Patents by Inventor Robert W. Fredrickson

Robert W. Fredrickson has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5131080
    Abstract: A graphics system uses a programmable tile size shape supported by a frame buffer memory organization wherein (X, Y) pixel addresses map into regularly offset permutations on groups of RAM address and data line assignments. This allows one RAM in each group to be accessed with a memory cycle in unison with one RAM in each other group, up to the number of groups. During such a memory cycle each RAM can receive a different address. A tile is the collection of pixel locations associated with a collection of addresses sent to the RAM's. Because of the regular nature of the permutations these locations may be regions bounded by a single boundary that may be rectangular and of varying size and shape. Changing the mapping of (X, Y) pixel addresses to RAM addresses for the groups changes the size and shape of the tiles. Tiles are cached. Tiles for RGB pixel are cached in an RGB cache, while Z values are cached in a separate cache.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: July 14, 1992
    Assignee: Hewlett-Packard Company
    Inventors: Robert W. Fredrickson, Andrew C. Goris
  • Patent number: 4961153
    Abstract: A graphics system uses a programmable tile size and shape supported by a frame buffer memory organization wherein (X, Y) pixel addresses map into regularly offset permutations on groups of RAM address and data line assignments. This allows one RAM in each group to be accessed with a memory cycle in unison with one RAM in each other group, up to the number of groups. During such a memory cycle each RAM can receive a different address. A tile is the collection of pixel locations associated with a collection of addresses sent to the RAM's. Because of the regular nature of the permutations these locations may be regions bounded by a single boundary that may be rectangular and of varying size and shape. Changing the mapping of (X, Y) pixel addresses to RAM addresses for the groups changes the size and shape of the tiles. Tiles are cached. Tiles for RGB pixel values are cached in an RGB cache, while Z values are cached in a separate cache.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: October 2, 1990
    Assignee: Hewlett Packard Company
    Inventors: Robert W. Fredrickson, Andrew C. Goris
  • Patent number: 4958302
    Abstract: A graphics system uses a programmable tile size and shape supported by a frame buffer memory organization wherein (X, Y) pixel addresses map into regularly offset permutations on groups of RAM address and data line assignments. This allows one RAM in each group to be accessed with a memory cycle in unison with one RAM in each other group, up to the number of groups. During such a memory cycle each RAM can receive a different address. A tile is the collection of pixel locations associated with a collection of addresses sent to the RAM's. Because of the regular nature of the permutations these locations may be regions bounded by a single boundary that may be rectangular and of varying size and shape. Changing the mapping of (X, Y) pixel addresses to RAM addresses for the groups changes the size and shape of the tiles. Tiles are cached. Tiles for RGB pixel values are cached in an RGB cache, while Z values are cached in a separated cache.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: September 18, 1990
    Assignee: Hewlett-Packard Company
    Inventors: Robert W. Fredrickson, Monish S. Shah
  • Patent number: 4367465
    Abstract: A graphics system for a raster scan CRT implements a light pen tracked by a cursor. Hits corresponding to the cursor are distinguished from those corresponding to background data by a selective interlacing technique. A threshold level shifting technique providing accurate measurement of a horizontal component of the cursor allows accurate prediction of the location of the center of the field of view during the next frame.
    Type: Grant
    Filed: April 4, 1980
    Date of Patent: January 4, 1983
    Assignee: Hewlett-Packard Company
    Inventors: Nicholas P. Mati, Frederick J. Porter, Robert W. Fredrickson