05686920 is referenced by 117 patents and cites 26 patents.

A method and system is provided for communicating permanent or semi-permanent information to a transponder (14) from an interrogator (12), preferably operated by a toll agency or other authorized entity. This permanent or semi-permanent information is communicated by means of special instructions valid only during a special mode or maintenance mode which is entered by transmitting a special access code to the transponder (14) from the authorized interrogator (12). The transponder (14) will preferably acknowledge to the authorized interrogator (12) that it is, in fact, operating in the maintenance mode so the interrogator (12) can transmit the special instructions in confidence.

Title
Transponder maintenance mode method
Application Number
233169
Publication Number
5686920
Application Date
June 7, 1995
Publication Date
November 11, 1997
Inventor
Francis B Frazee
Plano
TX, US
Dwaine S Hurta
Garland
TX, US
Agent
Richard L Donaldson
James C Kesterson
Rebecca A Mapstone
Assignee
Texas Instruments Incorporated
TX, US
IPC
G08B 1/123
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