COMMUNICATIONS VIA DATA BUSES

Abstract

Apparatus (101) for providing communication between buses (303, 303A, 303B, 303C, 303D) in a vehicle (305), the apparatus (101) comprising control means (102, 202), storage means (104, 205) for storing data, and communication means (105, 203) for transmitting and receiving signals via a plurality of data buses, the apparatus (101) further being configured to: Receiving a request for partial network operation; Selecting at least one of a plurality of buses (303, 303A, 303B, 303C, 303D) based on a received request for partial network operation; and depending on the satisfaction of a set of conditions (701-705) for partial network operation, causing network management signals to be provided to the at least one selected bus (303, 303A, 303B, 303C, 303D) to maintain nodes (302) on the at least one selected bus (303, 303A, 303B, 303C, 303D) in an awake state while allowing (a) node (302) on at least one other bus to enter a power saving mode.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to communications via data buses, particularly, but not limited to, communications via data buses in a vehicle.

[0002] Aspects of the invention relate to a device, an electronic control unit, a communication network, a vehicle, a method, a computer program and a non-transient computer-readable medium. STATE OF THE ART

[0003] Vehicles may contain multiple data buses, which may be interconnected via a central gateway and provide communication between the vehicle's electronic control units (ECUs). Functions performed by the ECUs may require communication over the data buses. If communication requires all ECUs connected to the buses to remain awake for the purposes of communication, energy will be consumed by each ECU, even if the communication is not relevant to it. Thus, energy is consumed by keeping ECUs awake when they are not needed.

[0004] The document DE 10 2012 014 724 B3 describes a concept for operating a data bus system of a motor vehicle, which has a plurality of data bus segments, wherein at least one of the data bus segments is designed to switch from an awake state to an idle state, and vice versa. In a first step, a communication requirement of a first control unit of a first data bus segment in the idle state is determined. Thereupon, if the communication requirement of the first control unit is determined, initially only the first data bus segment is brought from the idle state to the awake state. If the communication requirement of the first control unit with a second control unit outside the first data bus segment is determined, after the first data bus segment has been woken up, all other data bus segments of the data bus system outside the first data bus segment that are in the idle state are also woken up as a blanket process.

[0005] It is an object of the present invention to provide a solution that saves energy. SUMMARY OF THE INVENTION

[0006] Inventive aspects and embodiments relate to an apparatus, an electronic control unit, a communication network, a vehicle, a method, a computer program and a non-transient computer-readable medium as claimed in the appended claims.

[0007] According to one aspect of the invention, an apparatus is provided for providing communication between buses in a vehicle, the apparatus comprising control means, storage means for storing data, and communication means for transmitting and receiving signals over a plurality of data buses, the control means being configured to: determine at least one selected bus with respect to a received request for partial network operation, and dependent on the fulfillment of a set of conditions for partial network operation, cause network management signals to be provided to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state while allowing node(s) on at least one other bus to enter a power saving mode.

[0008] The control means may comprise a control device, optionally with at least one processor for providing network management. The storage means may comprise at least one storage device, and the communication means may comprise at least one transceiver for communicating via one or more data buses.

[0009] This provides the advantage of enabling communication between nodes in an interconnected network while conserving power by allowing the nodes on the at least one other bus to enter a power saving mode. This means allowing the nodes on the at least one bus to enter a power saving mode in which the main processor of a node is allowed to enter a low-power mode while the transceiver is not transmitting or receiving data. In this power saving mode, the transceiver can detect activity on the bus and, in response to detecting power, initiate a wake-up operation to wake up the main processor and begin transmitting and / or receiving data.

[0010] In one embodiment, the control means is configured to determine whether a network management message has been received without a request for partial network operation; and, depending on receiving a network management message without a request for partial network operation, cause network management signals to be provided to keep (a) node on all connected buses in an awake state. This allows all nodes to be kept in an awake state when necessary, for example, for security reasons.

[0011] In one embodiment, the control means is configured to: determine a set of selected buses required to provide partial network operation for each of a plurality of partial network requests; and perform a logical OR function on the sets of selected buses to determine the at least one selected bus. This allows the device to minimize the number of buses kept awake when multiple functions are to be executed that require communication over a network, while simultaneously providing a means of communication to the required buses.

[0012] In one embodiment, the set of partial network operation conditions comprises a plurality of partial network operation conditions, and the control means is configured to determine whether all partial network operation conditions are met.

[0013] In some embodiments, the condition(s) for partial network operation include the absence of a current request for network operation without partial network operation. This ensures that all nodes are kept awake when functions are to be performed that require it; when communication related to such a function is required, all nodes are kept awake.

[0014] In some embodiments, the condition(s) for partial network operation include a vehicle ignition switch being in a off state. This ensures that all nodes are in an awake state when the vehicle's engine is running or is about to be running.

[0015] In some embodiments, the control means is configured to determine whether a request for partial network operation received from a node is valid by determining whether a network management message has also been received from the same node. This allows a potentially erroneously received request for partial network operation to be ignored.

[0016] In some embodiments, the control means is configured to: provide network management signals to maintain nodes in the at least one selected bus and in the at least one other bus in an awake state for a predetermined period of time; and thereafter, enable (a) node in the at least one other bus to enter a power-saving mode while simultaneously further providing network management signals to the at least one selected bus to maintain nodes in the at least one selected bus in an awake state. By initially maintaining both the nodes in the selected bus and nodes in the at least one other bus, this enables all of these nodes to update stored data before powering down, rather than just selected nodes and selected data. Furthermore, this means that the vehicle's network will continue to wake up and shut down in the same way.

[0017] In some embodiments, the control means is configured to: receive a request for partial networking that identifies a function to be performed; and determine the at least one selected bus by retrieving at least one bus identifier corresponding to the function to be performed from the storage means. This allows the device to easily identify buses for communication in partial networking without requiring further input from the source of the request.

