GB2523564A

GB2523564A - Emergency lighting device and method

Info

Publication number: GB2523564A
Application number: GB1403441.7A
Authority: GB
Inventors: David Lippold
Original assignee: WIREFIELD Ltd
Current assignee: WIREFIELD Ltd
Priority date: 2014-02-27
Filing date: 2014-02-27
Publication date: 2015-09-02
Anticipated expiration: 2034-02-27
Also published as: GB2523564B; GB201403441D0

Abstract

A status monitoring unit for monitoring the status output by an emergency power unit 32, e.g. for an emergency light, taps into signals intercepted between the emergency power supply unit 32 and a status light 36 of the emergency power unit 32. A processor 120 is able to interpret the signals to detect a status being indicated by the emergency power unit 32 at the status light 36. The interpreted status is communicated wirelessly to a remote receiver. Another invention relates to requesting a status request from a remote monitoring unit together with a unique ID.

Description

I

EMERGENCY LIGHTING DEVICE AND METHOD

The present invention relates to an emergency lighting device and method.

Conventional large-scale lighting systems such as those deployed in supermarkets, factories, car parks, office blocks and the like are typically required by law to include an emergency lighting system capable of providing minimum lighting and the lighting of exits in the event of a power cut affecting the main lights.

Typically the emergency lighting system relies on batteries. Consequently the system needs to be tested periodically to ensure that both the batteries and the emergency lights themselves are in working order, However, in large buildings the emergency lights are often not easily accessible for direct physical inspection.

Accordingly, it is known to equip emergency lights with a Digital Addressable Lighting Interface (DALI) and connect them to a lighting control network, This network can then be used to remotely interrogate the emergency lights to receive status reports.

However, this approach is expensive, requiring both the integration of the interface and networking facilities in each light and also provision of the network backbone itself The present invention seeks to alleviate this proNem.

In a first aspect, a status monitoring unit is provided in accordance with claim 1, In another aspect, a portable device is provided in accordance with claim 12, In another aspect, method of monitoring a status is provided in accordance with claim 13, In another aspect, method of monitoring a status is provided in accordance with claim 14, Further respective aspects and features of the invention are defined in the appended claims, Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which: -Figure lisa schematic diagram of a networked lighting system known in the art, -Figure 2 is a schematic diagram of an emergency light known in the art.

-Figure 3 is a schematic diagram of an emergency light in accordance with an embodiment of the present invention.

-Figure 4 is a schematic diagram of a status monitoring unit in accordance with an embodiment of the present invention.

-Figure 5 is a schematic diagram of an emergency light and portable device each in accordance with an embodiment of the present invention.

-Figure 6 is a flow diagram of a method of monitoring a status in accordance with an embodiment of the present invention.

-Figure 7 is a flow diagram of a method of monitoring a status in accordance with an embodiment of the present invention.

An emergency lighting status device and method are disclosed. In the following description, a number of specific details are presented in order to provide a thorough understanding of the embodiments of the present invention. It will be apparent, however, to a person skilled in the art that these specific details need not be employed to practice the present invention. Conversely, specific details known to the person skilled in the art are omitted for the purposes of clarity where appropriate.

Referring to Figure 1, in a comparative example system known in the art, emergency lights (0A, 12A, 14A) are connected to respective emergency power supply units (lOB, 2B, 14B) that each comprise a self-test unit (not shown). Typically each emergency power supply unit is a modular unit that can be connected to a user's emergency light of choice via a commonly available or standardised connector. The emergency light may have a dedicated emergency role, or may be a normal light having a normal usage but also equipped with the emergency power supply unit, thereby doubling as an emergency light in the event of a power cut and the like.

The self-test unit typically comprises an internal timer, enabling it to perform self-tests at periodic intervals; for example it may perform lamp tests weekly, battery charge tests monthly and battery duration tests annually. Typically each self-test unit's timer is randomly offset by a small amount to avoid all emergency lights in a building being in a test mode at the same time, which could be unsafe.

The self-test unit is provided with a DALI network connection and consequently each emergency power supply unit can report the outcome of its self-tests to a central control unit 20 via the network link, illustrated in Figure 1 with dashed lines.

However, as noted previously, this is a costly approach, as it requires the provision of the DALI interface and networking link for each emergency light.

