Hitachi, Ltd.

Junichi Enomoto

Seiji Kageyama

Hiroshi Kanai

Seiichi Hayashi

Kazuo Kikuchi

Yousuke Nagano

Masayoshi Sunada

Takeo Sonobe

Yuichi Horiuchi

Hitoshi Ishida

Katsufumi Takagishi

Tomohiko Yanagita

Yasumasa Saito

Toshiaki Suematsu

Tetsuro Hatakeyama

Shinji Mizunuma

Kazuei Saito

A character generating system drives a printer engine to print characters in response to an instruction from a host computer. The characters to be printed by the printer information are normally generated on the basis of dot data stored in a cache memory via a print map memory under the control of e.g. a microprocessor. Since the cache memory is a volatile memory, its contents may be erased due to disconnetion of the power supply. In order to speed up the regeneration of the dot data in the cache memory, information relating to the dot data is stored in a non-volatile memory, and on reconnection of the power supply, that information is used together with vector information in a vector memory for regeneration of the dot data in the cache memory.

Character generation

In a controller for use in a printer, when line pitch information is set in a printer status storage unit by way of a line pitch setter, a distance setter determines a cursor/base line distance on the basis of the line pitch information, and a character pattern expander determines a base line from the cursor/base line distance, expands a dot pattern of a printing character in reference to the base line position and stores the expanded dot pattern in a buffer memory.

Printer with character expansion in accordance with line pitch

An alignment disk having an adjust signal recorded thereon to maintain data interchangeability of a magnetic disk drive apparatus and loadable and unloadable to and from the magnetic disk drive apparatus, and method and apparatus for verifying a tracking errors of the magnetic disk drive apparatus are disclosed; the magnetic disk drive apparatus including magnetic head means for recording and reproducing data on and from a magnetic recording medium, a head carriage for carrying the magnetic head means, and drive means for driving the head carriage radially of a track of the magnetic recording medium; the alignment disk having a set of track diameter adjust signal pairs recorded on tracks equal to or larger in number than the number of phases of a stepping motor for driving the head carriage and corresponding to at least the excitation phases of the stepping motor; the set of track diameter adjust signal pairs each having an inner track signal and an outer track signal extending inward and outward from a center of the track; and the set of track diameter adjust signal pairs being arranged symmetrically about a rotation axis of the disk.

Alignment disk for magnetic disk driving apparatus and method and

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Hitachi, Japan

Junichi Enomoto