[54] APPARATUS AND METHOD FOR UPDATING INFORMATION IN A MICROCODE INSTRUCTION
[75] Inventor: James T. C. Kaba, Jackson, N.J.
[73] Assignee: David Sarnoff Research Center, Inc., Princeton, N.J.
[21] Appl. No.: 402,311
[22] Filed: Mar. 10, 1995
Related U.S. Application Data
[63] Continuation of Ser. No. 228,482, Apr. 15, 1994, abandoned.
[51] Int. CI.6 G06F 9/24
[52] U.S. CI 395/567; 395/701; 395/477
[58] Field of Search 395/775, 375,
395/476, 477, 405
[56] References Cited
U.S. PATENT DOCUMENTS
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Primary Examiner—William M. Treat
Assistant Examiner—Viet Vu
Attorney, Agent, or Firm—William J. Burke
[57] ABSTRACT
In a computer for executing a computer program, apparatus and a method for updating information within a computer program instruction without interrupting execution of the computer program. The apparatus contains a memory for storing the information within the instruction at an address within the memory, circuitry for periodically accessing the information for execution by the computer, and circuitry for altering, between periodic accesses to the memory by the accessing circuitry, the information stored in the memory. In this manner, computer program execution is not interrupted to alter the information within the instruction. Typically, the information is a data field value contained within a computer microcode instruction. Consequently, the data field value is updated, but other information within the instruction such as an operational code (OPcode), is not altered by the update operation. The apparatus and method disclosed herein find applicability in video servers, medical imaging, special effects and animation and location based entertainment systems among other applications.
17 Claims, 3 Drawing Sheets
