Patent Description:
A conveying line product is generally used for back-end logistics sorting and outbound delivery of modern logistics merchants. A conveying line is an aggregation of all conveying devices for completing article conveying, such as a conveying belt and a conveyor. A site surrounding a warehouse, a production workshop, and a packaging workshop is provided with conveying chains that are formed by many belt conveyors, roller conveyors, and the like. These conveying chains are connected end to end to form a continuous conveying line. Because the conveying line not only requires a physical device used for actual conveying, but also requires an electric control signal for controlling conveying of the conveying line, control components and a control bus are further required in the conveying line. The control components are distributed to parts of the conveying line, and interaction of the electric control signal is performed through the uniform control bus.

Because the conveying line includes many devices, and various line connections of the control components and the control bus are complex, an on-site engineer needs to perform a large quantity of debugging on signal point positions and collaboration relationships. In addition, actual site forms of all stores have a tremendous difference. As a result, the construction process cannot be standardized, and the debugging process is very long. In the existing technology, the <NUM> serial port communication technology or the RJ45 Ethernet technology is mainly adopted to standardize the electric control part in a conveying line. The time delay of the <NUM> serial port communication is relatively large. The time delay is controlled in the RJ45 Ethernet. However, because each device is connected to a same network switch device, the network wiring and device management costs are relatively high. Currently, there is a lack of a technology that can standardize the electric control part used in the conveying line and give consideration to both the time delay and costs of the network wiring and device management, as can be seen in document <CIT>.

In view of this, the present disclosure aims to provide a technology for standardizing an electric control part used in a conveying line, to reduce a time delay and costs of network wiring and device management according to independent claims <NUM> and <NUM> and to dependent claims <NUM>-<NUM> and <NUM>-<NUM>.

Optionally, the routing CAN bus network access unit or the internal CAN bus network access unit further comprises: a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit.

Optionally, the internal CAN bus network access unit of the first CAN comprises a message sending CAN bus network access unit and a message receiving CAN bus network access unit, wherein the first CAN bus transceiver of the message sending CAN bus network access unit is configured to broadcast a directing message to another CAN bus network access unit in the first CAN, and the directing message contains an identifier of the message receiving CAN bus network access unit; the message receiving CAN bus network access unit is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message matches its own identifier, and to reserve the directing message; and another internal CAN bus network access unit other than the message receiving CAN bus network access unit is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message does not match its own identifier, and to discard the directing message; and the routing CAN bus network access unit is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message is in a first CAN bus network access unit identifier list, and to discard the directing message.

Optionally, the internal CAN bus network access unit of the first CAN comprises a message sending CAN bus network access unit, and the internal CAN bus network access unit of the second CAN comprises a message receiving CAN bus network access unit, wherein the first CAN bus transceiver of the message sending CAN bus network access unit is configured to broadcast a directing message to another CAN bus network access unit in the first CAN, and the directing message contains an identifier of the message receiving CAN bus network access unit; another internal CAN bus network access unit is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message does not match its own identifier, and to discard the directing message; the routing CAN bus network access unit is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message is not in a first CAN bus network access unit identifier list, and to broadcast the directing message to the internal CAN bus network access unit in the second CAN through the second CAN bus transceiver; and the message receiving CAN bus network access unit in the second CAN is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message matches its own identifier, and to reserve the directing message; and another internal CAN bus network access unit other than the message receiving CAN bus network access unit in the second CAN is configured to, after receiving the directing message, determine that the identifier of the message receiving CAN bus network access unit contained in the directing message does not match its own identifier, and to discard the directing message.

Optionally, the electric control network is an electric control network in a logistics conveying line, and at least one of the first port and the plurality of variable connection ports is connected to a control component configured to control logistics conveying in the logistics conveying line.

Optionally, the electric control network is an electric control network in a product production line, and at least one of the first port and the plurality of variable connection ports is connected to a control component configured to control product production in the product production line.

Optionally, the electric control network is an Internet of Things, and at least one of the first port and the plurality of variable connection ports is connected to an Internet of Things device accessing the Internet of Things.

According to some embodiments of the present disclosure, a status notification method for a CAN bus network access unit is provided, wherein the CAN bus network access unit comprises: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port; the CAN bus network access unit is classified into a straight-line CAN bus network access unit and a transplanter CAN bus network access unit, wherein the third port of the straight-line CAN bus network access unit is connected to the second CAN bus, and any one of the second port and the fourth port is connected to neither the first CAN bus nor the second CAN bus; and any one of the second port, the third port, and the fourth port of the transplanter CAN bus network access unit is connectable to the first CAN bus or the second CAN bus; and the method comprises: determining whether the CAN bus network access unit is the straight-line CAN bus network access unit or the transplanter CAN bus network access unit; if the CAN bus network access unit is the straight-line CAN bus network access unit, connecting the first port to the first CAN bus and the third port to the second CAN bus in a first scanning period, a second scanning period, a third scanning period, and a fourth scanning period that are consecutive; if the CAN bus network access unit is the transplanter CAN bus network access unit, connecting the first port to the first CAN bus and the second port, the third port, and the fourth port to the second CAN bus in the first scanning period; connecting the first port, the third port, and the fourth port to the first CAN bus and the second port to the second CAN bus in the second scanning period; connecting the first port, the second port, and the fourth port to the first CAN bus and the third port to the second CAN bus in the third scanning period; and connecting the first port, the second port, and the third port to the first CAN bus and the fourth port to the second CAN bus in the fourth scanning period; and sending messages by using the first CAN bus transceiver and the second CAN bus transceiver and notifying, through ports connected to the first CAN bus transceiver and the second CAN bus transceiver, an identifier of the CAN bus network access unit, a bus number corresponding to the transceivers, and a port number of a port connected to the bus.

Optionally, before the connecting the first port to the first CAN bus and connecting the third port to the second CAN bus in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period that are consecutive, the method further comprises: connecting the first port to the first CAN bus and connecting the third port to the second CAN bus in a first silent period before the first scanning period; and after the connecting the first port to the first CAN bus and connecting the third port to the second CAN bus in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period that are consecutive, the method further comprises: connecting the first port to the first CAN bus and connecting the third port to the second CAN bus in a second silent period before the fourth scanning period.

Optionally, before the connecting the first port to the first CAN bus and connecting the second port, the third port, and the fourth port to the second CAN bus in the first scanning period, the method further comprises: connecting the first port to the first CAN bus and connecting the second port, the third port, and the fourth port to the second CAN bus in a first silent period before the first scanning period; and after the connecting the first port, the second port, and the third port to the first CAN bus and connecting the fourth port to the second CAN bus in the fourth scanning period, the method further comprises: connecting the first port, the second port, and the third port to the first CAN bus and connecting the fourth port to the second CAN bus in a second silent period after the fourth scanning period.

Optionally, before the determining whether the CAN bus network access unit is the straight-line CAN bus network access unit or the transplanter CAN bus network access unit, the method further comprises: receiving a CAN control message in a scanning starting subtype sent by a detection starting CAN bus network access unit.

Optionally, the CAN control message in the scanning starting subtype is broadcasted by the detection starting CAN bus network access unit in a CAN in which the detection starting CAN bus network access unit is located; and is broadcasted by a routing CAN bus network access unit between the CAN and another CAN to a CAN bus network access unit in the another CAN.

Optionally, the sending messages by using the first CAN bus transceiver and the second CAN bus transceiver and notifying, through ports connected to the first CAN bus transceiver and the second CAN bus transceiver, the identifier of the CAN bus network access unit, the bus number corresponding to the transceivers, and the port number of the port connected to the bus comprises: for the straight-line CAN bus network access unit, sending a message by using the first CAN bus transceiver and notifying, through the first port connected to the first CAN bus transceiver, the identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>; and sending a message by using the second CAN bus transceiver and notifying, through the third port connected to the second CAN bus transceiver, the identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>; and for the transplanter CAN bus network access unit, sending a message by using the first CAN bus transceiver, notifying, through a port connected to the first CAN bus transceiver, the identifier of the CAN bus network access unit, a bus number <NUM>, and a particular flag bit, and responding, in response to receiving a port query request, with a port number the first CAN bus connected to; and sending a message by using the second CAN bus transceiver, notifying, through a port connected to the second CAN bus transceiver, the identifier of the CAN bus network access unit, a bus number <NUM>, and a particular flag bit, and responding, in response to receiving a port query request, with a port number of a port connected to the first CAN bus.

According to some embodiments of the present disclosure, a connection status detection method for a CAN bus network access unit is provided, wherein the CAN bus network access unit comprises: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port; the CAN bus network access unit is classified into a straight-line CAN bus network access unit and a transplanter CAN bus network access unit, wherein the third port of the straight-line CAN bus network access unit is connected to the second CAN bus, and any one of the second port and the fourth port is connected to neither the first CAN bus nor the second CAN bus; and any one of the second port, the third port, and the fourth port of the transplanter CAN bus network access unit is connectable to the first CAN bus or the second CAN bus; and the method comprises: determining, for a to-be-detected port of the CAN bus network access unit if the to-be-detected port receives, in a first scanning period, a second scanning period, a third scanning period, and a fourth scanning period that are consecutive, a message notifying an identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>, that the to-be-detected port is connected to a straight-line CAN bus network access unit, and recording the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a first port of the straight-line CAN bus network access unit, and the first port is a logical entry; determining, if the to-be-detected port receives, in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period that are consecutive, a message notifying a notification of the identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>, that the to-be-detected port is connected to a straight-line CAN bus network access unit, and recording the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a third port of the straight-line CAN bus network access unit, and the third port is a logical exit; determining, if the to-be-detected port receives, in the first scanning period, a message notifying the identifier of the CAN bus network access unit, a bus number <NUM>, and a particular flag bit, that the to-be-detected port is connected to a transplanter CAN bus network access unit, and recording the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a first port of the straight-line CAN bus network access unit, and the first port is a logical entry; recording, if the to-be-detected port receives, in the second scanning period, a message notifying the identifier of the CAN bus network access unit, a bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a second port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the second port is a logical exit; and in a case of the bus number <NUM>, the second port is a logical entry; recording, if the to-be-detected port receives, in the third scanning period, a message notifying the identifier of the CAN bus network access unit, a bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a third port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the third port is a logical exit; and in a case of the bus number <NUM>, the third port is a logical entry; and recording, if the to-be-detected port receives, in the fourth scanning period, a message notifying the identifier of the CAN bus network access unit, a bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a fourth port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the fourth port is a logical exit; and in a case of the bus number <NUM>, the fourth port is a logical entry.