Referring now to Figure 2, this shows an emergency light 30 with, for example, a fluorescent lamp 30A selected solely for illustration; any suitable lamp or configuration of lamps may be envisaged, such as an incandescent lamp, or an array of LEDs, In this case, the emergency light uses an emergency power supply unit 32 similar to that described above (illustrated with diagonal hatching), which comprises a self-test unit 34 (illustrated with vertical hatching) that drives a status light 36. The status light may use different colours and/or pulsing to convey different status messages for visual inspection.

As a non-limiting example the status light may be a bi-colour LED, and it may be used to indicate status as follows: Lamp Indication Corresponding Status Solid green All tests pass Solid red Lamp fault Flashing red Battery fault Fast flash green Function test (30 seconds) in progress Slow flash green Duration test (3 hours) in progress ftthle I -Example status hid/cation by self-test unit status light However, this requires that each status light can be visually inspected when in its deployment position, and requires a person to perform the inspection. In addition to being laborious and prone to error, this is frequently impractical, for example when the emergency lights are in a lift shaft or on a high ceiling.

Referring now to Figure 3, in an embodiment of the present invention, an adapted emergency power supply unit 32' comprises a conventional baftery 38, a conventional a self-test unit 34 connecting to that baftery and with an external connection to the emergency light 30 or lamp 30A, and the conventional self-test unit 34 connects to a conventional status light 36. Notably the adapted emergency power supply unit 32' does not comprise a DALI interface (or if for other reasons it does comprise one, it is not essential to the present invention).

However, the adapted emergency power supply unit 32' does comprise a status light connection monitor 100. The status light connection monitor taps the connection(s) between the self-test unit and the status light, for example by having input wires 102, 104 soldered on to the status light's connectors, or on to connectors of the self-test unit, or indeed onto a circuit board track connecting these, or spliced into connecting wires as applicable according to convenience for the particular make of emergency power supply unit / self-test unit that is being adapted. The input wires may be connected in series or parallel with the status light, depending on the nature of the particular self-test unit being adapted.

Referring now to Figure 4, the status light connection monitor 100 comprises the inputs 102, 104 to receive signals tapped from the connection(s) to the status light. These inputs connect to a central processing unit (CPU) 120, which monitors the received signals and detects the indicated status. Hence using the example status indicators in Table 1, the CPU may detect the polarity of a signal (which is used to select between green and red in the bi-colour LED) and optionally detect the presence of a pulse (flashing). Similarly optionally it may detect the rate of a pulse, if this is used to further distinguish different states. The rate of a pulse may be classified with respect to one or more predetermined threshold frequencies, for example as fast or slow. In this way, the CPU of the status light connection monitor can detect the present output of the self-test unit and hence the state of the emergency power supply unit and/or emergency light.

Whilst there is no standardised set of status light indicators for corresponding statuses, manufacturers of such self-test units use similar indications (e.g. green for pass, red for fail) and there are only a limited number of variations of indications to interpret. Consequently, each manufacturer's set or sets of indicators can be programmed into the status light connection monitor in advance (for example, being stored in a ROM or in the flash memory in a processor-readable format), and the appropriate set for a particular self-test unit can be selected when the status light connection monitor is attached to it, for example by setting an appropriate pattern of DIP switches (not shown) on the status light connection monitor, which serves to set the CPU to detect a corresponding indication/status set. Alternatively these settings may be defined wirelessly, as discussed later herein.

The status light connection monitor may then record in memory HO the detected state that is output to the status light by the self-test unit. Typically the memory is a non-volatile memory such as flash memory.

In some makes of self-test unit, most of the time there may be no signal going to the status light 36 at all, and it remains dark. This may be called a null status. The status light connection monitor may therefor only record the status output by the self-test unit when it changes from the null status to any other status, or when any existing status changes (for example if a test in progress' indicator changes to a test passed' or test failed' indicator).

Meanwhile, some makes of self-test unit emit a constant status indication (e.g. constant green in normal circumstances). In this case the status light connection monitor may periodically store the status even if it does not apparently change; for example it may be stored hourly or daily or at any suitable interval between, Of course, if the status does change, then this may be recorded when it occurs. Hence whilst the status light connection monitor checks the status of the status light constantly or frequently (in the order of seconds or minutes), the result is only stored infrequently (in the order of tens or minutes or tens of hours) or in response to change.

