Abstract: Apparatus, systems and methods for generating a hybrid on screen display are described. A background image portion of a user interface is generated at a switching device. Video data representing the background image portion of the user interface is transmitted to a user station of a user console. The video data is modified at the user station as it is received using video data representing a user interface element that is specific to the user station. A customized user interface is displayed on a display device attached to the user station.

Abstract: Apparatus and methods for transmitting digital video data and auxiliary data over a four twisted wire pair cable, and systems using such apparatus, are described. A first, second and third digital video color signal and a digital video timing signal are transmitted using differential mode signalling over a first, second, third and fourth twisted wire pair of a cable. Auxiliary data is sent over a data channel using common mode signalling over a first pair of the four twisted wire pairs of the cable. A common mode choke can be used to add or remove a signal sent using the common mode signalling from a pair of wires also used to transmit one of the digital video color or digital video timing signals.

Abstract: Apparatus, systems and methods for generating a hybrid on screen display are described. A background image portion of a user interface is generated at a switching device. Video data representing the background image portion of the user interface is transmitted to a user station of a user console. The video data is modified at the user station as it is received using video data representing a user interface element that is specific to the user station. A customised user interface is displayed on a display device attached to the user station.

Abstract: Apparatus and methods for transmitting digital video data and auxiliary data over a four twisted wire pair cable, and systems using such apparatus, are described. A first, second and third digital video colour signal and a digital video timing signal are transmitted using differential mode signalling over a first, second, third and fourth twisted wire pair of a cable. Auxiliary data is sent over a data channel using common mode signalling over a first pair of the four twisted wire pairs of the cable. A common mode choke can be used to add or remove a signal sent using the common mode signalling from a pair of wires also used to transmit one of the digital video colour or digital video timing signals.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.

Abstract: A video switch for allowing at least two users to view video data from respective ones of at least two video sources. The video switch comprises a switch for selecting one of the at least two video sources and at least one sampler connected to the switch. The sampler is for sampling video data from the at least two video sources. The video switch further comprises a controller for controlling the switch and sampler to select one of the at least two video sources and sample a frame of video data. An output is provided for transmitting video data to one of the at least two users. The output supports a maximum number of simultaneous users which is at least two, and the number of samplers in the video switch is less than the maximum number of simultaneous users. A video switch according to the present invention allows a sampler for capturing video data to be shared between at least two simultaneous users. This reduces the cost, size and complexity of the hardware required to implement a video switch.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.

Abstract: A system, apparatus and methods for transmitting video and audio data over twisted pairs are described. A differential signal that contains video color information is transmitted over each twisted pair. Data representing digital samples of at least one audio signal is transmitted on two or more of the twisted pairs as a common mode signal.

Abstract: A video switch for allowing at least two users to view video data from respective ones of at least two video sources. The video switch comprises a switch for selecting one of the at least two video sources and at least one sampler connected to the switch. The sampler is for sampling video data from the at least two video sources. The video switch further comprises a controller for controlling the switch and sampler to select one of the at least two video sources and sample a frame of video data. An output is provided for transmitting video data to one of the at least two users. The output supports a maximum number of simultaneous users which is at least two, and the number of samplers in the video switch is less than the maximum number of simultaneous users. A video switch according to the present invention allows a sampler for capturing video data to be shared between at least two simultaneous users. This reduces the cost, size and complexity of the hardware required to implement a video switch.

Abstract: Devices for reducing and determining the skew between colour video signals transmitted over at least two different video cables are described. A KVM extender including such devices is also described. The skew reduction device includes a plurality of video signal transmission tracks selectably connectable to each of the video cables to increase the video signal transmission path length so as to more closely matching the total video signal path length for each of the colour video signals. The skew determination device comprises a processing device, a signal generator for applying measuring signals to each of the video signal cables and signal detection circuitry to receive measuring signals transmitted over the video signal cables. Detection signals are output to the processing device which is programmed to determine an indication of the transmission path length difference between the video signal cables.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.

Abstract: A device for interfacing an input device and a computer includes a microprocessor in communication with a memory, the memory storing download instructions and having a re-writable memory area for storing input device driver data downloadable by the microprocessor using the download instructions. The microprocessor is programmed to use the input device driver data to enable data transmission between the computer and the input device. In an alternative device, the microprocessor is programmed to extract input device driver data from data transmitted to the device in a standard input device protocol and to save the input device driver data in the memory. An upgradeable KVMA and KVM switch and extender including such devices are described.

Abstract: Devices for reducing and determining the skew between colour video signals transmitted over at least two different video cables are described. A KVM extender including such devices is also described. The skew reduction device includes a plurality of video signal transmission tracks selectably connectable to each of the video cables to increase the video signal transmission path length so as to more closely matching the total video signal path length for each of the colour video signals. The skew determination device comprises a processing device, a signal generator for applying measuring signals to each of the video signal cables and signal detection circuitry to receive measuring signals transmitted over the video signal cables. Detection signals are output to the processing device which is programmed to determine an indication of the transmission path length difference between the video signal cables.

Abstract: A device for interfacing an input device and a computer includes a microprocessor in communication with a memory, the memory storing download instructions and having a re-writable memory area for storing input device driver data downloadable by the microprocessor using the download instructions. The microprocessor is programmed to use the input device driver data to enable data transmission between the computer and the input device. In an alternative device, the microprocessor is programmed to extract input device driver data from data transmitted to the device in a standard input device protocol and to save the input device driver data in the memory. An upgradeable KVMA and KVM switch and extender including such devices are described.

Abstract: A system for transmitting electrical signals between a computer and peripherals along a twisted pair cable. The system includes a computer interface, a peripheral interface and a twisted pair cable in communication between the computer interface and the peripheral interface. Video and audio signals from the computer are transmitted via the twisted pair cable to the peripherals. Peripheral signals can also be communicated between the computer and peripherals via the twisted pair cable.

Abstract: A serial data routing device for use in routing serial data between a computer and a peripheral device. The data routing device includes a computer data converter which communicates data under the USB protocol with a computer and which converts data received from the computer into converted computer data. A peripheral data converter is also included which communicates data under the USB protocol with the peripheral device and which converts data received from the peripheral device into converted peripheral data. A data router is provided in communication with the computer data converter and the peripheral data converter and transfers converted computer data and converted peripheral data between them. It includes a data routing controller which controls the routing of the converted computer data and the converted peripheral data between the computer data converter and the peripheral data converter such that the computer and peripheral device operate as though directly connected by a USB bus.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.