The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 09, 1986
Filed:
May. 17, 1985
Kazuhiko Nishi, Tokyo, JP;
Takatoshi Ishii, Tokyo, JP;
Ryozo Yamashita, Tokyo, JP;
Shigemitsu Yamaoka, Hamamatsu, JP;
Takatoshi Okumura, Hamamatsu, JP;
Minoru Morimoto, Hamamatsu, JP;
Ascii Corporation, Tokyo, JP;
Nippon Gakki Seizo Kabushiki Kaisha, Hamamatsu, JP;
Abstract
A video display control system comprises a video display processor (VDP) which is capable of accessing to a video RAM (VRAM) at an extremely high-speed. The VRAM used in this system comprises first and second dynamic RAMs each having an address input terminal to which row address data and column address data are supplied, a row address strobe input terminal, a column address strobe input terminal, and a data input/output terminal. The row address data is latched at the leading edge of a row address strobe signal applied to the row address strobe input terminal, while the column address data is latched at the leading edge of a column address strobe signal applied to the column address strobe input terminal. An access to an address of each dynamic RAM is established when both of the row and column address data are latched. The VDP comprises a VRAM interface for controlling an access to the first and second dynamic RAMs which is connected to the RAMs through a common address bus. The VRAM interface first outputs row address data together with a row address strobe signal RAS and then outputs column address data together with two column address strobe signals CAS0 and CAS1 which are rendered active in sequence and supplied to the first and second dynamic RAMs, respectively.