Patents by Inventor Elbert A. Cheek

Elbert A. Cheek 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).

  • Data processing apparatus for address substitution
    Patent number: 4603399
    Abstract: Data from a patch memory (23) is substituted for that in a system ROM (9) by applying high order addresses to a standard PLA (19) having word lines (FIG. 3, 50a-50p). The address orders are separately applied to EXCLUSIVE OR circuits (27a-27g). The PLA (19) is personalized to activate line (21) at addresses to be substituted and to provide logical zeros to the EXCLUSIVE OR circuits (27a-27g) which change during the patch. Only one word line is required for each continuous patch, which vary in size on a patch-by-patch basis. The circuit is fast and efficient. It can be used for a wide variety of memory substitution applications.
    Type: Grant
    Filed: December 27, 1983
    Date of Patent: July 29, 1986
    Assignee: International Business Machines Corporation
    Inventors: Elbert A. Cheek, David R. Thomas, John D. Zbrozek