Abstract: A control information assigning method whereby control information can be accurately transmitted. Present control information and past control information are formed into a pair to be assigned to one transmission symbol, so that a prescribed restricted condition is applied to the transmission symbol. Thereby, an error correction capability can be added to the transmission symbol and thus, the control information can be accurately transmitted.

Abstract: An optical disc and a disc cartridge for accommodating the optical disc, wherein the disc cartridge accommodates a disc non-symmetrical in cross-section relative to the center of thickness of the disc. The disc cartridge includes a main cartridge body portion and an opening/closure mechanism, in which the main cartridge body portion has an aperture via which to insert or take out the disc. The main cartridge body portion is configured for accommodating the disc only in the regular state of the disc which permits recording and/or reproduction of the disc. The opening/closure mechanism opens or closes the aperture.

Abstract: A display microcomputer displays a menu corresponding to several functions, such as picture-in-picture display and satellite broadcast reception on a mini-viewing screen that is part of the cathode-ray tube picture screen of a television receiver. A remote controller permits selection of different video and audio signal sources and, if the user selects sources that are incompatible or inconsistent, a system controller returns the menu to the condition prior to the incorrect selection. The system controller also controls a display microcomputer in such a way that items on the menu that are inhibited from selection are displayed in halftone. That is, if any inhibited item appears in the menu by a modification of the mode of operation, the display microcomputer is controlled so that the menu is returned to the condition prior to the selection and the inhibited item is displayed in halftone.