp	@L2
+@L1:	txa
+
+    	cpy	XMax
+    	sbc	XMax+1
+    	bmi	@L2
+    	ldy	XMax
+    	ldx	XMax+1
+@L2:	sty	XPos
+   	stx	XPos+1
+
+; Move the mouse pointer to the new X pos
+
+        tya
+        jsr     CMOVEY
+
+; Calculate the Y movement vector
+
+@SkipX: lda	SID_ADConv2	 	; Get mouse Y movement
+	ldy	OldPotY
+	jsr	MoveCheck	 	; Calculate movement
+	sty	OldPotY
+
+; Skip processing if nothing has changed
+
+        tay
+        beq     @SkipY
+
+; Calculate the new Y coordinate (--> a/y)
+
+      	sta	OldValue
+      	lda	YPos
+      	sub	OldValue
+      	tay
+      	stx	OldValue
+      	lda	YPos+1
+      	sbc	OldValue
+      	tax
+
+; Limit the Y coordinate to the bounding box
+
+   	cpy	YMin
+	sbc	YMin+1
+	bpl	@L3
+       	ldy    	YMin
+       	ldx	YMin+1
+    	jmp	@L4
+@L3:	txa
+
+    	cpy	YMax
+    	sbc	YMax+1
+    	bmi	@L4
+    	ldy	YMax
+    	ldx	YMax+1
+@L4:	sty	YPos
+	stx	YPos+1
+
+; Move the mouse pointer to the new X pos
+
+        tya
+        jsr     CMOVEX
+
+; Done
+
+@SkipY: rts
+
+; --------------------------------------------------------------------------
+;
+; Move check routine, called for both coordinates.
+;
+; Entry:   	y = old value of pot register
+;     	   	a = current value of pot register
+; Exit:	   	y = value to use for old value
+;     	   	x/a = delta value for position
+;
+
+MoveCheck:
+      	sty	OldValue
+      	sta	NewValue
+      	ldx 	#$00
+
+      	sub	OldValue		; a = mod64 (new - old)
+      	and	#%01111111
+      	cmp	#%01000000		; if (a > 0)
+      	bcs	@L1 			;
+      	lsr	a   			;   a /= 2;
+      	beq	@L2 			;   if (a != 0)
+      	ldy   	NewValue     		;     y = NewValue
+      	rts   	    			;   return
+
+@L1:  	ora   	#%11000000		; else or in high order bits
+      	cmp   	#$FF			; if (a != -1)
+      	beq   	@L2
+      	sec
+      	ror   	a   			;   a /= 2
+       	dex				;   high byte = -1 (X = $FF)
+      	ldy   	NewValue
+      	rts
+
+@L2:   	txa				; A = $00
+      	rts
+

libsrc/c64/mcbdefault.s

@@ -0,0 +1,103 @@
+;
+; Default mouse callbacks for the C64
+;
+; Ullrich von Bassewitz, 2004-03-20
+;
+
+        .export         _mouse_def_callbacks
+
+        .include        "mouse-kernel.inc"
+        .include        "c64.inc"
+
+
+; 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
+
+.proc   hide
+
+        lda     #MOUSE_SPR_NMASK
+        sei
+        and     VIC_SPR_ENA
+        sta     VIC_SPR_ENA
+        cli
+        rts
+
+.endproc
+
+; --------------------------------------------------------------------------
+; Show the mouse pointer
+
+.proc   show
+
+        lda     #MOUSE_SPR_MASK
+        sei
+        ora     VIC_SPR_ENA
+        sta     VIC_SPR_ENA
+        cli
+        rts
+
+.endproc
+
+; --------------------------------------------------------------------------
+; Move the mouse pointer X position to the value in a/x
+
+.proc   movex
+
+; Set the low byte, this frees A
+
+        sta     VIC_SPR_X
+
+; Set the high byte
+
+        txa                             ; Test high byte of X coord
+        bne     @L1
+        sei
+   	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
+        cli
+        rts
+
+@L1:    sei
+   	lda	VIC_SPR_HI_X   		; Get high X bits of all sprites
+   	ora     #MOUSE_SPR_NMASK        ; Set high bit for sprite
+        sta     VIC_SPR_HI_X
+        cli
+        rts
+
+.endproc
+
+; --------------------------------------------------------------------------
+; Move the mouse pointer Y position to the value in a/x
+
+.proc   movey
+
+       	sta    	VIC_SPR_Y               ; Set Y position
+        rts
+
+.endproc
+
+; --------------------------------------------------------------------------
+; Callback structure
+
+.rodata
+
+_mouse_def_callbacks:
+        .addr   hide
+        .addr   show
+        .addr   movex
+        .addr   movey
+
+
+

libsrc/mouse/Makefile

@@ -24,7 +24,8 @@ S_OBJS =        mouse-kernel.o  \
                 mouse_info.o    \
                 mouse_ioctl.o   \
                 mouse_pos.o     \
-                mouse_show.o
+                mouse_show.o    \
+                mouse_unload.o
 
 #--------------------------------------------------------------------------
 # Targets

libsrc/mouse/mouse-kernel.s

@@ -4,8 +4,8 @@
 ; Common functions of the mouse driver API.
 ;
 
