GB2289152A - Control panel - Google Patents

Abstract

A control panel has a keypad comprising a plurality of keys, means for mounting the panel in more than one orientation and means for assigning a function to each key dependent on the orientation of the panel. The function assignment may be controlled by pressing a predetermined pattern of keys, or a predetermined key one or more times (e.g. Fig. 3), or using reversible key plugs. <IMAGE>

Description

CONTROL PANEL The present invention relates to a control panel and in particular, for example, to a control panel for an alarm system.

Typically, a control panel for a control system has a keypad, comprising a plurality of keys, which is usable to input e.g. data and/or instructions into thecontrol system. Usually such a control panel is designed to be mounted (e.g. on a wall or other fixing) in a particular orientation, and the layout of the keys of the keypad is designed to be appropriate for the chosen orientation.

It may be possible to mount such panels in an orientation other than that in which they were designed to be mounted, but the problem then arises that the layout of the keypad will not be appropriate for the non-designed orientation.

The present invention aims to provide a control panel which is mountable in more than one orientation and which mitigates the above problem.

Accordingly, in a first aspect, the present invention provides a control panel having a keypad comprising a plurality of keys, the panel also including means for mounting the panel in more than one orientation and means for assigning a function to each key dependent on the orientation of the panel.

In this way, a panel is provided which for which a user can select from more than one possible mounting orientations and for which the functions of the keys of the keypad are alterable in accordance with the orientation of the panel. Thus the layout of the keypad may effectively be adjusted to adapt it to a particular orientation.

The control panel may also include some or all of the control circuitry for the control system. Alternatively, the panel may be remote from some or all of the control circuitry, and may even comprise substantially only the keypad, and possibly some circuitry associated with the keypad.

The keypad may comprise an array of keys (i.e. a plurality of rows and a plurality of columns) and a particular function may be assigned to a particular key designated by its row and column address. Each key may be capable of being assigned more than one function, which may be dependent upon the orientation of the panel.

The means for assigning a function to each key may include memory means, such as non-volatile memory (NVM), for storing a plurality of key tables, each key table relating to the functions of the keys in one particular orientation.

Alternatively, the means for assigning the function to each key may include connector means, the connector means being connectable in a plurality of ways dependent on the orientation of the panel. Such connector means could be provided, for example, by a reversible plug having two portions which are connectable together in more than one orientation.

When connected together in a first orientation, the plug may connect a particular key to a particular part of the control circuitry, thereby assigning a particular function to that key, and when connected together in a second orientation may provide a different connection, thereby assigning a different function to the key. The connector may function similarly for the other keys of the key pad.

The panel may also include input means by which a user can input information relating to the orientation of the panel, thereby determining the function assigned to each key by the means for assigning. Such input means may include, for example, one or more keys of the keypad, which keys may also perform other functions.

For example, to input the information a user may press a predetermined pattern of keys, or press a predetermined key one or more times, with the orientation of the panel being determinable by the input means from this key operation. The key operation may take place e.g upon 'Xpower-up" of the panel, or at any other suitable time.

The one or more orientations of the panel may include a "horizontal" and a "vertical" orientation. If, for example, the panel is to be mounted on a wall, then the panel may be mounted with its major axis in either a horizontal or a vertical position. In this specification these are referred to as the "horizontal" and the "vertical" orientations respectively. Other orientations and/or ways of mounting the panel may be provided for.

An embodiment of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a control panel according to the present invention in a horizontal position; Figure 2 shows a control panel according to the present invention in a vertical position; Figure 3 is a flow chart of part of the operation of the control panel for determining the orientation of the panel; Figure 4 is a flow chart of part of the normal operation of the control panel; and Figure 5 is a circuit diagram of part of a control circuit relating to the keypad of a control panel according to the present invention.

Figure 1 shows a control panel 2 having a keypad 4 consisting of 12 keys 6 (designating numerals 0-9 and "no" and "yes"). There is also a row of LEDs 8 which may be used to indicate various states of a control system of which the control panel is a part.

