Method and apparatus for controlling usage of a programmable computing machine

Patent 4246638 Issued on January 20, 1981. Estimated Expiration Date:

September 14, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3609697

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Inventor

Thomas, William J.

Application

No. 05/942422 filed on 09/14/1978

US Classes:

712/208, INSTRUCTION DECODING (E.G., BY MICROINSTRUCTION, START ADDRESS GENERATOR, HARDWIRED)714/699PULSE OR DATA ERROR HANDLING

Examiners

Primary: Atkinson, Charles E.

Attorney, Agent or Firm

Phillips, Moore, Weissenberger, Lempio & Majestic

International Classes

G06F 9/318 (20060101)
G06F 9/30 (20060101)
G06F 21/00 (20060101)

Abstract

A method for controlling usage of a programmable computing machine which operates in accordance with uncoded or published machine language operation codes including uniquely encoding the uncoded operation codes of instructions of a program to be used on the computing machine as a function of location of the instructions in memory and as a function of machine state, and adding to the machine a decoder that decodes only the uniquely encoded operation codes. Apparatus for controlling usage of a programmable computing machine which operates in response to uncoded or published machine language operation codes including memories which store machine user created programs and operating system programs, in which each program has instructions with uncoded and encoded operation codes, decoders to decode the encoded operation codes of the instructions of the user created program and the encoded operation codes of the instructions of the operating system program, and a circuit to execute the instructions of the user created program and the operating system program having the decoded and the uncoded operation codes.