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Tools-CANdb++ Editor——File——CreateDatabase—— Select the bus template according to the function （ This article chooses Vector IL Basic Template.dbc）—— Create a database project XVehicle.dbc】

After creating a new template ,CANdb++Editor The navigation area of the will show the relationship between all objects in the network .

The navigation area automatically lists the current bus network architecture and pairs like , contain Networks、（ECUs、Network nodes）、（Environment variables、Messages and Signals）.

Bus description ——Networks（ Configure bus name , type ）

stay Networks（ The Internet ） Under a , List the bus networks currently simulated .

There can be multiple networks in the database , Each network consists of one or more ECU form ,ECU Through network nodes Communicate with each other .

Different vehicle manufacturers have different requirements for the whole vehicle individual CAN Name definitions are different , for example ,PowerTrain CAN、Body CAN、Comfort CAN etc. .

This chapter defines the network name as XVehicle1, The type is CAN. （ Right click XVehicle1, choice Edit Network Enter bus attribute editing , As shown in the figure below .

3. node ： Add a node description to the database ——Network Nodes

stay ECUs（ Electronic control unit ） Under a , Lists the electronic control units contained in the current network , They pass through Network nodes （Network Nodes） Realize the interaction of information . Usually ,ECU It corresponds to the network nodes one by one Of . When ECU As a gateway , One ECU It can contain multiple network nodes . stay CAN In the database , Double click a individual ECU You can see the ECU Corresponding network nodes and environment variables .

What we need to remind readers is , stay CAN The database cannot be created directly ECU,CANdb++ Will be creating Network nodes ——Network Nodes At the same time , Create a with the same name ECU.

So we create Network Nodes To create control panel nodes , The system automatically creates penel Corresponding simulation node .

establish Network Nodes node , Set node properties

Network Nodes（ Network nodes ） yes ECUs Communication interface , various ECU adopt Network Nodes Realization Sending and receiving information on the bus , Every Network Nodes Include the corresponding name and address . Right click in the navigation area Network Nodes, In the shortcut menu, select Create a new one named Engine Network nodes of , And set the address of the node to 0x1, As shown in the figure .

In the same way , Create another one called Door The node of （ The address is Ox2） And a name called Display The node of （ The address is 0x3）.

After creation , You can see that the system automatically generates the corresponding ECU node , Respectively in NetWorks and ECUs There's a show in all of them .

4. Communication signals （ message , The signal ）：

message ——Message——CAN Uploaded data

Messages（ message ） It is the data that the nodes on the bus communicate with each other .

In the database , Each message shall contain the following attributes （ The messages used in this example are CAN As defined in the specification document CAN2.0A standard CAN）. You can press the following 4 Understand memory by classification ：

【 Message structure 】：Name（ Message name ） CAN ID（CAN identifier ） DLC（Data Length Code, Data length ） Type（ Transfer type ） Cycle Time（ cycle ）
【 Included content 】：Signals（ The signal ）
【 Transceiver node 】Transmitters（ Sending node ） Receivers（ Receiving node ）
【 other 】： Layout（ Layout ） Attributes（ General properties ） Comment（ explain ）

To configure Message attribute

X-Vehicle-1 In Engineering , There are two kinds of messages ：DoorState,EngineState. Create messages and set corresponding attributes ：

Name	CAN ID	DLC	Type	Transmitters	Receivers	GenMsgCycleTime	GenMsgSendType
EngineState	0x150	2	CAN standard	Engine		100	Cyclic
DoorState	0x200	1	CAN standard	Door		200	Cyclic

To configure Message cycle

The signal ——Signal

Signal（ The signal ） It is the smallest unit of bus communication , A signal in the database consists of the following attributes .

