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:
Sep. 25, 1990
Filed:
Mar. 08, 1989
Gerald K Mercola, Pleasanton, CA (US);
Shih-Hsing Huang, San Jose, CA (US);
ICS Electronics Corporation, San Jose, CA (US);
Abstract
A bus extender and data transmission method in which a continuous train of message frames of fixed size is sent along a dual serial link in both directions simultaneously. There is no handshaking between extenders unless a transmission error is detected. Message frames are constructed at a rate which is independent of serial link length and the bus data transfer rate. Each extender is divided into a bus handshake layer which sends and receives data and signals from a local bus, a management layer which continuously constructs message frames, responds to commands and receives and decodes incoming messages from a remote extender, and a transport layer. The transport layer has shift registers and encoders to receive messages from the management layer and transmit them over the serial link and has a memory to store up to 30 messages in the event of a retransmission request. The transport layer also receives messages from the serial link, checks for valid error-free messages and sends them to the management layer. It also initiates a retransmission request in the event a transmission error is detected.