Abstract: A method and system for detecting an invalid access to a memory in a user program, in which an inaccessible area is set and a real memory area corresponding to the inaccessible area is obtained in response to a request for allocating a dynamic memory in a user program. In translating an address in the inaccessible area into an address in the real memory area with an address translation table, it is found whether or not the requested access is invalid.

Abstract: A disk storage device includes a head part for writing data to a storage disk inserted into the device and for reading data from the disk, an eject member which is operated when a disk cartridge containing the disk is ejected, a turntable for rotating and driving the disk thereon to perform data recording and reproducing with the head part, a holder for holding the disk cartridge containing the disk, the holder placing the disk at a read/write position on the turntable when the disk cartridge is inserted, a slider which is disconnected from a latch lever when the disk cartridge is inserted and is moved in a direction parallel to the direction of insertion of the disk cartridge so as to place the disk at the read/write position on the turntable, and a movement mechanism for moving the holder and the disk cartridge from the read/write position of the turntable to an insertion position in response to a movement of the slider in the direction opposite to the first direction when the eject member is operated.

Abstract: An electronic engraving and recording system comprising a television camera for picking up an image of an object and converting this image into an electrical signal, means for generating control signals on the basis of the synchronizing signal used in the television camera, memory means for storing the electrical signal under control of the control signals, means for engraving and recording the image according to the signal read out from the memory means under control of the control signals, and monitoring display means for displaying the visible image of the object in response to the application of the signal read out from the memory means. An image of an object can be simply engraved and recorded on a card within a short period of time without requiring any photographic original of the object.