【 Signal format 】：Name（ Signal name ） Length[Bits]（ Signal length ） Byte Order（ Byte order ）Value Type（ data type ） Unit（ Physical units ）
【 Value settings 】Init.Value（ Initial value ） Factor（ weighting ）Maximum（ Maximum ） Minimum（ minimum value ）
【 Value meaning description 】Value Table（ Numerical table ）
【 Which message is associated 】Messages（ message ）
【 Transceiver node 】Receivers（ Receiving node ）
【 other 】Attributes（ General properties ） ·Value Descriptions（ Numerical description ） ·Comment（ explain ）

X-Vehicle-1 There is 4 A signal ： Engine speed （EngineSpeed）、 Engine status （OnOff）、 Left door switch status （Door_L) And right door switch status （Door_R).

Signal configuration information

Add this... According to the corresponding attribute value 4 A signal ：

Signal	Message	Value Type	Length	Byte Order	Start Bit	Unit	Init Value	Factor	Offset	Min	Max	Value Table
Engine Speed	Engine State	Singed	15	Intel	0	r.p.m	0	1	0	0	5500	-
OnOff	Engine State	Unsigned	1	Intel	15	-	0	1	0	0	1
Door_L	DoorState	Unsigned	1	Intel	0	-	0	1	0	0	1	name vtSig _Door _Status
Door_L	DoorState	Unsigned	1	Intel	0	-	0	1	0	0	1	Value description ：0：close 1：open
Door_R	DoorState	Unsigned	1	Intel	2	-	0	1	0	0	1	name vtSig _Door _Status; Value description ：0：close 1：open

With EngineState As an example, the operation is shown in the following figure ：

The signal Signal Associated message Message：

StartBite Setup example ：

Configure the signal at different nodes Send and receive ：

Configuration example of node receiving signal ：

Value Table To configure

Set the signal Valuetable:

Signal Attribute interpretation ：

1. Factor and Offset Defined raw value And physical value The relationship between .

raw value yes CAN The message is sent to Hexadecimal data on the bus ,
physical value Is the value of the physical quantity represented by the signal , for example , The speed of the car 、 speed 、 Temperature etc. .
Init.Value、Minimum and Maximum Are all physical value.
raw value And physical value And Between the The relationship is ：
physical value=([raw value]×[Factor])+[Offset].

2. Byte Order

Signals in the database Byte Order（ Byte order ） It is divided into Motorola and Intel Two data formats （ Also known as big End mode and small end mode ）, The byte order of the two formats is as follows .

3. Value Table

Value Table（ Numerical table ） It is used to specify the meaning represented by the value of signal or environment variable in writing , for example , The signal created earlier OnOff,0 representative Off state ,1 representative On state .

signal and Environment Variables All have this property .

environment variable Environment Variables

Environment Variable（ environment variable ） yes ECU、 Panels and CAPL The media through which programs are connected .

for example , stay CAPL In the program , Specific actions can be triggered by changing or monitoring the value of an environment variable , Again , Environmental change The value of the quantity can also be associated with the control control or display control on the panel .

Compared with system variables , Environment variables are only used in CANdb++ In the definition of . This example uses DBC Templates , Two environment variables will be automatically created EnvKlemmel5 and EnvKlemme30, You can delete it directly if you don't need it .

Environment variable configuration

X-Vehicle-1 There is 1 Environment variables EnvDoorState. Configure as shown below

Description of the meaning of environment variable attributes ：

Environment variable ValueTabe To configure

EnvDoorState Of valueTable Configuration values

Name: VtEnv_Door_Status
Value Description:
- 0: BothDoorClose:
- 1: LeftDoorOpen:
- 2: RightDoorOpen:
- 3: BothDoorOpen

operation -1: To configure ValueTable

operation -2 Set up EnvDoorState Of ValueTable

Consistency check

If it passes the consistency test , No alarm or error , Then the design of the database is completed .

5. Database engineering XVehicle.dbc Import project file

CAN After database creation , You can import it into the created project file . This will be described below XVehicle1 The database imports the previously created X-Vehicle-1 In the project .

stay Simulation Setup In the system view of , Right click Database choice Import Wizard command , In the pop-up Select... In the dialog box XVehicle database , And the nodes Display、Door and Engine Add to Assigned nodes in , Pictured 8.24 Shown .