Optionally, after the step of recording, if the to-be-detected port receives, in the fourth scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and the particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit, wherein the to-be-detected port is connected to a fourth port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the fourth port is a logical exit; and in a case of the bus number <NUM>, the fourth port is a logical entry, the method further comprises: generating, for each to-be-detected port of each CAN bus network access unit in an electric control network, a port connection diagram of the electric control network according to a recorded identifier of the connected CAN bus network access unit, a port number of the connected CAN bus network access unit, and whether the connected port is a logical entry or a logical exit.

According to some embodiments of the present disclosure, a status notification apparatus for a CAN bus network access unit is provided, wherein the CAN bus network access unit comprises: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port; the CAN bus network access unit is classified into a straight-line CAN bus network access unit and a transplanter CAN bus network access unit, wherein the third port of the straight-line CAN bus network access unit is connected to the second CAN bus, and any one of the second port and the fourth port is connected to neither the first CAN bus nor the second CAN bus; and any one of the second port, the third port, and the fourth port of the transplanter CAN bus network access unit is connectable to the first CAN bus or the second CAN bus; and the status notification apparatus comprises: a type determining module, configured to determine whether the CAN bus network access unit is the straight-line CAN bus network access unit or the transplanter CAN bus network access unit; a first connection setting module, configured to connect, if the CAN bus network access unit is the straight-line CAN bus network access unit, the first port to the first CAN bus and the third port to the second CAN bus in a first scanning period, a second scanning period, a third scanning period, and a fourth scanning period that are consecutive; a second connection setting module, configured to connect, if the CAN bus network access unit is the transplanter CAN bus network access unit, the first port to the first CAN bus and the second port, the third port, and the fourth port to the second CAN bus in the first scanning period; to connect the first port, the third port, and the fourth port to the first CAN bus and the second port to the second CAN bus in the second scanning period; to connect the first port, the second port, and the fourth port to the first CAN bus and the third port to the second CAN bus in the third scanning period; and to connect the first port, the second port, and the third port to the first CAN bus and the fourth port to the second CAN bus in the fourth scanning period; and a status notification module, configured to send messages by using the first CAN bus transceiver and the second CAN bus transceiver and notify, through ports connected to the first CAN bus transceiver and the second CAN bus transceiver, an identifier of the CAN bus network access unit, a bus number corresponding to the transceivers, and a port number of a port connected to the bus.

According to some embodiments of the present disclosure, a connection status detection apparatus for a CAN bus network access unit is provided, wherein the CAN bus network access unit comprises: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port;.

According to some embodiments of the present disclosure, a CAN bus network access unit is provided, including: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; a second port, a third port, and a fourth port; a memory; and a processing logic, wherein.

According to some embodiments of the present disclosure, a computer-readable medium is provided, storing control instructions, configured to be executed by a processing logic of a CAN bus network access unit, where in addition to the processing logic, the CAN bus network access unit further includes: a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port;.

According to some embodiments of the present disclosure, a computer-readable medium is provided, storing control instructions, configured to be executed by a processing logic of a CAN bus network access unit, where in addition to the processing logic, the CAN bus network access unit further includes a first CAN bus and a second CAN bus; a first CAN bus transceiver and a second CAN bus transceiver, respectively connected to the first CAN bus and the second CAN bus and respectively configured to communicate with another first CAN bus and another second CAN bus in another CAN bus network access unit; a first port, connected to the first CAN bus; and a second port, a third port, and a fourth port;.

Embodiments and various aspects of the present disclosure are illustrated in the following detailed description and the accompanying figures. Various features shown in the figures are not drawn to scale.

The following describes this disclosure based on the embodiments, but this disclosure is not merely limited to the embodiments. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the invention. Instead, they are merely examples of apparatuses and methods consistent with aspects related to the invention as recited in the appended claims. Particular aspects of the present disclosure are described in greater detail below. A person skilled in the art may also fully understand this disclosure without the descriptions of the details. To prevent the essence of this disclosure from being confused, well-known methods, procedures, and processes are not described in detail.

A conveying line product is generally used for back-end logistics sorting and outbound delivery of modern logistics merchants. A conveying line is a system formed by connecting various belt conveyors, roller conveyors, and the like. These belt conveyors, roller conveyors, and the like are arranged end to end in a site surrounding a warehouse, a production workshop, and a packaging workshop. The conveying line includes a physical part and a control part. The physical part includes physical devices such as belt conveyors and roller conveyors in the conveying line. To control these physical devices to operate normally, scattered control components for controlling these parts to operate need to be distributed on the conveying line. These control components are connected to each other and communicate with each other through control buses, to form the control part. Because the conveying line includes many devices, and various line connections of the control components and the control bus are complex, an on-site engineer needs to perform a large quantity of debugging on signal point positions and collaboration relationships. In addition, there are tremendous differences between actual site forms of each store. As a result, the construction process cannot be standardized.

In the existing technology, the <NUM> serial port communication technology or the RJ45 Ethernet technology is mainly adopted to standardize the electric control part in a conveying line.

In the <NUM> serial port communication, all communication devices need to be connected in series in a network, and interact with each other in a host polling manner. When the scale of the physical network is expanded, because communication between each device and a host needs to cost time, polling of the host from a first device to a last device costs a great deal of time. Therefore, the method has a natural disadvantage. Only after being polled, each device can communicate with the host. As a result, the real-time performance is challenged, and a different communication priority cannot be planned for each device. When the scale is expanded to a specific extent, the time delay of the communication is totally unacceptable.

When the RJ45 Ethernet is used for performing communication, each device is connected to a same network switch device. Theoretically, compared with the <NUM> serial port communication, the time delay of the processing is controlled. However, a single network switch device is very high in cost, and the costs of the network wiring and device management will be greatly increased when there are more than thousands of nodes.

In the embodiments of the present disclosure, the conveying line is divided into sections of conveying line regions. In each conveying line region, the control component(s) in the conveying line region control various operations in the region. An electric control part is realized in the form of a plurality of CANs connected in series. In each CAN, there are a plurality of CAN bus network access units. Each CAN bus network access unit corresponds to a conveying line region, and is connected to the control component(s) in the conveying line region. In this way, the conveying line and the electric control network in the conveying line are divided into sections in a manner similar to block building, and a CAN bus network access unit in each section is in a similar structure. Each CAN bus network access unit can be communicatively connected to another CAN bus network access unit in the CAN through an internal bus transceiver, thereby connecting to form a control network. Moreover, each CAN bus network access unit includes a structure with dual CAN buses, where a first port is connected to a first CAN bus. According to whether a variable connection port which is other than the first port, is connected to the first CAN bus or connected to a second CAN bus, the CAN bus network access unit is determined to be a CAN bus network access unit within the CAN, or a CAN connected consecutively to a CAN bus network access unit in another CAN. Through this structure, serial communication between the plurality of CANs is implemented. Therefore, regardless of the length of the conveying line, the entire electric control network can be constructed like block building, thereby standardizing the electric control part used in the conveying line.

Because in this standardization method, the control components in the conveying line regions access buses through standard CAN bus network access units, and are in a dispersed control structure, centralized polling is not required, thereby ensuring the real-time performance and reducing the time delay. In timeliness, a communication between the control components can be performed with a time delay of within <NUM> in the CAN bus network. The serial port communication manner requires host polling. The time delay of a medium-scale network is within <NUM>, and the time delay of a large-scale network (for example, with <NUM> nodes) may be more than <NUM>.

Additionally, costs of the CAN bus transceiver in the foregoing technology are equivalent to costs of an Ethernet chip. However, because there is no network switch required, the costs of network wiring and device management will be greatly reduced.

A conveying line <NUM> and an electric control network thereof according to some embodiments of the present disclosure are described below with reference to <FIG>.

The conveying line <NUM> is an aggregation of all conveying devices for completing article conveying, such as a conveying belt and a conveyor. In current logistics storage and distribution, the conveying line <NUM> may reach hundreds or thousands of meters. Therefore, in a conventional conveying device, it is impractical for a single electric control component to control running of the entire conveying device. The conveying line <NUM> needs to be divided into sections, and each section is a conveying line region <NUM>. In each conveying line region <NUM>, one or more control components <NUM> control running of a conveying device in the region <NUM>, and these control components communicate with each other through an electric control network <NUM>. For example, for a <NUM>-meter conveying line, there is a conveying line region <NUM> every <NUM> meters, and one or more control components <NUM> are arranged in each conveying line region <NUM>, to control running of a device in conveying line the region <NUM>.

A CAN bus network access unit <NUM> is arranged in each conveying line region <NUM>, and is responsible for connecting the control component <NUM> to the electric control network <NUM> in the conveying line region <NUM>. A control signal of the control component <NUM> through the CAN bus network access unit <NUM> is transferred to a control component <NUM> connected to another CAN bus network access unit <NUM> on the electric control network <NUM>, to perform mutual communication between the control components <NUM>. These CAN bus network access units <NUM> connected in series form the electric control network <NUM>.

The electric control network <NUM> in the conveying line <NUM> in <FIG> includes a plurality of CANs <NUM>. Each CAN <NUM> is illustrated in an elliptical part in a bold-line box in <FIG> illustrates a first CAN <NUM>, a second CAN <NUM>, and a third CAN <NUM>, but a person skilled in the art understands that the electric control network <NUM> may alternatively include another quantity of CANs, for example, <NUM>, <NUM>, or <NUM>.

