APPROACH FOR DISCOVERING DEVICES ON A COMMON BUS WITHOUT DIRECT COMMUNICATION
First Claim
1. A system for discovering devices on a common BACnet bus without a direct communication path between a master and one or more of the other devices communicating on the common bus, comprising:
- a wired BACnet communication bus;
a host device;
at least two devices communicating on the wired communication bus, wherein the first device is connected to the host device and a second device is connected to the first device wherein the host communicates to the second device via the wired communication bus through the first device; and
wherein;
the host device transmits a message on the wired communication bus requesting a response from any device on the bus;
each device on the bus has a unique identification by which the device can be identified on the bus upon receiving a message from the host device;
a broadcasting of a first message transmitted by the host device indicates a range from a minimum designation to a maximum designation;
the minimum designation covers up to one unique designation of a device on the bus;
the maximum covers virtually all unique designations of devices on the bus;
one or no response from a device on the bus indicates no collision and that the message is not to be again sent by the host device for the range, wherein the range is greater than one and the unique identification of the responding device is within the range;
two or more responses from devices on the bus indicate a collision, and that the message is to be again sent by the host device to a portion of the range; and
two or more responses from devices on the bus having unique designations within the portion of the range indicate a collision and that the message is to be again sent by the host device to a portion of the portion of the range.
1 Assignment
0 Petitions
Accused Products
Abstract
A system for discovering devices on a common bus without direct communication. Each device on the bus has a unique identification. One of the devices or a computer may be a master or a host. The host may broadcast a request asking every device with an identification value in a particular range to respond. If no device or one device exists on the bus in this particular range, then there is no or one response, respectively. If multiple devices exist within the range, then multiple responses may be received by the host. In a case of multiple responses, the host may re-transmit its request to one or more half ranges. If multiple responses are again received, then the host may again re-transmit its request where the half range or ranges are again split in half. This approach of half-range reduction may be repeated until no more collisions occur.
19 Citations
20 Claims
-
1. A system for discovering devices on a common BACnet bus without a direct communication path between a master and one or more of the other devices communicating on the common bus, comprising:
-
a wired BACnet communication bus; a host device; at least two devices communicating on the wired communication bus, wherein the first device is connected to the host device and a second device is connected to the first device wherein the host communicates to the second device via the wired communication bus through the first device; and wherein; the host device transmits a message on the wired communication bus requesting a response from any device on the bus; each device on the bus has a unique identification by which the device can be identified on the bus upon receiving a message from the host device; a broadcasting of a first message transmitted by the host device indicates a range from a minimum designation to a maximum designation; the minimum designation covers up to one unique designation of a device on the bus; the maximum covers virtually all unique designations of devices on the bus; one or no response from a device on the bus indicates no collision and that the message is not to be again sent by the host device for the range, wherein the range is greater than one and the unique identification of the responding device is within the range; two or more responses from devices on the bus indicate a collision, and that the message is to be again sent by the host device to a portion of the range; and two or more responses from devices on the bus having unique designations within the portion of the range indicate a collision and that the message is to be again sent by the host device to a portion of the portion of the range. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for discovering devices on a BACnet communication bus, comprising:
-
transmitting a broadcast message on a wired communication bus for virtually all devices including devices having unique identifications within a range which comprises the unique identifications;
whereina device broadcasts a response message if the device has a unique identification that matches an identification within the range; if more than one device broadcasts a response message, then there is a collision; if only one device broadcasts a response message, then there is just one device within the range; and if no device broadcasts a response message, then there is no device within the range; and assigning a second unique identifier to each identified device when the identified device is the only one device that broadcasted a response within the range, wherein the second unique identifier is used for Master slave/token passing (MS/TP) communications via the wired communication bus. - View Dependent Claims (9, 10, 11, 12, 13)
-
-
14. A method for discovering devices on a communications bus, comprising:
-
providing a host that transmits a message on a bus; and assigning a communication identifier to the responding device when only one device responds to transmitted message; and
wherein;one or more devices are connected to the bus, wherein one device is wired to the host and each device is wired to at least one other device on the bus; each device on the bus has a unique identification; the message transmitted on the bus is to each device having an identification within a range of identifications; a device that receives the message provides a response to the message; and if a response is provided by more than one device, then the host transmits the message on the bus to devices within a portion of the range of identifications, and if another response is provided by more than one device, the host further transmits the message on the bus to devices within a portion of the portion of the range of identifications, and so on, until a response is provided by one or no device. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
Specification