CAN communication for building automation systems

• US 7,433,740 B2
• Filed: 12/16/2005
• Issued: 10/07/2008
• Est. Priority Date: 03/05/2003
• Status: Expired due to Term

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Colorado vNet, LLC
• Inventors: Hesse, Scott, Kiwimagi, Gary, Ogawa, Craig, Files, Craig
• Primary Examiner(s): Holmes; Michael B
• Application Number:
  US11/305,793
• Publication Number:
  US 20060095146A1
• Time in Patent Office: 1,026 Days
• Field of Search: 700/1
• US Class Current: 700/1
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence
• CPC Class Codes: G05B 2219/25032 CAN, canbus, controller area network bus
• CPC Class Codes: G05B 2219/25211 Broadcast mode, length message, command, address of originator and destination

Abstract

Systems and methods for implementing CAN communication for building automation systems are disclosed. An exemplary system may comprise at least one sending device linked to a plurality of receiving devices over a CAN automation network. A control frame may be broadcast over the CAN automation network by the at least one sending device, the control frame encapsulated into a CAN extended data frame. An acceptance filter may be provided at each of the plurality of receiving devices, each of the plurality of receiving devices reading the control frame from the CAN extended data frame and determining if the receiving device is a target device based on the control frame. Device communication may also be implemented as methods for dynamic address assignment and firmware download.

Claims

1. A building automation system comprising:

at least one sending device linked to a plurality of receiving devices over a CAN automation network;

a control frame broadcast over the CAN automation network by the at least one sending device, the control frame encapsulated into a CAN extended data frame, wherein the control frame includes one or more of a command packet for requesting the target device to execute an automation function, a command packet for requesting status information from the target device, and an event packet indicating only that an action occurred at the sending device; and

an acceptance filter at each of the plurality of receiving devices, each of the plurality of receiving devices reading the control frame from the CAN extended data frame and determining if the receiving device is a target device based on the control frame.

2. The building automation system of claim 1 wherein a single event identified in the event packet triggers action at a plurality of automation devices.

3. The building automation system of claim 1 wherein a single event identified in the event packet triggers action at a single automation device.

4. The building automation system of claim 1 further comprising a data frame broadcast over the CAN automation network by the at least one sending device, the data frame encapsulated into a CAN extended data frame for sending data between devices on the CAN automation network.

5. The building automation system of claim 4 wherein the control frame and data frame each include a destination field ID identifying an address of the target device.

6. The building automation system of claim 5 wherein the acceptance filter decodes the destination field ID to determine if the receiving device is the target device.

7. The building automation system of claim 4 wherein the control frame and data frame each include a source ID identifying an address of the sending device.

8. The building automation system of claim 7 wherein the target device returns data to the sending device using the source ID.

9. The building automation system of claim 7 wherein the target device returns either an ACK or NAK to the sending device using the source ID.

10. The building automation system of claim 1 wherein the control frame is issued as a priority message.