[et_pb_section fb_built=”1″ custom_padding_last_edited=”off|desktop” admin_label=”Header” _builder_version=”4.17.3″ background_color_gradient_direction=”176deg” background_image=”https:\/\/www.microcontrol.net\/wp-content\/uploads\/2021\/10\/MicoControl_Grundlagen_CANopen.png” width=”90%” custom_margin=”||||false|false” custom_margin_tablet=”||||false|false” custom_margin_phone=”||||false|false” custom_margin_last_edited=”off|phone” custom_padding=”|0px||10vw|false|false” custom_padding_tablet=”||||false|true” background_last_edited=”on|phone” parallax_phone=”off” parallax_method_phone=”off” background_size_phone=”cover” background_position_tablet=”bottom_center” background_position_phone=”bottom_center” custom_css_before=”content:%22%22;|| display: block;|| position: absolute;|| top: 0;|| left: 0;|| width: 100%;|| height: 100%;||background: rgb(0,0,0);||background: linear-gradient(160deg, rgba(0,0,0,0.3) 20%, rgba(255,255,255,0) 50%);|| z-index: 2;” locked=”off” global_colors_info=”{}” custom_css_before_last_edited=”off|desktop” custom_css_before_phone=”content:%22%22;|| display: block;|| position: absolute;|| top: 0;|| left: 0;|| width: 100%;|| height: 100%;||background: rgb(0,0,0);||background: linear-gradient(160deg, rgba(0,0,0,0.3) 20%, rgba(255,255,255,0) 50%);|| z-index: 2;”][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” width=”100%” custom_margin=”|0px|0px||false|false” custom_padding=”||||false|false” global_colors_info=”{}”][et_pb_column type=”1_2″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.microcontrol.net\/wp-content\/uploads\/2021\/08\/MicroControl-Troisdorf-Germany.png” title_text=”MicroControl Troisdorf Germany” show_bottom_space=”off” align=”right” _builder_version=”4.16″ _module_preset=”default” background_enable_image=”off” background_size=”contain” background_position=”bottom_right” module_alignment=”right” custom_margin=”|0px||0px|false|false” custom_padding=”|0px||0px|false|false” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_margin=”|auto|-1px|auto||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][lwp_divi_breadcrumbs use_before_icon=”off” link_color=”#ef7c00″ separator_color=”#565655″ current_text_color=”#565655″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][\/lwp_divi_breadcrumbs][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” collapsed=”off” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_padding=”||5px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ header_font=”|600|||||||” header_text_color=”#565655″ header_font_size=”36px” header_line_height=”1.1em” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”36px” background_layout=”dark” custom_margin=”||||false|false” custom_padding=”||||false|false” header_font_size_tablet=”48px” header_font_size_phone=”28px” header_font_size_last_edited=”on|desktop” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”||||false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]CANopen is an open communication protocol based on the CAN bus and is used in many areas of automation. On this page, you will find an easy-to-understand introduction to CANopen \u2013 from the most important fundamentals and core concepts through to typical practical applications. This article is aimed at engineers and students who want to gain a solid understanding of CANopen and use it in their projects.[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”||92px|||” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.22.0″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]CANopen is an open communication protocol based on the CAN bus and standardizes how controllers, sensors, and actuators exchange data with each other in distributed systems. In contrast to the plain CAN bus, the CANopen protocol not only describes the frame format on the wire, but also device profiles, configuration mechanisms, and diagnostic functions. This makes devices from different manufacturers compatible with each other in many applications and easier to integrate.[\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n
CANopen is used wherever robust, real-time capable communication between multiple control units is required. Typical application areas include: <\/p>\n
The combination of simple wiring, high noise immunity, and standardized device profiles makes CANopen particularly attractive for embedded systems. Developers benefit from the fact that many basic functions \u2013 such as the exchange of process data, parameter configuration, or error detection \u2013 are already defined by the protocol. <\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n
