1. Field of the Invention
The present invention relates to load control systems for controlling electrical loads and more particularly to a method of establishing communication in a radio frequency (RF) lighting control system between two or more RF control devices that may be communicating on different frequencies.
2. Description of the Related Art
Control systems for controlling electrical loads, such as lights, motorized window treatments, and fans, are known. Such control systems often use radio frequency (RF) transmission to provide wireless communication between the control devices of the system. Examples of RF lighting control systems are disclosed in commonly-assigned U.S. Pat. No. 5,905,442, issued on May 18, 1999, entitled METHOD AND APPARATUS FOR CONTROLLING AND DETERMINING THE STATUS OF ELECTRICAL DEVICES FROM REMOTE LOCATIONS, and commonly-assigned U.S. Pat. No. 6,803,728, issued Oct. 12, 2004, entitled SYSTEM FOR CONTROL OF DEVICES. The entire disclosures of both patents are hereby incorporated by reference.
The RF lighting control system of the '442 patent includes wall-mounted load control devices, table-top and wall-mounted master controls, and signal repeaters. The control devices of the RF lighting control system include RF antennas adapted to transmit and receive the RF signals that provide for communication between the control devices of the lighting control system. The control devices all transmit and receive the RF signals on the same frequency. Each of the load control devices includes a user interface and an integral dimmer circuit for controlling the intensity of an attached lighting load. The user interface has a pushbutton actuator for providing on/off control of the attached lighting load and a raise/lower actuator for adjusting the intensity of the attached lighting load. The table-top and wall-mounted master controls have a plurality of buttons and are operable to transmit RF signals to the load control devices to control the intensities of the lighting loads.
To prevent interference with other nearby RF lighting control systems located in close proximity, the RF lighting control system of the '442 patent preferably utilizes a house code (i.e., a house address), which each of the control devices stores in memory. It is particularly important in applications such as high-rise condominiums and apartment buildings that neighboring systems each have their own separate house code to avoid a situation where neighboring systems attempt to operate as a single system rather than as separate systems. Accordingly, during installation of the RF lighting control system, a house code selection procedure is employed to ensure that a proper house code is selected. In order to accomplish this procedure, one repeater of each system is selected as a “main” repeater. The house code selection procedure is initialized by pressing and holding a “main” button on the selected one repeater in one of the RF lighting control systems. The repeater randomly selects one of 256 available house codes and then verifies that no other nearby RF lighting control systems are utilizing that house code. The repeater illuminates a light-emitting diode (LED) to display that a house code has been selected. This procedure is repeated for each neighboring RF lighting control system. The house code is transmitted to each of the control devices in the lighting control system during an addressing procedure described below.
Collisions between transmitted RF communication signals may occur in the RF lighting control system when two or more control devices attempt to transmit at the same time. Accordingly, each of the control devices of the lighting control system is assigned a unique device address (typically one byte in length) for use during normal operation. The device addresses are unique identifiers that are used by the devices of the control system to distinguish the control devices from each other during normal operation. The device addresses allow the control devices to transmit the RF signals according to a communication protocol at predetermined times to avoid collisions. The house code and the device address are typically included in each RF signal transmitted in the lighting control system. Further, the signal repeaters help to ensure error-free communication by repeating the RF communication signals such that every component of the system receives the RF signals intended for that component.
After the house code selection procedure is completed during installation of the lighting control system, an addressing procedure, which provides for assignment of the device addresses to each of the control devices, is executed. In the RF lighting control system described in the '442 patent, the addressing procedure is initiated at a repeater of the lighting control system (e.g., by pressing and holding an “addressing mode” button on the repeater), which places all repeaters of the system into an “addressing mode.” The main repeater is responsible for assigning device addresses to the RF control devices (e.g., master controls, wall-mounted load control devices, etc.) of the control system. The main repeater assigns a device address to an RF control device in response to a request for an address sent by the control device.
To initiate a request for the address, a user moves to one of the wall-mounted or table-top control devices and presses a button on the control device (e.g., an on/off actuator of the wall-mounted load control devices). The control device transmits a signal associated with the actuation of the button. This signal is received and interpreted by the main repeater as a request for an address. In response to the request for address signal, the main repeater assigns and transmits a next available device address to the requesting control device. A visual indicator is then activated to signal to the user that the control device has received a system address from the main repeater. For example, lights connected to a wall-mounted load control device, or an LED located on a master control, may flash. The addressing mode is terminated when a user presses and holds the addressing mode button of the repeater, which causes the repeater to issue an exit address mode command to the control system.
