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:
May. 27, 1997
Filed:
Nov. 21, 1994
Gary J Morse, Boca Raton, FL (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A video random access memory is disclosed that performs a block write function for an opaque pattern color expansion. The video RAM, or VRAM, uses an input buffer for receiving and holding video input information. A first color register is coupled to the input buffer and holds a first color value. A second color register coupled to the input buffer is used to hold a second color value. A gate multiplexor couples to both first color register and the second color register with a color selection register being used to gate which color value from the first color register or the second color register should be asserted. A write control logic selects which color values are to be displayed. A third or mask register is coupled to the input buffer and the write control logic such that, based upon data from the input buffer, the mask register selects which pixel location is to be changed based on the color value selected by the color selection register as received from the write control logic.