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:
Mar. 04, 1997
Filed:
Aug. 26, 1994
Stephen C Purcell, Mountain View, CA (US);
David E Galbi, Santa Clara, CA (US);
Frank H Liao, Sunnyvale, CA (US);
Yvonne C Tse, Fremont, CA (US);
C-Cube Microsystems, Inc., Milpitas, CA (US);
Abstract
A 2-dimensional display space is mapped into the external DRAM addresses by embedding in the address space X and Y vectors of the display space. The mapping of the X and Y vectors allows a macroblock of pixels to be stored in one DRAM memory page, so that an access to a macroblock can be efficiently accomplished under a page mode access to the DRAM page. By providing control to one address bit, data of four pixels can be obtained at one time in one of 2 pixel.times.2 pixel 'quad pixel' configuration, or in a 4 pixel.times.1 pixel horizontal 'scan' configuration. In addition, a structure and a method are provided for accessing a 16.times.16-pixel picture area in two parts, in order that the number of DRAM page boundaries crossed during access of the 16.times.16-pixel picture area is minimized, thereby increasing the efficiency of memory access by reducing the overhead cost of initial accesses under page mode access to DRAMs.