Objects of Communication matrix

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Objects of Communication matrix

 

Control units

(ECUs, nodes)


ECUs are electronic modules in motor vehicles, which independently accept, process and forward information. ECUs have defined control tasks, e.g. for the engine, the display instruments, the light system or the airbags.

 

 

Message

(telegram, frame)


A message is a bundle of information units, which is sent from one control unit on the CAN bus. It can either send cyclical status information (e.g. the temperature) or transmit event-triggered information (e.g. the defect of a lamp). All messages have a unique identifier.

 

 

Multiplex message


A multiplex message contains different signals depending on the mode signal. The value of the mode signal refers to one or more included signals. This way, the limited amount of message IDs on the CAN data line can be used several times.

 

 

Signal


A signal is a specific information unit within a message. A message about the safety belt lock can, for example, contain several signals on all safety belt lock positions transmitted.

 

Attribute


Attributes define additional information of an object in the communication matrix, describing it in detail or determining its dimensioning (e.g. cycle time).

 

 

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