Systems and methods to detect bus network fault and topology

• US 9,037,918 B2
• Filed: 08/18/2014
• Issued: 05/19/2015
• Est. Priority Date: 06/15/2011
• Status: Active Grant

• Current Assignee: Digital Lumens, Inc. (Ams-Osram AG)
• Original Assignee: OSRAM Sylvania Inc. (Ams-Osram AG)
• Inventors: Hoffknecht, Marc, Rojas, Javier, O'Hagan, Liam John
• Primary Examiner(s): Wilson, Yolanda L
• Application Number:
  US14/461,777
• Publication Number:
  US 20140359373A1
• Time in Patent Office: 274 Days
• Field of Search: None
• US Class Current: 714/43
• CPC Class Codes: G06F 11/0745 in an input/output transactions management context input/output processing in general G06F13/00
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/221 to test buses, lines or interfaces, e.g. stuck-at or open line faults
• CPC Class Codes: G06F 11/3027 where the computing system component is a bus
• CPC Class Codes: H04L 1/24 Testing correct operation
• CPC Class Codes: H04L 2001/0094 Bus

Abstract

Systems for helping identify faults on a bus, as well as to determine the topology of a bus network, are disclosed. A system according to one embodiment includes a bus interface for connecting to a bus and a switch coupled to the bus interface, the switch configured to alternate between an open state and a closed state. The system is connected to the bus via the bus interface when the switch is in the closed state, and the system is disconnected from the bus via the bus interface when the switch is in the open state.

Claims

1. A device comprising:

a bus interface to connect the device to a bus;

a transceiver to transmit and receive data via the bus over the bus interface; and

a fault isolation switch connected to the bus interface, where the fault isolation switch has an open state and a closed state, such that when the fault isolation switch is in the open state, the bus interface is disconnected from the bus and the transceiver is unable to transmit or receive data via the bus, and when the fault isolation switch is in the closed state, the bus interface is connected to the bus and the transceiver is able to transmit and receive data via the bus, wherein the fault isolation switch further comprises a fault detection circuit, wherein the fault detection circuit is configured to identify a fault associated with the bus, to alternate the fault isolation switch to the open state in response to identifying the fault;

wherein the transceiver is configured to transmit data via the bus upon the fault isolation switch changing from the open state to the closed state to indicate a location of the device on the bus.

2. The device of claim 1, wherein the fault isolation switch further comprises:

a first connector and a second connector;

a first switch and a second switch;

a capacitor, a resistor, and a Zener diode in parallel with each other and connected between the first switch and the second switch; and

a charge pump;

wherein the charge pump is configured, upon activation, to charge the capacitor, turning the first switch and the second switch on, and thus turning on the fault isolation switch, and upon deactivation, to allow the capacitor to discharge through the resistor, turning the first switch and the second switch off, and thus turning off the fault isolation switch.

3. The device of claim 1, wherein the fault detection switch has an initial operation mode and a steady operation mode, and the fault detection switch is configured to default to the open state while in the initial operation mode.

4. The device of claim 1, wherein the fault isolation switch is configured to alternate between the open state and the closed state in response to a signal received from the bus via the bus interface.

5. The device of claim 4, wherein the fault isolation switch is configured to remain in the open state or the closed state until receipt of a second signal from the bus via the bus interface.

6. The device of claim 1, further comprising a microcontroller, wherein the microcontroller is configured to control the device and to provide output signals to a further device to which the device is connected.

7. The device of claim 6, wherein the microcontroller is further configured to provide the data to the transceiver to indicate the location of the device on the bus.

8. A system, comprising:

a system bus;

a power supply connected to the system bus;

a plurality of devices connected to the system bus, wherein each device in the plurality of devices includes;

a bus interface to connect the device to a bus;

a transceiver to transmit and receive data via the bus over the bus interface; and

a fault isolation switch connected to the bus interface, wherein the fault isolation switch has an open state and a closed state, such that when the fault isolation switch is in the open state, the bus interface is disconnected from the bus and the transceiver is unable to transmit or receive data via the bus, and when the fault isolation switch is in the closed state, the bus interface is connected to the bus and the transceiver is able to transmit and receive data via the bus, wherein the fault isolation switch comprises;

a first connector and a second connector;

a first switch and a second switch;

a capacitor, a resistor, and a Zener diode in parallel with each other and connected between the first switch and the second switch; and

a charge pump;

wherein the charge pump is configured, upon activation, to charge the capacitor, turning the first switch and the second switch on, and thus turning on the fault isolation switch, and upon deactivation, to allow the capacitor to discharge through the resistor, turning the first switch and the second switch off, and thus turning off the fault isolation switch;

a luminaire, wherein the luminaire comprises a light source to provide illumination and a lighting power source to provide power to illuminate the light source, and wherein the luminaire is connected to a device in the plurality of devices, such that operation of the luminaire is controlled by the connected device;

wherein the transceiver of each device in the plurality of devices is configured to transmit data via the bus upon the fault isolation switch changing from the open state to the closed state to indicate a location of that device and the luminaire to which that device is connected on the bus; and

a control device, comprising;

a bus interface to connect the control device to the system bus;

a communications device connected to the system bus through the bus interface, the communications device configured to transmit and receive data via the bus interface;

a processor connected to the bus interface and the communications device; and

a memory system connected to the processor, wherein the memory system stores instructions that, when executed by the processor, cause the control device to perform operations of;

receiving, from the system bus by the communications device via the bus interface, a communication from a device in the plurality of devices that is connected to the luminaire;

validating the communication to produce an action result;

in response, based on the action result, transmitting a command to the device in the plurality of devices that is connected to the luminaire that causes the luminaire to generate a visual indicator via the light source of the luminaire;

receiving, from the system bus by the communications device via the bus interface, data from a set of transceivers of a set of devices in the plurality of devices indicating the locations of the set of devices and the luminaires to which the set of devices are connected; and

determining a wiring topology of the system from received data.

