Computer interconnection system

• US 7,113,978 B2
• Filed: 01/22/2002
• Issued: 09/26/2006
• Est. Priority Date: 08/25/1995
• Status: Expired due to Fees

• Current Assignee: Avocent Redmond Corporation (Emerson Electric Company)
• Original Assignee: Avocent Redmond Corporation (Emerson Electric Company)
• Inventors: Lacrampe, Paul, Greene, Thomas, Huffington, James C., Hafer, Kevin J., Beasley, Danny L., Seifert, Robert V. Jr.
• Primary Examiner(s): Dinh, Dung C.
• Application Number:
  US09/683,582
• Publication Number:
  US 20020087753A1
• Time in Patent Office: 1,708 Days
• Field of Search: 709/208, 709/209, 709/210, 710/2, 710/38, 710/100, 710/316, 710/317, 345/700, 345/716, 345/704
• US Class Current: 709/208
• CPC Class Codes: G06F 13/4022 using switching circuits, e.g. switching matrix, connection or expansion network G06F13/4009 takes precedence
• CPC Class Codes: G06F 15/17375 One dimensional, e.g. linear array, ring
• CPC Class Codes: G06F 3/023 Arrangements for converting discrete items of information into a coded form, e.g. arrangements for interpreting keyboard generated codes as alphanumeric codes, operand codes or instruction codes
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/561 Adding application-functional data or data for application control, e.g. adding metadata
• CPC Class Codes: H04L 67/567 Integrating service provisioning from a plurality of service providers
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

A computerized switching system for coupling a workstation to a remotely located computer. A signal conditioning unit receives keyboard and mouse signals generated by a workstation and generates a data packet which is transmitted to a central crosspoint switch. The packet is routed through a crosspoint switch to another signal conditioning unit located at a remotely located computer. The second signal conditioning unit applies the keyboard and mouse commands to the keyboard and mouse connectors of the computer as if the keyboard and mouse were directly coupled to the remote computer. Video signals produced by the remote computer are transmitted through the crosspoint switch to the workstation. Horizontal and vertical sync signals are encoded on to the video signals to reduce the number of cables that extend between the workstation and the remote computer. The signal conditioning units connected to the workstations include an onscreen programming circuit that produces menus for the user on a video display of the workstation.

Claims

1. A switching system comprising:

computer-side connectors including plural computer-side user input device connectors and plural computer-side video connectors for simultaneously physically connecting to independent, dedicated cables of respective user-input device inputs and analog video outputs of plural computers;

a first set of user-side connectors including a first user-side user-input device connector and a first user-side video connector for physically connecting to independent, dedicated cables of a first user-input device and an analog video input of a first monitor;

a first analog video receiving circuit interposed between the computer-side connectors and the first set of user-side connectors for receiving analog video signals from one of the plural computers through at least one of the computer-side connectors, and

a first analog video processing circuit, interposed between the computer-side connectors and the first set of user-side connectors, for selecting, for at least one sub-region of an image to be displayed on the first monitor, at least one of (1) a portion of the analog video signals received by the first analog video receiving circuit and (2) internally generated analog video signals, to form an output analog video signal that is output to the first monitor via the first user-side video connector.

2. The switching system as claimed in claim 1, wherein the first analog video receiving circuit further comprises a synchronization signal detecting circuit for detecting one of a horizontal-and a vertical-synchronization signal corresponding to the analog video signals from the at least one of the plural computers through the at least one of the computer-side connectors.

3. The switching system as claimed in claim 1, wherein the first user-input device comprises a computer mouse.

4. The switching system as claimed in claim 1, wherein the first user-input device comprises a keyboard.

5. The switching system as claimed in claim 1, wherein the first analog video processing circuit comprises a multiplexer for multiplexing (1) the portion of the analog video signals received by the first analog video receiving circuit and (2) internally generated analog video signals without requiring a frame buffer.

6. The switching system as claimed in claim 1, further comprising a user-input device translator, disposed between at least one of the plural computer-side user-input device connectors and the first user-side user-input device connector, for translating information from the first user-input device in a first format to a second format used by at least one of the plural computers.

7. The switching system as claimed in claim 1, wherein the first analog video receiving circuit receives separate analog red, green and blue signals.

8. The switching system as claimed in claim 2, wherein the first analog video receiving circuit comprises a receiving circuit for receiving real-time, analog video signals.