Some prior art RF lighting control systems are operable to communicate on one of a plurality of channels (i.e., frequencies). An example of such a lighting control system is described in the aforementioned U.S. Pat. No. 6,803,728. The signal repeater of such a lighting control system is operable to determine the quality of each of the channels (i.e., determine the ambient noise on each of the channels), and to choose a select one of the channels for the system to communicate on. An unaddressed control device communicates with the signal repeater on a predetermined addressing frequency in order to receive the device address and the selected channel. However, if there is a substantial amount of noise on the predetermined addressing frequency, the control devices may not communicate properly with the repeater and configuration of the control devices may be hindered. Therefore, it is desirable to allow the RF lighting control system to communicate on the selected channel during the configuration procedure.
According to the present invention, a method of establishing communication with a control device operable to be coupled to a source of power and operable to communicate on a plurality of channels comprises the steps of: (1) transmitting a beacon signal repeatedly on a predetermined channel; (2) the control device listening for the beacon signal for a predetermined amount of time on each of the plurality of channels; (3) the control device receiving the beacon signal on the predetermined channel; and (4) the control device communicating on the predetermined channel.
The present invention further provides a method for configuring a radio frequency control device capable of receiving radio frequency messages on a plurality of radio frequency channels from a first device so as to receive messages transmitted by the first device on a designated one of the radio frequency channels. The method comprises the steps of: (1) a beacon message transmitting device transmitting a beacon message on one of the channels; (2) initiating a beacon monitoring mode at the control device; (3) the control device listening for the beacon message by scanning each of the plurality of radio frequency channels for a period of time; (4) the control device receiving the beacon message on one of the channels; (5) the control device locking on to the one of plurality of channels on which the beacon message is received; and (6) the control device halting further listening in response to the steps of receiving and locking on.
In addition, the present invention provides a control system operable to communicate on a designated radio frequency channel from amongst a plurality of radio frequency channels. The system comprises a beacon message transmitting device and a control device. The beacon message transmitting device is operable to transmit a beacon message on one of the plurality of radio frequency channels. The control device is operable to receive a first transmitted signal on any of the plurality of radio frequency channels, and to monitor for the beacon message on each of the plurality of radio frequency channels for a predetermined period of time until the beacon message is received by the control device on one of the plurality of channels. The control device is further operable to lock on to the one of the plurality of channels on which the beacon message is received, and to subsequently halt further monitoring for the beacon message.
Other features and advantages of the present invention will become apparent from the following description of the invention that refers to the accompanying drawings.
The foregoing summary, as well as the following detailed description of the preferred embodiments, is better understood when read in conjunction with the appended drawings. For the purposes of illustrating the invention, there is shown in the drawings an embodiment that is presently preferred, in which like numerals represent similar parts throughout the several views of the drawings, it being understood, however, that the invention is not limited to the specific methods and instrumentalities disclosed.
The lighting control system 100 comprises a wall-mounted dimmer 112 and a remote dimming module 114, which are operable to control the intensities of the lighting loads 104, 106, respectively. The remote dimming module 114 is preferably located in a ceiling area, i.e., near a lighting fixture, or in another remote location that is inaccessible to a typical user of the lighting control system 100. A motorized window treatment (MWT) control module 116 is coupled to the motorized roller shade 108 for controlling the position of the fabric of the roller shade and the amount of daylight entering the room. Preferably, the MWT control module 116 is located inside the roller tube of the motorized roller shade 108, and is thus inaccessible to the user of the system.
A first wall-mounted master control 118 and a second wall-mounted master control 120 each comprise a plurality of buttons that allow a user to control the intensity of the lighting loads 104, 106 and the position of the motorized roller shade 108. In response to an actuation of one of the buttons, the first and second wall-mounted master controls 118, 120 transmit RF signals 110 to the wall-mounted dimmer 112, the remote dimming module 114, and the MWT control module 116 to control the associated loads.
Preferably, the control devices of the lighting control system 100 are operable to transmit and receive the RF signals 110 on a plurality of channels (i.e., frequencies). A repeater 122 is operable to determine a select one of the plurality of channels for all of the control devices to utilize. For example, 60 channels, each 100 kHz wide, are available in the United States. The repeater 122 also receives and re-transmits the RF signals 110 to ensure that all of the control devices of the lighting control system 100 receive the RF signals. Each of the control devices in the RF lighting control system comprises a serial number that is preferably six bytes in length and is programmed in a memory during production. As in the prior art control systems, the serial number is used to uniquely identify each control device during initial addressing procedures.
The lighting control system 100 further comprises a first circuit breaker 124 coupled between the HOT connection 102 and a first power wiring 128, and a second circuit breaker 126 coupled between the HOT connection 102 and a second power wiring 130. The wall-mounted dimmer 112, the first wall-mounted master control 118, the remote dimming module 114, and the MWT control module 116 are coupled to the first power wiring 128. The repeater 122 and the second wall-mounted master control 120 are coupled to the second power wiring 130. The repeater 122 is coupled to the second power wiring 130 via a power supply 132 plugged into a wall-mounted electrical outlet 134. The first and second circuit breakers 124, 126 allow power to be disconnected from the control devices and the electrical loads of the RF lighting control system 100.