[0018] In some embodiments, the control means is configured to: receive a first request for partial network operation defining a first function to be performed and a second request for partial network operation defining a second function to be performed; retrieve at least one first bus identifier corresponding to the first function to be performed and retrieve at least one second bus identifier corresponding to the second function to be performed; and perform a logical OR function on the first and second bus identifiers to determine the at least one selected bus for the requested partial network operation. This allows the device to minimize the number of buses kept awake when multiple functions to be performed that require communication over a network are to be performed.

[0019] In some embodiments, the control means is configured to: monitor changes in the status of network operation requests; and, depending on a change in the status of network operation requests, provide network management signals to all buses to put nodes into a wake-up state. This ensures that nodes in the network are promptly brought into a wake-up state to act in accordance with the change in network operation requests.

[0020] In some embodiments, the control means comprises a control device configured to provide network management, the storage means comprises at least one storage device means, such as a memory device, and the communication means comprises at least one transceiver configured to communicate over a plurality of data buses.

[0021] In some embodiments, the device includes a central gateway.

[0022] According to one aspect of the invention, an electronic control unit for a vehicle is provided, the electronic control unit comprising: a control means for controlling a system in a vehicle and a communication means for communicating via a bus, the electronic control unit being configured to: determine that a first function to be executed is executable with partial network operation; depending on the first function to be executed being executable with partial network operation, transmit a network management message; and transmit a request for partial network operation.

[0023] The control means may comprise a control device, optionally with at least one processor. The communication means may comprise at least one transceiver for communicating via one or more data buses.

[0024] This provides the advantage that the electronic control means is able to communicate over a network while allowing nodes on at least one bus to enter a power saving mode during the communication process, thereby saving energy.

[0025] In some embodiments, the request for partial network operation includes a message identifying the first function to be performed. This allows a receiving gateway to identify the buses required for communication for the first function to be performed.

[0026] In some embodiments, the electronic control unit is configured to: determine whether both the first function to be performed and the second function to be performed are executable with partial network operation; and, depending on both the first function to be performed and the second function to be performed being executable with partial network operation, transmit one or more requests for partial network operation identifying the first function to be performed and the second function to be performed.

[0027] In some embodiments, the electronic control unit is configured to: determine that a further function to be performed is not executable with partial network operation; and, depending on the further function to be performed not being executable with partial network operation, transmit a network management message without a request for partial network operation to require that all buses be kept awake. This minimizes communication from the electronic control unit when partial network operation is not possible and may reduce subsequent processing by a gateway receiving the network management message.

[0028] In some embodiments, the electronic control unit is an engine control unit or a powertrain control unit, and the first function to be performed comprises communication related to battery charging. This has the advantage of saving energy during battery charging. Accordingly, the invention is particularly advantageous in vehicles in which at least part of the drive energy is electrical energy stored in a battery. For example, it is particularly advantageous in electric vehicles and hybrid electric vehicles.

[0029] In some embodiments, the control means comprises a control device for controlling a system in a vehicle, and the communication means comprises a transceiver configured to communicate via a bus.

[0030] According to one aspect of the invention, a communication network for a vehicle is provided, comprising a device according to one of the preceding aspects of the invention, operatively connected to a plurality of nodes via a plurality of buses.

[0031] In some embodiments, at least one of the nodes is an electronic control unit as claimed in the claims.

[0032] According to one aspect of the invention, a vehicle is provided with a communication network as claimed in the claims.

[0033] According to one aspect of the invention, there is provided a method for communicating across multiple buses in a vehicle, the method comprising: determining at least one selected bus with respect to a received request for partial network operation; and contingent upon satisfaction of a set of conditions for partial network operation, providing a network management signal to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state while allowing node(s) on at least one other bus to enter a power saving mode.

[0034] In some embodiments, the method comprises determining whether a request for network management without partial network operation has been received; and, responsive to receiving a request for network management without partial network operation, maintaining nodes on the at least one further bus in an awake state. In some embodiments, maintaining all buses in an awake state responsive to receiving a request for network management without partial network operation.

[0035] In some embodiments, the method comprises: determining a first set of selected buses required to provide the requested partial network operation for a partial network operation request; determining a second set of selected buses required to provide partial network operation for a second partial network operation request; and performing a logical OR function on the first set and the second set to determine the at least one selected bus to which network management signals are provided.

[0036] In some embodiments, the set of partial network operation conditions includes multiple partial network operation conditions, and one of the partial network operation conditions includes a vehicle ignition switch being in an off state.

[0037] In some embodiments, the method comprises: providing network management signals to maintain nodes in the at least one selected bus and in the at least one other bus in an awake state for a predetermined period of time; and thereafter, allowing nodes in the at least one other bus to transition to a power saving mode.

[0038] In some embodiments, the method comprises: receiving a request for partial network operation identifying a function to be performed; and retrieving stored bus identifiers corresponding to the function to be performed identified in the request for partial network operation to determine the at least one selected bus.

[0039] In some embodiments, the method comprises: determining a set of selected buses required to provide partial network operation for each of a plurality of partial network requests; and performing a logical OR function on the sets of selected buses to determine the at least one selected bus.

[0040] According to one aspect of the invention, there is provided a non-transient computer-readable medium comprising a set of computer instructions which, when executed, cause a computer to perform the method according to any one of the preceding aspects of the invention.

[0041] According to one aspect of the invention, there is provided a computer program that, when executed on a processor, effects communication between a plurality of buses in a vehicle, comprising: determining at least one selected bus with respect to a received request for partial network operation; and contingent upon satisfaction of a set of conditions for partial network operation, providing a network management signal to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state while allowing at least one node on at least one other bus to enter a power saving mode.

