04231089 is referenced by 25 patents and cites 1 patents.

In a data processing system, a method and apparatus which enable an erroneous microinstruction word to be rewritten before it is executed. After the microinstruction word is written from memory into a control register, a parity network coupled to the control register determines whether a correct microinstruction is being executed. Upon a parity error being detected, the clock pulses to the data paths coupled to the control register are inhibited. The original microinstruction word is then fetched from secondary storage and rewritten into the microinstruction memory with the aid of a separate register providing the address to the microinstruction memory. Upon rewriting the microinstruction memory, the signal inhibiting the clock pulses is removed thereby allowing a new microinstruction to be executed. An additional feature includes apparatus for determining whether an error has previously occurred for the same microinstruction word, in which case a critical fault occurs and remedial maintenance is necessary.

Title
Data processing system with apparatus for correcting microinstruction errors
Application Number
5/969956
Publication Number
4231089
Application Date
December 15, 1978
Publication Date
October 28, 1980
Inventor
Ronald J Setera
Leominster
MA, US
Thomas M Dundon
Marlborough
MA, US
Donald A Lewine
Marlborough
MA, US
Agent
Cesari & McKenna
Assignee
Digital Equipment Corporation
MA, US
IPC
G06F 11/16
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