[\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n
The CAN bus (Controller Area Network) is a serial fieldbus system that was originally developed for use in vehicles. It defines, among other things: <\/p>\n
CAN itself therefore describes how<\/strong> bits are placed on the bus and how multiple nodes communicate in a collision-free and fault-tolerant manner. What the individual frames actually mean is left open. Without an additional protocol layer, each project and each application would have to define for itself which identifiers carry which data and how parameters are to be interpreted. <\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n The CANopen protocol is built directly on this foundation. CANopen uses CAN frames as the transport medium and defines: <\/p>\n This raises the level of abstraction: instead of defining each device and each frame individually, standardized profiles and communication mechanisms are available. Developers no longer need to deal with every detail of the CAN frame, but work at the level of objects, parameters, and services provided by the CANopen stack. <\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n The OSI layer model helps to put things into context:<\/p>\n Put simply, CANopen takes on the role of the \u201clanguage\u201d that devices use to communicate over the CAN bus. It defines which data<\/strong> is transmitted with which meaning<\/strong>, how it is structured, and which services a CANopen node must support. For developers, this classification is important: hardware-related functions (transceiver, CAN controller) remain on the CAN level, while application logic and protocol behavior are implemented in the CANopen stack. <\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n A CANopen network consists of several nodes that are connected via the CAN bus. Each node has a unique node ID. Typically, one device in the network takes on the role of a CANopen manager (originally referred to as the master) \u2013 for example a central controller, PLC, or higher-level control unit. <\/p>\n Typical tasks of a CANopen manager include:<\/p>\n The remaining nodes act as devices (originally referred to as slaves). They provide their process data (e.g. measured values, setpoints) and can be configured via standardized objects. CANopen clearly defines which protocol behavior a compliant device must exhibit \u2013 regardless of the manufacturer. <\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]The heart of every CANopen node is the object dictionary. It represents all information of a device that is relevant for communication and configuration. The object dictionary describes the complete functional scope (parameters) of a CANopen device and is organized in tabular form. It contains not only the standardized data types and objects of the CANopen communication profile and the device profiles, but also, where applicable, manufacturer-specific objects and data types. The entries are addressed using a 16-bit index (row address of the table, up to 65,536 entries) and an 8-bit subindex (column address of the table, up to 256 entries). This makes it easy to group related objects. The structure of this CANopen object dictionary is shown in the following figure.[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row disabled_on=”off|off|off” _builder_version=”4.24.2″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.24.2″ _module_preset=”default” global_colors_info=”{}”][dvmd_table_maker tbl_title_mode=”on” tbl_title_text=”Structure object dictionary” tbl_title_position=”below” _builder_version=”4.27.4″ _module_preset=”default” tbl_title_level=”h5″ global_colors_info=”{}”][dvmd_table_maker_item col_label=”Index” col_content=” [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n The CANopen protocol provides various communication services that serve different purposes:<\/p>\n Together, these communication services form the \u201ctoolbox\u201d used to configure, monitor, and operate CANopen nodes in real-time operation.