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:
Apr. 05, 1994
Filed:
Aug. 17, 1990
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A central processing unit includes a programmable logic array, a timing control unit, a predecoder, a data input/output part, and a processing part. The processing part carries out a predetermined operation on m-bit low-order data from among data which is composed of n bits and which is read out from a memory and m-bit high-order data from among the data composed of n bits, and outputs a carry signal when the predetermined operation on the m-bit low-order data results in a carry. When the operation code is a read modify write instruction and when the processing part outputs the carry signal, the programmable logic array controls the input/output part so that only the result of the predetermined operation on the m-bit low-order data is written into the memory.