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:
Oct. 23, 1987
Yoshio Kawamata, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed is a raster operation device including a word boundary checking circuit which operates on a hardware basis to check as to whether the writing of data across the word boundary of frame buffer occurs, basing on the shift width, bit width, etc. of data to be written from CPU to frame buffer; an address generation circuit which operates on a hardware basis to provide the frame buffer with the next address adjacent in the word boundary direction to the address of frame buffer specified for writing by the CPU; and a sequence control circuit which operates on a hardware basis to control in read-modify-write mode the writing of data in the address specified by the CPU when the writing data is found not to cross the word boundary, or to control in read-modify-write mode the writing of data in the address specified by the CPU and, thereafter, control in read-modify-write mode the writing of bit data which has been left unwritten in the address specified by the CPU into the next address adjacent in the word boundary direction issued by the address generation circuit, basing on a single writing instruction issued by the CPU to the frame buffer.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile