Dual bus local area network interfacing system

• US 5,355,452 A
• Filed: 07/02/1992
• Issued: 10/11/1994
• Est. Priority Date: 07/02/1992
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Mathew, Brandon H., Lam, Roger T., Wakeley, Matthew P.
• Primary Examiner(s): MacDonald, Allen R.
• Assistant Examiner(s): Sheikh, Ayaz R.
• Application Number:
  US07/907,955
• Time in Patent Office: 831 Days
• Field of Search: 395/325, 395/250, 395/200, 395/275, 395/725, 370/85.1, 340/825.03
• US Class Current: 710/311
• CPC Class Codes: G06F 13/36 for access to common bus or bus system
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00

Abstract

An improved local area network interfacing system. The inventive system includes a frontplane circuit for connecting the interfacing system to a local area network and a backplane circuit for connecting the interfacing system to a host. A first internal bus is included for providing communication between the backplane circuit and the frontplane circuit. A processor is included for controlling the operation of the interfacing system. A second internal bus is included for providing communication between the processor and associated memory. An internal bus control circuit facilitates and controls communication between the first internal bus and the second internal bus. The dual internal busses of interfacing system of the present invention afford high speed operation with an inexpensive processor by allowing for input and output operations to be completed without being impeded by processor operations.

Claims

1. An interface system for providing an interface between a local area network and a host, said system comprising:

a first bus;

backplane controller means, connected to said first bus, for interfacing said first bus to said host;

a second bus;

frontplane controller means, connected to said first and second bus, for interfacing said local area network to said first bus and said second bus, respectfully;

processing means for controlling communication between said first bus and said second bus;

transceiver means, connecting said first bus to said second bus for allowing communication between said first bus and said second bus; and

midplane controller means connected to said second bus for allowing said processing means to determine the status of activity on said first bus by communicating directly with said midplane controller means.

2. The invention of claim 1 wherein said midplane controller means includes logic means for generating signals to allow the processor to access said first bus.

3. The invention of claim 2 wherein said logic means includes means for determining whether said frontplane controller means or said backplane controller means has control of said first bus.

4. The invention of claim 3 wherein said logic means includes means for generating a signal that indicates that communication between busses is permissible.

5. The invention of claim 4 wherein said logic means includes means for receiving an acknowledgement signal from said first bus.

6. The invention of claim 1 further including a first memory connected to said second bus.

7. The invention of claim 6 further including means for controlling data communication between the frontplane controller and the backplane controller.

8. The invention of claim 7 further including a second memory connected to said first bus.

9. The invention of claim 8 further including means connected to said second bus for permitting access to said interfacing system and managing traffic therethrough.

10. A system for providing an interface for a local area network with a host, said system comprising:

a first bus;

frontplane controller means connected to said first bus for interfacing said local area network to said first bus;

backplane controller means connected to said first bus for interfacing said first bus to said host;

status means connected to said first bus for generating signals indicative of the status of activity on said first bus;

a second bus;

transceiver means connected between said first bus and said second bus for interfacing said first bus to said second bus, said transceiver means including means for receiving signals from said status means indicative of the status of activity on said first bus;

a processor connected to said second bus; and

midplane controller means connected to said second bus for controlling said transceiver means to communicate said signals from said transceiver to said midplane controller means, said midplane controller means further including means responsive to said processor for communicating at least one of said signals from said midplane controller means to said processor and thereby communicate the status of activity on said first bus to said processor.