In figure 1, the control panel 2 is shown in a "horizontal" position, in which the keypad 4 is arranged in an array of 3 x 4 as follows: KEY TABLE 1 Row 1 Row 2 Row 3 Row 4 (PC3) (PC4) (PC5) (PC6) Column 1 (PC0) 1 2 3 4 Column 2 (PC1) 5 6 7 8 Column 3 (PC2) No 9 0 Yes Figure 2 shows the control panel 2 mounted in a "vertical" position. Mounting means (not shown) may be provided on the rear of the panel to facilitate the mounting of the panel in different orientations. In the vertical position, the keys of the keypad are effectively arranged in an array of 4 x 3.

If the panel 2 was simply turned through 900 and mounted in a vertical position, the layout of the keypad would be as follows: Column 3 Column 2 Column 1 (PC2) (PC1) (PC0) Row 1 (PC3) No 5 1 Row 2 (PC4) 9 6 2 Row 3 (PC5) 0 7 3 Row 4 (PC6) Yes 8 4 However, the panel 2 includes means for assigning a function to each key dependent on the orientation of the panel, and so in the vertical orientation the keys are assigned different functions as follows: KEY TABLE 2 Column 3 Column 2 Column 1 (PC2) (PC1) (PC0) Row 1 (PC3) 1 2 3 Row 2 (PC4) 4 5 6 Row 3 (PC5) 7 8 9 Row 4 (PC6) No 0 Yes Thus the panel may be used in different orientations - in this case horizontal and vertical - whilst still providing a keypad with a layout that is logically arranged and is in a pattern familiar to a user.

Relabelling of the keys in the different orientations may, for example, be achieved by providing a plurality of templates or overlays which fit over the keypad, or by providing a plurality of adhesive labels for the keys.

The functions assigned to the keys may be determined as follows: When the panel is first powered up, a microprocessor 20 (see figure 5) checks memory means (not shown), such as non-volatile memory (NVM), and may see that the memory is not programmed. If this is the case, it may copy a default key table, for example key table 1 relating to the horizontal position, into the memory.

During a predetermined period of time, such as the first eight seconds after application of power to the panel, it may then be possible to alter the configuration of the keypad to conform to the chosen orientation of the panel.

This may be achieved, for example, by operation of a predetermined sequence of keys or repeated operation of a particular key.

In one embodiment, the user twice presses (what to the user is) the "0" key. If this key corresponds to that in row 3, column 3, then the panel "knows" that it is in the horizontal position. Alternatively if the "0" key corresponds to that of column 2, row 4, then the panel "knows" that it is in the vertical position. If it is in the vertical position, the microprocessor then copies key table 2 into the memory, replacing key table 1.

Thereafter, any key pressed will be decoded using the appropriate key table, thus giving the correct value required by the user.

The orientation can be changed at any time by, for example, removing power from the system, reapplying power and repeating the above operation. Means may be provided for downloading the stored key table from the nonvolatile memory so that, should power be lost and then reapplied, the chosen type of keypad orientation is stored as the default listing.

Figure 3 shows a flow chart outlining the above-described procedure for selecting either the horizontal or vertical tables for storage in the memory. Once the appropriate table is stored, normal operation of the keypad follows, a flow chart for which is given in figure 4. Basically, when a key is pressed its function is determined by the key table stored in the memory.

Figure 5 shows a partial circuit diagram for the means for assigning a function to the keys of the keypad dependent on the orientation of the panel. Generally, a microprocessor 20 is used to read the keypad and control the functioning of the keypad.

In this embodiment, the keypad port on the microprocessor 20 is also responsible for driving the indicator LEDs 8.

The two functions are multiplexed together such that for half the time the LEDs are switched on and the data on PC0 through PC6 contains valid LED information. For the remainder of the time the port is used to read the keypad. This can be achieved by using the persistence inherent in an LED and a fast switching frequency such that to the eye the LED(s) appears to be illuminated constantly.

