Schneider Electric DS301 manual Basics, CANopen technology, CANopen description language

IL•1F CANopen DS301 3 Basics

0198441113586, V2.01, 11.2008

3 Basics

3.1CANopen technology

3.1.1CANopen description language

CANopen is a device- and manufacturer-independent description lan- guage for communication via the CAN bus. CANopen provides a com- mon basis for interchanging commands and data between CAN bus devices.

3.1.2Communication layers

CANopen uses the CAN bus technology for data communication.

CANopen is based on the basic network services for data communica- tion as per the ISO-OSI model model. 3 layers enable data communica- tion via the CAN bus.

•Physical Layer

•Data Link Layer

•	Application Layer
	device communication
	application Layer
	data Link Layer
	physical Layer
	fielb bus communication
	CAN-Bus

Figure 3.1 CANopen layer model

Physical Layer The physical layer defines the electrical properties of the CAN bus such as connectors, cable length and cable properties such as bit-coding and bit-timing.

Data Link Layer The data link layer connects the network devices. It assigns priorities to individual data packets and monitors and corrects errors.

Application Layer The application layer uses communication objects (COB) to exchange data between the various devices. Communication objects are elemen- tary components for creating a CANopen application.

Fieldbus interface 15