Signaling between master and slave components using a shared communication node of the master component

• US 9,634,715 B2
• Filed: 03/12/2015
• Issued: 04/25/2017
• Est. Priority Date: 02/18/2014
• Status: Active Grant

• Current Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Original Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Inventors: Scheinkerman, Ricardo, Kozomora, Nevenka, Doogue, Michael C., Vreeland, Richard
• Primary Examiner(s): Corrielus, Jean B
• Application Number:
  US14/645,946
• Publication Number:
  US 20150236746A1
• Time in Patent Office: 775 Days
• CPC Class Codes: G06F 3/00 Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements

Abstract

A network slave device includes a transceiver for communicating over a communication bus in accordance with a point-to-point network protocol. The network slave device may have an address to identify the network slave device on the network. It may also have a communication circuit configured to process a series of commands received by the transceiver and respond to a command if a position of the command in the series of commands corresponds to the address of the network slave device. A master device communicating on the network may send the series of command in accordance with the point-to-point network protocol. In an embodiment, the point-to-point protocol is the SENT protocol.

Claims

1. A network slave device comprising:

a transceiver for communicating over a communication bus in accordance with a point-to-point network protocol;

a communication circuit configured to process a series of commands received by the transceiver and respond to a command if a position of the command in the series of commands corresponds to an address of the network slave device, wherein the address identifies the network slave device; and

a counter configured to count the number of commands sent by a master device, wherein the network slave device is configured to reset the counter when a number of commands received meets or exceeds a number of slave devices coupled to the communication bus.

2. The network slave device of claim 1 wherein the point-to-point communication protocol is a Single-Edge Nibble Transmission (SENT) protocol.

3. The network slave device of claim 1 further comprising a memory, wherein the address is stored in the memory.

4. The network slave device of claim 1 wherein the slave device comprises a magnetic field sensor.

5. The network slave device of claim 4 wherein the magnetic field sensor comprises magnetic field sensing elements.

6. The network slave device of claim 5 wherein the magnetic field sensing elements comprise Hall effect elements.

7. The network slave device of claim 5 wherein the magnetic field sensing elements comprise magnetoresistive elements.

8. The network slave device of claim 7 wherein the magnetoresistive elements comprise a giant magnetoresistance (GMR) element, a tunneling magnetoresistance (TMR) element, a magnetic tunnel junction (MTJ) element, a spin-valve, or a combination thereof.

9. The network slave device of claim 4 wherein the commands comprise requests for data representing a magnetic field detected by the magnetic field sensor.

10. The network slave device of claim 1 further configured to respond to a reset command by resetting the counter.

11. The network slave device of claim 1 wherein the commands include one or more of:

a sample command to perform a measurement;

a data request command to send measurement data;

a diagnostic command perform a self-test;

a reset command to reset the counter;

or a combination thereof.

12. The network slave device of claim 11 wherein the sample command comprises a pulse of one predetermined length, the diagnostic command comprises a pulse of a second predetermined length;

the data request command comprises a pulse of a third predetermined length; and

the reset command comprises a pulse of a fourth predetermined length.

13. The network slave device of claim 1 wherein the commands comprise broadcast commands.

14. The network slave device of claim 13 wherein the broadcast commands include one or more of:

a sample command to perform one or more respective measurements;

a diagnostic command to perform one or more respective self-tests;

a reset command to reset the counter of the slave device;

or a combination thereof.

15. The network slave device of claim 1 further configured to delay sending a response to the commands by a delay time period corresponding to the address of the slave device.

16. A network slave device comprising:

a transceiver for communicating over a communication bus in accordance with a point-to-point network protocol;

a communication circuit configured to process a series of commands received by the transceiver and respond to a command if a position of the command in the series of commands correspond to an address of the network slave device, wherein the address identifies the network slave device; and

wherein the network slave device is configured to read a delay time period of a response from another network slave device and determine a current position in the series of commands based on the delay time period.

17. A system comprising:

a controller coupled to a communication bus and configured to communicate over the communication bus in accordance with a point-to-point communication protocol to send a series of commands over the communication bus; and

one or more sensors coupled to the communication bus to communicate over the communication bus in accordance with the point-to-point communication protocol, each of the sensors having a respective address to identify the respective sensor and configured to respond to a command in the series of commands that has a position within the series that matches the respective address of the respective sensor;

wherein the one or more sensors each comprise a counter configured to count the number of commands sent by the controller, and wherein the one or more sensors are configured to reset their counters when a number of commands sent by the controller matches or exceeds a number of sensors coupled to the communication device.

18. The system of claim 17 wherein the controller and the one or more sensors are configured to communicate over the communication bus in accordance with the point-to point communication protocol.