[0042] According to one aspect of the invention, an apparatus is provided for providing communication between buses in a vehicle, the apparatus comprising a controller, a storage device for storing data, and a transceiver for transmitting and receiving signals over a plurality of data buses, the controller being configured to: determine at least one selected bus with respect to a received request for partial network operation; and, contingent upon the fulfillment of a set of partial network operation conditions, cause network management signals to be provided to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state while allowing at least one node on at least one other bus to enter a power-saving mode. The controller may comprise one or more electronic processors.

[0043] According to one aspect of the invention, there is provided an electronic control unit for a vehicle, the electronic control unit comprising: a control device for controlling a system in a vehicle and a transceiver configured to provide communication via a bus, the electronic control unit being configured to: determine that a first function to be performed is executable with partial network operation; depending on the first function to be performed being executable with partial network operation, transmit a request for network management to a gateway; and transmit a request for partial network operation to the gateway.

[0044] According to one aspect of the invention, an apparatus is provided for providing communication between buses in a vehicle, the apparatus comprising control means, storage means for storing data, and communication means for transmitting and receiving signals over a plurality of data buses, the control means being configured to: determine at least one selected bus with respect to a received request for partial network operation, and dependent on the fulfillment of a set of conditions for partial network operation, cause network management signals to be provided only to the at least one selected bus to keep nodes on the at least one selected bus in an awake state.

[0045] According to one aspect of the invention, an apparatus is provided for providing communication between buses in a vehicle, the apparatus comprising a controller, a memory for storing data, and a transceiver for transmitting and receiving signals over a plurality of data buses, the controller being configured to: determine at least one selected bus with respect to a received request for partial network operation, and dependent on the fulfillment of a set of conditions for partial network operation, cause network management signals to be provided only to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state.

[0046] According to one aspect of the invention, an electronic control unit for a vehicle is provided, the electronic control unit comprising: a control device for controlling a system in a vehicle and a transceiver configured to provide communication via a bus, the electronic control unit being configured to: determine that a first function to be performed is executable with partial network operation; depending on the first function to be performed being executable with partial network operation, transmit a request for network management to a gateway.

[0047] The device may be used to provide a gateway between buses in a vehicle's network.

[0048] Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples, and alternatives presented in the preceding paragraphs, in the claims, and / or in the following description and drawings, and in particular their individual features, may be considered independently of one another or in any combination. This means that all embodiments and / or features of any embodiment may be combined in any manner and / or combination, provided these features are not incompatible.The applicant reserves the right to amend any originally filed claim or to file any new claim accordingly, including the right to amend any originally filed claim to depend on and / or incorporate any feature of any other claim even though it has not been so claimed before. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 a device 101; Fig. 2 an electronic control unit (ECU) 201 for a vehicle; Fig. 3 schematically shows an example of a network 301 in a vehicle 305 that includes the device 101; Fig. 4 is a flowchart of a method 400 performed by a node 302, such as the ECU 201; Fig. 5 is a flowchart of a second method 500 executable by a node 302, such as the ECU 201; Fig. 6 a flowchart of a method 600 executable by the device 101 of Fig. 1; Fig. 7 is a flowchart for an exemplary method 700 for determining whether all conditions for partial network operation are met; Fig. 8 is a flowchart of another exemplary method 800 executable by the device 101; Fig. 9 is a flowchart for an exemplary process of block 804 of Fig. 8; Fig. 10 is a flowchart of another exemplary method 1000 executable by the device (or gateway) 101; and Fig. 11 shows an example of a lookup table 108 stored by the device 101. DETAILED DESCRIPTION

[0050] The figures show an apparatus 101 for providing communication between buses in a vehicle, the apparatus comprising control means 102, storage means 104 for storing data and communication means 105 for transmitting and receiving signals via a plurality of data buses, the control means 102 being configured to: determine at least one selected bus with reference to a received request for partial network operation and, depending on the fulfillment of a set of conditions 701, 702, 703, 704, 705 for partial network operation, to cause network management signals to be provided to the at least one selected bus in order to keep nodes on the at least one selected bus in an awake state while allowing (a) node on at least one other bus to enter a power saving mode.

[0051] The control means 102 may comprise a control device 102 configured to provide network management, wherein the storage means 104 may comprise at least one storage device 104, and wherein the communication means 105 may comprise at least one transceiver 106 configured to communicate via a plurality of data buses. The transceiver 106 may be one of a plurality of transceivers 106, each configured to communicate via at least one data bus.

[0052] An apparatus 101 in which the present invention is embodied is shown in Fig. 1. The apparatus 101 comprises a control means 102 in the form of a control device 102. In the present embodiment, the control device 102 comprises a processor 103 and a storage device 104 for storing data, such as a lookup table 108, and program instructions 109 for causing the processor to function as described below. The program instructions may be provided via a non-transient computer-readable medium 110 containing the program instructions 109. The storage medium may comprise a storage device 104. The processor and the storage device may be formed as a single component or as separate components. Only one processor and only one storage device are shown in this example, but it should be understood that the control device may comprise multiple processors and multiple storage devices.

[0053] The device 101 further comprises a communication means 105 for transmitting and receiving signals via a plurality of data buses. The control means is configured to determine at least one selected bus with reference to at least one received request for partial network operation and, depending on the fulfillment of a set of conditions for partial network operation, to cause network management signals to be provided to the at least one selected bus in order to keep nodes on the at least one selected bus in an awake state while allowing at least one node on at least one other bus to enter a power-saving mode. The communication means may comprise one or more transceivers 106, each having at least one port 107 to be connected to a corresponding data bus.

