METHOD OF DISCOVERING A REMOTELY-LOCATED WIRELESS CONTROL DEVICE

Abstract
The present invention provides a method of discovering a remotely-located control device in a wireless control system having a plurality of control devices. Each of the control devices of the control system has a unique serial number. A query message is first transmitted to the plurality of control devices. An acknowledgement message is transmitted from the first control device in response to the query message. The acknowledgement message is transmitted in a random transmission slot and contains a random data byte. The first control device is identified by the random transmission slot and the random data byte. The serial number of the first control device is requested, and transmitted from the first control device. At this time, the control device is operable to be assigned a unique device address.
Description

BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a simplified block diagram of an RF lighting control system according to the present invention;



FIG. 2 is a flowchart of an addressing procedure for the RF lighting control system of FIG. 1 according to the present invention; and



FIG. 3 is a flowchart of a remote device discovery procedure for the RF lighting control system of FIG. 1 according to the present invention.





DETAILED DESCRIPTION OF THE INVENTION

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.



FIG. 1 is a simplified block diagram of an RF lighting control system 100 according to the present invention. The RF lighting control system 100 is operable to control the power delivered from a source of AC power to a plurality of electrical loads, for example, lighting loads 104, 106 and a motorized roller shade 108. The RF lighting control system 100 includes a HOT connection 102 to a source of AC power for powering the control devices and the electrical loads of the lighting control system. The RF lighting control system 100 utilizes an RF communication link for communication of RF signals 110 between control devices of the system.


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. 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 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.



FIG. 2 is a flowchart of an addressing procedure 200 for the lighting control system 100 according to the present invention. The addressing procedure 200 is operable to assign device addresses to remotely-located control devices, such as, for example, the remote dimming module 114 and the MWT control module 116. Since an unaddressed control device does not know which of the available communication channels the repeater 122 has selected for use during normal operation, all of the unaddressed control devices communicate on a predetermined addressing channel that is different than the selected channel. Each of the remote devices includes a number of flags that are utilized during the addressing procedure 200. The first flag is a POWER_CYCLED flag that is set when power has recently been cycled to the remote device. As used herein, “power cycling” is defined as removing power from a control device and then restoring power to the control device to cause the control device to restart or reboot. The second flag is a FOUND flag that is set when the remote device has been “found” by a remote device discovery procedure 216 to be described in greater detail below with reference to FIG. 3.


The addressing procedure 200 begins when the lighting control system 100 enters an addressing mode at step 210, for example, in response to a user pressing and holding an actuator on the repeater 122 for a predetermined amount of time. At step 212, the user manually actuates the non-remote devices, i.e., the wall-mounted dimmer 112 and the first and second wall-mounted master controls 118, 120, as in the addressing procedure of the prior art lighting control system disclosed in the '442 patent. In response to an actuation of a button, the non-remote devices transmit a signal associated with the actuation of the button to the repeater 122 on the predetermined addressing channel. Accordingly, the repeater 122 receives the signal, which is interpreted as a request for an address, and transmits the next available device address to the actuated non-remote control device.


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 214. 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 remotely-located control devices enters a “power-cycled” state. Specifically, the 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.


At this time, the remote device discovery procedure 216, which is shown in FIG. 3, is executed by the repeater 122. The remote device discovery procedure 216 is performed on all “appropriate” control devices, i.e., those devices that are unaddressed, have not been found by the remote device discovery procedure (i.e., the FOUND flag is not set), and have recently had power cycled (i.e., the POWER_CYCLED flag is set). Accordingly, the remote device discovery procedure 216 must be completed before the “power-cycled” timer in each applicable control device expires.


Referring to FIG. 3, the remote device discovery procedure 216 begins at step 300. A variable M, which is used to determined the number of times that one of the control loops of the remote device discovery procedure 216 repeats, is set to zero at step 305. At step 310, the repeater 122 transmits a “clear found flag” message to all appropriate devices. When an unaddressed control device that has the POWER_CYCLED flag set receives the “clear found flag” message, the control device reacts to the message by clearing the FOUND flag. At step 312, the repeater 122 polls, i.e., transmits a query message to, a subset of the appropriate remote devices. The subset may be, for example, half of the appropriate remote devices, such as those unaddressed control devices that have not been found, have been recently power cycled, and have even serial numbers. The query message contains a request for the receiving control device to transmit an acknowledgement (ACK) message containing a random data byte in a random one of a predetermined number of ACK transmission slots, preferably 64 ACK transmission slots. The appropriate remote devices respond by transmitting the ACK message having a random data byte to the repeater 122 in a random ACK transmission slot. At step 314, if at least one ACK message is received, the repeater 122 stores the number of the ACK transmission slot and the random data byte from each ACK message in memory at step 316.


