COMPUTER INTERCONNECT COUPLER FOR CLUSTERS OF DATA PROCESSING DEVICES

摘要

COMPUTER INTERCONNECT COUPLER FORCLUSTERS OF DATA PROCESSING DEVICESABSTRACTA computer interconnect coupler has channeltransmitters and channel receivers and logic circuitry forthe routing of messages from the channel receivers whichare addressed to the channel transmitters. When a messageis received by a channel receiver, the channel receiverstores the beginning portion of the message in a first-in-first-out buffer, and sends a route message request tocentral switch logic. If the destination transmitter orreceiver is busy, the central logic places the messagerequest on a destination queue and returns a signal to therequesting source transmitter to turn on a flow controlsignal which is transmitted back to the data processingdevice having originated the message. Any messageaddressed to this data processing device, however, isinserted into the flow control carrier with pauses bothbefore and after the messages and provisions are also madeto allow the data processing device to return anacknowledgment responsive to the incoming message. Topermit incremental expansion of the coupler to accommodatean increased number of channels, additional channelinterface boards may be added. The coupler also includesa plurality of timers which determine fault conditions,and a diagnostic processor monitors the timers andassociated error flags to diagnose faults to the boardlevel. The conditions existing at the time of faultdiagnosis are written into a non-volatile memory locatedon the circuit board. Therefore, the information isphysically carried along with the board to the repairfacility.