KR100460905B1 - Identifier establish method of can message in vehicle - Google Patents

Abstract

In order to define the ID of the CAN protocol message in the vehicle, it is possible to analyze the CAN bus currently applied in the vehicle and to present a standard method of setting the ID of the CAN message so that the CAN bus can be operated efficiently.

The priority area for determining the priority of the CAN message using the 11-bit reference ID is defined as a 5-bit ID, and the Rx filter in the area indicating the receiving node is defined as a 6-bit ID.

Description

How to set ID of can message in vehicle {IDENTIFIER ESTABLISH METHOD OF CAN MESSAGE IN VEHICLE}

The present invention relates to a method of setting an ID of a CAN message. More particularly, the present invention proposes a standard method of analyzing a CAN bus applied to a vehicle and setting an ID of a CAN message. The present invention relates to an ID setting method of a can message in a vehicle that can be efficiently operated.

With the development of electronic control technology and the improvement of microcontroller performance, the number of electronic control devices used in vehicles is increasing. These electronic control devices are modular in function, effective and systematic development process, and optimal system configuration. In order to advance control system design technology and communication technology, standardization of network of vehicle and database of related data are essential.

The design of the vehicle network system consists of the CAN protocol based on the hierarchical structure of the network defined by the International Organization for Standardization (ISO), which determines the ID (identifier) of the message when constructing the vehicle network system using the CAN protocol. This is one of the most important tasks in network design.

This is because the priority of the message is determined by the ID (identifier), and thus the response time of the system is converted, and the method of processing the message varies according to the information contained in the ID (identifier).

The CAN protocol is defined in ISO 11898 and ISO 11519-2 as one of the standards for the physical layer and data link layer among the seven ISO / OSI layers.

The CAN protocol communicates by broadcasting, and data is transmitted in units of frames. Every frame has a unique ID (identifier), so all nodes on the network determine the ID (identifier) of the frame and transmit it. It is determined whether or not to communicate the message.

In addition, priority is given to each frame to mediate when a collision occurs on the communication bus.

The data of the CAN message transmitted through the network consists of signals to be transmitted. The signal means a minimum unit having meaning in the network, such as an input / output or a control input of a sensor or a driver.

In CAN networks, these signals are transmitted using messages, which are reconfigured into a CAN bus, taking into account the sender and receiver of the signal, the length of the signal, and the characteristics of the time such as the transmission cycle and deadline. Means that.

In other words, all data to be transmitted through the network is called a signal, and the message reconfigured into a form that can be transmitted via CAN is called a message.

In general, the CAN message in the vehicle is most used by controllers such as ECUs, TCUs, and TCSs connected to the power train system. The ID structure consists of a diagram as shown in FIG.

Referring to FIG. 3, the ID setting area is analyzed to include an area indicating priority and an area for distinguishing a message.

In the above priority area, 'ID 10 to ID 8' are allocated as IDs for the transmitting nodes, and 'ID 7 to ID 6' are assigned as IDs of messages in the same node.

Then, 'ID 5 to ID 0' are allocated as an area for message classification.

In addition, as shown in the diagram of FIG. 3, among the messages used in the power train system, the messages generated by the TCS controller module have the highest priority, followed by the message of the ECU controller (E () and the message of the TCU controller. Priority is defined.

In addition, the part defining priority between receiving nodes is 'ID 10 ~ ID 8' area, and the priority between messages included in the same node is defined in the area of 'ID 7 ~ ID 6'. Priority is determined based on the transmission period of the message.

However, in the same ECU controller messages (E # 1 to E4), E4 does not follow the rules of the message, in which case the utilization of the CAN bus is less than 12%.

Determining the priority of a message by applying the method described above does not give priority to the signal constituting the message or the transmission period of the message, which is the most important consideration in determining the ID of a message. There are disadvantages that are not desirable as a set rule.

In addition, when a new message occurs due to the addition of a new electronic control unit, there is no method to assign a message ID, and in terms of specification management, there are many communication specifications without a standard specification because it has to rely on the E㎳ company. The problem occurs.

The present invention has been invented to solve the above problems, the purpose of which is to analyze the CAN bus (BUS) currently applied in the vehicle to build a database for the CAN message in use, and based on this CAN A standardization method for setting the ID of a message is presented to provide efficiency in the operation of the CAN bus.

In other words, it provides the efficiency and extensibility of the function by using the data such as the sender and receiver of the message for the network message, the transmission period and the signal constituting the message.

1 is a block diagram of a data format for ID setting of a can message in a vehicle according to the present invention.

2 is a diagram illustrating the configuration of a message used in a hybrid vehicle in one embodiment.

3 is a message definition diagram of a receiving node defined through the ID setting method of the present invention for a message used in a hybrid vehicle according to one embodiment.

4 is a message definition diagram defined through the present invention for a message used in a hybrid vehicle in one embodiment.

5 is a structure diagram of ID setting of a CAN message for a controller of a power train system in a conventional vehicle.

The present invention for realizing the above object is a method of defining the ID of a CAN protocol message in a vehicle,

The priority area for determining the priority of the CAN message using the 11-bit reference ID is defined as a 5-bit ID, and the Rx filter in the area indicating the receiving node is defined as a 6-bit ID.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As can be seen in Figure 1 the ID setting of the can message in the vehicle according to the present invention defines the ID (identifier) setting for the CAN message using a standard ID (identifier) of 11 bits.