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”1_2″ _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n Every CANopen node follows a defined state machine. Typical states are: <\/p>\n <\/p>\n Transitions between these states are controlled by NMT commands. For developers, the state machine is important to define, for example, from which point in time process data is valid, when configuration is allowed, or how a controller brings a system step by step into operation after power-up. <\/p>\n [\/et_pb_text][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.microcontrol.net\/wp-content\/uploads\/2025\/11\/canopen-nmt-states.webp” alt=”CANopen NMT state machine” title_text=”canopen-nmt-states” _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]CANopen emerged in the early 1990s from the need to use the CAN bus not only as pure vehicle technology, but also in industrial automation. Many manufacturers were already using CAN, but each defined its own protocols and data formats \u2013 making it difficult or impossible to exchange devices from different vendors. <\/p>\n To improve this situation, the users\u2019 and manufacturers\u2019 organization CAN in Automation (CiA)<\/a><\/strong> was founded. The goal of CiA was to specify an open, cross-vendor protocol based on CAN. Out of this environment, CANopen evolved as a standardized application protocol with clearly defined device profiles. <\/p>\n Early on, the first specifications and implementations appeared in various industries, especially in mechanical engineering and mobile machinery. As CANopen became more widespread, the need for stable, standardized documents grew \u2013 forming the basis for later formal standardization.[\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n Over time, a number of documents related to CANopen have been created. The most important foundations are: <\/p>\n In addition, there is a wide range of other CiA documents, for example for device and application profiles (such as CiA 401, CiA 402). For developers, this means that depending on the application, specific profile standards are relevant in addition to the basic documents. <\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n Over the years, CANopen has evolved from a protocol for rather specialized applications into an established standard in industrial communication. Reasons for this include: <\/p>\n Even though many other communication systems exist today (e.g. Industrial Ethernet variants), CANopen remains an attractive solution in numerous applications \u2013 especially where:<\/p>\n With CANopen FD, the standard is also being adapted to modern requirements without abandoning the fundamental CANopen concept. For developers, this means that investments in CANopen know-how remain valuable in the long term, regardless of whether classic CAN or CAN FD is used. <\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” global_colors_info=”{}”][et_pb_row _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]CANopen is used in many industries. Typical examples include:<\/p>\n What all these applications have in common is that they involve distributed, embedded systems with multiple controllers, clear real-time requirements, and high demands on reliability \u2013 an ideal use case for CANopen.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n From a developer\u2019s perspective, CANopen offers a number of advantages:<\/p>\n Taken together, this makes CANopen an attractive option for many embedded projects where robust fieldbus communication is required.<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.16″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 0%|#ececec 100%” background_color_gradient_start=”#ffffff” background_color_gradient_end=”#ececec” custom_padding=”0px||30px||false|false” global_colors_info=”{}”][et_pb_row disabled_on=”off|off|off” _builder_version=”4.24.0″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” custom_margin=”34px|auto|0px|auto|false|false” custom_padding=”7px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n Based on the concepts described in this article, MicroControl offers modular CANopen \/ CANopen FD protocol stacks<\/a> that are specifically optimized for use in embedded systems. The stacks are designed for low memory footprint and high performance and can be flexibly ported to different target hardware platforms via the standardized CANpie FD driver interface. <\/p>\n [\/et_pb_text][et_pb_image src=”https:\/\/www.microcontrol.net\/wp-content\/uploads\/2024\/02\/Protokollstacks_CANopen_Lego_geschnitten.jpg” alt=”CANopen protocol stacks from MicroControl, symbol picture” title_text=”Protokollstacks_CANopen_Lego_geschnitten” url=”https:\/\/www.microcontrol.net\/en\/portfolio\/protocol-stacks\/canopen\/” url_new_window=”on” _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n CANopen \/ CANopen FD master protocol stack<\/a><\/strong> [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n CANopen \/ CANopen FD slave protocol stack<\/a><\/strong> [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n CANopen bootloader protocol stack<\/a><\/strong> [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]<\/p>\n In addition to the protocol stacks, MicroControl offers training, workshops, and technical consulting on CAN, CANopen, and CANopen FD.