Recording the status at relatively low or infrequent sample periods such as in the order of tens of minutes to tens of hours and/or in response to changes in indicated status has the benefit of reducing the number of writes to the flash memory and hence prolongs its lifespan.

In any event, the recorded status can be associated with a timestamp. In an embodiment of the present invention, the timestamp is based upon a real-time clock, to provide a record of when the corresponding test took place. In another embodiment of the present invention, the timestamp is relative, indicating the time between records. Either timestamp can be approximate, for example to the nearest hour.

As noted above, the self-test unit and/or emergency power supply unit does not require a DALI network interface, or any similar interface. Instead, the status light connection monitor comprises a low-power wireless transceiver 140 connected to an antenna 110, such as a BlueTooth ® transceiver or other common data transceiver, for example on the 2,4GHz band or the 868 N41-lz band.

The CPU 120 monitors for a wireless request for data that may include a unique ID corresponding to that of the self-test unit. Typically the unique ID is set at manufacture (for example, being stored in the flash memory).

In response to such a request, the CPU transmits a data signal comprising the unique ID and data indicative of statuses recorded since the last transmission. The CPU may await an acknowledgement of receipt, and retransmit the data if such an acknowledgement is not received.

The waiting period may be randomised within predetermined bounds to reduce message contention problems in a building with multiple emergency light fixtures in range. Once transmission is finished, the CPU may either record a new timestamp that marks the start of recording new status data for subsequent reporting, or may flush the old status data entirely.

The indicative data may for example be a 4-bit pattern indicating which of up tol6 states was detected (the number of bits and states, and the encoding convention, are non-limiting). The CPU may map the statuses of the particular emergency power unit / self-test unit to which it is attached to this common representation of possible statuses, or the CPU may simply indicate which of the particular statuses of the particular emergency power unit / self-test unit were detected, relying on the receiving device to convert these in a common format if necessary.

Consequently, a user can patrol a building comprising an emergency lighting system adapted according to embodiments described herein, whilst carrying a smartphone, laptop or other portable communications device equipped with a corresponding low-power wireless transceiver.

An application running on the device can have a list of the unique IDs of status light connection monitors deployed in the building, and transmits requests for those monitors that have yet to respond in a given session. The application then records the responses from each monitor in turn as identified by the received unique ID.

In this way, a record of the status of the emergency lighting system can be gathered by a user simply patrolling the building whilst running the application on the portable device.

Alternatively or in addition, to accommodate the possibility of an ID being corrupted or omitted from the list of unique IDs held by the application, the application may transmit a pre-set global override ID. The CPU of ally self-test unit that has not transmifted its status data within a predetermined period (for example the last hour or last day) will transmit its ID and status data in response to this override lID. Again this response may be subject to a random delay to reduce contention, Again it may retransmit if it does not receive an acknowledgement that does include its ID. In this way, no emergency light can be accidentally overlooked, It will be appreciated that this global request signal may be used instead of transmitting successive requests for individual lIDs, for example to prolong battery life on the portable device.

Hence, referring now also to Figure 5, In an embodiment of the present invention an adapted light 30' comprises an adapted emergency power unit 3T that in turn comprises a status light connection monitor 100 (illustrated with horizontal hatching). This monitor can then communicate via antenna 110 with a portable device 200, such as a smartphone, tablet or laptop.

Whilst the example of a user patrolling a building has been used, optionally automatic polling signals may be sent from a central control device running such an application. In this case, the central control device may transmit and receive signals directly, or may use an existing wireless network within the building (such as WiFi® hotspots) to extend its range as required, Hence the central control device may communicate with the status light connection monitors in a star topology, or via a mesh network of relaying components, such as WiFi routers and/or status light connection monitors suitably adapted to relay such signals. Alternatively or in addition in these cases, a status light connection monitor may transmit its data without receiving a request (and optionally without building a record in memory), on the basis that the central control device is always monitoring for such transmissions.

As noted above, the type of self-test unit that a status light connection monitor is connected to may vary and may affect the required interpretation of signals to an indicator lamp. As noted above, the type of self-test unit may therefore be indicated using a hardware setting such as a DIP switch, or may be indicated using the above mentioned wireless link.