[0054] The device 101 can be used as a central gateway (or gateway) in a vehicle. Like similar gateways known for use in a vehicle, the gateway 101 is configured to provide communication between the buses connected to it, so that nodes, such as ECUs (electronic control units), connected to one bus can communicate with nodes connected to another bus. The device 101 can be configured to provide communication between data buses of various types, such as those for use in a road vehicle, including a CAN (Controller Area Network) bus, a FlexRay bus, a LIN (Local Interconnect Network) bus, or an Ethernet bus.

[0055] In addition to providing communication between buses, the device 101, like existing gateways, is / are configured to control the waking up of nodes on the buses and to enable the nodes to power down (i.e., to allow the nodes to enter a low-power mode). When nodes are in a low-power mode, they turn off most of their processing functions to conserve power, while maintaining some processing logic in the physical logic in a wake state to monitor for the presence of communication over a bus to which they are connected.

[0056] If device 101 has enabled all connected nodes to be in a power-saving mode and receives a network management message from a node via transceiver 106 indicating that communication is required, it responds by sending a network management signal to each of the connected buses to wake up all connected buses. While continuing to receive network management messages indicating that communication is still required, device 101 is configured to provide network management signals to connected buses to keep all connected nodes awake.

[0057] Depending on the device 101 no longer receiving network management messages from nodes indicating that communication is required, the device 101 is configured to provide signals to connected buses to indicate to connected nodes that they may again enter a power saving mode.

[0058] Device 101 differs from conventional central gateways in that it is configured to receive requests for partial network operation and provide communication related to those requests. When device 101 receives a network management message and a request for partial network operation from the same node, it can allow some nodes (not required for the communication requested by the request for partial network operation) to return to power-saving mode while keeping selected buses required for partial network operation awake. In this way, device 101 can enable communication between nodes on different buses while simultaneously allowing nodes on buses not required for communication to enter a power-saving mode.

[0059] An electronic control unit (ECU) 201 for a vehicle is in Fig. 2. The electronic control unit comprises a control means 202 for controlling a system in a vehicle and a communication means 203 for communicating via a bus. The control means 202 may comprise a control device comprising at least one processor 204 and a memory means 205. The memory means 205 may comprise one or more memory devices 205 for storing data and / or program instructions executed by the processor 204 to perform its various functions. The communication means 203 may comprise one or more transceivers 206, each having one or more ports 207 for communicating via a data bus.In use, the electronic control unit (ECU) 201 has a port 207 connected via a data bus to a gateway, such as a device 101, so that the ECU 201 is able to communicate with other nodes connected to the device 101 via other buses.

[0060] Like other existing electronic control units, when the ECU 201 wakes up from a power saving mode and requires communication with one or more other nodes in a different network connected to it, it provides a network management message to the central gateway so that the central gateway wakes up all other nodes in the network to enable communication.However, the ECU 201 differs from existing electronic control units in that when it wakes up from a power saving mode and requires communication with one or more other nodes, it is configured to: determine that a first function to be performed is executable with partial network operation; and, contingent upon the first function to be performed being executable with partial network operation, communicate a request for network management to a gateway and communicate a request for partial network operation to the gateway.

[0061] An example of a network 301 in a vehicle 305 comprising the device 101 is shown schematically in Fig. 3. Like device 101, network 301 includes multiple data buses (such as buses 303) connected to corresponding ports 107 of device 101. Each of buses 303 further has one or more other nodes 302 connected thereto, and at least some of the nodes may include an electronic control unit (ECU) 201. In the present example, three of buses 303A, 303B, and 303C are CAN buses and are connected to ports 107 of a first transceiver 106A, while one bus 303D is a FlexRay bus and is connected to a port 107 of a second transceiver 106B.

[0062] When a node 302 on a bus 303 wakes up from a power-saving mode to perform a function that requires communication over the network 301, it may provide a network management message to the device 101 as previously discussed. However, for one or more functions that a node 302 is performing, the function may be performed with communication to specific other node(s), and the function may not require nodes on all buses to be awake. For such a function, a node 302 may request partial network operation by sending a partial network operation request to the device 101.The term "partial networking" refers to a state in which selected data buses are kept awake for communication over those buses, while allowing one or more other buses to enter a low-power mode. Similarly, a "partial networking request" is a message that provides a request for "partial networking."

[0063] A method 400 performed by a node 302, such as the ECU 201, requiring communication over a network, such as network 301, is described in Fig. 4. If a node is executing several different functions, some of which can be performed using partial networking and some of which require the entire network 301 to remain awake, the node first determines in block 401 whether the function to be executed can be performed using partial networking. This can be achieved by the node having a stored lookup table listing the functions to be executed by the node, as well as an indicator associated with each of these functions to be executed indicating whether or not partial networking can be employed.Accordingly, when a function to be executed is to be performed by a node, such as ECU 201, processor 204 accesses data stored in the lookup table in memory 205 and retrieves the indicator associated with the first function to be executed to determine whether partial network operation is possible with that function to be executed.

[0064] If it is determined that partial network operation is possible for the first function to be performed, then the ECU may request partial network operation from the gateway 101. This may be achieved by transmitting a network management message to the gateway 101 and transmitting a request for partial network operation to the gateway in block 402.

[0065] If it is determined that partial network operation is not available for the first function to be performed, then the ECU 201 may send a network management message to the gateway 101 in block 402 such that the gateway 101 wakes up all connected buses (i.e., all nodes in all connected buses) and keeps all buses awake so that communication from the requesting node can occur.

[0066] An ECU 201 may perform various functions that require only partial network operation, and the request for partial network operation may include a message identifying the function to be performed that requires communication to enable the gateway 101 to obtain the required buses in an awake state.

[0067] Some nodes 302, such as the ECU 201, may be configured to perform two or more different functions, where at least one function to be performed allows communication through partial networking and at least one function to be performed does not allow communication through partial networking (i.e., requires all buses to remain in a wake state). A method 500 performed by this node is described in Fig. 5. First, in block 501, it is determined whether all functions to be executed are executable with partial network operation. The process in block 501 may be performed by retrieving data from a lookup table to determine whether each function to be executed can be executed with partial network operation.