9. The switching system as claimed in claim 2, wherein the first analog video receiving circuit comprises a receiving circuit for receiving real-time, analog video signals including the at least one of the horizontal- and a vertical-synchronization signal superimposed on the real-time, analog video signals.

10. The switching system as claimed in claim 8, wherein the first analog video receiving circuit receives separate analog red, green and blue signals.

11. The switching system as claimed in claim 9, wherein the first analog video receiving circuit receives separate analog red, green and blue signals.

12. The switching system as claimed in claim 1, further comprising:

digital switching circuits; and

analog switching circuits, wherein user-input device information is routed from at least one of the plural computer-side user-input device connectors to the first user-side user-input device connector on the digital switching circuits independent of the analog video signals that are routed from at least one of the computer-side video connectors to the first user-side video connector on the analog switching circuits.

13. The switching system as claimed in claim 1, further comprising computer-side audio connectors for receiving audio signals from audio ports of the plural computers, and

wherein the first set of user-side connectors further comprises a user-side audio connector for receiving the audio signals from one of the computer-side audio connectors.

14. The switching system as claimed in claim 1, further comprising:

a second set of user-side connectors including a second user-side user-input device connector and a second user-side video connector for physically connecting to independent, dedicated cables of a second user-input device and an analog video input of a second monitor,

a second analog video receiving circuit for receiving analog video signals from one of the plural computers through the computer-side connectors, and

a second analog video processing circuit for selecting, for at least one sub-region of an image to be displayed on the second monitor, at least one of (1) a portion of the analog video signals received by the second analog video receiving circuit and (2) internally generated analog video signals, to form an output analog video signal that is output to the second monitor via the second user-side video connector.

15. The switching system as claimed in claim 1, further comprising a user-input device command detector, connected to the first user-side user-input device connector, for detecting when configured to detect a first command by which the first user-input device requests that the analog video signals of one of the plural computers be replaced by analog video signals of another of the plural computers and configured to send commands other than the first command from the first user-input device to one of the plural computers.

16. The switching system as claimed in claim 1, further comprising a user-input device command detector, connected to the first user-side user-input device connector, for detecting when configured to detect a first command by which the first user-input device requests that the analog video signals of one of the plural computers be replaced by analog video signals of another of the plural computers in response to the internally generated video signal that is output to the first monitor via the first user-side video connector, and said user-input device command detector configured to send commands other than the first command from the first user-input device to one of the plural computers.

17. The switching system as claimed in claim 1, wherein a first computer-side user-input device connector and a first computer-side video connector of the plural computer-side connectors are contained within a first computer-side housing, and a second computer-side user-input device connector and a second computer-side video connector of the plural computer-side connectors are contained within a second computer-side housing.

18. The switching system as claimed in claim 17, wherein the first and second computer-side housings comprise first and second pod means, respectively.

19. The switching system as claimed in claim 1, wherein the first analog video receiving circuit comprises analog video receiving means for receiving analog video signals from one of the plural computers through the computer-side connectors.

20. The switching system as claimed in claim 1, wherein the first analog video receiving circuit comprises at least one differential line amplifier.

21. The switching system as claimed in claim 1, wherein said at least one of (1) the portion of the analog video signals received by the first analog video receiving circuit and (2) the internally generated analog video signals comprises only (1) the portion of the analog video signals received by the first analog video receiving circuit in a first mode of operation.

22. The switching system as claimed in claim 1, wherein said at least one of (1) a portion of the analog video signals received by the first analog video receiving circuit and (2) internally generated analog video signals comprises only (2) the internally generated analog video signals in a second mode of operation.

23. The switching system as claimed in claim 1, wherein said at least one of (1) the portion of the analog video signals received by the first analog video receiving circuit and (2) the internally generated analog video signals comprises both (1) the portion of the analog video signals received by the first analog video receiving circuit and (2) the internally generated analog video signals in a third mode of operation.

24. The switching system as claimed in claim 1, wherein the first analog video processing circuit comprises analog video processing means for selecting, for the at least one sub-region of an image to be displayed on the first monitor, at least one of (1) the portion of the analog video signals received by the first analog video receiving circuit and (2) internally generated analog video signals, to form an output analog signal that is output to the second monitor via the second user-side video connector.

25. The switching system as claimed in claim 1, wherein the internally generated analog video signals further comprise at least one of an internally generated horizontal synchronization signal and an internally generated vertical synchronization signal.

