04534025 is referenced by 36 patents and cites 7 patents.

An improved serial data protocol/format is provided in a serial multiplex system for use in an automotive vehicle electrical system which is subject to electrical noise. The protocol/format includes successive transactions between a master controller and respective remote controllers each connected to a serial multiplex bus. Each transaction is bidirectional and includes a command message transmitted by the master controller and a reply message normally transmitted by an answering remote controller. Each command message is preceded by a multibit SYNC byte. The command message includes an address byte (for a particular remote controller), a command byte, and an error check such as a cyclic redundance check byte passed on the address and command bytes. The reply message includes the address byte of the replying remote controller, a response byte indicative of its response to the command byte, and an error check such as a cyclic redundancy check byte based on the reply address and response bytes. The master controller may be caused to repeat the transmission of a command message if the address bytes, the command/response correlations or error check bytes are not verifiable, thereby enhancing the system's ability to detect and/or reject errors as might be occasioned by noise.

Title
Vehicle multiplex system having protocol/format for secure communication transactions
Application Number
6/469591
Publication Number
4534025
Application Date
February 24, 1983
Publication Date
August 6, 1985
Inventor
William M Floyd
Livonia
MI, US
Agent
Stephen A Schneeberger
Assignee
United Technologies Automotive
MI, US
IPC
H04J 6/00
H04J 3/00
H04J 3/02
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