[0068] Depending on whether all functions to be executed are executable with partial network operation, one or more requests for partial network operation are transmitted in block 502, identifying each function to be executed for which partial network operation is requested. Depending on whether a function to be executed is not executable with partial network operation, a network management message without a request for partial network operation is transmitted in block 503 to require that all buses be kept awake.

[0069] In one embodiment, a request for partial networking comprises a partial networking signal comprising one or more flags, each indicating whether partial networking is required or not for a given function to be performed. In one embodiment, the flags are provided in the form of a respective predetermined bit corresponding to each function to be performed that is executable by partial networking. For example, if partial networking is to be performed with respect to a function to be performed, the predetermined bit is set to "1" to indicate that partial networking is requested with respect to a function to be performed, and is otherwise set to "0". Accordingly, a request for partial networking comprises a partial networking signal indicating that at least one function to be performed requires partial networking.Of course, in an alternative embodiment, a positive flag may be defined as a "0" instead of a "1", while a negative flag indicating that the function to be performed is not required may be defined as a "1" instead of a "0".

[0070] In one example, the electronic control unit (ECU) 201 may be an engine control unit or a powertrain control unit, and the first function to be performed may include communication related to battery charging. For this function to be performed, communication may be safely generated using partial networking and by allowing the gateway 101 to allow buses not required for communication to enter a power-saving mode. A second function to be performed by such an engine control unit may be to provide periodic transmission of engine data to a communication node for further transmission of the data. This function to be performed may also be safely performed using partial networking.Accordingly, if both of these functions are to be performed, the engine control unit may transmit a network management message followed by one or more requests for partial network operation that identify these two functions to be performed for the gateway.

[0071] However, such an engine control unit would also require communication while the engine is running. The function to be performed while the engine is running requires that all buses remain awake for safety reasons. Therefore, this is an example of a function to be performed that cannot be performed with partial network operation. Therefore, while the engine is running, regardless of whether other functions that are executable with partial network operation are to be performed, the engine control unit transmits a network management message to the gateway 101 without a request for partial network operation, causing the gateway to remain awake.

[0072] A network management message sent by a node 302 includes an identifier that identifies the node to the gateway 101. Similarly, a request for partial network operation sent by a node 302 includes an identifier that identifies the node to the gateway 101. Accordingly, the node provides information that allows the gateway 101 to correlate received network management messages and requests for partial network operation.

[0073] A method 600 that can be performed by the device (or gateway) 101 is shown in the flowchart in Fig. 6. In response to receiving a request for partial network operation, at least one selected bus is determined with respect to the request for partial network operation in block 601.

[0074] In one example where nodes may perform multiple different functions to be performed, enabling partial network operation, the request for partial network operation identifies the function to be performed. The at least one selected bus may be determined by looking up the function to be performed in a lookup table (e.g., lookup table 108 stored in memory 104 of device 101) to determine the selected buses associated with that function to be performed. (An example of a lookup table is shown in Fig. 11, in which a first node "NODE #1" is capable of executing three functions "FUNCTION #1", "FUNCTION #2", and "FUNCTION #3", which can be executed through partial networking. A second node "NODE #2" is capable of executing one function "FUNCTION #4" with partial networking. "FUNCTION #1" requires that the buses "BUS #1" and "BUS #2" be awake, while the other functions only require that either "BUS #1" or "BUS #2" be awake.)

[0075] In an alternative example, where nodes may only perform a single function requiring partial networking, the request for partial networking may identify the node that sent the request, and the at least one bus may be determined by looking up the identity of the node in a lookup table to retrieve selected buses associated with a request from the node.

[0076] At block 602, it is determined whether a set of partial network operation conditions is met. In one example, the set of partial network operation conditions includes a condition, and the condition is that the vehicle ignition switch is in an "off state" rather than an "on state." This means the engine is not running or starting, and no user inputs have been received indicating that the vehicle should be driven. These user inputs include, for example, pressing a starter button without applying the brake pedal.

[0077] Depending on the fulfillment of the set of conditions for partial network operation in block 602, a network management signal (or "NM" signal) is provided to the at least one selected bus to maintain nodes on the at least one selected bus in an awake state, while at least one node on at least one other bus is allowed to enter a power-saving mode in block 603. For example, the device 101 may provide network management signals to one or more connected data buses (such as buses 303 in Fig. 3) to keep connected nodes (such as node 302) in an awake state, and it may allow other connected buses (i.e., nodes on other connected buses) to enter a power-saving mode by no longer providing network management signals to those buses.

[0078] If it is determined in block 602 that the set of conditions for partial network operation is not met, then nodes on all connected buses are maintained in an awake state in block 604. For example, the set of conditions for partial network operation includes the condition that the vehicle ignition switch is in an "off" state, and if the ignition switch is in an "on" state, the condition is not met.

[0079] It should be noted that the operation in block 602 may be completed before the operation in block 601; in this case, block 601 is only executed if it is determined in block 602 that the conditions for partial network operation are met.

[0080] The set of partial network operation conditions to be satisfied in block 602 may include multiple partial network operation conditions, and an exemplary method for determining whether all partial network operation conditions are satisfied is described in Fig. 7. In this example, five partial networking conditions must be met for partial networking to be enabled. In block 701, it is determined whether the partial networking request (or "PN request") originates from the same source as the received network management message (or "NM message"). Otherwise, it is possible that the partial networking request was received in error, and partial networking will not be enabled because not all partial networking conditions (or "PN conditions") are met. This means that the first condition to be met is that the request originates from the same source as a received network management message.To determine the source of the partial networking request, the partial networking request itself may contain an identifier that identifies the node that submitted the request.

