GB2311491A

GB2311491A - Computer input apparatus

Info

Publication number: GB2311491A
Application number: GB9606357A
Authority: GB
Inventors: Gordon Peter Pratt
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-03-26
Filing date: 1996-03-26
Publication date: 1997-10-01
Also published as: GB9606357D0

Description

COMPUTER INPUT APPARATUS The present invention relates to computer input apparatus and in particular, though not necessarily, to input apparatus for enabling a player to control the playing of a game running on a computer.

The most common apparatus for enabling a user to input data or instructions into a computer is the alphanumeric keyboard and in particular the 'QWERTY' style keyboard.

However, the alphanumeric keyboard is often not best suited for playing computer games or controlling other programs where it is necessary to control a number of parameters relatively rapidly and repeatably. For example, in the case of flight simulators, in addition to controlling the attitude of a plane, it may be necessary to operate 'fire' and missile release controls in an unpredictable manner whilst viewing the action on the screen and it is generally difficult to quickly locate the correct key on a keyboard.

In an attempt to overcome the problems of alphanumeric keyboards, additional input devices such as joysticks and computer mice are often use. These are connected to a different computer input port from the port to which the keyboard is connected and are assigned specific functions by software running on the computer. It is generally not possible for a user to reassign the functions of the additional input devices or to use more than one or two additional input devices. This is due to the limitations of the software and the limited number of computer input ports available. Where use of the software requires control of more than two or three different parameters, even where joysticks, mice etc are available, it is generally necessary to assign the excess control functions to respective keys on a keyboard.

It is an object of the present invention to overcome, or at least mitigate, the above disadvantages of known computer input apparatus.

According to a first aspect of the present invention there is provided computer input apparatus in combination with a computer having a keyboard coupled thereto, the input apparatus and the keyboard being coupled to the computer via a common computer input port and the input apparatus comprising a plurality of user accessible terminals suitable for connection to user actuatable switches, wherein said terminals are mapped to a corresponding plurality of keys on the keyboard and are arranged so that actuation of a said switch is interpreted by the computer as an actuation of the associated key.

The present invention provides an interface between one or more supplementary switches, each of which is assigned to a corresponding key of the keyboard, and the computer. A computer user is therefore able to assign supplementary switches to duplicate the function of selected keys.

The term 'keyboard' is used here in a general sense to mean any device or apparatus which has user operable keys.

This definition therefore includes alphanumeric keyboards, e.g. 'QWERTY' style keyboards, computer mice, or dedicated input devices such as are used with specialised games machines (SEGATM, NINTENDOTM etc).

Preferably, the terminals of the input apparatus to which switches may be connected are in the form of plugs or sockets so as to enable the rapid connection/disconnection of switches by the user.

Preferably, the terminals are set out on the input apparatus in a pattern which corresponds substantially to the pattern of the associated keys on the keyboard. This allows for rapid association of the terminals with the keys by the user. The terminals may be identified by legends which correspond to the markings on the associated keys, e.g. the appropriate alphanumeric characters.

Preferably, a connection terminal is provided for each key on the keyboard. This ensures maximum flexibility for the user. However, in some embodiments of the invention it may only be necessary to provide a connection terminal for each of a subset of keys on the keyboard.

Said switches for use with the input apparatus may be in the form of keys or trigger switches or could be foot operated switches. Other possible switches include voice and light activated switches.

There are a number of possible ways in which the computer input device may be coupled to the computer. One possibility is to provide a 'Y' junction or cable splitter to enable the keyboard and the input device to be coupled in parallel to the input port of the computer. This arrangement has the advantage that both the computer and the keyboard may be of conventional design. The computer input apparatus is arranged to operate on the same principle as the keyboard, where the closing of a switch is detected via the associated terminal and an encoder provided within the input apparatus is arranged to generate in response a unique identifying signal in a form suitable for transmission to the computer. For example, the encoder may be an ASCII encoder. In a modification to this arrangement, the 'Y' junction is provided within the keyboard, at the output of the encoder, and the output from the input apparatus is routed through the keyboard.

A disadvantage of the above arrangement is that much of the circuitry contained in the keyboard, including the encoder, is duplicated in the computer input device. This duplication can be substantially eliminated by connecting the input device to the computer via the keyboard. In alphanumeric keyboards, the keys are arranged at the nodes of a two dimensional array of conductors. When a key is depressed, the two associated lines are short-circuited.

By continuously scanning a 'high' voltage along one set of lines whilst scanning the other set of lines to detect this high voltage, any one key press can be detected uniquely.