19. The system of claim 18 wherein the point-to-point communication protocol is a Single-Edge Nibble Transmission (SENT) protocol.

20. The system of claim 17 wherein the one or more sensors are magnetic field sensors.

21. The system of claim 20 wherein the commands comprise requests for data representing a magnetic field detected by at least one of the magnetic field sensors.

22. The system of claim 17 wherein the controller is configured to send a reset command which, when received by the one or more sensors, resets the counters of the one or more sensors.

23. The system of claim 17 wherein each respective sensor is configured to respond to the commands when a counter of the respective sensor matches the address of the respective sensor.

24. The system of claim 17 wherein the commands include one or more of:

a sample command to perform a measurement;

a diagnostic command perform a self-test; and

a reset command to reset the counter.

25. The system of claim 24 wherein the sample command comprises a pulse of one predetermined length, the diagnostic command comprises a pulse of a second predetermined length;

and the reset command comprises a pulse of a third predetermined length.

26. The system of claim 17 wherein the controller is further configured to send broadcast commands to all the sensors coupled to the communication bus.

27. The system of claim 26 wherein the broadcast commands comprise commands that do not include an address.

28. The system of claim 26 wherein the broadcast commands include one or more of:

a sample command instructing all the respective sensors to perform one or more respective measurements;

a diagnostic command instructing all the respective sensors to perform one or more respective self-tests; and

a reset command instructing all the respective sensors to reset the respective counters of the respective sensors.

29. The system of claim 17 wherein the sensors are configured to delay sending a response to the commands by a time period corresponding to the address of the sensors.

30. A system comprising:

a controller coupled to a communication bus and configured to communicate over the communication bus in accordance with a point-to-point communication protocol to send a series of commands over the communication bus; and

one or more sensors coupled to the communication bus to communicate over the communication bus in accordance with the point-to-point communication protocol, each of the sensors having a respective address to identify the respective sensor and configured to respond to a command in the series of commands that has a position within the series that matches the respective address of the respective sensor;

wherein the one or more sensors are configured to read a delay time period of a response from another sensor and determine a current position in the series based on the delay time period.

31. A method comprising:

sending a series of commands by a master device coupled to a one-wire communication bus;

responding to one of the commands, by a selected slave device of one or more slave devices, if a position of the command in the series of commands matches an address of the selected slave device;

sending, by the master device, a reset command which, when received by the one or more slave devices, resets respective counters of the one or more slave devices; and

restarting, by the one or more slave devices, a respective count when a number of commands sent by the master device matches or exceeds a number of slave devices coupled to the communication device.

32. The method of claim 31 wherein the master device and the one or more slave devices are configured to communicate over the communication bus in accordance with a point-to point communication protocol.

33. The method of claim 32 wherein the point-to-point communication protocol is a Single-Edge Nibble Transmission (SENT) protocol.

34. The method of claim 31 wherein the one or more slave devices are magnetic field sensors.

35. The method of claim 34 wherein sending the series of commands comprises sending requests for data representing a magnetic field detected by at least one of the magnetic field sensors.

36. The method of claim 31 further comprising counting the commands by the one or more slave devices coupled to the communication bus.

37. The method of claim 36 wherein counting the commands comprises incrementing the respective counters of the one or more slave devices.

38. The method of claim 31 wherein the sending the commands include sending one or more of:

a sample command to perform a measurement;

a data request command to send measurement data;

a diagnostic command to perform a self-test; and

a reset command to reset the counter.

39. The method of claim 38 wherein sending the sample command comprises sending a pulse of one predetermined length, sending the diagnostic command comprises sending a pulse of a second predetermined length;

sending the data request command comprises sending a pulse of a third predetermined length; and

sending the reset command comprises sending a pulse of a fourth predetermined length.

40. The method of claim 31 further comprising sending broadcast commands to all the slave devices coupled to the communication bus.

41. The method of claim 40 wherein the broadcast commands comprise commands that do not include an address.

42. The method of claim 40 wherein sending the broadcast commands includes sending one or more of:

a sample command instructing all the respective slave devices to perform one or more respective measurements;

a diagnostic command instructing all the respective slave devices to perform one or more respective self-tests; and

a reset command instructing all the respective slave device to reset the respective counters of the respective slave devices.

43. The method of claim 31 wherein responding comprises delaying sending a response to the commands by a delay time period corresponding to the address of the selected slave device.

44. A method comprising:

sending a series of commands by a master device coupled to a one-wire communication bus;

reading, by at least one network slave device, a delay time period of a response from another network slave device and determining a current position in the series of commands based on the delay time period and

responding to one of the commands, by the at least one network slave device, if the current position of the command in the series of commands matches an address of the at least one network slave device.