As can be seen from the figure, the ID (identifier) of the 11-bit CAN message is composed of a priority (Priority) to determine the priority and a region (Rx Filter) indicating the receiving node, the priority is determined It indicates the priority of the message according to the transmission period, the length of the message data, and the number of received signals. It consists of a 5-bit ID (identifier), which defines up to 32 messages.

The rule for determining the priority area is as follows.

Iii). The message with the shortest period of messages is the highest priority.

Ii). The fixed priority scheduling method is used, and the area is set to 0x00 to 0x1F.

Iii). If the message periods are the same, high priority is given to a message with a long data length in consideration of the transmission time of the message.

Iii). If the transmission period of the message and the data length are the same, a high priority is given to the message having a large number of signals included in the message.

Iii). If all of the above conditions are the same, high priority is given to the high priority message of the receiving node.

In addition, the rule for determining the area of the receiving node consisting of the six bits is as follows.

Iii). One bit represents one receiving node.

Ii). Since it has an ID (identifier) area of 6 bits, up to 6 nodes are represented.

Iii). It does not involve classifying incoming messages by software at the receiving node.

Iii). When the number of nodes is 6 or more, the nodes satisfying a specific condition set between the receiving nodes are grouped and represented.

The conditions for grouping nodes are nodes having the same processing period of a received message and nodes having a common signal to be processed.

Looking at the ID definition of the CAN message in the powertrain system of the hybrid vehicle, for example, through the ID definition of the CAN message based on the definition as described above is as follows.

The CAN message used in the power train system of the hybrid vehicle is set as shown in FIG. 2 attached thereto. If the message ID is redefined through the 11-bit standard described above, the Rx filter of the receiving node is shown in FIG. It is expressed as

In addition, in consideration of messages to be added later, priority areas of a message having a period of 10 ms and 160 ms are defined as 0x09 and 0x19, respectively.

That is, in the case of a message having a period less than 10 ms, the value of the priority area may have a value of 0x00 ~ 0x08. In the case of a message having a period between 10 ms and 160 ms, the value of the priority area is 0x12 ~ 0x18 The value of the priority area may have a value of 0x1C to 0x1F when the message has a period of 160 ms or more.

In addition, the Rx filter area of the receiving node determines its value by setting the bit representing the receiving node of the message as '1'.

Among the messages used in the powertrain system of the hybrid vehicle, all messages except B㎳1, B㎳2, and B㎳3 have a period of 10 ms. Among the messages having a period of 10 ms, the length of transmitted data is MCU2. Since it has the longest priority with 8 bytes and has the highest priority, the value of the priority area is '9'. Since the receiving node of this message is the HCU, the Rx filter value is '1' and the ID of MCU2 is defined as 0x241. .

Next, the TCU1 and ECU1 messages each have 7 bytes of data. Since the number of signals included in the TCU1 is greater than the number of signals contained in the ECU1, the TCU1 has a higher priority.

Therefore, the values of the priority range are 0xA and 0xB, respectively.

In addition, since TCU1 is an HCU and an ECU node, and ECU1 is an HCU node, a Rx filter value is defined as 0x11 and 0x1, and an ID of TCU1 is defined as 0x291 and an ID of ECU1 is defined as 0x2C1.

When the priority of message IDs is defined and finally arranged as described above, it is represented by a diagram as shown in FIG.

Therefore, if the ID of the CAN message is defined through the above standardization definition, the bus utilization increases approximately 20% or more even if the number of nodes and the number of messages increase.

As described above, in the present invention, in defining the ID of a CAN message, the message is first defined by a message having a fast transmission period, thereby eliminating a delay in processing a critical message due to a bus preemption of a message having a slow transmission period. As a result, the use efficiency of the bus is increased.

In addition, through the standardization of the addition of a unit using CAN communication or the identification of new communication messages, efficient design and specification management can be carried out without relying on the E㎳ company.

Claims (13)

In the method of defining the ID of a CAN protocol message in a vehicle Priority is determined for CAN messages using 11-bit reference ID, and the priority area including priority information of the message according to the transmission cycle, the length of the message data, and the number of received signals is defined as a 5-bit ID. And the reception filter of the region representing the reception node has one bit indicating one reception node and is defined by an ID of 6 bits. delete The method of claim 1, The priority area is a method for setting the ID of the can message in a vehicle, characterized in that for defining a maximum of 32 messages are displayed. The method of claim 1, And the priority area defines a message having the shortest period of the message as the highest priority. The method of claim 1, The priority area is determined by a fixed priority scheduling method, and the area is defined as 0x00 to 0x1F. The method of claim 1, And the priority area is defined by giving a high priority to a message having a long data length in consideration of the transmission time of the message when the message periods are the same. The method of claim 1, And the priority area is defined by giving a high priority to a message having a large number of signals included in the message when the message transmission period and the data length are the same. The method of claim 1, And the priority area is defined by assigning a high priority to a message having a high priority of a receiving node when all of the above conditions are the same. delete The method of claim 1, The area of the receiving node has a 6-bit ID area, so up to 6 nodes are represented. The method of claim 1, And the area of the receiving node does not involve sorting a received message by software. The method of claim 1, And the area of the receiving node is defined by grouping nodes satisfying a specific condition set between the receiving nodes when the number of nodes is 6 or more nodes. The method of claim 12, The condition for grouping the nodes is defined as nodes having the same processing cycle of the received message and having a common signal to be processed.