For example, when a status light connection monitor is powered up for the first time, it may enter a setting mode for a predetermined period of time (for example 1, 5 or 10 minutes) during which it can receive instmctions wirelessly, including either an instruction for which pre-loaded set of light indications to use, or to receive the appropriate set of light indications to use. Alternatively or in addition, this could be sent to the status light connection monitor in conjunction with its unique ID at any time.

The status light connection monitor may receive power in one or more ways.

In one embodiment of the present invention, the status light connection monitor taps the power of the emergency power supply unit, either directly, or via the self-test unit, Clearly, in this case if the emergency power supply unit itself has a complete battery failure, then the status light connection monitor will no longer work. Hence in this arrangement, a failure of a status light connection monitor to respond to its ID when requested to provide status data is itself an indicator of likely emergency power supply unit baftery failure.

In another embodiment of the present invention, the status light connection monitor receives power from the building in a similar manner to a conventional light, on the basis that there will be conventional power available during tests, and that tests will not occur during a real power failure.

In yet another embodiment of the present invention, the status light connection monitor is provided with its own battery or capacitor based power supply, These batteries or capacitors may be charged using power from the emergency power supply unit and/or the building supply.

Hence in a summary embodiment of the present invention, a status monitoring unit 100 for monitoring the status output by an emergency power unit 3T comprises inputs (102, 1 04) operable to receive signals intercepted between the emergency power unit and a status light of the emergency power unit (more specifically, between the self-test unit of the emergency power unit and the status light). The inputs may be adapted to receive wires, or may be wires extending from the monitor for attachment at the interception point(s), or may be soldering posts for soldering onto a printed circuit board, as applicable. The status monitoring unit also comprises a processing means (e.g. Cpu 120) operable to interpret the signals to detect a status being indicated by the emergency power unit, and a wireless communication means (140, 110) operable to transmit data indicative of an interpreted status to a remote receiver.

Hence advantageously a conventional emergency power unit without a DALI network interface can be easily adapted, by connecting the status monitoring unit to the signal line(s) between the emergency power unit and its status light, to become an emergency power unit capable of wirelessly reporting its status or status history in response to a wireless query, making the polling of emergency light test results much simpler and more accurate than a visual inspection, and much cheaper than a DALI based system.

an instance of the summary embodiment, the status monitoring unit comprises memory means ( 30) operable to store interpreted status data. Hence rather than merely transmitting cunent interpreted status data, the status monitoring unit can transmit a status history comprising multiple status records in response to a wireless request.

lii this instance, as described previously each occurrence of stored interpreted status data may be associated with a timestamp. The timestamp can indicate absolute or relative time, at an appropriate level of granularity such as to the hour, Optionally if no status history has accumulated before a request is received, then the status monitoring unit may transmit just the current status and/or a flag indicating the lack of historical data.

In an instance of the summary embodiment, the wireless communication means is operable to receive a transmission request from a remote receiver, such as a portable device carried by a user, or a central device communicating directly or via a pre-existing WiFi® network, and the processing means is operable in response to cause the data indicative of an interpreted status to be transmitted by the wireless communication means to the remote receiver, In this instance, the status monitoring unit may comprise a unique identification, for example a processor serial number, or a code pre-stored in the memory. Consequently the processing means is operable to cause the data indicative of an interpreted status to be transmitted by the wireless communication means together with the unique identification to the remote receiver, so that the remote receiver can identify the source of the data in the case where there are plural status monitoring units in range.

h this instance, the tnmsmission request itself may comprise a unique identification, in which case the processing means of the status monitoring unit only causes a transmission of the data indicative of an interpreted status (e.g. together with its ID) if the unique identification in the transmission request matches the unique identification of the status monitoring unit.

In an instance of the summary embodiment, the status monitoring unit comprises an emergency power unit interpretation selection means operable to select one of a plurality of interpretation schemes that is appropriate to the emergency power unit from which intercepted signals are received. As noted previously this could be physical, for example in the form of a DIP switch whose settings are interpreted to indicate the selection, or it could be ogical, such as a flag, address, pointer or code uploaded to the status monitoring unit indicating the appropriate interpretation scheme, or simply an upload to the status monitoring unit of the single specific interpretation scheme from among a selection of schemes. Schemes may hence be built into a ROM, pre-loaded into the non-volatile memory 130 or uploaded during initialisation or use as described above.

