The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 06, 1985
Filed:
Feb. 24, 1983
William M Floyd, Livonia, MI (US);
United Technologies Automotive, Inc., Dearborn, MI (US);
Abstract
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.