CAN is an abbreviation of controller area network, and is one of internationally relatively widely applied on-site buses. In a CAN, a message of a node is broadcasted to all other nodes in the CAN. Therefore, it may be considered that each message in a CAN is sent to all nodes in the CAN through a same CAN bus. Messages in different CANs are sent by using different CAN buses. Because the conveying line may have a length of a few kilometers and contain thousands of or even tens of thousands CAN bus network access units <NUM>, and a coverage distance of a CAN cannot cover such a length, the form of a plurality of CANs <NUM> connected in series is used in embodiments of the present disclosure. A routing CAN bus network access unit <NUM> is connected between two neighboring CANs <NUM>. The routing CAN bus network access unit <NUM> belongs to both of the two neighboring CANs <NUM>, and is responsible for forwarding (broadcasting) a message of a CAN <NUM> to another CAN <NUM>. Because the two CANs <NUM> transmit messages by using different CAN buses, it is usually required that the routing CAN bus network access unit <NUM> can be connected to both of the two CAN buses at the same time, and can forward a message on a CAN bus to another CAN bus. Routing CAN bus network access units <NUM> shown in <FIG> include C4, C8, and C11, where CX is an identifier of an Xth CAN bus network access unit in the figure.

In addition to the routing CAN bus network access unit <NUM>, another type of CAN bus network access unit <NUM> is an internal CAN bus network access unit <NUM>, that is, a CAN bus network access unit within the CAN <NUM>, and other than a routing CAN bus network access unit <NUM>. Because messages are transmitted within a CAN <NUM> by using a same CAN bus, a message on one CAN <NUM> is not required to forwarded to another CAN <NUM>. Internal CAN bus network access units <NUM> shown in <FIG> include C1, C2, C3, C5, C6, C7, C9, and C10.

A specific structure of a CAN bus network access unit <NUM> according to some embodiments of the present disclosure is described in detail below with reference to <FIG>. As described above, the CAN bus network access unit <NUM> refers to a component responsible for connecting a control component <NUM> to the electric control network <NUM>, where the control component <NUM> is in a conveying line region <NUM> of the conveying line <NUM>. The control component <NUM> refers to a component that may monitor bus messages in the conveying line region <NUM> and send a bus message at an appropriate moment, to communicate with a control component <NUM> in another conveying line region <NUM>. The electric control network <NUM> refers to an electric control part of the conveying line <NUM>, and is configured to transmit a control signal for a physical conveying device in the conveying line <NUM>.

As shown in <FIG>, the CAN bus network access unit <NUM> includes: a first CAN bus <NUM>, a second CAN bus <NUM>, a first CAN bus transceiver <NUM>, a second CAN bus transceiver <NUM>, a first port <NUM>, and a plurality of variable connection ports <NUM> including a second port <NUM>, a third port <NUM>, and a fourth port <NUM>. At least one of the plurality of variable connection ports <NUM> may be connected to any bus of the first CAN bus <NUM> and the second CAN bus <NUM>, and may alternatively be connected to neither of the two buses. As described above, when the CAN bus network access unit <NUM> is used as the routing CAN bus network access unit <NUM>, different CAN buses need to be connected consecutively. In this case, one of the second port <NUM>, the third port <NUM>, and the fourth port <NUM> may be connected to the second CAN bus <NUM>. Because the first port <NUM> is always connected to the first CAN bus <NUM>, different CAN buses connected consecutively is realized. When the CAN bus network access unit <NUM> is used as the internal CAN bus network access unit <NUM>, a same CAN bus needs to be connected consecutively. In this case, the second port <NUM>, the third port <NUM>, and the fourth port <NUM> may be connected to the first CAN bus <NUM>. Because the first port <NUM> is always connected to the first CAN bus <NUM>, a same CAN bus connected consecutively is realized.

Although the plurality of variable connection ports <NUM> including the second port <NUM>, the third port <NUM>, and the fourth port <NUM> are described above exemplarily, the plurality of variable connection ports may actually alternatively include another quantity of ports, for example, may further include a fifth port and a sixth port according to needs, and may alternatively include only the second port <NUM> and the third port <NUM>.

The first CAN bus transceiver <NUM> is connected to the first CAN bus <NUM>, and is configured to communicate with a first CAN bus transceiver <NUM> of another CAN bus network access unit <NUM> in the electric control network <NUM>, thereby establishing a first CAN communication. The second CAN bus transceiver <NUM> is connected to the second CAN bus <NUM>, and is configured to communicate with a second CAN bus transceiver <NUM> of the another CAN bus network access unit <NUM> in the electric control network <NUM>. It should be noted that, although a plurality of CAN bus network access units <NUM> sequentially connected in each CAN are shown in <FIG> (for example, the CAN bus network access unit C1 is connected to the CAN bus network access unit C2, and the CAN bus network access unit C2 is connected to the CAN bus network access unit C3), actually, after a CAN bus network access unit <NUM> sends a message through its first CAN bus transceiver <NUM> or second CAN bus transceiver <NUM>, a first CAN bus transceiver <NUM> or second CAN bus transceiver <NUM> of other CAN bus networks access unit <NUM> that are connected to the first bus or the second bus may receive the message. As long as a CAN bus network access unit <NUM> is connected to a bus, sending a message may be considered as a type of broadcast. Therefore, in <FIG>, if the CAN bus network access unit C2 sends a message, because the CAN bus network access units C1, C3, and C4 are all connected to the first CAN bus <NUM>, all the CAN bus network access units C1, C3, and C4 receive the message, that is, the message is broadcast to the CAN bus network access units C1, C3, and C4.

As shown in <FIG>, the first port <NUM> is connected to the first CAN bus <NUM>. At least one of the plurality of variable connection ports <NUM> is connected to one of the first CAN bus <NUM> and the second CAN bus <NUM>, or is connected to neither the first CAN bus <NUM> nor the second CAN bus <NUM>. Therefore, the CAN bus network access units <NUM> can be in different type according to the different connections, that is, a straight-line CAN bus network access unit or a transplanter CAN bus network access unit, which are described in detail below.

The CAN bus network access unit <NUM> shown in <FIG> may be applied in a logistics scenario, and is used as a network access unit of the electric control network <NUM> in the conveying line <NUM>. At least one of the first port <NUM> and the plurality of variable connection ports <NUM> is connected to a control component <NUM> configured to control logistics conveying in the conveying line <NUM>.

Moreover, the CAN bus network access unit <NUM> shown in <FIG> may be applied in a production line scenario, and is used as a network access unit of the electric control network in the product production line. At least one of the first port <NUM> and the plurality of variable connection ports <NUM> is connected to a control component <NUM> configured to control the product production in the product production line. There are links such as raw material feeding, mixing, stirring, baking, drying in the shade, and packaging on the product production line. In each link, scattered control components for controlling machine operating of these links are required, and these control components are connected to each other and communicate with each other through control buses. Therefore, the control components and the control buses form an electric control network in the product production line. If the production line is sufficiently long, the production line needs to be divided into sections of production line regions. In each production line region, one or more corresponding control components control various operations in the production line region. The electric control network is realized in a form of a plurality of CANs connected in series. Each CAN includes a plurality of CAN bus network access units, and each CAN bus network access unit corresponds to a production line region, and is connected to the control component(s) in the production line region. In this way, the production line and the electric control network in the production line are divided into sections in a manner similar to block building, and the CAN bus network access units in each section are in a similar structure.

Moreover, the CAN bus network access unit <NUM> shown in <FIG> can be applied in an Internet of Things scenario, and the CAN bus network access unit <NUM> is a network access unit in the Internet of Things. At least one of the first port <NUM> and the plurality of variable connection ports <NUM> is connected to an Internet of Things device for accessing the Internet of Things, for example, a signal lamp, a camera, a road horizontal bar control apparatus, or a transportation control node. The entire Internet of Things is divided into a plurality of Internet of Things regions, Internet of Things devices in an Internet of Things region are connected to CAN buses through the CAN bus network access unit <NUM>. CAN buses in an Internet of Things region and connected Internet of Things devices are considered as a CAN as a whole.

<FIG> is a logical structural diagram of a CAN bus network access unit <NUM>, according to some embodiments of the present disclosure. The logical structural diagram blurs an internal connection relationship in the CAN bus network access unit <NUM> in <FIG>. The internal connection relationship is considered as a black box, and the CAN bus network access unit <NUM> is only considered as a box including four logical ports <NUM> to <NUM>. The connection relationship between each of the logical ports <NUM> to <NUM> and the first CAN bus <NUM> or the second CAN bus <NUM> is hidden. The logical ports <NUM> to <NUM> may be logical entries, and may alternatively be logical exits. The logical entry means that if a port is connected to the first CAN bus <NUM> or the second CAN bus <NUM>, and an input signal is provided to the CAN bus, the port is a logical entry. The logical exit means that if a port is connected to the first CAN bus <NUM> or the second CAN bus <NUM>, and a signal is outputted from the CAN bus to the port, the port is a logical exit. Because of being fixedly connected to the first CAN bus <NUM>, the first port <NUM> can be only a logical entry. Each port of the second port <NUM>, the third port <NUM>, and the fourth port <NUM> may be connected to the first CAN bus <NUM>, and may alternatively be connected to the second CAN bus <NUM>. When the port is connected to the first CAN bus <NUM>, the port just forms an exit of a signal of a logical entry of the first port <NUM>, i.e., a logical exit. When the port is connected to the second CAN bus <NUM>, the port is connected to a new CAN bus and inputs a signal to the new CAN bus, i.e., the port is a logical entry.

A straight-line CAN bus network access unit and a transplanter CAN bus network access unit are described in detail below.

The CAN bus network access unit <NUM> shown in <FIG> is a straight-line CAN bus network access unit if only the first port <NUM> and the third port <NUM> are used, and the second port <NUM> and the fourth port <NUM> are not used (the second port <NUM> and the fourth port <NUM> are shielded by a physical device, for example, closed by using a cover plate). In this case, the first port <NUM> is fixedly connected to the first CAN bus <NUM>, and is definitely a logical entry. The third port <NUM> can be only connected to only the first CAN bus <NUM> and is used as a logical exit. If the third port <NUM> is connected to the second CAN bus <NUM>, a signal flowing in from the first port <NUM> cannot flow out. Therefore, the third port <NUM> can be used only as a logical exit of the signal flowing in from the first port <NUM>, and is connected to the first CAN bus <NUM>. Any one of the second port <NUM> and the fourth port <NUM> is connected to neither the first CAN bus <NUM> nor the second CAN bus <NUM>.