When the processor is scanning the keypad, the port is configured with PC0, PC1 and PC2 (corresponding to the columns of key table 1) set as outputs, and PC3, PC4, PC5 and PC6 (corresponding to the rows of key table 1) as inputs. Typically each of the columns (as drawn in the circuit diagram, PC0, 1 and 2) is driven high in turn, with the other two columns being driven low. Then the inputs are read to see if any are high as this will correspond to a key being pressed, with all rows from unpressed keys returning a low value due to the effects of R21, R22, R23, R24. The function of diodes D5, D6, D7 is to protect the processor from short circuit damage should two keys of the same row be pressed at the same time.

To explain further, consider the following example.

Assume that the key marked T2 has been depressed.

Initially PC0 is set high (at 5 volts), and PC1 and PC2 are low (at 0 volts). The pins PC3, PC4, PC5, PC6 are then read in one operation and will all read as a low (0 volts) because none of T11,12,5,6 have been pressed. At this stage the value of the port will be 00000001, where the left most digit corresponds to PC7 (not used and always low), the next four are PC6, PC5, PC4, PC3 respectively and the next three PC2, PC1, PC0 with PCo at level 1 as this is the output set high.

The next stage is to set PC1 as high and force PC2 and PC0 to a low. Once again the inputs PC3, PC4, PC5, PC6 are read but this time PC4 will be high because T2 is depressed, and the other three inputs will be low. The value of the port is now 00010010.

The fact that there is more than one "1" is indicative of a keypress. To complete the scan PC2 is driven high whilst PC0 and PC1 are held low. In this situation the inputs will all read low and the value of the port is 00000100.

In other words the result of the keys can routine will be 00010010. This indicates that a key is pressed (if no key is pressed the result would be 00000000) and also details exactly which of the rows is shorted to which of the columns.

This value is then validated and debounced by repeatedly reading the same result over a period of time. Once the key has been confirmed then this value (namely 00010010 in this case) is passed to the key table to determine the actual numeric value of the key pressed. Thus if the panel is in horizontal (default) (table 22 of figure 5) mode then the numeric value of T2 is "6", or if in vertical mode (table 24) then the numeric value is "5".

The above description is by way of example only, and modifications will be apparent to those skilled in the art.

Claims (11)

CLAIMS:

1. A control panel having a keypad comprising a plurality of keys, the panel also including means for mounting the panel in more than one orientation and means for assigning a function to each key dependent on the orientation of the panel.

2. A control panel according to claim 1 including means for assigning a particular function to each key and wherein each key is capable of being assigned more than one function dependent upon the orientation of the panel.

3. A control panel according to claim 2 wherein the means for assigning a function to each key includes memory means for storing a plurality of key tables, each key table relating to the functions of the keys in one particular orientation of the panel.

4. A control panel according to claim 2 wherein the means for assigning a function to each key includes connector means, the connector means being connectable in a plurality of ways dependent on the orientation of the panel.

5. A control panel according to any of the above claims including input means by which a user can input information relating to the orientation of the panel.

6. A control panel according to any one of the above claims adapted and arranged for use with an alarm system.

7. A control panel substantially as any one embodiment herein described with reference to the accompanying drawings.

8. An alarm system including a control panel according to any one of the above claims.

9. A method of assigning functions to keys of a control panel of an alarm system depending upon the orientation of the control panel, the method including the steps of: (1) either operating a particular key a predetermined number of times or operating a number of keys in a predetermined sequence; (2) depending upon the results of step (1), assigning a particular function to each key.

10. A method according to claim 9 wherein the step of assigning is performed by transferring a particular key table into a memory of the control panel, said key table containing the values for each key.

11. A method according to claim 9 or claim 10 wherein steps 1 and 2 are performed when power is first applied to the control panel.