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:
Jul. 11, 1995
Filed:
Oct. 12, 1993
Miho Taniguchi, Tokyo, JP;
Isao Hasegawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a memory access control device for use in combination with request sources (A, B, C), a main memory (11), and an expanded memory (12), a request receiving port section (13) successively receives a plurality of input requests as received requests. Supplied with the received requests, a selecting circuit (14) selects one of the received requests as a selected request. Supplied with the selected request, a request judging circuit (15) judges a type of the selected request to produce a request type signal indicative of the type of the selected request. Responsive to the request type signal, a request processing section (16) processes the selected request. The input requests include an access request indicative of access to the main memory, a first data transfer request indicative of transfer of data from the main memory to the expanded memory, and a second data transfer request indicative of transfer of data from the expanded memory to the main memory. The input requests may include a diagnostic request indicative of detection of failure in the main memory.