The CAN bus network access unit <NUM> shown in <FIG> is a transplanter CAN bus network access unit if the first port <NUM>, the second port <NUM>, the third port <NUM>, and the fourth port <NUM> can be all used. In this case, the first port <NUM> is fixedly connected to the first CAN bus <NUM>, and is definitely a logical entry. The second port <NUM>, the third port <NUM>, and the fourth port <NUM> may be connected to the first CAN bus <NUM> and used as logical exits, or may be connected to the second CAN bus <NUM> and used as logical entries.

The routing CAN bus network access unit <NUM> is definitely a transplanter CAN bus network access unit. This is because, in order to forward a message from the first CAN bus <NUM> to the second CAN bus <NUM> by the routing CAN bus network access unit, the second port <NUM>, the third port <NUM>, and the fourth port <NUM> must be connected to the second CAN bus <NUM>. The internal CAN bus network access unit <NUM> can be a straight-line CAN bus network access unit or a transplanter CAN bus network access unit. Each internal CAN bus network access unit <NUM> in the electric control network shown in <FIG> is a straight-line CAN bus network access unit. In a CAN bus network access unit interconnection structure in <FIG>, each of the three internal CAN bus network access units <NUM> (e.g., CAN bus network access units A, B, and C) only has a first port <NUM> and a third port <NUM> used. Therefore all the three internal CAN bus network access units <NUM> (e.g., CAN bus network access units A, B, and C) are straight-line CAN bus network access unit. However, in a CAN bus network access unit interconnection structure in <FIG>, among the four internal CAN bus network access units <NUM> (e.g., CAN bus network access units A, B, C, and D), a first port <NUM>, a third port <NUM>, and a fourth port <NUM> of the CAN bus network access unit B are all used, where the fourth port <NUM> of the CAN bus network access unit B is connected to a first port <NUM> of the CAN bus network access unit D. In this case, although the CAN bus network access unit B is not the routing CAN bus network access unit <NUM>, a transplanter CAN bus network access unit can be used.

Additionally, a straight-line CAN bus network access unit (for example, CAN bus network access units A to C shown in <FIG>) may be connected to straight-line CAN bus network access units, and a straight-line CAN bus network access unit (for example, CAN bus network access units A, C, and D shown in <FIG>) may alternatively be connected to transplanter CAN bus network access units. However, a transplanter CAN bus network access unit (for example, a CAN bus network access unit B shown in <FIG>) can be only connected to a straight-line CAN bus network access unit.

To more typically illustrate how to transfer messages by CAN bus network access units <NUM> in different CANs, <FIG> shows an electric control network including only a first CAN <NUM> and a second CAN <NUM>. Since the electric control network includes only two CANs, message transfer between CAN bus network access units <NUM> in different CANs can be better indicated.

As shown in <FIG>, the first CAN <NUM> and the second CAN <NUM> have a common routing CAN bus network access unit <NUM>, i.e., C4. In addition to the routing CAN bus network access unit <NUM>, the first CAN <NUM> further includes <NUM> internal CAN bus network access units <NUM>, i.e., C1 to C3. In addition to the routing CAN bus network access unit <NUM>, the second CAN <NUM> further includes <NUM> internal CAN bus network access units <NUM>, i.e., C5 to C7. Each of these CAN bus network access units has the structures shown in <FIG> and <FIG>. Each of the internal CAN bus network access units C1 to C3 can be a straight-line CAN bus network access unit, that is, the first port <NUM> and the third port <NUM> are connected to the first CAN bus <NUM>, and the remaining ports are not used. Each of the internal CAN bus network access units C1 to C3 can alternatively be a transplanter CAN bus network access unit, that is, the first port <NUM> is connected to the first CAN bus <NUM>, and the second port <NUM>, the third port <NUM>, and the fourth port <NUM> may be connected to the first CAN bus <NUM> or the second CAN bus <NUM>. However, actually the second port <NUM>, the third port <NUM>, and the fourth port <NUM> are only allowed to connect to the first CAN bus <NUM>. The structures of the internal CAN bus network access units C5 to C7 are similar. The routing CAN bus network access unit C4 is in the form of a transplanter CAN bus network access unit, that is, the first port <NUM> is connected to the first CAN bus <NUM>, and at least one of the second port <NUM>, the third port <NUM>, and the fourth port <NUM> is connected to the second CAN bus <NUM>.

Transmitting messages in the electric control network includes two cases. One case is that messages are transmitted between CAN bus network access units <NUM> of a same CAN, and the other case is that messages are transmitted between CAN bus network access units <NUM> of different CANs.

For the case that messages are transmitted between CAN bus network access units <NUM> of a same CAN, as shown in <FIG>, a message sending CAN bus network access unit <NUM> is C1, and a message receiving CAN bus network access unit <NUM> is C3. The message sending CAN bus network access unit <NUM> refers to a CAN bus network access unit for sending a control message to the electric control network, and then transferring the control message to another CAN bus network access unit on the electric control network. The message receiving CAN bus network access unit <NUM> refers to a CAN bus network access unit for receiving the control message sent by the message sending CAN bus network access unit <NUM>. The message sending CAN bus network access unit <NUM> and the message receiving CAN bus network access unit <NUM> are both located in the first CAN <NUM>.

The message sending CAN bus network access unit <NUM> sends a directing message which is needed to reach the message receiving CAN bus network access unit <NUM>. The directing message refers to a message needing to be only sent to a particular target (e.g., a message receiving CAN bus network access unit), and the remaining message receiving CAN bus network access units may discard the message after receiving the message. The directing message contains an identifier (for example, C3) of the message receiving CAN bus network access unit <NUM> that the message needs to reach and message content. During sending, first, the message sending CAN bus network access unit <NUM> broadcasts a directing message to all other CAN bus network access units in the first CAN <NUM> through a transceiver thereof, where the directing message carries an identifier of the message receiving CAN bus network access unit <NUM> that the directing message needs to reach. If a CAN bus network access unit <NUM> receiving the directing message is an internal CAN bus network access unit <NUM>, the CAN bus network access unit determines whether the identifier of the message receiving CAN bus network access unit contained in the message matches its own identifier. If the identifier of the message receiving CAN bus network access unit contained in the massage matches the identifier of the internal CAN bus network access unit, indicating that the internal CAN bus network access unit is the message receiving CAN bus network access unit <NUM> that the directing message needs to reach, the internal CAN bus network access unit reserves the directing message. If the identifier of the message receiving CAN bus network access unit contained in the massage does not match the identifier of the internal CAN bus network access unit, the internal CAN bus network access unit discards the message. If a CAN bus network access unit <NUM> receiving the directing message is the routing CAN bus network access unit <NUM>, and it is determined that the identifier of the message receiving CAN bus network access unit contained in the message is in a first CAN bus network access unit identifier list, indicating that the message has been received by a CAN bus network access unit <NUM> in the first CAN <NUM>, the directing message is discarded.

As shown in <FIG>, the message sending CAN bus network access unit C1 broadcasts a directing message to the CAN bus network access units C2 and C3 in the first CAN <NUM>. After receiving the directing message, the CAN bus network access unit C2 compares the identifier (i.e., C3) of the message receiving CAN bus network access unit <NUM> in the message with its own identifier C2. Finding that the identifier C2 does not match the identifier (i.e., C3) of the message receiving CAN bus network access unit <NUM>, the CAN bus network access unit C2 discards the message. After receiving the directing message, the CAN bus network access unit C3 compares the identifier (i.e., C3) of the message receiving CAN bus network access unit <NUM> in the directing message with its own identifier C3. The CAN bus network access unit C3 recognized that the CAN bus network access unit C3 is the message receiving CAN bus network access unit <NUM>, then reserves the message.

For the case that messages are transmitted between CAN bus network access units <NUM> of different CANs, as shown in <FIG>, the message sending CAN bus network access unit <NUM> is C1, located in the first CAN <NUM>. The message receiving CAN bus network access unit <NUM> is C6, located in the second CAN <NUM>.

The message sending CAN bus network access unit <NUM> broadcasts a directing message to another CAN bus network access unit <NUM> in the first CAN <NUM> through a first CAN transceiver <NUM>, and the directing message contains an identifier of the message receiving CAN bus network access unit <NUM>. After receiving the message, the internal CAN bus network access unit <NUM> receiving the directing message in the first CAN <NUM> determines that the identifier of the message receiving CAN bus network access unit <NUM> contained in the message does not match its own identifier, and discards the message. After receiving the message, the routing CAN bus network access unit <NUM> between the first CAN <NUM> and the second CAN <NUM> determines that the identifier of the message receiving CAN bus network access unit <NUM> contained in the message is not in the first CAN bus network access unit identifier list, and broadcasts the directing message to all CAN bus network access units in the second CAN <NUM> through a second CAN transceiver <NUM>. The CAN bus network access unit <NUM> receiving the directing message in the second CAN <NUM> determines whether the contained identifier of the message receiving CAN bus network access unit <NUM> matches its own identifier If the identifier of the message receiving CAN bus network access unit contained in the massage matches the identifier of the CAN bus network access unit <NUM>, indicating that the internal CAN bus network access unit <NUM> is the message receiving CAN bus network access unit <NUM>, the internal CAN bus network access unit reserves the directing message. If the identifier of the message receiving CAN bus network access unit contained in the massage does not match the identifier of the internal CAN bus network access unit, the internal CAN bus network access unit discards the message.

