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:
Oct. 31, 1995
Filed:
Aug. 04, 1993
Yoshihiro Saito, Itami, JP;
Yoshiaki Kittaka, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A memory control unit and associated method for changing memory access time are used in a microprocessor system in order to make it possible to alter the number of wait states in accordance with memory characteristics. The memory control unit incorporates a register which holds at least 1 bit of data related to the wait states, outputs a response signal to a central processing unit (CPU) at a timing changed in accordance with the data held in the register, and changes the data held in the register by executing a write cycle under control of the CPU. The memory control unit includes a section for holding fixed data representing a fixed delay time based upon an anticipated access time of a memory unit, in addition to the register which holds variable data representing a variable delay time, and an output circuit which adds the fixed data and variable data to produce data representing a total delay time.