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 316). Specifically, at step 318, 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 0×A2 (hexadecimal). The repeater 122 waits to receive a serial number back from the device at step 320. When the repeater 122 receives the serial number, the serial number is stored in memory at step 322. At step 324, 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 320. 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 326, if all serial numbers have not been collected, the process loops around to request the serial number of the next control device at step 318.


Since collisions might have occurred when the remote devices were transmitting the ACK message (at step 314), the same subset of devices is polled again at step 312. Specifically, if all serial numbers have been collected at step 326, the process loops around to poll the same subset of devices again at step 312. If no ACK messages are received at step 314, the process flows to step 328. If the variable M is less than a constant MMAX at step 328, the variable M is incremented at step 330. To ensure that all of the devices in the first subset have transmitted an ACK message to the query at step 312 without a collision occurring, the constant MMAX is preferably two (2) such that the repeater 122 preferably receives no ACK messages at step 314 in response to transmitting two queries at step 312. If the variable M is not less than the constant MMAX at step 328, then a determination is made at step 332 as to whether there are more devices to poll. If so, the variable M is set to zero at step 334 and the subset of devices (that are polled in step 312) is changed at step 336. For example, if the devices having even serial numbers were previously polled, the subset will be changed to those devices having odd serial numbers. If there are no devices left to poll at step 332, the remote device discovery procedure exits at step 338.


Referring back to FIG. 2, at step 218, the repeater 122 compiles a list of serial numbers of all remote devices found in the remote device discovery procedure 216. At step 220, the user is presented with the option of either manually or automatically addressing the remote devices. If the user does not wish to manually address the remote devices, the remote devices are automatically assigned addresses in step 222, for example, sequentially in the order that the devices appear in the list of serial numbers of step 218. Otherwise, the user may manually assign addresses to the remote devices at step 224. For example, the user may use a graphical user interface (GUI) software provided on a personal computer (PC) that is operable to communicate with the RF lighting control system 100. Accordingly, the user may step through each device in the list of serial numbers and individually assign a unique address. After the remote devices are either automatically addressed at step 222, or manually addressed at step 224, the addresses are transmitted to the remote control devices at step 226. Finally, the user causes the lighting control system 100 to exit the addressing mode at step 228, e.g., by pressing and holding an actuator on the repeater 122 for a predetermined amount of time.


The step of cycling power to the remote devices, i.e., step 214, 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 will 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 will poll all unaddressed devices at step 312 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 as the remote device discovery procedure is completed before the “power-cycled” timer expires.


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 discover a remotely-located control device on a wired communication link.


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.

Claims
  • 1. A method for identifying a plurality of remote control devices having a unique identifier in an RF control system wherein a first device provides RF control signals to the plurality of remote control devices, the method comprising the steps of: transmitting a polling signal from the first device to one of the remote control devices;transmitting an acknowledgment signal from the one of the remote control devices to the first device in response to the polling signal;transmitting an identifier request signal to the one of the remote control devices from the first device using information related to the acknowledgement signal; andtransmitting the unique identifier from the one of the remote control devices to the first device in response to the identifier request signal.
  • 2. The method of claim 1, further comprising the steps of: transmitting from the first device to the remote control devices a clear signal to clear a found flag in a memory of each remote control device; andtransmitting a signal to the remote control device whose unique identifier has been received at the first device to set the found flag in the memory of the remote control device.
  • 3. The method of claim 1, further comprising the steps of: setting a power-cycled flag in a memory of the one of the remote control devices by cycling power from off to on to the one of the remote control devices; andthe one of the remote control devices responding to the polling signal only if the power-cycled flag has been set.
  • 4. The method of claim 1, wherein the unique identifier comprises a manufacturer serial number of the remote control device.
  • 5. The method of claim 1, wherein the information related to the acknowledgement signal comprises a random transmission slot and a random data byte
  • 6. The method of claim 1, further comprising the step of: storing information related to the acknowledgment signal in a memory of the first device.
  • 7. A method of discovering a first remotely-located control device in a control system having a plurality of control devices, the method comprising the steps of: transmitting a query message to the plurality of control devices;the first control device transmitting an acknowledgement message in response to the query message, the acknowledgement message transmitted in a random transmission slot and containing a random data byte; andidentifying the first control device by the random transmission slot and the random data byte.
  • 8. The method of claim 7, further comprising the steps of: requesting a serial number of the first control device; andthe first control device transmitting the serial number.
  • 9. The method of claim 7, further comprising the step of: transmitting a device address to the first control device.
  • 10. The method of claim 7, wherein the control system comprises a wireless control system.