Abstract: A means for preserve cache consistency is provided for a system comprising a central processing unit, a first physical memory, a second physical memory for which the address is common to the first physical memory in at least some duplicated address range of the entire physical address, a cache memory, and a memory controller, wherein the first or second physical memory is selected depending on the operation mode. Flag bits are provided in a tag memory of the cache for information identifying the data source. The cache then does not determine a cache hit/miss only based on whether data related to a CPU requested address exists in the cache, but determines whether the source of data requested by the CPU is consistent with the source of data stored in the cache by taking into account information on the operation mode simultaneously sent from the CPU. A cache hit is determined only when such two conditions are met.

Abstract: Photosensors having light emitting elements and light receiving elements are provided in a path for carrying a film. The light emitting elements emit periodic pulsed light. When the film is present in the positions of the photosensors, the periodic pulsed light is reflected by the film to enter the light receiving elements, whereby presence of the film is detected. Activation time and activation interval of the light emitting elements for generating the periodic pulsed light are determined so that accumulated exposure value in each portion on the film is less than a critical exposure value of photosensitive material provided in the film.

Abstract: A copying machine has a camera unit and a developer unit connected through a coupler, wherein the coupler includes feed paths along which a length of film is fed before and after exposure to a focused image of an original; a film cassette located adjacent to the feed path; a film carrier for supplying a length of unexposed film to the photographic or camera section, the film carrier being capable of running to and fro along a portion of the feed paths; an overlay sheet holder provided in opposite to the film carrier and movable in synchronism therewith; a transparent platen on which the film is placed with an overlay sheet covered thereon to shut out extraneous light; and a film sucking means mounted on the film carrier whereby a length of film after exposure is fed to the developer unit by being held by suction at its terminating end.

Abstract: An apparatus for locating a carrier, such as a lens carrier in a process camera unit, exactly at a desired position, the apparatus collecting data of the inertia acting upon the driving system including a motor and a shifting means, and obtaining a mean value from the collected measured values so as to correct the data of inertia in the driving system with the mean value. From the corrected data of inertia an information about the control of the driving system is derived, and applied to locate the carrier at a desired position.