As shown in <FIG>, the message sending CAN bus network access unit C1 broadcasts a directing message to the CAN bus network access units C2 and C3 in the first CAN <NUM> through the first CAN transceiver <NUM>. The CAN bus network access unit C2 compares an identifier C6 of the message receiving CAN bus network access unit <NUM> in the directing message with its own identifier C2. Finding that the identifiers do not match each other, indicating that the CAN bus network access unit C2 is not the message receiving CAN bus network access unit <NUM>, and the CAN bus network access unit C2 discards the message. The CAN bus network access unit C3 compares the identifier C6 of the message receiving CAN bus network access unit <NUM> in the directing message with its own identifier C3. Finding that the identifiers do not match each other, the CAN bus network access unit C3 discards the message. CAN bus network access unit C4 is a routing CAN bus network access unit <NUM>. In this case, the routing CAN bus network access unit <NUM> compares the identifier C6 of the message receiving CAN bus network access unit <NUM> contained in the message with the first CAN bus network access unit identifier list, and finds that the identifier is not in the first CAN bus network access unit identifier list, meaning that the message receiving CAN bus network access unit <NUM> is not in the first CAN <NUM>. Therefore, the routing CAN bus network access unit <NUM> should broadcast, in the second CAN <NUM>, the directing message to the CAN bus network access units C5 to C7 in the second CAN <NUM> through the second CAN transceiver <NUM>. The CAN bus network access unit C5 determines that the identifier C6 of the message receiving CAN bus network access unit <NUM> contained in the message does not match its own identifier C5, indicating that the CAN bus network access unit C5 itself is not the message receiving CAN bus network access unit <NUM>, and therefore discards the message. The CAN bus network access unit C6 determines that the identifier C6 of the message receiving CAN bus network access unit <NUM> contained in the message matches its own identifier C6, indicating that the CAN bus network access unit C6 itself is the message receiving CAN bus network access unit <NUM>, and therefore reserves the directing message. The CAN bus network access unit C7 determines that the identifier C6 of the message receiving CAN bus network access unit <NUM> contained in the message does not match its own identifier C7, indicating that the CAN bus network access unit C7 itself is not the message receiving CAN bus network access unit <NUM>, and therefore discards the message.

If there are more than two CANs, it is possible that the message receiving CAN bus network access unit <NUM> still cannot be found in the second CAN <NUM>, and therefore the message may be forwarded to another CAN by a routing CAN bus network access unit <NUM> between the second CAN <NUM> and another CAN, until the message receiving CAN bus network access unit <NUM> is found. For example, in <FIG>, in addition to the first CAN <NUM> and the second CAN <NUM>, there is further a third CAN <NUM>. It is assumed that the message sending CAN bus network access unit is C1 and the message receiving CAN bus network access unit is C10. In this case, a CAN bus network access unit C8 between the second CAN <NUM> and the third CAN <NUM> can also receive the message. The routing CAN bus network access unit C8 compares the identifier C10 of the message receiving CAN bus network access unit <NUM> contained in the message with the second CAN bus network access unit identifier list, and finds that the identifier C10 is not in the second CAN bus network access unit identifier list, meaning that the message receiving CAN bus network access unit C10 is not in the second CAN <NUM>, and broadcasts the directing message to the CAN bus network access units C9 to C11 in the third CAN <NUM>. The CAN bus network access unit C9 determines that the identifier C10 of the message receiving CAN bus network access unit <NUM> contained in the message does not match its own identifier C9, indicating that the CAN bus network access unit C9 itself is not the message receiving CAN bus network access unit <NUM>, and therefore discards the message. C10 determines that the identifier C10 of the message receiving CAN bus network access unit <NUM> contained in the message matches its own identifier C10, indicating that the CAN bus network access unit itself is the message receiving CAN bus network access unit <NUM>, and therefore reserves the directing message. The CAN bus network access unit C11 determines that the identifier C10 of the message receiving CAN bus network access unit <NUM> contained in the message does not match its own identifier C11, indicating that the CAN bus network access unit C11 itself is not the message receiving CAN bus network access unit <NUM>, and therefore discards the message.

As shown in <FIG>, a directing message processing method in an electric control network <NUM> is provided. The method is performed by a current CAN bus network access unit receiving a directing message in the electric control network. The method includes steps <NUM> to <NUM>.

At step <NUM>, whether the current CAN bus network access unit is an internal CAN bus network access unit or a routing CAN bus network access unit is determined.

At step <NUM>, if the current CAN bus network access unit is an internal CAN bus network access unit, whether the identifier of the message receiving CAN bus network access unit contained in the directing message matches the identifier of the current CAN bus network access unit is determined. If the identifiers match each other, the current CAN bus network access unit reserves the directing message. If the identifiers do not match each other, the current CAN bus network access unit discards the directing message.

At step <NUM>, if the current CAN bus network access unit is a routing CAN bus network access unit, whether the identifier of the message receiving CAN bus network access unit contained in the directing message is in a CAN bus network access unit identifier list of a CAN upstream from the routing CAN bus network access unit is determined. If the identifier of the message receiving CAN bus network access unit contained in the directing message is in the CAN bus network access unit identifier list of a CAN upstream from the routing CAN bus network access unit, the current CAN bus network access unit discards the directing message. If the identifier of the message receiving CAN bus network access unit contained in the directing message is not in the CAN bus network access unit identifier list of a CAN upstream from the routing CAN bus network access unit, the current CAN bus network access unit forwards the directing message to a CAN bus network access unit downstream from the routing CAN bus network access unit.

Because the specific process of the foregoing method has actually been shown in detail above with reference to <FIG> and <FIG>, details will not be described herein.

Through the mechanism of transferring a message between different CAN bus network access units <NUM> in a same CAN and the mechanism of transferring a message between CAN bus network access units <NUM> in different CANs, convenient transfer of a message in the electric control network <NUM> can be implemented. The transfer is completely performed dispersedly between CAN bus network access units <NUM>, and centralized polling is not required, thereby improving message transfer efficiency. Moreover, because there is no network switch device required, the costs of network wiring and device management are reduced.

There are thousands of control components <NUM> and thousands of CAN bus network access units <NUM> on a large-scale conveying line <NUM>, to complete electric control of devices on the entire large-scale conveying line <NUM>. These CAN bus network access units <NUM> include straight-line CAN bus network access units, and also include transplanter CAN bus network access units. Moreover, connection manners of ports are diversified, and particularly for a transplanter, connection manners of ports are quite flexible. To find the connection structure of the entire electric control network <NUM>, connection conditions of ports of each CAN bus network access unit <NUM> need to be manually investigated one by one, and a large quantity of manual costs are required. Some embodiments of the present disclosure further provide a method that can automatically detect connection conditions of ports of each CAN bus network access unit <NUM> in the electric control network <NUM>. In the method, a plurality of sequential scanning periods are set. In each scanning period, a connection relationship between each port in each CAN bus network access unit <NUM> and a first CAN bus <NUM> or a second CAN bus <NUM> is set. Each port sends a message according to a predetermined rule, and the message indicates a number of the port and a connection relationship between the port and the first CAN bus <NUM> or the second CAN bus <NUM>. When a port of another CAN bus network access unit <NUM> connected to the port receives the message, the another CAN bus network access unit <NUM> can recognize the connected CAN bus network access unit <NUM>, a number of the connected port, whether the port is a logical entry or exit, and other information, thereby automatically obtaining a connection condition of each port of the CAN bus network access unit <NUM>. Therefore, manual troubleshooting is not required, and efficiency of checking the connection condition of each port of the CAN bus network access unit <NUM> is increased.

It can be known from above that, for checking the connection condition of each port of the CAN bus network access unit <NUM>, in an aspect, each port of the CAN bus network access unit <NUM> connects to the first CAN bus <NUM> or the second CAN bus <NUM> in a plurality of sequential scanning periods and sends a message according to a predetermined rule, that is, status notification; and in another aspect, a status notification message is received and then processed. Actually, each port of each CAN bus network access unit <NUM> not only performs the former, but also performs the latter. The former is performed to cause a neighboring CAN bus network access unit <NUM> to find a status of the current CAN bus network access unit, and the latter is performed to check out a status of the neighboring CAN bus network access unit <NUM>. The former and the latter supplement each other. A status notification method for a CAN bus network access unit and a connection status detection method for a CAN bus network access unit are described below respectively.

As shown in <FIG>, a status notification method for a CAN bus network access unit, according to some embodiments of the present disclosure includes step <NUM> to <NUM>.

At step <NUM>, whether the CAN bus network access unit is a straight-line CAN bus network access unit or a transplanter CAN bus network access unit is determined.

At step <NUM>, if the CAN bus network access unit is the straight-line CAN bus network access unit, a first port is connected to a first CAN bus and a third port is connected to a second CAN bus in a first scanning period, a second scanning period, a third scanning period, and a fourth scanning period that are consecutive.

At step <NUM>, if the CAN bus network access unit is the transplanter CAN bus network access unit, the first port is connected to the first CAN bus and a second port, a third port, and a fourth port are connected to the second CAN bus in the first scanning period; the first port, the third port, and the fourth port are connected to the first CAN bus and the second port is connected to the second CAN bus in the second scanning period; the first port, the second port, and the fourth port are connected to the first CAN bus and the third port is connected to the second CAN bus in the third scanning period; and the first port, the second port, and the third port are connected to the first CAN bus and the fourth port is connected to the second CAN bus in the fourth scanning period.

At step <NUM>, messages are sent by using a first CAN bus transceiver and a second CAN bus transceiver and through ports connected to the first CAN bus transceiver and the second CAN bus transceiver, an identifier of the CAN bus network access unit, numbers of the buses corresponding to the transceivers, and numbers of the ports connected to the buses are notified.

The foregoing process is further described below in detail.

Before step <NUM>, the method may further include: a step of receiving a CAN control message in a scanning starting subtype sent by a detection starting CAN bus network access unit. This is a starting step for connection status detection of the CAN bus network access unit. Status notification and status detection of the entire CAN bus network access unit are started by a uniform message. In some embodiments, actions of CAN bus network access units <NUM> in the entire electric control network <NUM> are coordinated, to synchronize the status notification and the status detection (the reason is that only if one of two CAN bus network access units <NUM> connected to each other performs status notification and the other performs status detection, coordinated working can be performed), and in another aspect, a uniform time reference is provided to first, second, third, and fourth scanning periods mentioned below.

