Computer interconnection system

• US 8,443,037 B2
• Filed: 09/21/2010
• Issued: 05/14/2013
• 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: Beasley, Danny L., Seifert, Robert V. Jr., Lacrampe, Paul, Greene, Thomas, Hafer, Kevin J., Huffington, James J.
• Primary Examiner(s): Dalencourt, Yves
• Application Number:
  US12/887,368
• Publication Number:
  US 20110010632A1
• Time in Patent Office: 966 Days
• Field of Search: 709/203, 709/208, 709/209, 710/2, 710/38, 710/51, 715/716, 715/733, 715/810, 715/856
• US Class Current: 709/203
• 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 system for connecting a workstation including a keyboard, a cursor control device and a video monitor and a plurality of computers including first and second computers, the system comprising:

a programmable switch for routing keyboard and cursor control signals from the workstation to the first computer and for routing video signals from the first computer to the video monitor of the workstation;

a first interface circuit for receiving keyboard and cursor control device signals from the workstation;

said first interface circuit transmitting the keyboard and cursor control device signals to the programmable switch;

a second interface circuit disposed between the programmable switch and the first computer for supplying the keyboard and cursor control device signals routed through the programmable switch to the first computer;

an on-screen programming circuit, disposed between the first interface circuit and the second interface circuit, that produces video signals for display on the video monitor;

wherein the video signals generated by the on-screen programming circuit cause the video monitor to display a menu of switching system control options;

a programmable logic circuit, disposed between the first interface circuit and the second interface circuit, the programmable logic circuit operating to detect keyboard or cursor control device signals received while the on-screen programming circuit is producing the menu of switching system control options and to control the programmable switch in response to the keyboard or cursor control device signals detected; and

wherein a first set of keyboard signals is received at the first interface circuit from the keyboard, and information corresponding to the first set of keyboard signals is propagated to the first computer through the second interface circuit;

wherein a second set of keyboard signals is received at the first interface circuit from the keyboard, is further received by the programmable logic circuit that prevents the second set of keyboard signals from being propagated to any of the plurality of computers, and causes the on-screen programming circuit to produce the menu of switching system control options for display on the video monitor;

wherein a third set of keyboard signals is received at the first interface circuit from the keyboard, corresponds to a selection of at least one of the switching system control options, and is further received by the programmable logic circuit that prevents the third set of keyboard signals from being propagated to any of the plurality of computers; and

wherein a fourth set of keyboard signals is received at the first interface circuit from the keyboard, and information corresponding to the fourth set of keyboard signals is propagated to the second computer through the programmable switch in response to the selection of at least one of the switching system control options using the keyboard.

2. The system as claimed in claim 1, wherein the second set of keyboard signals comprises more than one keystroke entered on the keyboard.

3. The system as claimed in claim 1, wherein the programmable logic circuit controls the on-screen programming circuit to produce the menu of switching system control options upon the detection of a predefined input from a user of the workstation.

4. The system as claimed in claim 1, wherein the programmable logic circuit determines for each set of keyboard signals whether the keyboard signals are to be propagated to one of the plurality of computers, or whether the keyboard signals correspond to the selection of at least one of the switching system control options.

5. The system as claimed in claim 2, wherein the programmable logic circuit determines for each set of keyboard signals whether the keyboard signals are to be propagated to one of the plurality of computers, or whether the keyboard signals correspond to the selection of at least one of the switching system control options.

6. The system as claimed in claim 3, wherein the programmable logic circuit determines for each set of keyboard signals whether the keyboard signals are to be propagated to one of the plurality of computers, or whether the keyboard signals correspond to the selection of at least one of the switching system control options.

7. The system as claimed in claim 1, wherein the programmable logic circuit comprises a processor.

8. The system as claimed in claim 2, wherein the programmable logic circuit comprises a processor.

9. The system as claimed in claim 3, wherein the programmable logic circuit comprises a processor.

10. The system as claimed in claim 4, wherein the programmable logic circuit comprises a processor.

11. The system as claimed in claim 5, wherein the programmable logic circuit comprises a processor.

12. The system as claimed in claim 6, wherein the programmable logic circuit comprises a processor.

13. The system as claimed in claim 1, wherein the programmable logic circuit comprises a programmed microprocessor.

14. The system as claimed in claim 2, wherein the programmable logic circuit comprises a programmed microprocessor.

15. The system as claimed in claim 3, wherein the programmable logic circuit comprises a programmed microprocessor.

16. The system as claimed in claim 4, wherein the programmable logic circuit comprises a programmed microprocessor.

17. The system as claimed in claim 5, wherein the programmable logic circuit comprises a programmed microprocessor.

18. The system as claimed in claim 6, wherein the programmable logic circuit comprises a programmed microprocessor.

19. The system as claimed in claim 1, wherein information corresponding to the third set of keyboard signals is propagated to the programmable switch.

