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:
Sep. 19, 1989
Filed:
Jun. 03, 1987
Toyohiko Kagimasa, Hachiouji, JP;
Yoshiki Matsuda, Kokubunji, JP;
Kikuo Takahashi, Hachiouji, JP;
Seiichi Yoshizumi, Hino, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A data processor which specifies either of a predetermined maximum length of an adddress (a bits) and a length of an address less than the former length and at plural registers having a number of length of bits (r bits) of the maximum address length or greater. The data processor reads out lower-order d bits for data or r bits for an address of the one of the plural registers (7) specified by a first instruction to perform an arithmetic or logic operation, and writes the result into one of the plural registers. Moreover, the processor reads out bits having specified length of an address from the one of the plural registers specified in a second instruction to generate an a-bit address, and reads out d for data or r bits for an address from a main storage device (5) in response to the thus-generated address to write the d or r bits into one of the plural registers. Since the data length is consistently d bits irrespective of specified effective length of an address, direct data transfer is enabled between programs each having a different effective length of an address thereby facilitating extension of the length of a storage address and assuring compatibility with conventional data processors.