The detection starting CAN bus network access unit is a CAN bus network access unit <NUM> preset in the electric control network <NUM>, and sends a CAN control message in a scanning starting subtype in the whole network. Therefore, after receiving the CAN control message, a CAN bus network access unit <NUM> in the whole network begins to set, based on time of receiving the CAN control message or a time stamp in the received CAN control message, the first, second, third, and fourth scanning periods mentioned below. The CAN bus network access unit <NUM> sets connection statuses between different ports and the first CAN bus <NUM> or the second CAN bus <NUM> and sends different messages in the first, second, third, and fourth scanning periods. Another CAN bus network access unit <NUM> connected to a port of the CAN bus network access unit <NUM> receives the message, and recognizes a neighboring CAN bus network access unit <NUM> and connection status of ports based on the messages.

The CAN control message is a message that is specified in advance (for example, specified through a protocol) and that is used for sending a global control instruction in the entire electric control network <NUM>. This global control instruction is not limited to scanning starting, and may further perform another type of control, for example, timing control. CAN control messages used for different types of control may be differentiated by using subtypes. A CAN control message used for scanning starting of connection status detection of a CAN bus network access unit in the embodiments of the present disclosure is in a scanning starting subtype, and a CAN control message used for timing control is in a timing control subtype. A subtype may be embodied as a field of a CAN control message. After receiving a CAN control message, a CAN bus network access unit <NUM> views a field representing a subtype. If the field indicates a scanning starting subtype, the CAN bus network access unit <NUM> begins to prepare to set connection statuses between different ports and the first CAN bus <NUM> or the second CAN bus <NUM> and send different messages in the first, second, third, and fourth scanning periods mentioned below.

The detection starting CAN bus network access unit may send the CAN control message in the scanning starting subtype to all the CAN bus network access units <NUM> in the whole network in the following manner: The detection starting CAN bus network access unit broadcasts the CAN control message to all other detection starting CAN bus network access units in a CAN in which the detection starting CAN bus network access unit is located. After receiving the CAN control message, a routing CAN bus network access unit between the CAN and another CAN recognizes that the CAN control message is in the scanning starting subtype, and broadcasts the message to all other CAN bus network access units in the another CAN, and so on, until all CAN bus network access units in all CANs in the electric control network <NUM> obtain the CAN control message.

The electric control network <NUM> in <FIG> is taken as an example. It is assumed that C2 is a detection starting CAN bus network access unit. Because of being located in the first CAN <NUM>, C2 broadcasts a CAN control message to other CAN bus network access units <NUM> in the first CAN <NUM>, that is, C1, C3, and C4. A subtype field of the CAN control message indicates the scanning starting subtype. After receiving the CAN control message, the routing CAN bus network access unit C4 between the first CAN <NUM> and the second CAN <NUM> recognizes that the subtype field of the CAN control message indicates the scanning starting subtype, and broadcasts the message to all other CAN bus network access units in the second CAN <NUM>, that is, C5 to C8. After receiving the CAN control message, the routing CAN bus network access unit C8 between the second CAN <NUM> and the second CAN <NUM> recognizes that the subtype field of the CAN control message indicates the scanning starting subtype, and broadcasts the message to all other CAN bus network access units in the third CAN <NUM>, that is, C9 to C11. In this way, C1 to C11 all obtain the CAN control message, and therefore the subsequent first, second, third, and fourth scanning periods may be set based on time of receiving the CAN control message or a time stamp in the CAN control message, to perform the following status notification and status detection.

Although times at which the CAN bus network access units in the electric control network <NUM> receive the CAN control message are slightly different rather than synchronous in the foregoing process, the first, second, third, and fourth scanning periods are usually in an order of magnitude of about <NUM>, and therefore differences between the times of receiving the CAN control message may be ignored compared with <NUM>. Therefore, the subsequent first, second, third, and fourth scanning periods may be set based on the times of receiving the CAN control message. Additionally, a time stamp may be further set in the CAN control message. The time stamp has been added when the CAN control message is generated, and does not change with different times at which the CAN bus network access units receive the CAN control message. Therefore, if the subsequent first, second, third, and fourth scanning periods are set based on the time stamp, accuracy of setting the scanning periods can be improved better, to improve the detection effect.

Additionally, before the first scanning period, a first silent period can be set, and after the fourth scanning period, a second silent period can be set. The first silent period and the second silent period may be set to a length substantially the same as that of each of the first, second, third, and fourth scanning periods, that is, about <NUM>. In the first silent period, a connection status between each port and the first CAN bus <NUM> or the second CAN bus <NUM> is the same as that in the first scanning period, and a sent message is also the same as that in the first scanning period (a connection status between each port and the first CAN bus <NUM> or the second CAN bus <NUM> and a sent message in the first scanning period are described below). In the second silent period, a connection status between each port and the first CAN bus <NUM> or the second CAN bus <NUM> is the same as that in the fourth scanning period, and a sent message is also the same as that in the fourth scanning period (a connection status between each port and the first CAN bus <NUM> or the second CAN bus <NUM> and a sent message in the fourth scanning period are described below).

Regarding a role in setting the first silent period, in some embodiments, it provides a sufficient time for some CAN bus network access units <NUM> to prepare, which are not ready to begin to change statuses and send messages according to a rule of changing a connection status between a port and a CAN bus in the first, second, third, and fourth scanning periods. In subsequent connection status detection, only messages received in the first, second, third, and fourth scanning periods (details are described in the following connection status detection) are considered, and the first silent period is not considered. Therefore, the first silent period plays a buffering role. In another aspect, the first silent period is set to offset differences between times at which the CAN bus network access units <NUM> receive the CAN control message in the scanning starting subtype. In this way, even if there is a time difference, only the length of the first silent period is affected, and the first, second, third, and fourth scanning periods can still synchronously start and end.

A role in setting the second silent period is similar to that in setting the first silent period. A status in the fourth scanning period is kept in the second silent period, therefore, the second silent period play a status buffering role. Moreover, the CAN bus network access unit <NUM> failing to be detected in the fourth scanning period may continue to be detected in this buffering status.

In step <NUM>, because each CAN bus network access unit <NUM> has its own configuration memory which stores configuration parameters of the CAN bus network access unit <NUM> itself, it may be determined from these configuration parameters whether the CAN bus network access unit is a straight-line CAN bus network access unit or a transplanter CAN bus network access unit.

In step <NUM>, for the straight-line CAN bus network access unit, the first port <NUM> is connected to the first CAN bus <NUM> and the third port <NUM> is connected to the second CAN bus <NUM> in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period that are consecutive.

Additionally, in the first silent period before the first scanning period, and in the second silent period after the fourth scanning period, the first port <NUM> is connected to the first CAN bus <NUM>, and the third port <NUM> is connected to the second CAN bus <NUM> as well.

The reason for doing so is that, for the straight-line CAN bus network access unit, during actual working, only the first port <NUM> and the third port <NUM> are working, and during normal working, the first port <NUM> is connected to the first CAN bus <NUM> and the third port <NUM> is connected to the second CAN bus <NUM>. In this way, as long as a connection relationship between a port and a CAN bus is set according to actual use, whether the first port <NUM> is connected to a counterpart or the third port <NUM> is connected to a counterpart can be clearly indicated to another CAN bus network access unit <NUM> connected to the port with the port number of the port connected to the bus in the notification message in step <NUM>.

In step <NUM>, for the transplanter CAN bus network access unit, the first port <NUM> is connected to the first CAN bus <NUM> and the second port, the third port, and the fourth port <NUM> to <NUM> are connected to the second CAN bus <NUM> in the first scanning period; the first port <NUM>, the third port <NUM>, and the fourth port <NUM> are connected to the first CAN bus <NUM> and the second port <NUM> is connected to the second CAN bus <NUM> in the second scanning period; the first port <NUM>, the second port <NUM>, and the fourth port <NUM> are connected to the first CAN bus <NUM> and the third port <NUM> is connected to the second CAN bus <NUM> in the third scanning period; and the first port, the second port, and the third port <NUM> to <NUM> are connected to the first CAN bus <NUM> and the fourth port <NUM> is connected to the second CAN bus <NUM> in the fourth scanning period.

Additionally, in the first silent period before the first scanning period, similar to the first scanning period, the first port <NUM> is connected to the first CAN bus <NUM>, and the second port, the third port, and the fourth port <NUM> to <NUM> are connected to the second CAN bus <NUM>. In the second silent period after the fourth scanning period, similar to the fourth scanning period, the first port, the second port, and the third port <NUM> to <NUM> are connected to the first CAN bus <NUM>, and the fourth port <NUM> is connected to the second CAN bus <NUM>.

In the first scanning period, the meaning of connecting the first port <NUM> to the first CAN bus <NUM> and connecting the second port, the third port, and the fourth port <NUM> to <NUM> to the second CAN bus <NUM> is that, for the transplanter CAN bus network access unit, during normal use, the first port <NUM> should be connected to the first CAN bus <NUM>. The first port <NUM> is connected to the first CAN bus <NUM>, and the second port, and the third port, and the fourth port <NUM> to <NUM> are connected to the second CAN bus <NUM>. In this way, in step <NUM>, if in the first scanning period, a bus number corresponding to the transceiver in the notification message is <NUM>, the message is definitely sent by the first port <NUM>, thereby clearly indicating, to another CAN bus network access unit <NUM> connected to the port, that the first port <NUM> is connected to a counterpart.

If the first port <NUM> being connected to the first CAN bus <NUM> and the second port, the third port, and the fourth port <NUM> to <NUM> being all connected to the second CAN bus <NUM> in the first scanning period is to clearly indicate whether the first port <NUM> is connected to the first CAN bus <NUM>, the meaning of connecting the first port <NUM>, the third port <NUM>, and the fourth port <NUM> to the first CAN bus <NUM> and connecting the second port <NUM> to the second CAN bus <NUM> in the second scanning period is to clearly indicate whether the second port <NUM> is connected to the second CAN bus <NUM>. Only the second port <NUM> is connected to the second CAN bus <NUM> in the second scanning period in this case. Therefore, if a CAN bus network access unit <NUM> receives a notification message in the second scanning period, where the notification message indicates that a bus number is <NUM>, it may be clearly known that a second port <NUM> of another CAN bus network access unit <NUM> is connected to the second CAN bus.