-        .import         return0
+        .import         return0, popsreg, incsp2
-        .importzp       ptr1
+        .importzp       sreg, ptr1, tmp1, tmp2
        	.condes	       	mouse_irq, 2		; Export as IRQ handler
 
         .include        "mouse-kernel.inc"
@@ -42,15 +42,14 @@ mouse_sig:      .byte   $6d, $6f, $75, MOUSE_API_VERSION    ; "mou", version
 
 
 ;----------------------------------------------------------------------------
-; unsigned char __fastcall__ mouse_install (void* driver);
+; unsigned char __fastcall__ mouse_install (const struct mouse_callbacks* c,
+;                                           void* driver);
 ; /* Install an already loaded driver. Returns an error code. */
 
-
-
 _mouse_install:
        	sta     _mouse_drv
   	sta	ptr1
-  	stx     _mouse_drv+1
+   	stx     _mouse_drv+1
   	stx    	ptr1+1
 
 ; Check the driver signature
@@ -72,34 +71,62 @@ _mouse_install:
         ldy     #MOUSE_HDR::JUMPTAB
         ldx     #0
 @L1:    inx                             ; Skip the JMP opcode
-        jsr     copy                    ; Copy one byte
+        jsr     copyjv                  ; Copy one byte
-        jsr     copy                    ; Copy one byte
+        jsr     copyjv                  ; Copy one byte
         cpy     #(MOUSE_HDR::JUMPTAB + .sizeof(MOUSE_HDR::JUMPTAB))
         bne     @L1
 
-        jsr     mouse_install           ; Call driver install routine
+; Copy the callback vectors into the driver space
+
+        jsr     popsreg
+        ldy     #(MOUSE_HDR::CALLBACKS + .sizeof(MOUSE_HDR::CALLBACKS) - 1)
+        sty     tmp2
+        ldy     #.sizeof(MOUSE_CALLBACKS)-1
+        sty     tmp1
+
+@L2:    jsr     copycb
+        jsr     copycb
+        dec     tmp2                    ; Skip opcode byte
+        ldy     tmp1
+        bpl     @L2
+
+; Call driver install routine
+
+        jsr     mouse_install
+
+; Install the IRQ vector if the driver needs it. A/X contains the error code
+; from mouse_install, so don't use it.
 
         ldy     mouse_irq+2             ; Check high byte of IRQ vector
-        beq     @L2                     ; Jump if vector invalid
+        beq     @L3                     ; Jump if vector invalid
-	ldy	#$4C			; Jump opcode
+   	ldy	#$4C			; Jump opcode
        	sty    	mouse_irq               ; Activate IRQ routine
-@L2:    rts
+@L3:    rts
 
-; Driver signature invalid
+; Driver signature invalid. One word is still on the stack
 
 inv_drv:
         lda     #MOUSE_ERR_INV_DRIVER
         ldx     #0
-        rts
+        jmp     incsp2
 
 ; Copy one byte from the jump vectors
 
-copy:   lda     (ptr1),y
+copyjv: lda     (ptr1),y
         sta     mouse_vectors,x
         iny
         inx
         rts
 
+; Copy one byte from the callback vectors
+
+copycb: lda     (sreg),y
+        dec     tmp1
+        ldy     tmp2
+        sta     (ptr1),y
+        dec     tmp2
+        rts
+
 ;----------------------------------------------------------------------------
 ; unsigned char __fastcall__ mouse_uninstall (void);
 ; /* Uninstall the currently loaded driver. Returns an error code. */

libsrc/mouse/mouse_load.c

@@ -42,7 +42,13 @@
 
 
 
-unsigned char __fastcall__ mouse_load_driver (const char* name)
+/* Use static local variables, since the module is not reentrant anyway */
+#pragma staticlocals (on);
+
+
+
+unsigned char __fastcall__ mouse_load_driver (const struct mouse_callbacks* c,
+                                              const char* name)
 /* Load a mouse driver and return an error code */
 {
     static struct mod_ctrl ctrl = {
@@ -69,7 +75,7 @@ unsigned char __fastcall__ mouse_load_driver (const char* name)
         if (Res == MLOAD_OK) {
 
             /* Check the driver signature, install the driver */
-            return mouse_install (ctrl.module);
+            return mouse_install (c, ctrl.module);
 
         }
     }

libsrc/mouse/mouse_unload.s

@@ -0,0 +1,35 @@
+;
+; Ullrich von Bassewitz, 2004-03-21
+;
+; unsigned char __fastcall__ mouse_unload (void);
+; /* Uninstall, then unload the currently loaded driver. */
+
+
+        .import         mouse_clear_ptr
+
+        .include        "mouse-kernel.inc"
+        .include        "modload.inc"
+
+
+_mouse_unload:
+      	lda	_mouse_drv
+	ora	_mouse_drv+1
+       	beq    	no_driver		; No driver
+
+	lda	_mouse_drv
+	pha
+	lda	_mouse_drv+1
+	pha	      			; Save pointer to driver
+
+       	jsr    	_mouse_uninstall        ; Uninstall the driver
+
+	pla
+	tax
+	pla				; Get pointer to driver
+        jmp	_mod_free               ; Free the driver
+
+no_driver:
+       	tax				; X = 0
+	lda	#<MOUSE_ERR_NO_DRIVER
+	rts
+