Added a driver to the CBM510 library that lets a joystick pretend to be a mouse.

libsrc/cbm510/mouseref.s

@@ -0,0 +1,23 @@
+;
+; Pointer for library references by device drivers.
+;
+; 2013-07-25, Greg King
+;
+
+        .export         mouse_libref, _pen_adjuster
+
+        .data
+
+mouse_libref:                   ; generic label for mouse-kernel
+
+; A program optionally can set this pointer to a function that gives
+; a calibration value to a driver.  If this pointer isn't NULL,
+; then a driver that wants a value can call that function.
+;
+; The function might read a value from a file; or, it might ask the user
+; to help calibrate the driver.
+;
+; void __fastcall__ (*pen_adjuster)(unsigned char *) = NULL;
+;
+_pen_adjuster:
+        .addr   $0000