GB2185837A

GB2185837A - Remote user interface

Info

Publication number: GB2185837A
Application number: GB08602186A
Authority: GB
Inventors: Christopher Harding Moller
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-01-29
Filing date: 1986-01-29
Publication date: 1987-07-29
Also published as: GB8602186D0

Abstract

A video interface which, while maintaining electrical, mechanical and software capability with existing video interfaces, additionally reports any changes in the data represented on the local screen 3 to a communications port 5. Local video data changes are monitored by circuitry 10 and reported to a communications processor 7. <IMAGE>

Description

SPECIFICATION Remote user interface This invention relates to a remote user interface for a small computer.

Small computers customarily have included within them the necessary electronics to drive a Cathode Ray Tube monitor directly (a 'video interface'). In order for computer programs to send characters or other information to the screen, they must make detailed assumptions about the nature of the video interface. These assumptions are typically deeply embedded within the program, making it very difficult for a user to change the interface to one with a different specification.

One of the reasons why a user might wish to change the method by which the program wrote its data to the screen is that he may wish the monitor and keyboard to be at a greater distance from the computer than a typical video interface is capable of sending its data.

According to the present invention, there is a conventional video interface, with standard software and monitor interfaces, which is in addition provided with a microprocessor dedicated to the function of observing the information which is sent to the conventional screen, and reporting any changes which occur to a special communications port.

Additionally, the interface may have the capability of causing data received from the communications port to simulate key presses on the local keyboard. The special communications port may also be able to function as a conventional communications port, thus eliminating the need to provide that separately.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing.

Fig. 1 shows the block diagram of the unit.

Referring to the drawing, the video interface is driven conventionally from the bus of the computer 1, by commands that depend on the software being used. The conventional interface consists of an amount of read/write memory 2 containing the information currently being displayed, connected via interface logic to the local video monitor 3, under control of the controller circuit 4. A conventional communications port 5 is connected to the bus in the normal manner, but via a multiplexer 6 which allows it alternatively to be driven by the local communications processor 7 via the local bus 8. The local bus also has connected to it memory 9 for the exclusive use of the local processor, for storing the communications program, buffered data and temporary variables. Circuitry 10 is provided to monitor activity in the local video interface, and report data changes to the local processor 7.

1. A video interface which both provides a completely conventional local video display capability, and in addition reports changes that occur on that display to a communications port.

2. A video interface as described in Claim 1, constructed so as to be mechanically and electrically and software compatible with an existing (non-communicating) video interface card.

3. A video interface as described in Claim 1 or 2, in which the communications port adheres to the EIA RS-232C/CCITT V.24 protocol.

4. A video interface as described in Claims 1-3, in which the communicating program is down-loadable from the main computer.

5. A video interface as described in Claims 1-3, in which the communicating program is permanently stored in the interface card.

6. a video interface card as described in any preceding claim, in which a mapping occurs between the features of the local video monitor and the features of remote terminal.

7. A video interface substantially as described herein with reference to Fig. 1 of the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Remote user interface This invention relates to a remote user interface for a small computer. Small computers customarily have included within them the necessary electronics to drive a Cathode Ray Tube monitor directly (a 'video interface'). In order for computer programs to send characters or other information to the screen, they must make detailed assumptions about the nature of the video interface. These assumptions are typically deeply embedded within the program, making it very difficult for a user to change the interface to one with a different specification. One of the reasons why a user might wish to change the method by which the program wrote its data to the screen is that he may wish the monitor and keyboard to be at a greater distance from the computer than a typical video interface is capable of sending its data. According to the present invention, there is a conventional video interface, with standard software and monitor interfaces, which is in addition provided with a microprocessor dedicated to the function of observing the information which is sent to the conventional screen, and reporting any changes which occur to a special communications port. Additionally, the interface may have the capability of causing data received from the communications port to simulate key presses on the local keyboard. The special communications port may also be able to function as a conventional communications port, thus eliminating the need to provide that separately. A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing. Fig. 1 shows the block diagram of the unit. Referring to the drawing, the video interface is driven conventionally from the bus of the computer 1, by commands that depend on the software being used. The conventional interface consists of an amount of read/write memory 2 containing the information currently being displayed, connected via interface logic to the local video monitor 3, under control of the controller circuit 4. A conventional communications port 5 is connected to the bus in the normal manner, but via a multiplexer 6 which allows it alternatively to be driven by the local communications processor 7 via the local bus 8. The local bus also has connected to it memory 9 for the exclusive use of the local processor, for storing the communications program, buffered data and temporary variables. Circuitry 10 is provided to monitor activity in the local video interface, and report data changes to the local processor 7.