Similarly, the first port <NUM>, the second port <NUM>, and the fourth port <NUM> being connected to the first CAN bus <NUM> and the third port <NUM> being connected to the second CAN bus <NUM> in the third scanning period, is to clearly indicate whether the third port <NUM> is connected to the second CAN bus <NUM>. The first port, the second port, and the third port <NUM> to <NUM> being connected to the first CAN bus <NUM> and the fourth port <NUM> being connected to the second CAN bus <NUM> in the fourth scanning period, is to clearly indicate whether the fourth port <NUM> is connected to the second CAN bus <NUM>.

In step <NUM>, messages are sent by using the first CAN bus transceiver and the second CAN bus transceiver, and an identifier of the CAN bus network access unit, a bus number corresponding to the transceivers, and a port number of the port connected to the bus are notified through ports connected to the first CAN bus transceiver and the second CAN bus transceiver.

An identifier of a CAN bus network access unit is a unique flag allocated to the CAN bus network access unit, and can uniquely indicate "who is" the identifier of the CAN bus network access unit. In the message, this identifier is used for notifying another CAN bus network access unit <NUM> connected to the current CAN bus network access unit <NUM> of a CAN bus network access unit <NUM> whose port is connected to a counterpart.

The bus number corresponding to the transceiver refers to whether the transceiver is connected to the first CAN bus <NUM> or the second CAN bus <NUM>. For example, the first CAN bus <NUM> may be represented with <NUM>, and the second CAN bus <NUM> may be represented with <NUM>.

The port number of the port connected to the bus refers to one of the first port <NUM>, the second port <NUM>, the third port <NUM>, and the fourth port <NUM> to which the bus is connected. For example, the first port <NUM> may be represented with <NUM>, the second port <NUM> may be represented with <NUM>, the third port <NUM> may be represented with <NUM>, and the fourth port <NUM> may be represented with <NUM>.

For the straight-line CAN bus network access unit, in step <NUM>, the first port is connected to the first CAN bus, and the third port is connected to the second CAN bus. Therefore, a message is sent by using the first CAN bus transceiver <NUM> and the identifier of the CAN bus network access unit, a bus number <NUM> (because the first CAN bus <NUM> is connected to the first CAN bus transceiver <NUM>), and a port number <NUM> (because the first port <NUM> is connected to the first CAN bus <NUM>) are notified through the first port <NUM> connected to the first CAN bus transceiver <NUM>. A message is sent by using the second CAN bus transceiver <NUM> and the identifier of the CAN bus network access unit, a bus number <NUM> (because the second CAN bus <NUM> is connected to the second CAN bus transceiver <NUM>), and a port number <NUM> (because the third port <NUM> is connected to the second CAN bus <NUM>) are notified through the third port <NUM> connected to the second CAN bus transceiver <NUM>.

For the transplanter CAN bus network access unit, in step <NUM>, in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period, connection relationships between ports and the first CAN bus <NUM> or the second CAN bus <NUM> are all set in different manners. In this case, it is relatively difficult to notify a port number in a message, and therefore only a bus number, that is, whether the first CAN bus <NUM> or the second CAN bus <NUM> corresponding to the CAN bus transceiver may be notified in the message. Then, the CAN bus network access unit <NUM> receiving the message sends a port query request to the current CAN bus network access unit <NUM>, and the current CAN bus network access unit <NUM> responds to this request, indicating a port number of a port connected to the bus. In this way, if the first CAN bus transceiver <NUM> sends a message, the message contains an identifier of the CAN bus network access unit, a bus number <NUM>, and a particular flag bit, where the bus number <NUM> indicates that the first CAN bus transceiver <NUM> corresponds to the first CAN bus <NUM>, and the particular flag bit indicates that the transplanter CAN bus network access unit sends a message (for example, <NUM>). If the second CAN bus transceiver <NUM> sends a message, the message contains an identifier of the CAN bus network access unit, a bus number <NUM>, and a particular flag bit, where the bus number <NUM> indicates that the second CAN bus transceiver <NUM> corresponds to the second CAN bus <NUM>.

As shown in <FIG>, a connection status detection method for a CAN bus network access unit according to some embodiments of the present disclosure includes steps <NUM> to <NUM>.

At step <NUM>, for a to-be-detected port of the CAN bus network access unit, if the to-be-detected port receives, in a first scanning period, a second scanning period, a third scanning period, and a fourth scanning period that are consecutive, a message notifying an identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>, the to-be-detected port is determined to be connected to a straight-line CAN bus network access unit, and the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a first port of the straight-line CAN bus network access unit, and the first port is a logical entry.

At step <NUM>, if the to-be-detected port receives, in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period that are consecutive, a message notifying the identifier of the CAN bus network access unit, a bus number <NUM>, and a port number <NUM>, the to-be-detected port is determined to be connected to a straight-line CAN bus network access unit, and the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a third port of the straight-line CAN bus network access unit, and the third port is a logical exit.

At step <NUM>, if the to-be-detected port receives, in the first scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM>, and a particular flag bit, the to-be-detected port is determined to be connected to a transplanter CAN bus network access unit, and the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a first port of the straight-line CAN bus network access unit, and the first port is a logical entry.

At step <NUM>, if the to-be-detected port receives, in the second scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a second port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the second port is a logical exit; and in a case of the bus number <NUM>, the second port is a logical entry.

At step <NUM>, if the to-be-detected port receives, in the third scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a third port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the third port is a logical exit; and in a case of the bus number <NUM>, the third port is a logical entry.

At step <NUM>, if the to-be-detected port receives, in the fourth scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, the identifier of the CAN bus network access unit is recorded. The to-be-detected port is connected to a fourth port of the straight-line CAN bus network access unit, and in a case of the bus number <NUM>, the fourth port is a logical exit; and in a case of the bus number <NUM>, the fourth port is a logical entry.

In the status notification method described above in the embodiments of the present disclosure, for the straight-line CAN bus network access unit, the message notified by the CAN bus network access unit has the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM> corresponding to the transceiver, and the port number <NUM> or <NUM> the bus connected to, but has no particular flag bit (for example, <NUM>). For the transplanter CAN bus network access unit, the message notified has the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM> corresponding to the transceiver, and the particular flag bit. Therefore, whether the to-be-detected port is connected to a straight-line CAN bus network access unit or a transplanter CAN bus network access unit can be determined according to whether there is the particular flag bit in the message.

If there is no particular flag bit, the to-be-detected port is connected to a straight-line CAN bus network access unit, and in steps <NUM> and <NUM>, which port of the straight-line CAN bus network access unit is connected and whether the port is a logical entry or a logical exit can be further determined. Specifically, if a message including an identifier of the straight-line CAN bus network access unit, the bus number <NUM>, and the port number <NUM> is received, the first port <NUM> of the straight-line CAN bus network access unit can be determined to be connected according to the port number <NUM>. Because of being connected to the first CAN bus <NUM>, the first port <NUM> plays a role of a logical entry, and is a logical entry. Because the to-be-detected port is connected to the logical entry of the straight-line CAN bus network access unit, the to-be-detected port itself should be a logical exit of the current CAN bus network access unit. Specifically, if a message including an identifier of the straight-line CAN bus network access unit, the bus number <NUM>, and the port number <NUM> is received, the third port <NUM> of the straight-line CAN bus network access unit is determined to be connected according to the port number <NUM>. Because of being connected to the second CAN bus <NUM>, the third port <NUM> plays a role of a logical exit, and is a logical exit. Because the to-be-detected port is connected to the logical exit of the straight-line CAN bus network access unit, the to-be-detected port itself should be a logical entry of the current CAN bus network access unit.

Connection statuses between a port and a CAN bus for the straight-line CAN bus network access unit in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period are all the same. Therefore, the foregoing process may be performed at any time in the first scanning period, the second scanning period, the third scanning period, and the fourth scanning period. However, in some embodiments, it may be specified that the foregoing process is performed only in the first scanning period, or specified that the foregoing process is performed in any other scanning period.

If there is a particular flag bit, the to-be-detected port is connected to a transplanter CAN bus network access unit, and in steps <NUM> to <NUM>, which port of the transplanter CAN bus network access unit is connected and whether the port is a logical entry or a logical exit may be determined with reference to the four scanning periods respectively. As described above, in the first scanning period, the first port <NUM> is connected to the first CAN bus <NUM>, and the second port, the third port, and the fourth port <NUM> to <NUM> are connected to the second CAN bus <NUM>. The connection of the first port <NUM> being set different from other ports is mainly to indicate whether the first port <NUM> is connected and whether the first port <NUM> plays a role of a logical entry or exit. In the second scanning period, the first port <NUM>, the third port <NUM>, and the fourth port <NUM> are connected to the first CAN bus <NUM>, and the second port <NUM> is connected to the second CAN bus <NUM>. The connection of the second port <NUM> being set different from other ports is mainly to indicate whether the second port <NUM> is connected and whether the second port <NUM> plays a role of a logical entry or exit. In the third scanning period, the first port <NUM>, the second port <NUM>, and the fourth port <NUM> being connected to the first CAN bus <NUM>, and the third port <NUM> being connected to the second CAN bus <NUM> is mainly to indicate whether the third port <NUM> is connected and whether the third port <NUM> plays a role of a logical entry or exit. In the fourth scanning period, the first port, the second port, and the third port <NUM> to <NUM> being connected to the first CAN bus <NUM>, and the fourth port <NUM> being connected to the second CAN bus <NUM> is mainly to indicate whether the fourth port <NUM> is connected and whether the fourth port <NUM> plays a role of a logical entry or exit. Therefore, whether the first port <NUM>, the second port <NUM>, the third port <NUM>, and the third port <NUM> are connected, and logical properties of these ports are respectively determined in the first, second, third, and fourth scanning periods.