Using this arrangement, it is possible for example to provide coverage for a 102 keyboard using a 20 x 9 arrangement of conductors. Thus, in one embodiment of the present invention, these conductors, or a subset thereof, are connected from the keyboard to the computer input device where they are arranged in an array corresponding to the array within the keyboard and are connected to the associated terminals. When a switch is connected to one of the terminals, the effect of closing the switch is to short circuit the two associated lines, producing exactly the same signal as would have been produced if the associated key on the keyboard had been pressed. This signal is detected within the keyboard and the associated encoded signal generated for transmission to the computer by the keyboard encoder.

According to a second aspect of the present invention there is provided computer input apparatus for use with a computer having a keyboard, the input apparatus comprising a plurality of user accessible terminals suitable for connection to user actuatable switches, wherein the terminals correspond in number to the number of keys on the keyboard and are mapped on a one-to-one basis with the keys, the input apparatus being arranged in use so that actuation of a said switch is interpreted by the computer as an actuation of the associated key.

The input apparatus may be arranged in use to be coupled to the computer via the keyboard. Alternatively, the apparatus and the keyboard may be coupled to the computer via a 'Y' junction either internal or external to the computer. As a further alternative, the input apparatus may be connected to a dedicated keyboard 'driver' card mounted in an expansion slot of the computer.

For a better understanding of the present invention and in order to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 illustrates a personal computer coupled to an alphanumeric keyboard and a computer input device embodying the present invention; Figure 2 illustrates schematically the electrical connections and circuitry within and between the keyboard and the computer input device of Figure 1; Figure 3 illustrates a modification which can be made to the internal construction of a conventional keyboard to enable the connection of an input device as shown in Figure 2; and Figures 4 and 5 illustrates second and third embodiments respectively of the present invention.

There is shown in Figure 1 a computer, indicated, generally by the reference numeral 1, having an alphanumeric keyboard 2. The keyboard is connected to the main computer housing 3 by a cable 4 and a computer input port 5. The computer is also provided with an additional computer input apparatus or interface board 6 which provides an interface between the computer and additional switching devices, only one of which is shown in Figure 1 and which is indicated by the reference numeral 7. The interface board 6 is coupled to the keyboard by a cable 8 which connects with a port 28 provided in the keyboard housing.

The function of the interface board will now be explained with reference to Figure 2 which shows in schematic form the internal circuit layouts of the keyboard 2 and the interface board 6. Typically, an alphanumeric keyboard comprises two sets of conductors 9, 10 which are arranged topographically at right angles to one another (in practice the layout of the conductors is more complex).

The keys 11 of the keyboard 2 are arranged at respective nodes intersections 12 of the two sets of conductors 9, 10 so that, when a key is depressed, the two associated conductors are short-circuited together.

A first digital counter 13 receives a clock signal CK and counts from 0 to i-l, where i is the number of vertically extending conductors 9 as viewed in Figure 2.

The output of the counter 13 is provided to a demultiplexer 14 which places a 'HIGH' voltage level on each of the vertically extending conductors 9 in turn, in accordance with the number held by the counter. The clock CK signal is also received by a divide-by-i counter 15 which in turn provides its output to a second digital counter 16. This second counter 16 counts from 0 to j-l, where j is the number of horizontally extending conductors 10. The output of the second counter 16 is provided to a multiplexer 17 which scans each of the horizontally extending conductors 10 in turn and couples the voltage on the conductor being looked at at any given time to an output 18.

The clock rate is such that the array of conductors is scanned many times in a single second. When a key 11 is depressed, the associated vertically and horizontally extending conductors are short-circuited together so that, when these conductors are selected simultaneously by the demultiplexer 14 and the multiplexer 17, a HIGH voltage is coupled to the output 18 of the multiplexer 17. Detection of a HIGH signal, by circuitry not shown in Figure 2, causes the counters 13, 16 to be stopped and the values held therein passed to an ASCII encoder 19 which encodes the counter values into ASCII form for transmission to the computer 1.

As is illustrated in Figure 2, the i x j conductors 9, 10 are coupled to the interface board 6 via an interconnector 20. Within the interface board 6, the conductors are arranged in a pattern substantially identical to that provided within the keyboard 2. However, instead of providing keys at the intersections 12 of the conductors 9, 10, associated sockets 21 are provided. The sockets 21 are arranged across the surface of the interface board 6 in exactly the same pattern as the keys 11 are arranged on the keyboard 2. Each of the sockets is arranged to receive a plug 22 which is connected to a switch device 7. When the switch 23 on the switch device 7 is closed, this short circuits the two associated conductors together in exactly the same manner as is achieved by depressing one of the keys 11 on the keyboard 2. It will be appreciated that the output provided by the multiplexer 17 will be exactly the same whether a key on the keyboard is pressed or whether a switch device coupled to the corresponding socket in the interface board is depressed. Exactly the same values are held in the counters 13, 16 when they are stopped and exactly the same value is output from the ASCII encoder 19 to the computer.