In this instance the interpretation schemes may associate one or more statuses with one or more signal properties selected from the list consisting of i. the polarity of the signal (for example, indicative of light colour); ii. a duty cycle of the signal (indicative of the light flashing); and iii. a frequency of duty cycle of the signal (indicative of the flash rate, which may be categorised according to one or more threshold frequency values as described previously).

In a summary embodiment of the present invention, an emergency power unit is adapted to comprise a status monitoring unit as described herein. Hence the status monitoring unit is connected to the signal transmission link between the emergency power unit and its status light, either in series or in parallel as appropriate. Typically the signal transmission link comprises two connections to the status light, but in principle may contain one, with the other connection to the status light being to a common ground. It will be appreciated that the status monitoring unit only needs to be connected to the link between the emergency power unit and its status light to the extent necessary to obtain the signals indicative of the statuses that it is desired that the status monitoring unit interprets and reports.

In a summary embodiment of the present invention a light comprises an emergency power unit adapted to comprise a status monitoring unit as described herein. As noted previously the light may be a dedicated emergency light, or a light for normal use equipped with an emergency backup facility in the form of the emergency power unit.

lii a summary embodiment of the present invention a lighting installation comprises a plurality of conventional lights and also one or more lights comprising an adapted emergency power unit as described herein. The lighting installation may be incorporated into any large structure where emergency light monitoring could be laborious or expensive, such as for example a car-park, airport, street, warehouse, stadium, factory, leisure centre, shop, mall, museum, theatre, cinema, hospital, office or municipal building.

In a summary embodiment of the present invention, a portable device (such as a smartphone, laptop or tablet computer) comprises wireless communication means operable to transmit a request for status data from a status monitoring unit of the type described herein, and receive data indicative of an interpreted status of an emergency power unit from the status monitoring unit.

Referring now to Figure 6, in an embodiment of the present invention, a method of monitoring the status of an emergency power unit comprises: -in a first step sGlO, receiving signals intercepted between the emergency power unit and a status light of the emergency power unit; -in a second step s620, interpreting the signals to detect a status being indicated by the emergency power unit; and -in a third step s630, transmitting data indicative of an interpreted status to a remote receiver.

Similarly, referring now to Figure 7, in an embodiment of the present invention, a method of monitoring the status of an emergency power unit, for a device such as a portable device 200, comprises: -in a first step s710, transmitting to a status monitoring unit a request for status data, together with a unique ID associated with the status monitoring unit; -in a second step s720, receiving data indicative of an interpreted status of an emergency power unit from the status monitoring unit corresponding to that unique ID; and -in a third step s730, storing the received data in association with that unique ID.

It will be appreciated that the above methods may be carried out on conventional hardware suitably adapted as applicable by software instruction or by the inclusion or substitution of dedicated hardware.

Thus the required adaptation to existing parts of a conventional equivalent device may be implemented in the form of a computer program product comprising processor implementable instructions stored on a tangible non-transitory machine-readable medium such as a floppy disk, optical disk, hard disk, PROM, RAM, flash memory or any combination of these or other storage media, or realised in hardware as an ASIC (application specific integrated circuit) or an FPGA (field programmable gate array) or other configurable circuit suitable to use in adapting the conventional equivalent device. Separately, such a computer program may be transmitted via data signals on a network such as an Ethernet, a wireless network, the Internet, or any combination of these of other networks,

