05226122 is referenced by 102 patents and cites 32 patents.

A system utilizes one or more programmable logic arrays or gate arrays for regulating the commands available to a microprocessor, and intercepting certain of those commands according to predetermined citeria. The system selects and processes designated commands relating to the FORCE-A20 signal and CPU-RESET signal for a keyboard controller functionally attached to an INTEL 80286 or 80386 microprocessor. The system includes one or more programmable logic arrays or gate arrays for allowing all input commands to pass directly through to the keyboard controller except the command sequence relating to the FORCE-A20 signal or the CPU-RESET signal.

Title
Programmable logic system for filtering commands to a microprocessor
Application Number
7/88093
Publication Number
5226122
Application Date
August 21, 1987
Publication Date
July 6, 1993
Inventor
Montgomery C McGraw
Spring
TX, US
John S Thayer
Spring
TX, US
Agent
Vinson & Elkins
Assignee
Compaq Computer
TX, US
IPC
G06F 15/16
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