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.

Date of Patent:
May. 20, 2008

Filed:

Jun. 11, 2003
Applicants:

Naoki Mitsuishi, Kodaira, JP;

Shinichi Shibahara, Kodaira, JP;

Takahiro Okubo, Hanno, JP;

Inventors:

Naoki Mitsuishi, Kodaira, JP;

Shinichi Shibahara, Kodaira, JP;

Takahiro Okubo, Hanno, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F 9/30 (2006.01); G06F 9/40 (2006.01); G06F 15/00 (2006.01); G06F 7/38 (2006.01); G06F 9/00 (2006.01); G06F 9/44 (2006.01);
U.S. Cl.
CPC ...
Abstract

An apparatus and method for selecting whether a central processing unit (CPU) performs instruction reading in units of 16 bits (a first word length) or in units of 32 bits (a second word length). Depending on whether instruction reading is performed in units of 16 bits or 32 bits, increment values (+2 and +4) by which a program counter (PC) is incremented are switched. Data reading or writing is performed in units of a given data length irrespective of the selecting unit. When the CPU issues a request for instruction reading in units of 16 bits or 32 bits or for data reading or writing, a bus control unit performs reading or writing a predetermined number of times according to a bus width designated for a resource located at an address specified in the request.


Find Patent Forward Citations

Loading…