9. The system of claim 8, wherein transmitting comprises:

in response, based on the action result, transmitting a command to the device in the plurality of devices that is connected to the luminaire that causes the luminaire to generate a visual indicator by alternately activating and de-activating the light source of the luminaire.

10. The system of claim 8, wherein validating comprises:

validating the communication to produce an action result, wherein the action result includes a command to device in the plurality of devices that is connected to the luminaire, wherein the command will cause the device to control the luminaire to generate a visual indicator via the light source of the luminaire;

and wherein transmitting comprises;

in response, transmitting the command in the action result to the device in the plurality of devices that is connected to the luminaire, such that the device controls the luminaire according to the transmitted command.

11. The system of claim 8, further comprising:

a lighting control device that is configured to receive input, wherein the lighting control device is connected to the luminaire, such that operation of the luminaire may be controlled by the lighting control device, the device in the plurality of devices connected to the luminaire, or both the lighting control device and the device in the plurality of devices connected to the luminaire, and wherein the lighting control device is connected to a device in the plurality of devices, such that operation of the lighting control device may be controlled by the received input, the connected device, or both the received input and the connected device;

and wherein the memory system stores instructions that, when executed by the processor, cause the control device to perform operations of;

receiving, from the system bus by the communications device via the bus interface, a communication from the device in the plurality of devices that is connected to the lighting control device;

validating the communication to produce an action result; and

in response, based on the action result, transmitting a command to the device in the plurality of devices that is connected to the luminaire that causes the luminaire to operate based on the transmitted command to generate a visual indicator.

12. The system of claim 11, wherein transmitting comprises:

in response, based on the action result, transmitting a command to the device in the plurality of devices that is connected to the lighting control device that causes the lighting control device to operate the luminaire based on the transmitted command to generate a visual indicator.

13. A method comprising:

coupling a first set of devices to a bus, wherein each device in the first set of devices comprises;

a bus interface to connect the device to a bus;

a transceiver to transmit and receive data via the bus over the bus interface; and

a fault isolation switch connected to the bus interface, wherein the fault isolation switch has an open state and a closed state, such that when the fault isolation switch is in the open state, the bus interface is disconnected from the bus and the transceiver is unable to transmit or receive data via the bus, and when the fault isolation switch is in the closed state, the bus interface is connected to the bus and the transceiver is able to transmit and receive data via the bus, wherein the fault isolation switch comprises;

a first connector and a second connector;

a first switch and a second switch;

a capacitor, a resistor, and a Zener diode in parallel with each other and connected between the first switch and the second switch; and

a charge pump;

wherein the charge pump is configured, upon activation, to charge the capacitor, turning the first switch and the second switch on, and thus turning on the fault isolation switch, and upon deactivation, to allow the capacitor to discharge through the resistor, turning the first switch and the second switch off, and thus turning off the fault isolation switch;

coupling a second set of devices to the bus, wherein each device in the second set of devices comprises a luminaire comprising a light source to provide illumination and a lighting power source to provide power to illuminate the light source;

connecting at least one device in the first set of devices with a subset of devices in the second set of devices;

transmitting, from the transceiver of each device in the first set of devices, indication data, via the bus upon the fault isolation switch of that device changing from the open state to the closed state, to indicate a location of that device and the subset of devices in the second set of devices connected thereto; and

determining, from the transmitted indication data, a wiring topology of the first set of devices and the second set of devices.

14. The method of claim 13, wherein determining comprises:

monitoring a sequence of the transmitted indication data via the bus to determine the device in the first set of devices that transmitted the indication data; and

using the monitored sequence and the indication data to determine a wiring topology of the first set of devices and the second set of devices.

15. The method of claim 13, further comprising:

coupling a power supply to the bus;

measuring at least one of a current and a voltage on a bus in response to receiving indication data via the bus by a device in the first set of devices;

calculating a wiring impedance between the power supply and the device; and

determining a distance between the power supply and the device based on the calculated wiring impedance.

16. The method of claim 15, further comprising;

adjusting the at least one measured current and measured voltage by an offset, the offset based on one or more characteristics of the device in the first set of devices.

17. The method of claim 13, further comprising:

transmitting a communication via the bus to the first set of devices coupled to the bus;

receiving one or more response communications via the bus from a first subset of the first set of devices in the plurality of devices;

based on the received one or more response communications and the determined wiring topology, identifying a second subset of the first set of devices from which a response communication was not received via the bus; and

using the received one or more response communications, the determined wiring topology, and the identified second subset of the first set of devices in the plurality of devices to locate a fault on the bus.