It will be appreciated that the embodiment described above is particularly suited to use in playing computer games. For example, where the game assigns various functions to keys 11 on the keyboard 2, it is possible for a user to couple switch devices 7 to the appropriate sockets 21 on the interface board 6 so as to enable the function of selected keys 11 to be performed by those or switch devices. Whilst it is unlikely that a user would want to couple a switch device to every one of the sockets of the interface board 6, by providing a socket for each key of the keyboard, maximum flexibility of the system is achieved.

In certain circumstances, it may be appropriate to provide sockets corresponding to only a subset of the keys on the keyboard in which case it will only be necessary to connect a subset of the conductors from the keyboard to the interface board.

Figure 3 illustrates a modification which may be made to the construction of a conventional keyboard in order to enable the interface board to be coupled to the keyboard.

The conventional keyboard comprises three layers of flexible plastic 24, 25, 26, with a first set of the conductors 9 being printed on the underside of the upper layer 24. The second set of conductors 10 are printed on the upper surface of the lower plastic layer 26.

Separating the upper and lower plastic layers is a separation layer 25 in which is provided a matrix of holes 27. When the keyboard is assembled, the holes 26 in the intermediate layer 25 are arranged at the intersection of the upper and lower sets of conductors and below respective keys of the keyboard such that when a key is depressed the associated upper and lower conductors are brought into contact through the hole in the intermediate layer.

An over-top layer 29 in the form of a flexible connector has conductors 30 printed on the underside thereof and is located above the upper flexible layer 24.

One end of the over-top layer 29 is bent around an edge of upper flexible plastic layer 24 to connect the two sets of conductors 30, 9. The other end of the over-top layer is coupled to the keyboard port 28 shown in Figure 1.

Similarly, an over-bottom layer 31 is arranged beneath the lower flexible layer 26, and conductors 32 printed on the top side of the over-bottom layer are connected to the conductors 10 on the lower layer 26. The conductors 32 are again coupled to the keyboard port 28. In order to prevent interference of the over-top layer 29 with key presses, the over-top layer may have holes provided therein which are aligned with the keys. The conductors 30 would of course be routed around these holes.

In a second embodiment of the invention, the circuitry provided in the keyboard, including the counters, multiplexer, demultiplexes, and ASCII encoder, is duplicated within the interface board such that the interface board is capable of providing on its own an ASCII code indicative of the socket which has been short circuited by an associated switch. The ASCII signal will be identical to the ASCII signal which is generated within the keyboard when the associated key of the keyboard is depressed. The output of the ASCII encoder can either be routed via a cable connecting the interface board to the keyboard or can be coupled directly to the input port of the computer, for example using a 'Y' junction.

It will be apparent that the present invention may be used to supplement any input device which has a number of keys. For example, as shown in Figure 4, it is possible to provide an interface board with sockets mapped to the buttons of a three button mouse. As shown in Figure 5, it is also possible to provide an interface board having sockets mapped to a 'non-standard' keyboard such as is provided with specialised games machines.

It will be appreciated by the skilled person that modifications may be made to the above described embodiments without departing from the scope of the present invention.

Claims

CLAIMS:

1. Computer input apparatus in combination with a computer having a keyboard coupled thereto, the input apparatus and the keyboard being coupled to the computer via a common computer input port and the input apparatus comprising a plurality of user accessible terminals suitable for connection to user actuatable switches, wherein said terminals are mapped to a corresponding plurality of keys on the keyboard and are arranged so that actuation of a said switch is interpreted by the computer as an actuation of the associated key.

2. Apparatus according to claim 1, wherein the terminals of the input apparatus to which switches may be connected are in the form of plugs or sockets so as to enable the rapid connection/disconnection of switches by the user.

3. Apparatus according to claim 1 or 2, wherein the terminals are set out on the input apparatus in a pattern which corresponds substantially to the pattern of the associated keys on the keyboard.

4. Apparatus according to any one of the preceding claims, wherein a connection terminal is provided for each key on the keyboard.

5. Apparatus according to any one of the preceding claims, wherein the keyboard is an alphanumeric keyboard.

6. Apparatus according to any one of the preceding claims, wherein said terminals are sockets arranged to receive plugs attached to the switches.

7. Computer input apparatus for use with a computer having a keyboard, the input apparatus comprising a plurality of user accessible terminals suitable for connection to user actuatable switches, wherein the terminals correspond in number to the number of keys on the keyboard and are mapped on a one-to-one basis with the keys, the input apparatus being arranged in use so that actuation of a said switch is interpreted by the computer as an actuation of the associated key.

8. Computer input apparatus in combination with a computer and a keyboard substantially or hereinbefore described with reference to Figures 1 to 3 of the drawings or those Figures as modified by Figure 4 or 5.