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. 17, 1996
Filed:
May. 09, 1995
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
The invention provides an information processing apparatus which is equipped with PSRAM (pseudo static random access memory) having a self-refresh mode and which is capable of holding storage contents of the PSRAM even when a CPU system clock generator comes to an abnormal halt. The information processing apparatus has a self-refresh setter which produces an output signal of a high or low specific level when the system clock generator is oscillating, and which, when the system clock generator stops oscillation, inverts the level of the output signal after a certain time elapse since the stop of oscillation. The information processing apparatus further has logic circuits for holding a chip-enable signal at a level representing that the PSRAM is not accessed, and holding a refresh signal at a level representing that the PSRAM is refreshed, respectively, after a certain time elapse since the system clock generator stops oscillation, based on an output of the self-refresh setter.