<p>A matrix address decoder for rolling ball games performs decoding of a sequential identification number and a base address into an offset address corresponding to a memory location containing status information for playfield features or switches. The matrix address decoder also generates a mask byte for use in subsequent logical operations involving the status information contained in memory. The decoded information is returned to the main microprocessor via the system bus. An alternate function returns only the mask byte when the offset address is known by the main microprocessor.</p>