Abstract: There is described a decryption processing apparatus and an image forming apparatus, which make it possible to prevent the encrypted data from being incorrectly decrypted by employing a wrong decryption key. The decryption processing apparatus for decrypting encrypted digital data including encrypted code and encrypted data, includes: a first decryption section to generate decrypted diagnosis code by decrypting the encrypted code; a second decryption section to decrypt the encrypted data; a determination section to determine based on the diagnosis code whether a decryption process of the encrypted code is normally executed; and a control section to allow starting decryption process of the encrypted data by the second decryption section when the decryption process of the encrypted code is normal, and to prohibit starting the decryption process of the encrypted data by the second decryption section when the decryption process of the encrypted code is abnormal.

Abstract: An information processing apparatus for managing data of a plurality of modes such as schedule and address book, includes a RAM which has a data contents area for storing the contents of data, and a data address area for storing addresses where the respective data are stored in the data contents area while grouping the addresses according to mode.

Abstract: An information processing apparatus with a bookmark function includes a memory, a display section, and a CPU for placing a bookmark in data, which are stored in the memory in a plurality of modes, respectively, storing specific information for specifying data marked with the bookmark in the memory, retrieving the stored data with the bookmark based on the specific information, and displaying the retrieved data in the display section. When the stored data marked with the bookmark is retrieved based on the specific information, the CPU controls the display section to display the retrieved data and a mode to which the retrieved data belongs. This structure enables the user to use the apparatus more conveniently.

Abstract: Depiction of graphics which are displayed in combination with function graphs is accelerated. Graphics to be displayed on a display device in combination with function graphs are selected and drawn according to the graphic information stored in the graphic information storage area of the data storage RAM memory. The selection is executed based on whether the rectangular region of interest is even partially within the region to be displayed on the screen. The selected graphics are written to the display RAM as bit images by a CPU which operates under the direction of programs set in the program ROM, and displayed on a display device. The data in the graphic information storage area is displayed on a display device upon pressing an EDIT MODE key, edited by operation with an EDIT key, DELETE key, character keys, etc., and the display device is switched to the graphic screen with the modified graphic thereon, upon repressing the EDIT MODE key.

Abstract: In a feed screw device according to the present invention, a coil member is disposed on the outer periphery of a rotary shaft member. The coil member is formed of an elastic body such as a piece of piano wire. The coil member is mounted at least partially on the shaft member so as to have at least a portion remaining in a free state. The coil member is used to engage a nut placed on the outer periphery of the shaft member. When the shaft member is rotated, the coil member is also rotated together with the shaft member, so that the nut is moved in the axial direction of the feed screw. When the nut is brought into contact with a stopper by a driving force, the nut impactively strikes the stopper. However, since the coil member can be elastically deformed in the axial direction, the coil member is elastically deformed to absorb its impact. Also the "spring back" effect enabled by the deformable coil member serves as a contribution to the initiation of movement of the nut in the reverse direction.