Abstract: A use limit system in which only contents users who have made a viewing contract can decrypt encrypted contents and use the contents.

Abstract: A master device in a system including a bidirectional bus and at least one device manages whether the system is in an access state in which the master device permits an access to or from one device or a non-access state in which the master device permits an access to none of the devices. The master device drives the bidirectional bus using a predetermined current to transfer data to or from one device connected to the bidirectional bus when the system is in the access state. When the state of the system changes from the access state to the non-access state, the master device drives the bidirectional bus in order to stabilize the potential of the bidirectional bus to keep the bus potential from changing when the system is in a non-access state, thereby eliminating the need for conventional pull-up/pull-down resistors for stabilizing the bus potential during a non-access state.

Abstract: A content reproduction apparatus functioning to (a) reproduce broadcast program content (“BC”), being image, sound, and other data, that has been received, (b) store commercial content (“CC”), being data such as commercials, announcements, and the like, and (c) cancel the reproduction of the CC during specified broadcast programs.

Abstract: A system integrated circuit prevents a storage region of confidential data that has been read from a memory device from being revealed by tracing the operation of an internal CPU. The confidential data is stored in a secondary memory and is used by the CPU. The confidential data is read from the secondary memory to a primary memory at initialization of an apparatus in which the system integrated circuit is incorporated. Specifically, an initial-state management unit (15) reads the confidential data from the memory devices (101 or 111), and stores it into one of storage regions in the primary memory at the initialization of the apparatus. The initial-state management unit (15) then instructs the CPU to start its operation. Even if thorough reverse analysis is performed on the operation of the CPU, the storage region of the confidential data is not revealed.

Abstract: The remote control signal reception controller receives control data transmitted from a remote control signal sender. The remote control signal reception controller informs a CPU that controls a device of the information on the received control data by interrupting the CPU. When doing so, the remote control signal reception controller judges whether a piece of control data that has just been received and a preceding piece of control data were consecutively transmitted, and whether these two pieces of control data are the same control data. The remote control signal reception controller interrupts the CPU only once when finding that the same control data is continuously transmitted as the result of this judgement.

Abstract: An apparatus and method for controlling data read access to memory, in response to an access request sent through a system bus. The apparatus includes an data storage device for preserving data corresponding to a predetermined address; a judging device for judging whether an access address indicated by the access request matches the predetermined address; and a control device for making the data storage device output data preserved therein to the system bus when the access address has been judged to match the predetermined address, and for making the data storage device hold data corresponding to a next address subsequent to the access address when the access address has been judged not to match the predetermined address.