05084871 is referenced by 75 patents and cites 57 patents.

A computer interconnect coupler has channel transmitters and logic and channel receivers and logic circuitry for the routing of messages from the channel receivers which are addressed to the channel transmitters. When a message is received by a channel receiver, the channel receiver stores the beginning portion of the message in a first-in-first-out buffer, and sends a route message request to central switch logic. If the destination transmitter or receiver is busy, the central logic places the message request on a destination queue and returns a signal to the requesting source transmitter to turn on a flow control signal which is transmitted back to the data processing device having originated the message. Any message addressed to this data processing device, however, is inserted into the flow control carrier with pauses both before and after the message, and provisions are also made to allow the data processing device to return an ackowledgement responsive to the incoming message. To permit incremental expansion of the coupler to accommodate an increased number of channels, additional channel interface boards may be added. The coupler also includes a plurality of timers which determine fault conditions, and a diagnostic processor monitors the timers and associated error flags to diagnose faults to the board level. The conditions existing at the time of fault diagnosis are written into a non-volatile memory located on the circuit board. Therefore, the information is physically carried along with the board to the repair facility.

Title
Flow control of messages in a local area network
Application Number
110513
Publication Number
5084871
Application Date
October 3, 1989
Publication Date
January 28, 1992
Inventor
Milton V Mills
Boston
MA, US
Charles E Kaczor
Dudley
MA, US
Barry A Henry
Penacook
NH, US
Harold A Read
Burlin
MA, US
Allan R Kent
Arlington
MA, US
Robert C Kirk
Boylston
MA, US
Steven P Zagame
Boylston
MA, US
Donald R Metz
Ashburnham
MA, US
Ronald C Carn
Millis
MA, US
Agent
Arnold White & Durkee
Assignee
Digital Equipment Corporation
MA, US
IPC
H04L 12/44
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