Communications: electrical – Continuously variable indicating – With meter reading
Reexamination Certificate
1998-07-28
2001-03-27
Zimmerman, Brian (Department: 2635)
Communications: electrical
Continuously variable indicating
With meter reading
C705S027200
Reexamination Certificate
active
06208263
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to methods for communicating in a control area network, and particularly to such methods in which a consumer of data transmitted on the network listens for a special instance of the data.
BACKGROUND OF THE INVENTION
In controlling various kinds of equipment in homes and buildings, the equipment is often connected to a network through which information is transmitted. Connecting the equipment together in a network system has the advantage that various parts of the system can “communicate” with each other, whereby the system works with maximum efficiency and potential inconsistencies, such as two parts of the system counteracting each other in operation, can be avoided.
A controller area network may, for example, be used for such purposes. Messages of variable length are transmitted in the network for controlling the system to operate according to provided algorithms. The message frame format includes an identifier at the beginning of each message which provides an identity for each message. The identity may, for example, relate to the kind of data transmitted in a data field of the message.
In a system including several similar producers of equivalent information, and including at least one ultimate consumer of the information produced by the producers, the system must facilitate that the consumer knows to which producers to listen. It is also important that the network is not overloaded with messages from those producers to which the consumer is not listening.
One way of arranging a system in accordance with the above would be to configure every producer particularly for its designated role in the system, and for the ultimate consumer to make use of addressing of the producers in the network. However, this method is undesirable in that it requires more initial programming and system configuration than is desirable for the typical home and building control system. Besides the additional work requirement, which may be inconvenient in a home or building environment, the costs of installation will likely increase with such a solution. Furthermore, the amount of information transmitted in the network may typically increase with this method, perhaps making the system harder to manage. An additional disadvantage is that producers cannot be added, and/or removed from the system without particular reconfiguration and/or readdressing of the producers.
SUMMARY OF THE INVENTION
A method of communication between at least one producer device and at least one consumer device in an environmental control network includes transmitting a message from the producer device on the network for receipt by the consumer device and other producing devices that may be present on the network, the message including at least a demand value monitoring the network at the producer device for any messages sent from other producer devices that may be present on the network, terminating further transmission of the message from the producer device if the producer device senses a message from another producer device with a greater demand value, and the consumer device responding to a demand value last received over the network and intended for receipt by the consumer device.
An embodiment of the method according to the invention involves a number of producer devices and a consumer device. A first producer device transmits a first message with a first value over the network. A second producer device compares the first value to a second value. If the second value is higher than the first value, the second producer device will transmit a second message over the network. The consumer device will respond to the last message it receives.
An environmental control network with a network bus includes at least one environmental condition sensing device connected to the network bus, wherein the sensing device including a transmitter for transmitting messages over the network including at least a demand value, means for monitoring the network bus at the sensing device for any messages sent from other sensing devices that may be present on the network, and means for terminating further transmission of the message from the producer device if the producer device senses a message from another producer device with a greater demand value, and at least one consumer device connected to the network bus, wherein the consumer device including means for responding to a demand value last received over the network bus.
These and various advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be used to the accompanying drawings and descriptive matter which form a further part hereof, and in which there is illustrated and described preferred embodiments of the invention.
REFERENCES:
patent: 5394324 (1995-02-01), Clearwater
patent: 5765138 (1998-06-01), Aycock et al.
patent: 5873069 (1999-02-01), Reuhl et al.
patent: 6076070 (2000-06-01), Stack
Honeywell International , Inc.
Leonard Robert B.
Zimmerman Brian
LandOfFree
Multiple value multiple owner message class does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multiple value multiple owner message class, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multiple value multiple owner message class will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2443106