In step <NUM>, whether the to-be-detected port is connected to the first port <NUM> of the transplanter CAN bus network access unit is mainly determined. If the to-be-detected port receives, in the first scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM>, and the particular flag bit, because the first CAN bus <NUM> is fixedly connected to the first port <NUM>, it can be directly determined without sending a query request that the to-be-detected port is connected to the first port <NUM> of the straight-line CAN bus network access unit. Moreover, because of being connected to the first CAN bus <NUM>, the first port <NUM> plays a role of a logical entry, and is a logical entry. Because the to-be-detected port is connected to the logical entry of the straight-line CAN bus network access unit, the to-be-detected port itself should be a logical exit of the current CAN bus network access unit.

In step <NUM>, whether the to-be-detected port is connected to the second port <NUM> of the transplanter CAN bus network access unit is mainly determined. If the to-be-detected port receives, in the second scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, it may be determined that the to-be-detected port is connected to a second port <NUM> of the straight-line CAN bus network access unit. In a case of the bus number <NUM>, the second port <NUM> is connected to the first CAN bus <NUM>, indicating that the second port is a logical exit, and the to-be-detected port itself should be a logical entry of the current CAN bus network access unit. In a case of the bus number <NUM>, the second port is a logical entry, and the to-be-detected port itself should be a logical exit of the current CAN bus network access unit.

In step <NUM>, whether the to-be-detected port is connected to the third port <NUM> of the transplanter CAN bus network access unit is mainly determined. If the to-be-detected port receives, in the third scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, it may be determined that the to-be-detected port is connected to a third port <NUM> of the straight-line CAN bus network access unit. In a case of the bus number <NUM>, the third port <NUM> is connected to the first CAN bus <NUM>, indicating that the third port is a logical exit, and the to-be-detected port itself should be a logical entry of the current CAN bus network access unit. In a case of the bus number <NUM>, the third port is a logical entry, and the to-be-detected port itself should be a logical exit of the current CAN bus network access unit.

In step <NUM>, whether the to-be-detected port is connected to the fourth port <NUM> of the transplanter CAN bus network access unit is mainly determined. If the to-be-detected port receives, in the fourth scanning period, a message notifying the identifier of the CAN bus network access unit, the bus number <NUM> or <NUM>, and a particular flag bit, and receives a port number <NUM> after sending a port query request, it may be determined that the to-be-detected port is connected to a fourth port <NUM> of the straight-line CAN bus network access unit. In a case of the bus number <NUM>, the fourth port <NUM> is connected to the first CAN bus <NUM>, indicating that the fourth port is a logical exit, and the to-be-detected port itself should be a logical entry of the current CAN bus network access unit. In a case of the bus number <NUM>, the fourth port is a logical entry, and the to-be-detected port itself should be a logical exit of the current CAN bus network access unit.

The process of performing connection status detection for a to-be-detected port of a CAN bus network access unit <NUM> is described above. After connection status detection is performed on each to-be-detected port of the CAN bus network access unit <NUM>, identifiers of CAN bus network access unit <NUM> connected to each to-be-detected port, port numbers of the connected CAN bus network access unit <NUM>, logical types of the connected ports, and logical properties of the to-be-detected ports may be recorded.

For example, a record result for a straight-line CAN bus network access unit C2 is as follows:.

A record result for a transplanter CAN bus network access unit C2 is as follows:.

As shown in Table <NUM> and Table <NUM>, for each CAN bus network access unit <NUM> in the electric control network, after recorded identifiers of a CAN bus network access unit <NUM> connected to each to-be-detected port thereof, port numbers of the connected CAN bus network access unit <NUM>, and whether the connected port is a logical entry or logical exit are recorded, a diagram of a port connection relationship between CAN bus network access units <NUM> in the electric control network may be automatically machine-generated.

Through the foregoing solution, in the mode of dual CAN networks, a port connection status between a straight-line CAN bus network access unit and a transplanter CAN bus network access unit can be intelligently found and completely found by a device through automatic scanning. Manual setting does not need to be performed during engineering operation and maintenance, and the on-site implementation costs (device debugging time and personnel costs) is greatly reduced. Therefore, this solution is simple and convenient, without error, and has an industry-leading advantage.

As shown in <FIG>, according to some embodiments of the present disclosure, a status notification apparatus <NUM> for a CAN bus network access unit <NUM> is provided. The CAN bus network access unit <NUM> includes: a first CAN bus <NUM> and a second CAN bus <NUM>; a first CAN bus transceiver <NUM> and a second CAN bus transceiver <NUM>, respectively connected to the first CAN bus <NUM> and the second CAN bus <NUM> and respectively configured to communicate with a first CAN bus <NUM> and a second CAN bus <NUM> in another CAN bus network access unit <NUM>; a first port <NUM>, connected to the first CAN bus <NUM>; and a second port, a third port, and a fourth port <NUM> to <NUM>; the CAN bus network access unit <NUM> is classified into a straight-line CAN bus network access unit and a transplanter CAN bus network access unit, where the third port <NUM> of the straight-line CAN bus network access unit is connected to the second CAN bus <NUM>, and any one of the second port <NUM> and the fourth port <NUM> is connected to neither the first CAN bus <NUM> nor the second CAN bus <NUM>; and any one of the second port <NUM>, the third port <NUM>, and the fourth port <NUM> of the transplanter CAN bus network access unit is connectable to the first CAN bus <NUM> or the second CAN bus <NUM>. The status notification apparatus <NUM> includes:.

Specific implementation of the modules in the status notification apparatus <NUM> has been described in the detailed description of the flowchart of the method with reference to <FIG>, and therefore is not described in detail.

As shown in <FIG>, according to some embodiments of the present disclosure, a connection status detection apparatus <NUM> for a CAN bus network access unit <NUM> is provided. The CAN bus network access unit <NUM> includes: a first CAN bus <NUM>; a second CAN bus <NUM>; a first CAN bus transceiver <NUM> and a second CAN bus transceiver <NUM>, respectively connected to the first CAN bus <NUM> and the second CAN bus <NUM> and respectively configured to communicate with a first CAN bus <NUM> and a second CAN bus <NUM> in another CAN bus network access unit <NUM>; a first port <NUM>, connected to the first CAN bus <NUM>; and a second port, a third port, and a fourth port <NUM> to <NUM>; the CAN bus network access unit <NUM> is classified into a straight-line CAN bus network access unit and a transplanter CAN bus network access unit, where the third port <NUM> of the straight-line CAN bus network access unit is connected to the second CAN bus <NUM>, and any one of the second port <NUM> and the fourth port <NUM> is connected to neither the first CAN bus <NUM> nor the second CAN bus <NUM>; and any one of the second port, the third port, and the fourth port <NUM> to <NUM> of the transplanter CAN bus network access unit is connectable to the first CAN bus <NUM> or the second CAN bus <NUM>. The connection status detection apparatus <NUM> includes:.

Specific implementation of the modules in the connection status detection apparatus <NUM> has been described in the detailed description of the flowchart of the method with reference to <FIG>, and therefore is not described in detail.

<FIG> is a specific structural diagram of a CAN bus network access unit <NUM> according to some embodiments of the present disclosure. Compared with <FIG>, <FIG> further illustrates control parts of the CAN bus network access unit <NUM> that are configured to perform the status notification method shown in <FIG> and the connection status detection method shown in <FIG>, that is, a memory <NUM> and a processing logic <NUM>. The processing logic <NUM> may be a processor, and may alternatively be a logical circuit configured to perform processing. The memory <NUM> is configured to store control instructions. The processing logic <NUM> is connected to the memory <NUM>, and configured to read the control instructions stored in the memory <NUM>, to perform the status notification method shown in <FIG> and the connection status detection method shown in <FIG>.

It can be understood that, the embodiments of this specification are all described in a progressive manner, for same or similar parts in the embodiments, refer to these embodiments, and descriptions of each embodiment focus on a difference from other embodiments. Especially, an apparatus embodiment is basically similar to a method described in a method embodiment, and therefore is described briefly. For related parts, reference is made to partial descriptions in other embodiments.

It should be understood that specific embodiments of this specification are described above. Other embodiments are within the scope of the claims. In some embodiments, the actions or steps in the claims may be performed in sequences different from those in the embodiments and expected results may still be achieved. In addition, the processes depicted in the accompanying drawings do not necessarily require an automotive particular order or a sequential order for implementing the expected results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

It should be understood that an element described in a singular form herein or displayed only one in the accompanying drawings does not represent that the element is limited to one. In addition, modules or elements described or shown as separate herein may be combined into a single module or element, and a module or an element described or shown herein as a single module or element may be split into a plurality of modules or elements.

Claim 1:
A controller area network, CAN, bus network access unit (<NUM>), comprising:
a first CAN bus (<NUM>);
a second CAN bus (<NUM>);
a first CAN bus transceiver (<NUM>);
a second CAN bus transceiver, (<NUM>) wherein
the first CAN bus transceiver (<NUM>) and the second CAN bus transceiver (<NUM>) are respectively communicatively coupled to the first CAN bus (<NUM>) and the second CAN bus (<NUM>) and are respectively configured to communicate with another first CAN bus (<NUM>) and another second CAN bus (<NUM>) in another CAN bus network access unit (<NUM>);
a first port (<NUM>), communicatively coupled to the first CAN bus (<NUM>); and
a plurality of variable connection ports (<NUM>) comprising a second port (<NUM>), a third port (<NUM>), and a fourth port (<NUM>), wherein the CAN bus network access unit (<NUM>) is configurable as a straight-line CAN bus network access unit and as a transplanter CAN bus network access unit by connecting the variable connection ports, wherein:
when the bus network access unit is the straight-line CAN bus network access unit, the third port (<NUM>) is communicatively coupled to the second CAN bus (<NUM>), and any one of the second port (<NUM>) and the fourth port (<NUM>) communicatively coupled to neither the first CAN bus (<NUM>) nor the second CAN bus (<NUM>); and
when the bus network access unit is the transplanter CAN bus network access unit, any one of the second port (<NUM>), the third port (<NUM>), and the fourth port (<NUM>) is connectable to the first CAN bus (<NUM>) or the second CAN bus (<NUM>).