A method is disclosed for providing interoperation of a first execution image of a first version and a second execution image of a second version. A compatibility matrix specifies whether the versions are compatible, base-level compatible, or incompatible. In one embodiment, the compatibility matrix may comprise a sparse table that stores a compatibility indicator for all permutations of a plurality of versions of a network operating system. As part of initialization of a system that includes the first execution image and second execution image, version information for the execution images is determined. An entry in the compatibility matrix corresponding to the versions is identified. The execution images are operated in a fully synchronized state when the identified entry of the compatibility matrix specifies that the versions are either compatible or base-level compatible. Individual components of the execution images interoperate according to the results of individual session negotiations. If the versions are incompatible, an alternative redundancy operation mode may be used. Embodiments provide for negotiation of compatible message versions and capabilities among peer components or clients of the execution images as source information to generate the compatibility matrix.

A pinball machine has been designed with several novel mechanical and electrical features such that it is easily updatable, or alternately, retrofittable or convertible between a first pinball game and a second pinball game. The pinball machine includes a cabinet, a playfield, a panel, an electronics system, and a video display. The playfield is mounted in the cabinet with the panel mounted to the cabinet and overlaying at least a portion of the playfield. The video display is mounted generally above the cabinet and is disposed to project video images onto the panel for viewing by the player. The electronics system includes a control unit and a plurality of input/output elements which are mounted to the playfield. The control unit, which includes a controller and memory for storing game instructions and video images, is coupled to the plurality of input/output elements. The controller executes the game instructions to cause the video images to be displayed upon the video display. The memory may include flash memory which can be updated by a flash card. A retrofitting kit for the pinball machine provides a replacement memory that stores second game instructions and second game video images therein for operation in the pinball machine. Thus, the types of video images of displayed by the pinball machine, the times the video images are displayed, and the manner in which they are displayed can be entirely modified. The kit may also include a new playfield to alter the physical environment which the rolling ball of the machine interacts to complement the new video images.

A pinball machine has been designed with several novel mechanical and electrical features such that it is easily retrofittable or convertible between a first pinball game and a second pinball game. The pinball machine includes a cabinet, a playfield, a panel, an electronics system, and a video display. The playfield is mounted in the cabinet with the panel mounted to the cabinet and overlaying at least a portion of the playfield. The video display is mounted generally above the cabinet and is disposed to project video images onto the panel for viewing by the player. The electronics system includes a control unit and a plurality of input/output elements which are mounted to the playfield. The control unit, which includes a controller and memory for storing game instructions and video images, is coupled to the plurality of input/output elements. The controller executes the game instructions to cause the video images to be displayed upon the video display. A retrofitting kit for the pinball machine provides a replacement memory that stores second game instructions and second game video images therein for operation in is the pinball machine. Thus, the types of video images of displayed by the pinball machine, the times the video images are displayed, and the manner in which they are displayed can be entirely modified. The kit may also include a new playfield to alter the physical environment which the rolling ball of the machine interacts to complement the new video images.

A pinball machine has been designed with several novel mechanical and electrical features such that it is easily retrofittable or convertible between a first pinball game and a second pinball game. The pinball machine includes a playfield mounted to a cabinet. Unlike previous pinball machines, electrical wires and their associated "playfield-side" connectors extending from input/output elements mounted to the playfield are limited in movement to a region generally beneath and in close proximity to the playfield. This allows the playfield to be more easily handled than prior playfields, which had long dangling electrical wires and connectors which could be easily tripped over or severed. Additionally, the plurality of playfield-side connectors are configured for easy installation and integration with corresponding "cabinet-side" connectors. The cabinet-side connectors are electrically connected to a driver electronics board mounted within the cabinet and carry all input/output functions of the driver electronics board.

A game which comprises a plurality of play devices and a panel for prohibiting access of a player to the plurality of play devices. The panel includes at least two optically distinct portions. A first optically distinct portion is substantially transparent for viewing at least one of the play devices and a second optically distinct portion is partially transparent for viewing at least another of the plurality of the play devices and partially reflective for reflecting a virtual image to be viewed by the player. The second optically distinct portion having a higher reflectivity than the first optically distinct portion.