[0081] Alternatively, if partial networking is requested by only one node for each function to be performed for which partial networking can be enabled, the gateway may have a lookup table indicating which node is configured to submit a request for partial networking for each function to be performed. In this case, the request for partial networking may include a function identifier that identifies the function to be performed, and the lookup table may be used to retrieve the identity of the node that submitted the request for partial networking.

[0082] In block 702, it is determined whether partial networking is disabled, for example, by manual input into the gateway by a technician. The partial networking condition to be met in block 702 is that partial networking is not disabled. Similarly, in block 703, it is determined whether partial networking is disabled for the partial networking function to be performed (“PN function”) identified by the partial networking request. The partial networking condition to be met in block 703 is that partial networking is not disabled with respect to this function to be performed.

[0083] In block 704, it is determined whether the vehicle ignition switch is in the on state. If so, partial network operation is not enabled. Thus, the condition for partial network operation is that the vehicle ignition switch is in the off state.

[0084] In block 705, it is determined whether all buses must be kept awake for at least a minimum duration, and if so, partial network operation may be enabled. The minimum duration is typically 5 seconds. Accordingly, the condition for partial network operation to be met in block 705 is that all buses must be kept awake for at least a minimum duration. Note that in other examples, the number of conditions to be met for partial network operation may be fewer than the five provided in this example, or additional conditions for partial network operation may be included.

[0085] Another exemplary method 800 executable by the device (or gateway) 101 is shown in the flowchart of Fig. 8. Method 800 is performed when device (or gateway) 101 has enabled nodes on connected buses to enter a power-saving mode, but network communication is required. In block 801, network management signals are provided to all buses connected to device 101 to indicate that all nodes on the connected buses are to be placed in an awake state.

[0086] In block 802, it is then determined who / what is requesting network communication. If it is determined in block 802 that nothing / nobody is requesting network communication, the process in blocks 801 and 802 is repeated.

[0087] If it is determined at block 802 that a normal function to be performed (i.e., one that does not enable partial network operation) requires network communication, then at block 801, all buses are kept awake, and the process returns to block 802. An indication that network communication is required for a normal function to be performed would be receiving a network management message from a node without a request for partial network operation from the same node. It may be noted that if a request for network communication for a non-partial network function (a "normal function") is received, all buses are kept awake at block 801, even if a request for partial network operation is received from another node.

[0088] Alternatively, if it is determined in block 802 that one or more requests for network communication have been received with respect to a function to be performed for which partial network operation is possible, but no requests have been received with respect to non-partial network functions, block 803 is executed. This means that if it is determined in block 802 that one or more requests for partial network operation have been received, block 803 is executed, in which it is determined whether a set of conditions for partial network operation is met. The conditions for partial network operation may include some or all of the conditions previously described with respect to Fig. 7. If not all of the partial network operation conditions in the set are met, the process returns to block 801, where all buses are kept awake until block 802 is repeated.

[0089] Alternatively, if it is determined in block 803 that all required conditions for partial networking are met, at least one selected bus related to the function or functions to be performed is determined in block 804 for which requests for partial networking have been received. This means that one or more selected buses are identified as those required to provide communication related to the received request(s) for partial networking. Only those buses required to provide communication for partial networking for the function to be performed are kept awake in block 805, while one or more other buses are allowed to enter a power-saving mode.This means that network management signals are provided only to selected buses that are required to provide communication between nodes on those buses for the function or functions of the partial network operation to be performed. The network management signals are not provided to the other buses, allowing the nodes on those other buses to enter a power-saving mode.

[0090] An example of the process in block 804 is described in more detail in Fig. 9. In block 901, for each function to be performed received from the partial networking request(s), a lookup table (e.g., lookup table 108 stored in memory 104 of device 101) is accessed to retrieve a set of bus identifiers corresponding to that function to be performed. If it is determined in block 902 that communication is required for more than one partial networking function to be performed, a logical "OR" function may be performed on the sets of buses in block 903 to determine the selected buses.

[0091] For example, it may be determined that a first set of selected buses is required to provide the requested partial network operation for a request for partial network operation; and that a second set of selected buses is required to provide partial network operation for a second request for partial network operation. A logical OR function is then performed on the first set and the second set to determine the at least one selected bus to which network management signals are provided to keep these buses in an awake state. For example, if the first set includes buses 303A and 303C (in Fig. 3) and the second set includes bus 303A and 303D, then the logical OR would result in buses 303A, 303C, and 303D being kept awake while allowing bus 303B to enter a power saving mode.

[0092] Another exemplary method 1000 executable by the device (or gateway) 101 is shown in the flowchart of Fig. 10. As previously mentioned, the device 101 is configured to provide network management signals to connected data buses (such as buses 303 in Fig. 3) to keep connected nodes (such as nodes 302) in a wake-up state. It is further configured to allow connected buses (i.e., nodes on connected buses) to enter a power-saving mode when the wake-up state is not required, such as in block 1001 of Fig. 10. While allowing the nodes to enter a power saving mode in block 1001, the device 101 may continuously or repeatedly determine whether a portion of the network 301 requests network communication in block 1002. This request may originate from a module in the device 101 itself or the device may be provided to the device 101 when a network management message from a node (such as a node 302 of Fig. 3) is received via a bus (such as bus 303).

[0093] If it is determined in block 1002 that there is a request for network communication, a timer is started from zero in block 1003 and in block 1004 network management signals are provided to all buses connected to device 101 to indicate that nodes on the connected buses are to be put into an awake state.