20. The system as claimed in claim 6, wherein information corresponding to the third set of keyboard signals is propagated to the programmable switch.

21. A system for connecting a workstation including a keyboard, a cursor control device and a video monitor and a plurality of computers including first and second computers, the system comprising:

a programmable switch for routing keyboard and cursor control signals from the workstation to the first computer and for routing video signals from the first computer to the video monitor of the workstation;

a first interface circuit for receiving keyboard and cursor control device signals from the workstation;

said first interface circuit transmitting the keyboard and cursor control device signals to the programmable switch;

a second interface circuit disposed between the programmable switch and the first computer for supplying the keyboard and cursor control device signals routed through the programmable switch to the first computer;

an on-screen programming circuit, disposed between the first interface circuit and the second interface circuit, that produces video signals for display on the video monitor;

wherein the video signals generated by the on-screen programming circuit cause the video monitor to display a menu of switching system control options;

a programmable logic circuit, disposed between the first interface circuit and the second interface circuit, the programmable logic circuit operating to detect keyboard or cursor control device signals received while the on-screen programming circuit is producing the menu of switching system control options and to control the programmable switch in response to the keyboard or cursor control device signals detected; and

wherein a first set of keyboard signals is received at the first interface circuit from the keyboard, and information corresponding to the first set of keyboard signals is propagated to the first computer through the second interface circuit;

wherein a second set of keyboard signals is received at the first interface circuit from the keyboard, is further received by the programmable logic circuit that prevents the second set of keyboard signals from being propagated to of the plurality of computers, and causes the on-screen programming circuit to produce the menu of switching system control options for display on the monitor;

wherein a first set of cursor control device signals is received at the first interface circuit from the cursor control device, corresponds to a selection of at least one of the switching system control options, and is further received by the programmable logic circuit that prevents the first set of cursor control device signals from being propagated to any of the plurality of computers; and

wherein a third set of keyboard signals is received at the first interface circuit from the keyboard, and information corresponding to the third set of keyboard signals is propagated to the second computer through the programmable switch in response to the selection of at least one of the switching system control options using the cursor control device.

22. The system as claimed in claim 21, wherein the second set of keyboard signals comprises more than one keystroke entered on the keyboard.

23. The system as claimed in claim 21, wherein the programmable logic circuit controls the on-screen programming circuit to produce the menu of switching system control options upon the detection of a predefined input from a user of the workstation.

24. The system as claimed in claim 21, wherein the programmable logic circuit determines for each set of cursor control device signals whether the cursor control device signals are to be propagated to one of the plurality of computers, or whether the cursor control device signals correspond to the selection of at least one of the switching system control options.

25. The system as claimed in claim 22, wherein the programmable logic circuit determines for each set of cursor control device signals whether the cursor control device signals are to be propagated to one of the plurality of computers, or whether the cursor control device signals correspond to the selection of at least one of the switching system control options.

26. The system as claimed in claim 23, wherein the programmable logic circuit determines for each set of cursor control device signals whether the cursor control device signals are to be propagated to one of the plurality of computers, or whether the cursor control device signals correspond to the selection of at least one of the switching system control options.

27. The system as claimed in claim 21, wherein the programmable logic circuit comprises a processor.

28. The system as claimed in claim 22, wherein the programmable logic circuit comprises a processor.

29. The system as claimed in claim 23, wherein the programmable logic circuit comprises a processor.

30. The system as claimed in claim 24, wherein the programmable logic circuit comprises a processor.

31. The system as claimed in claim 25, wherein the programmable logic circuit comprises a processor.

32. The system as claimed in claim 26, wherein the programmable logic circuit comprises a processor.

33. The system as claimed in claim 21, wherein the programmable logic circuit comprises a programmed microprocessor.

34. The system as claimed in claim 22, wherein the programmable logic circuit comprises a programmed microprocessor.

35. The system as claimed in claim 23, wherein the programmable logic circuit comprises a programmed microprocessor.

36. The system as claimed in claim 24, wherein the programmable logic circuit comprises a programmed microprocessor.

37. The system as claimed in claim 25, wherein the programmable logic circuit comprises a programmed microprocessor.

38. The system as claimed in claim 26, wherein the programmable logic circuit comprises a programmed microprocessor.

39. The system as claimed in claim 21, wherein information corresponding to the first set of cursor control device signals is propagated to the programmable switch.

40. The system as claimed in claim 26, wherein information corresponding to the first set of cursor control device signals is propagated to the programmable switch.