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:
Nov. 09, 1999
Filed:
Jun. 11, 1997
Cheng-Yen Huang, Hsinchu, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A sequential memory access circuit for access to various memory units is provided. The sequential memory access circuit is coupled between an external system and at least two memory units including a RAM unit and a ROM unit. The sequential memory access circuit includes a common data pointer circuit, responsive to a reset signal, a write request signal, and a read request signal from said external system, for generating accordingly a RAM enable signal, a ROM enable signal, and a counter signal, for control of the access to the RAM unit and the ROM unit. Further, a length register is used to generate a bound control signal to said common data pointer circuit in response to the write request signal and the counter signal. A sequential access dedicated comparator is used to provide the controls for the access to the two memory units. The structure of the sequential memory access circuit allows for a small circuit layout area and a reduced delay time.