Packet-based switch for controlling target computers

• US 7,136,946 B2
• Filed: 04/08/2003
• Issued: 11/14/2006
• Est. Priority Date: 08/25/1999
• Status: Expired due to Term

• Current Assignee: Vertiv IT Systems, Inc. (Vertiv Holdings Co.)
• Original Assignee: Avocent Redmond Corporation (Emerson Electric Company)
• Inventors: Shirley, Timothy C.
• Primary Examiner(s): YANG, RYAN R
• Application Number:
  US10/408,250
• Publication Number:
  US 20030191878A1
• Time in Patent Office: 1,316 Days
• Field of Search: 710/62, 710/100
• US Class Current: 710/62
• CPC Class Codes: G06F 13/107 Terminal emulation
• CPC Class Codes: G06F 2203/0384 Wireless input, i.e. hardware and software details of wireless interface arrangements for pointing devices
• 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: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G09G 2370/24 Keyboard-Video-Mouse [KVM] switch
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04

Abstract

A method and system for converting the output of a communications port (e.g., a serial port or a USB port) into video signals representing the output of a terminal using a KVM switch. Upon receiving characters from the communications port, the system interprets the characters as terminal emulation commands and internally generates a representation of what a resulting terminal screen would look like. From that internal (digital) representation, the system produces analog outputS representing the terminal screen. The analog outputs are output on the monitor attached to the KVM switch.

Claims

1. A switch to selectively communicate keyboard, video and mouse signals between a plurality of target computers and a controlling user interface, comprising:

a target controller housing having thereon a plurality of target computer ports for coupling keyboard, mouse and video signals to and/or from associated target computers via associated target computer interfaces, the target controller housing also separately having a network port for communication with a network;

a target controller within the target controller housing to translate keyboard, video and mouse signals between at least one of the target computer ports and the network port; and

a target controller communication device for communicating the keyboard, video and mouse signals using a packet-based communication protocol on the network port wherein the controlling user interface operates to control a pre-selected target computer via a communication path including, in sequence, the network port utilizing the packet-based communication protocol, the target controller, at least one of the target computer ports utilizing a computer peripheral protocol understood by the controlling user interface and different from the packet-based communication protocol; and

the controlling user interface.

2. The switch as claimed in claim 1, wherein the circuit target controller comprises plural bitmaps representing line-by-line representations of characters stored in the digital memory.

3. The switch as claimed in claim 1, wherein the analyzer and the circuit are target controller is implemented in a field-programmable gate array.

4. The switch as claimed in claim 3, further comprising a configuration memory, wherein the field-programmable gate array is dynamically loaded with a configuration, from the configuration memory, corresponding to a type of terminal to be emulated.

5. The switch as claimed in claim 1, wherein the terminal commands are network port receives commands for a text-based terminal.

6. The switch as claimed in claim 1, wherein the terminal commands are network port receives commands for a graphics-based terminal.

7. The switch as claimed in claim 1, wherein the communications network port comprises a wired communications port.

8. The switch as claimed in claim 1, wherein the communications network port comprises an Ethernet port.

9. The switch as claimed in claim 1, wherein the communications network port comprises an RS-232 port is coupled to a telephone connection.

10. The switch as claimed in claim 1, wherein the communications network port comprises a Token ring port.

11. The switch as claimed in claim 1, wherein the communications network port comprises an ATM port.

12. The switch as claimed in claim 1, wherein the communications network port comprises a wireless communications port.

13. The switch as claimed in claim 1, wherein the communications network port comprises an RF communications port.

14. The switch as claimed in claim 1, wherein the communications network port comprises an IR communications port.

15. The switch as claimed in claim 1, wherein the communications port comprises a packet-based communications port.

16. The switch according to claim 1, wherein the packet-based communication protocol comprises an indirect communication protocol.

17. The switch according to claim 1, wherein the at least one of the target computer ports utilizes a computer peripheral protocol for a video monitor.

18. The switch according to claim 1, wherein the at least one of the target computer ports utilizes a computer peripheral protocol for a user-input device.

19. The switch as claimed in claim 1, wherein the target controller is implemented utilizing a microprocessor.

20. The switch as claimed in claim 1, further comprising a memory for storing an image to be output to the controlling user interface.

21. The switch as claimed in claim 1, wherein commands from the controlling user interface establish the communication path.