Claims

CLAIMS1. A status monitoring unit for monitoring a status output by an emergency power unit, the status monitoring unit comprising: inputs operable to receive signals intercepted between the emergency power unit and a status light of the emergency power unit; processing means operable to interpret the signals to detect a status being indicated by the emergency power unit; and wireless communication means operable to transmit data indicative of an interpreted status to a remote receiver.
2. A status monitoring unit according to claim 1, comprising memory means operable to store interpreted status data.
3. A status monitoring unit according to claim 2, in which the each instance of stored interpreted status data is associated with a timestamp.
4. A status monitoring unit according to any preceding claim, in which the wireless communication means is operable to receive a transmission request from a remote receiver; and the processing means is operable in response to cause the data indicative of an interpreted status to be transmitted by the wireless communication means to the remote receiver.
5. A status monitoring unit according to claim 4, comprising a unique identification; and in which the processing means is operable to cause the data indicative of an interpreted status to be transmitted by the wireless communication means together with the unique identification to the remote receiver.
6. A status monitoring unit according to claim 5, in which the transmission request comprises a unique identification; and the processing means only causes a transmission of the data indicative of an interpreted status if the unique identification in the transmission request matches the unique identification of the status monitoring unit.
7. A status monitoring unit according to any preceding claim, comprising: -In I-) emergency power unit interpretation selection means operable to select one of a plurality of interpretation schemes that is appropriate to the emergency power unit from which intercepted signals are received.
8. A status monitoring unit according to claim 7, in which the interpretation schemes associate one or more statuses with one or more signal properties selected from the list consisting of: i. the polarity of the signal; ii. a duty cycle of the signal; and iii. a frequency of duty cycle of the signal.
9. An emergency power unit, comprising: status monitoring unit according to any one of the preceding claims.
0. A light, comprising: an emergency power unit according to claim 8 or claim 9.
11. A lighting installation, comprising: a plurality of lights; and one or more lights according to claim 10.
U. A portable device, comprising: wireless communication means operable to: transmit a request for status data from a status monitoring unit according to any one of claims 4 to 6, and receive data indicative of an interpreted status of an emergency power unit from the status monitoring unit.
H. A method of monitoring a status output by an emergency power unit, comprising the steps of: receiving signals intercepted between the emergency power unit and a status light of the emergency power unit; interpreting the signals to detect a status being indicated by the emergency power unit; and transmitting data indicative of an interpreted status to a remote receiver.
14. A method of monitoring a status output by an emergency power unit, comprising the steps of: transmitting to a status monitoring unit a request for status data, together with a unique ID associated with the status monitoring unit; receiving data indicative of an interpreted status of an emergency power unit from the status monitoring unit corresponding to that unique ID; and storing the received data in association with that unique ID.
15. A computer program for implementing the steps of claim 14 or claim 15.Amendments to the claims have been filed as followsCLAIMS1. A status monitoring unit adapted to monitor a status output by an emergency power unit, the status monitoring unit comprising: inputs adapted to receive signals intercepted between the emergency power unit and a status light of the emergency power unit; processing means adapted to interpret the signals to detect a status being indicated by the emergency power unit; and wireless communication means adapted to transmit data indicative of an interpreted status to a remote receiver.2. A status monitoring unit according to claim 1, comprising memory means adapted to store interpreted status data.3. A status monitoring unit according to claim 2, in which the each instance of stored interpreted status data is associated with a timestamp.IS 4. A status monitoring unit according to any preceding claim, in which the wireless communication means is adapted to receive a transmission request from a r remote receiver; and the processing means is adapted to cause the data indicative of an interpreted status to be transmitted in response by the wireless communication means to the remote receiver.5. A status monitoring unit according to claim 4, comprising a unique identification; and in which the processing means is adapted to cause the data indicative of an interpreted status to be transmitted by the wireless communication means together with the unique identification to the remote receiver.6. A status monitoring unit according to claim 5, in which the transmission request comprises a unique identification; and the processing means only causes a transmission of the data indicative of an interpreted status if the unique identification in the transmission request matches the unique identification of the status monitoring unit.7. A status monitoring unit according to any preceding claim, comprising: emergency power unit interpretation selection means adapted to select one of a plurality of interpretation schemes that is appropriate to the emergency power unit from which intercepted signals are received.8. A status monitoring unit according to claim 7, in which the interpretation schemes associate one or more statuses with one or more signal properties selected from the list consisting of: i. the polarity of the signal; ii. a duty cycle of the signal; and iii. a frequency of duty cycle of the signal.9. An emergency power unit, comprising: status monitoring unit according to any one of the preceding claims.0. A light, comprising: an emergency power unit according to claim 8 or claim 9.11. Alighting installation, comprising: a plurality of lights; and one or more lights according to claim 10. rQ!) U. A portable device, comprising: wireless communication means adapted to: transmit a request for status data from a status monitoring unit according to any one of claims 4 to 6, and receive data indicative of an interpreted status of an emergency power unit from the status monitoring unit.H. A method of monitoring a status output by an emergency power unit, comprising the steps of: receiving signals intercepted between the emergency power unit and a status light of the emergency power unit; interpreting the signals to detect a status being indicated by the emergency power unit; and transmitting data indicative of an interpreted status to a remote receiver.14. A computer program for implementing the steps of claim 13.