04494114 is referenced by 152 patents and cites 11 patents.

A lock-out security arrangement for and method of maintaining microprocessor-controlled electronic equipment normally operational until the occurrence of a disabling event, such as physical removal of the equipment from its normal installation, and/or electrical removal of the equipment from a source of electrical power, and thereupon for disabling the equipment after detecting the disabling event and for maintaining the equipment disabled, even after the disabling event has been discontinued, until a code manually entered via a keyboard associated with a microprocessor for controlling the normal operation of the equipment matches a private access code whose identity is protected from external interrogation by reason of being stored in an internal non-volatile memory of the microprocessor. The private access code is preferably selected by and known only to the user, and may be changed to a different private access code at the user's option.

Title
Security arrangement for and method of rendering microprocessor-controlled electronic equipment inoperative after occurrence of disabling event
Application Number
6/558115
Publication Number
4494114
Application Date
December 5, 1983
Publication Date
January 15, 1985
Inventor
Norman Kaish
Whitestone
NY, US
Agent
Kirschstein Kirschstein Ottinger & Israel
Assignee
International Electronic Technology
NY, US
IPC
G06F 7/00
G08B 13/06
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