26. The switching system as claimed in claim 1, wherein the internally generated analog video signals comprise a menu.

27. A system for connecting a workstation of the type that includes a user-input device and a video monitor to plural remote computer systems, comprising:

a first signal conditioning device coupled to the workstation user-input device for receiving a first set of electronic signals produced by the user-input device;

a first communication link coupled to the first signal conditioning device for carrying information corresponding to the received first set of electronic signals;

a crosspoint switch including a number of outputs, said crosspoint switch transferring information corresponding to the received first set of electronic signals from the first communication link to at least one of the outputs;

a plurality of second communication links coupled to the outputs of the crosspoint switch;

a plurality of second signal conditioning devices coupled to the remote computer systems, at least one of the second signal conditioning devices for receiving information corresponding to the received first set of electronic signals transmitted on one of the plurality of second communication links and for supplying the information corresponding to the received first set of electronic signals to a user-input device input of a corresponding remote computer, the plurality of second signal conditioning devices receiving analog video signals produced by the remote computer systems and transmitting the analog video signals to the crosspoint switch; and

an analog video link for coupling the crosspoint switch to a computer monitor associated with the user-input device, wherein the first signal conditioning device further receives a second set of electronic signals, produced by the user-input device, via the first communication link for controlling the crosspoint switch to select the analog video signals of one of the remote computer systems for display on the computer monitor.

28. The system of claim 27, wherein the user-input device comprises a mouse.

29. The system of claim 27, wherein the user-input device comprises a keyboard and the workstation system further comprises a mouse, and wherein the first set of electronic signals includes both keyboard data and mouse data.

30. The system of claim 27, wherein the analog video signals produced by the remote computer systems include red, green and blue video signals.

31. The system of claim 30, wherein the analog video signals further include horizontal and vertical synchronization signals.

32. The system of claim 31, wherein each of the second signal conditioning devices further comprises an encoder circuit that encodes the horizontal and vertical synchronizations signal onto at least one of the red, green and blue video signals before the red, green and blue video signals are transmitted to the crosspoint switch.

33. The system of claim 32, wherein the analog video signals produced by the remote computer systems further include a mode signal that indicates a polarity of the horizontal and vertical synchronization signals, and wherein the encoder circuit encodes the mode signal onto at least one of the red, green and blue video signals before the red, green and blue video signals are transmitted to the crosspoint switch.

34. The system of claim 31, wherein the first signal conditioning device includes a decoder circuit for removing the horizontal and vertical synchronization signals from the at least one of the red, green and blue video signals.

35. The system of claim 33, wherein the first signal conditioning device includes a decoder circuit for removing the mode signal from the at least one of the red, green and blue video signals.

36. The system of claim 35, wherein the decoder circuit includes a circuit for adjusting a polarity for the horizontal and vertical synchronization signals based on the decoded mode signal.

37. The system of claim 35, wherein the first signal conditioning device further comprises an onscreen programming circuit, the onscreen programming circuit producing video signals that are displayed on at least a portion of the video monitor.

38. The system of claim 27, wherein the user-input device comprises a keyboard.

39. The system of claim 37, wherein the onscreen programming circuit comprises onscreen programming means.

40. The system of claim 37, wherein the onscreen programming circuit produces a menu on the at least a portion of the video monitor.

41. A system for connecting a workstation of the type that includes a user-input device and a video monitor to plural remote computer systems, comprising:

a first signal conditioning device coupled to the workstation user-input device for receiving a first set of electronic signals produced by the user-input device;

a first communication link coupled to the first signal condition device for carrying information corresponding to the received first set of electronic signals;

a crosspoint switch including a number of outputs, said crosspoint switch transferring information corresponding to the received first set of electronic signals from the first communication link to at least one of the outputs;

a plurality of second communication links coupled to the outputs of the crosspoint switch; and

a plurality of second signal conditioning devices coupled to the remote computer systems, at least one of the second signal conditioning devices for receiving information corresponding to the received first set of electronic signals transmitted on one of the plurality of second communication links and for supplying the information corresponding to the received first set of electronic signals to a user-input device input of a corresponding remote computer, the plurality of second signal conditioning devices receiving analog video signals produced by the remote computer systems and transmitting the analog video signals to the crosspoint switch;

wherein the first signal conditioning device further receives a second set of electronic signals, produced by the user-input device, via the first communication link for controlling the crosspoint switch to select one of the remote computer systems to receive information corresponding to a third set of electronic signals from the user-input device.

42. The system of claim 41, wherein the first signal conditioning device further comprises an onscreen programming circuit, the onscreen programming circuit producing video signals that are displayed on at least a portion of the video monitor.