[0094] In block 1005, it is then determined what is requesting network communication. If it is determined that nothing / nobody is requesting network communication, in block 1006 it is determined whether the timer has been running for at least a predetermined minimum period of time (typically five seconds). If not, block 1004 is executed again to keep the buses awake. Then, in block 1005, it is again determined who / what is requesting the network. Blocks 1006, 1004, and 1005 are repeated several times if nothing / nobody is requesting the network, until it is determined in block 1006 that the timer has run for at least the predetermined period of time. At this time, all buses are released in block 1007. This means that network management signals previously provided to all buses are stopped in block 1007 to allow all connected nodes to enter a power-saving mode.The process then returns to block 1001 and block 1002 to await further network requests.

[0095] Alternatively, if it is determined at block 1005 that a normal function to be performed, i.e., one that does not enable partial network operation, requires network communication, then at block 1004, all buses are kept awake, and the process returns to block 1005. An indication that network communication is required for a normal function to be performed would be receiving a network management message from a node without a request for partial network operation from the same node. It may be noted that even if a request for partial network operation is received from another node, if a request for network communication for a non-partial network function (a "normal function") is received, all buses are kept awake at block 1004.

[0096] Alternatively, if it is determined in block 1005 that the only request(s) for network communication has / have been received relating to a function to be performed for which partial network operation is possible, block 1008 is executed. That is, if it is determined in block 1005 that one or more requests for network communication have been received, but that all relate to functions to be performed for which partial network operation is possible, then block 1008 is executed. In block 1008, it is determined whether a set of conditions for partial network operation is met. The conditions for partial network operation may include some or all of the conditions previously described with respect to Fig. 7. If not all of the partial network operation conditions are met, the process returns to block 1004, where all buses are kept awake until block 1005 is repeated.

[0097] Alternatively, if it is determined in block 1008 that all the required partial networking conditions are met, in block 1009 at least one selected bus is determined with respect to the partial networking function or functions to be performed for which partial networking requests have been received. The process in block 1009 may be the same as that previously described with respect to Fig. 9 described process in block 804.

[0098] Only those buses required to provide communication to partial network operation for the function to be performed are kept awake in block 1010, while one or more other buses are allowed to enter a power-saving mode. This means that network management signals are provided only to the selected buses required to provide communication between nodes on those buses for the function or functions of partial network operation to be performed. Signals are provided to the remaining buses to allow nodes on those buses to enter a power-saving mode.

[0099] In block 1011, it is determined whether there have been any changes to the status of requests for network communication; otherwise, block 1008 is repeated. A change may be due to the receipt of a new network management message relating to a new request for communication over the network (with or without a request for partial network operation). Alternatively, the change may be an indication from a node that communication over the network is no longer required for a particular function to be performed. In either case, if it is determined in block 1011 that there has been a change in the request status, the process returns to block 1003 where the timer is reset before network management signals are provided to all buses to place the connected nodes into an awake state in block 1004.Accordingly, each time a new request is received or when a function requiring partial network operation is completed, all buses are placed in a wake state. The process then returns to block 1005.

[0100] If no longer executable functions are being performed that require communication over the network, then the process bypasses blocks 1006, 1004, and 1005 until the timer exceeds the specified minimum period and the buses are allowed to enter power saving mode in block 1007.

[0101] For the purposes of this disclosure, it is understood that the control unit(s), ECU(s), and gateway(s) described herein may each comprise a control unit or a computing device having one or more electronic processors. Accordingly, a vehicle and / or system may comprise a single control unit or electronic control unit; alternatively, different functions to be performed by the control unit(s) may be embodied or incorporated into different control units or control devices. A set of instructions may be provided which, when executed, causes the control unit(s) or control unit(s) to perform the control techniques described herein (including the method(s) described).The set of instructions may be incorporated into one or more electronic processors; alternatively, the set of instructions may be provided as software on the computing device that is executed by one or more electronic processors. For example, a first controller may be implemented in software that is executed on one or more electronic processors, and one or more further controllers may also be implemented in software that is executed on one or more electronic processors, optionally the same one or more electronic processors as the first controller. However, it should be understood that other arrangements are also suitable and that, accordingly, the present disclosure should not be limited to any particular arrangement. In any event, the above-described set of instructions may be embodied in a computer-readable storage medium (e.g.,a non-transient storage medium) that includes a mechanism for storing information in a form readable by a machine or electronic processor / computing device, including, but not limited to: magnetic storage medium (e.g., a floppy disk); optical storage medium (e.g., CD-ROM); magneto-optical storage medium; read-only memory (ROM); random access memory (RAM); rewritable programmable memory (e.g., EEPROM and EEPROM); flash memory; or electronic and other types of media to store this information / instructions.

[0102] The Fig.The blocks illustrated in Figures 4 to 10 may represent steps in a method and / or sections of code in the computer program 109. The illustration of a particular order for the blocks does not necessarily imply a required or preferred order for the blocks, and the order and arrangement of the blocks may be varied. Furthermore, some of the steps may be omitted.

[0103] It should be noted that although embodiments of the invention have been described in the preceding sections with reference to various examples, changes may be made to the given examples without departing from the claimed scope of the invention.

[0104] Features described in the above description may be used in combinations other than those expressly described.

[0105] Although functions to be performed have been described with reference to certain features, these functions to be performed can also be performed by other features, whether so described or not.

[0106] Although features have been described with reference to particular embodiments, these features may also be present in other embodiments, whether described or not.

[0107] Although an attempt has been made in the above specification to emphasize those features of the invention which are of particular importance, it is to be understood that the applicant seeks protection with respect to any patentable feature or combination of features referred to above and / or shown in the drawings, whether or not specifically emphasized.