The first and second circuit breakers 124, 126 preferably include manual switches that allow the circuit breakers to be reset to the closed position from the open position. The manual switches of the first and second circuit breakers 124, 126 also allow the circuit breakers to be selectively switched to the open position from the closed position. The construction and operation of circuit breakers is well known and, therefore, no further discussion is necessary.
Prior to the start of the addressing procedure 200, the repeater 122 preferably selects an optimum one of the available channels on which to communicate. To find an optimum channel, the repeater 122 selects at random one of the available radio channels, listens to the selected channel, and decides whether the ambient noise on that channel is unacceptably high. If the received signal strength is greater than a noise threshold, the repeater 122 rejects the channel as unusable, and selects a different channel. Eventually, the repeater 122 determines the optimum channel for use during normal operation. The procedure to determine the optimum channel is described in greater detail in the '728 patent.
Referring to
Referring to
The second beacon process 350, which is executed by each of the control devices of the RF lighting control system 100 at power up, begins at step 360. If the control device has a unique device address at step 362, the process simply exits at step 364. However, if the control device is unaddressed at step 362, the control device begins to communicate on the first channel (i.e., to listen for the beacon message on the lowest available channel) and a timer is initialized to a constant TmAx and starts decreasing in value at step 366. If the control device hears the beacon message at step 368, the control device maintains the present channel as the communication channel at step 370 and exits the process at step 364.
Preferably, the control device listens for a predetermined amount of time (i.e., corresponding to the constant TmAx of the timer) on each of the available channels and steps through consecutive higher channels until the control device receives the beacon message. Preferably, the predetermined amount of time is substantially equal to the time required to transmit the beacon message twice plus an additional amount of time. For example, if the time required to transmit the beacon message once is approximately 140 msec and the additional amount of time is 20 msec, the predetermined amount of time that the control device listens on each channel is preferably 300 msec. Specifically, if the control device does not hear the beacon message at step 368, a determination is made as to whether the timer has expired at step 372. If the timer has not expired, the process loops until the timer has expired. At step 374, if the present channel is not equal to the maximum channel, i.e., the highest available channel, the control device begins to communicate on the next higher available channel and the timer is reset at step 376. Then, the control device listens for the beacon message once again at step 368. If the present channel is equal to the maximum channel at step 374, the control device begins to communicate again on the first channel and the timer is reset at step 378. Accordingly, the second beacon process 350 continues to loop until the control device receives the beacon message.
Referring back to
Next, the remote control devices, i.e., the remote dimming module 114 and the MWT control module 116, are assigned device addresses. In order to prevent the inadvertent assignment of addresses to unaddressed devices in a neighboring RF lighting control system, e.g., an RF lighting control system installed within approximately 60 feet of the system 100, the user cycles power to all of the remote devices at step 215. For example, the user switches the first circuit breaker 124 to the open position in order to disconnect the source from the first power wiring 128, and then immediately switches the first circuit breaker back to the closed position to restore power. Accordingly, the power provided to the remote dimming module 114 and the MWT control module 116 is cycled. Upon power-up, these remote devices set the POWER_CYCLED flag in memory to designate that power has recently been applied. Further, the remote devices begin to decrement a “power-cycled” timer. Preferably, the “power-cycled” timer is set to expire after approximately 10 minutes, after which the remote devices clear the POWER_CYCLED flag.
After the power is cycled, the remote device discovery procedure 216, which is shown in
Referring to
Next, the repeater 122 transmits a “request serial number” message to each device that was stored in memory (i.e., each device having a random slot number and a random data byte stored in memory at step 416). Specifically, at step 418, the repeater transmits the message to the “next” device, e.g., the first device in memory when the “request serial number” message is transmitted for the first time. Since the repeater 122 has stored only the number of the ACK transmission slot and the associated random data byte for each device that transmitted an ACK message, the “request serial number” message is transmitted using this information. For example, the repeater 122 may transmit a “request serial number” message to the device that transmitted the ACK message in slot number 34 with the random data byte OxA2 (hexadecimal). The repeater 122 waits to receive a serial number back from the device at step 420. When the repeater 122 receives the serial number, the serial number is stored in memory at step 422. At step 424, the repeater transmits a “set found flag” message to the present control device, i.e., to the control device having the serial number that was received at step 420. Upon receipt of the “set found flag” message, the remote device sets the FOUND flag in memory, such that the device no longer responds to query messages during the remote device discovery procedure 216. At step 426, if all serial numbers have not been collected, the process loops around to request the serial number of the next control device at step 418.