Claims

[1] A device (101) for providing communication between buses (303, 303A, 303B, 303C, 303D) in a vehicle (305), the device (101) comprising control means (102, 202), storage means (104, 205) for storing data, and communication means (105, 203) for transmitting and receiving signals via a plurality of data buses, the device (101) being further configured to: Receiving a request for partial network operation; Selecting at least one of a plurality of buses (303, 303A, 303B, 303C, 303D) based on a received request for partial network operation; and depending on the satisfaction of a set of conditions (701-705) for partial network operation, causing network management signals to be provided to the at least one selected bus (303, 303A, 303B, 303C, 303D) to maintain nodes (302) on the at least one selected bus (303, 303A, 303B, 303C, 303D) in an awake state while allowing (a) node (302) on at least one other bus to enter a power saving mode. [2] The device (101) of claim 1, wherein the control means (102, 202) is configured to: Determining whether a network management message has been received without a request for partial network operation; and responsive to receiving a network management message without a request for partial network operation, causing network management signals to be provided to maintain (a) node (302) on all connected buses (303, 303A, 303B, 303C, 303D) in an awake state. [3] The device (101) of claim 1 or 2, wherein the control means (102, 202) is configured to: Selecting a set of buses (303, 303A, 303B, 303C, 303D) from a plurality of data buses required to provide partial networking for each of a plurality of partial networking requests; and Performing a logical OR function on the sets of selected buses (303, 303A, 303B, 303C, 303D) to determine the at least one selected bus (303, 303A, 303B, 303C, 303D). [4] The device (101) according to any one of claims 1 to 3, wherein the set of conditions (701-705) comprises a plurality of conditions (701-705) and the control means (102, 202) is configured to determine whether all conditions (701-705) are met. [5] The apparatus (101) of any one of claims 1 to 4, wherein the set of conditions (701-705) for partial networking is independent of a current request for networking without partial networking. [6] The apparatus (101) of any one of claims 1 to 5, wherein the set of conditions (701-705) for partial network operation includes a vehicle ignition switch being in an off state. [7] The apparatus (101) of any one of claims 1 to 6, wherein the control means (102, 202) is configured to determine whether a request for partial network operation received from a node (302) is valid by determining whether a network management message has also been received from the same node (302). [8] Device (101) according to one of claims 1 to 7, wherein the control means (102, 202) is configured to: Providing network management signals for maintaining nodes (302) in the at least one selected bus (303, 303A, 303B, 303C, 303D) and in the at least one other bus in an awake state for a predetermined period of time; and thereafter, enabling (a) node (302) in the at least one other bus to enter a power saving mode while simultaneously providing network management signals to the at least one selected bus (303, 303A, 303B, 303C, 303D) for maintaining nodes (302) in the at least one selected bus (303, 303A, 303B, 303C, 303D) in an awake state. [9] The apparatus (101) of any one of claims 1 to 8, wherein the control means (102, 202) is configured to: receive a request for partial network operation identifying a function to be performed; and determine the at least one selected bus (303, 303A, 303B, 303C, 303D) by retrieving at least one bus identifier corresponding to the function to be performed from the storage means (104, 205). [10] Device (101) according to one of claims 1 to 8, wherein the control means (102, 202) is configured to: Receiving a first request for partial network operation defining a first function to be performed and a second request for partial network operation defining a second function to be performed; Retrieving at least one first bus identifier corresponding to the first function to be performed and retrieving at least one second bus identifier corresponding to the second function to be performed; and Performing a logical OR function on the first and second bus identifiers to determine the at least one selected bus (303, 303A, 303B, 303C, 303D) for the requested partial network operation. [11] Device (101) according to one of claims 1 to 10, wherein the control means (102, 202) is configured to: Monitoring changes in the status of network operation requirements; and depending on a change in the status of requests for network operation, providing network management signals to all buses to place nodes (302) into an awake state. [12] Device (101) according to one of claims 1 to 11, wherein the device (101) comprises a central gateway. [13] An electronic control unit (201) for a vehicle (305), the electronic control unit comprising: a control means (102, 202) for controlling a system in a vehicle (305) and a communication means (105, 203) for communicating via a bus (303, 303A, 303B, 303C, 303D), the electronic control unit (201) being configured to: Determining that a first function to be executed is executable with partial network operation; subject to the first function to be performed being executable with partial networking, transmitting a network management message and transmitting a request for partial networking. [14] The electronic control unit (201) of claim 13, wherein the request for partial network operation comprises a message identifying the first function to be performed. [15] Electronic control unit (201) according to claim 13 or 14, wherein the electronic control unit (201) is configured to: Determining whether both the first function to be executed and the second function to be executed are executable with partial network operation; and subject to both the first function to be performed and the second function to be performed being executable with partial networking, transmitting one or more requests for partial networking identifying the first function to be performed and the second function to be performed. [16] Electronic control unit (201) according to one of claims 13 to 15, wherein the electronic control unit (201) is configured to: Determining that a further function to be performed is not executable with partial network operation; and depending on the further function to be performed not being executable with partial network operation, transmitting a network management message without a request for partial network operation to require that all buses be kept in an awake state. [17] Electronic control unit (201) according to one of claims 13 to 16, wherein the electronic control unit (201) is an engine control unit or a powertrain control unit and the first function to be performed comprises communication related to battery charging. [18] A communication network for a vehicle (305), the communication network comprising a device (101) according to any one of claims 1 to 12, which is operatively connected to a plurality of nodes (302) via a plurality of buses. [19] Vehicle (305) having the communication network according to claim 18. [20] A non-transient computer-readable medium comprising a set of computer instructions that, when executed by a processor, cause the execution of selecting at least one of a plurality of buses (303, 303A, 303B, 303C, 303D) based on a received request for partial network operation; and contingent upon satisfaction of a set of partial network operation conditions (701-705), causing network management signals to be provided to the at least one selected bus (303, 303A, 303B, 303C, 303D) to maintain nodes (302) on the at least one selected bus (303, 303A, 303B, 303C, 303D) in an awake state while allowing (a) node (302) on at least one other bus to enter a power-saving mode.

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