Since collisions might have occurred when the remote devices were transmitting the ACK message (at step 414), the same subset of devices is polled again at step 412. Specifically, if all serial numbers have been collected at step 426, the process loops around to poll the same subset of devices again at step 412. If no ACK messages are received at step 414, the process flows to step 428. If the variable M is less than a constant MmAX at step 428, the variable M is incremented at step 430. To ensure that all of the devices in the first subset have transmitted an ACK message to the query at step 412 without a collision occurring, the constant MmAx is preferably two (2) such that the repeater 122 preferably receives no ACK messages at step 414 in response to transmitting two queries at step 412. If the variable M is not less than the constant MmAx at step 428, then a determination is made at step 432 as to whether there are more devices to poll. If so, the variable M is set to zero at step 434 and the subset of devices (that are polled in step 412) is changed at step 436. For example, if the devices having even serial numbers were previously polled, the subset is changed to those devices having odd serial numbers. If there are no devices left to poll at step 432, the remote device discovery procedure exits at step 438.
Referring back to
The step of cycling power to the remote devices, i.e., step 215, prevents unaddressed devices in a neighboring system from being addressed. The step of cycling power to the remote devices is very important when many RF lighting control systems are being concurrently installed in close proximity, such as in an apartment building or a condominium, and are being configured at the same time. Since two neighboring apartments or condominiums each have their own circuit breakers, the remote devices of each system can be separately power cycled. However, this step is optional since the user may be able to determine that the present lighting control system 100 is not located close to any other unaddressed RF lighting control systems. If the step of cycling power is omitted from the procedure 200, the repeater 122 polls all unaddressed devices at step 412 in the remote device discovery procedure 216 rather than polling only unaddressed devices that have been recently power cycled. Further, the step of cycling power need not occur after step 212, but could occur at any time before the remote device discovery procedure, i.e., step 216, is executed, as long the “power-cycled” timer has not expired.
The remote “out-of-box” procedure 500 begins at step 505 and the lighting control system 100 enters an “out-of-box” mode at step 510, for example, in response to a user pressing and holding an actuator on the repeater 122 for a predetermined amount of time. Next, the repeater 122 begins to transmit a beacon message to the control devices on the selected channel (i.e., the channel that is used during normal operation) at step 512. Specifically, the repeater 122 executes the first beacon process 300 of
Next, the control devices coupled to the first power wiring 128, i.e., the devices that were power cycled, execute a third beacon procedure 600.
Further, the third beacon process 600 is prevented from looping forever as in the second beacon process 350, such that the control device is operable to return to normal operation if the control device does not hear the beacon message. To achieve this control, a variable K is used to count the number of times the control device cycles through each of the available channels listening for the beacon message. Specifically, the variable K is initialized to zero at step 610. At step 624, if the variable K is less than a constant KmAx, the variable K is incremented and the control device begins to communicate on the first channel and the timer is reset at step 630. Accordingly, the control device listens for the beacon message on each of the available channels once again. However, if the variable K is not less than the constant KmAx at step 624, the third beacon process 600 exits at step 632. Preferably, the value of KmAX is two (2), such that the control device listens for the beacon message on each of the available channels twice.
In summary, after power is cycled to the desired control device at step 514, the control devices coupled to the first power wiring 128 execute the third beacon process 600. Thus, these control devices are operable to communicate on the selected channel.
Next, a remote device discovery procedure 516 is executed by the repeater 122. The remote device discovery procedure 516 is very similar to the remote device discovery procedure 216 shown in
At step 518, the repeater 122 compiles a list of serial numbers of all remote devices found in the remote device discovery procedure 516. At step 520, the user may manually choose which of the control devices in the list are to be reset to the default factory settings, for example, by using a GUI software. Accordingly, the user can step through each control device in the list of serial numbers and individually decide which devices to restore to the “out-of-box” setting. Finally, the selected control devices are restored to the “out-of-box” setting at step 522 and the user causes the lighting control system 100 to exit the remote “out-of-box” mode at step 524, e.g., by pressing and holding an actuator on the repeater 122 for a predetermined amount of time.
While the present invention has been described with reference to an RF lighting control system, the procedures of the present invention could be applied to other types of lighting control system, e.g., a wired lighting control system, in order to establish communication with a remotely-located control device on a wired communication link using a desired channel.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will be apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.
This application is a continuation of U.S. patent application Ser. No. 11/470,408, filed Sep. 6, 2006 by Brian Michael Courtney et al., now U.S. Pat. No. 7,880,639, entitled METHOD OF ESTABLISHING COMMUNICATION WITH WIRELESS CONTROL DEVICES the entire contents of which is hereby incorporated by reference.
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Entry |
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Indian Office Action issued in Indian Patent Application No. 1259/CHENP/2009 dated Feb. 6, 2014. |
Number | Date | Country | |
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20110025476 A1 | Feb 2011 | US |
Number | Date | Country | |
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Parent | 11470408 | Sep 2006 | US |
Child | 12876768 | US |