<\/p>\n This makes MicroControl not just a supplier of protocol software, but a full-service partner for CANopen projects \u2013 from the initial concept phase through implementation all the way to series support.<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ disabled_on=”off|off|off” _builder_version=”4.16″ _module_preset=”default” background_color=”#ef7c00″ custom_margin=”0px||0px||false|false” custom_padding=”48px||48px||false|false” global_colors_info=”{}”][et_pb_row use_custom_gutter=”on” gutter_width=”2″ _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” module_alignment=”center” custom_padding=”0px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.22.0″ _module_preset=”default” header_font=”||||||||” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” header_3_font=”||||||||” header_3_text_align=”left” header_3_text_color=”#ef7c00″ background_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”10px||0px|10px|false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” module_alignment=”center” custom_margin=”0px||||false|false” custom_padding=”0px|1px|0px||false|false” border_color_bottom=”RGBA(0,0,0,0)” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” background_color=”rgba(0,0,0,0.08)” border_width_bottom=”2px” border_color_bottom=”#FFFFFF” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_text_color=”#FFFFFF” custom_padding=”10px|15px|10px|10px|false|false” link_option_url=”https:\/\/files.microcontrol.net\/appnotes\/an1201.pdf” link_option_url_new_window=”on” hover_enabled=”0″ global_colors_info=”{}” sticky_enabled=”0″]<\/p>\n Application Note 1201 (english) – Introduction to CANopen<\/p>\n PDF [376 KB]<\/span><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.24.2″ _module_preset=”default” text_text_color=”#FFFFFF” custom_padding=”10px|15px|10px|10px|false|false” link_option_url=”https:\/\/files.microcontrol.net\/appnotes\/an1202.pdf” link_option_url_new_window=”on” border_color_all=”#FFFFFF” border_width_top=”1px” global_colors_info=”{}”]<\/p>\n Application Note 1202 (englisch) – Identifier Usage in CANopen Networks [\/et_pb_text][et_pb_text _builder_version=”4.22.0″ _module_preset=”default” text_text_color=”#FFFFFF” custom_padding=”10px|15px|10px|10px|false|false” link_option_url=”https:\/\/files.microcontrol.net\/appnotes\/an1203.pdf” link_option_url_new_window=”on” border_color_all=”#FFFFFF” border_width_top=”1px” global_colors_info=”{}”]<\/p>\n Application Note 1203 (englisch) – Automatic start of CANopen slave devices [\/et_pb_text][et_pb_text _builder_version=”4.24.2″ _module_preset=”default” text_text_color=”#FFFFFF” custom_padding=”10px|15px|10px|10px|false|false” link_option_url=”https:\/\/files.microcontrol.net\/appnotes\/an1204.pdf” link_option_url_new_window=”on” border_color_all=”#FFFFFF” border_width_top=”1px” global_colors_info=”{}”]<\/p>\n Application Note 1204 (englisch) – Configuration of CANopen devices via LSS [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ disabled_on=”off|off|off” _builder_version=”4.16″ _module_preset=”default” background_color=”#ef7c00″ custom_margin=”0px||0px||false|false” custom_padding=”48px||48px||false|false” global_colors_info=”{}”][et_pb_row use_custom_gutter=”on” gutter_width=”2″ _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” module_alignment=”center” custom_padding=”0px||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.16″ _module_preset=”default” header_font=”||||||||” header_3_font=”||||||||” header_3_text_align=”left” header_3_text_color=”#ef7c00″ background_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”10px||0px|10px|false|false” global_colors_info=”{}”]<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”2_5,3_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ _module_preset=”default” background_color=”RGBA(0,0,0,0)” module_alignment=”center” custom_margin=”0px||||false|false” custom_padding=”0px|1px|0px||false|false” border_color_bottom=”RGBA(0,0,0,0)” global_colors_info=”{}”][et_pb_column type=”2_5″ _builder_version=”4.16″ _module_preset=”default” background_color=”rgba(0,0,0,0.08)” border_width_bottom=”2px” border_color_bottom=”#FFFFFF” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.microcontrol.net\/wp-content\/uploads\/2021\/08\/MicroControl_Produktanfrage.jpg” title_text=”MicroControl_Product inquiry” align=”center” force_fullwidth=”on” _builder_version=”4.16″ _module_preset=”default” background_enable_image=”off” background_size=”initial” module_alignment=”center” custom_margin=”||0px||false|false” custom_padding=”|0px||0px|false|false” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][et_pb_column type=”3_5″ _builder_version=”4.16″ _module_preset=”default” background_color=”rgba(0,0,0,0.08)” border_width_bottom=”2px” border_color_bottom=”#FFFFFF” global_colors_info=”{}”][et_pb_cta title=”+49 2241 – 25 65 9 – 0″ button_url=”mailto:sales.int@microcontrol.net?subject=Request%20training” button_text=”Message” _builder_version=”4.23.4″ _module_preset=”default” header_level=”h3″ header_font=”|700|||||||” header_text_color=”#FFFFFF” body_text_color=”#3a3a3a” body_font_size=”16px” body_line_height=”1.6em” background_color=”RGBA(0,0,0,0)” custom_button=”on” button_text_size=”20px” button_text_color=”#ef7c00″ button_bg_color=”#FFFFFF” button_border_width=”0px” button_border_color=”#FFFFFF” button_border_radius=”6px” button_letter_spacing=”1px” button_alignment=”center” button_custom_padding=”||||false|false” custom_margin=”0px||||false|false” custom_padding=”30px||30px||false|false” border_color_top=”#FFFFFF” border_color_bottom=”#FFFFFF” global_colors_info=”{}”]<\/p>\n Write an email or give us a call.<\/p>\n [\/et_pb_cta][\/et_pb_column][\/et_pb_row][\/et_pb_section]<\/p>\n","protected":false},"excerpt":{"rendered":"How does CANopen build on CAN?<\/h3>\n
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CANopen in the OSI layer model<\/h3>\n
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Architecture and core concepts of CANopen<\/h2>\n
The CANopen network model<\/h3>\n
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Object dictionary<\/h3>\n
\n0000h<\/sub>
\n0001h<\/sub> – 009Fh<\/sub>
\n00A0h<\/sub> – 0FFFh<\/sub>
\n1000h<\/sub> – 1FFFh<\/sub>
\n2000h<\/sub> – 5FFFh<\/sub>
\n6000h<\/sub> – 9FFFh<\/sub>
\nA000h<\/sub> – AFFFh<\/sub>
\nB000h<\/sub> – FFFFh<\/sub>” col_column_max_width=”0fr” col_column_min_width=”200px” _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][\/dvmd_table_maker_item][dvmd_table_maker_item col_label=”Objekt” col_content=”Objekt
\nreserved
\nData types
\nreserved
\nCommunication profile (CiA 301, CiA 1301, CiA 302)
\nManufacturer specific objects
\nObjects defined by device\/application profile (CiA 4xx)
\nNetwork variables (CiA 302-4)
\nreserved” _builder_version=”4.27.4″ _module_preset=”default” global_colors_info=”{}”][\/dvmd_table_maker_item][\/dvmd_table_maker][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.16″ _module_preset=”default” custom_padding=”0px||0px|||” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ _module_preset=”default” global_colors_info=”{}”][et_pb_text disabled_on=”off|off|off” _builder_version=”4.27.4″ _module_preset=”default” text_font=”|300|||||||” text_text_color=”#565655″ text_font_size=”17px” text_line_height=”1.4em” custom_margin=”||50px|||” custom_padding=”0px||||false|false” global_colors_info=”{}”]For developers, this means that a CANopen device can be queried and configured using a uniform scheme without needing to know its internal implementation.[\/et_pb_text][et_pb_text _builder_version=”4.27.4″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#ef7c00″ text_font_size=”24px” header_2_font=”|600|||||||” header_2_text_color=”#ef7c00″ header_2_font_size=”24px” custom_margin=”||14px||false|false” global_colors_info=”{}”]<\/p>\nCommunication services: SDO, PDO, NMT, SYNC, EMCY, Heartbeat<\/h3>\n
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SDOs are used for configuration and targeted data exchange with the object dictionary. Using SDO, a master can, for example, write parameter values or read status information. SDO communication is flexible but comparatively slow and not intended for hard real-time. <\/li>\n
PDOs are used for fast, cyclic exchange of process data. Typically, measurement values, status bits, or setpoints are transmitted in PDOs. A PDO can bundle several signals and is sent without additional protocol overhead \u2013 ideal for time-critical applications. <\/li>\n
NMT commands control the state of a node (e.g. Start, Stop, Pre-Operational, Reset). With these commands, the NMT master can bring the entire network into operation or stop it in a controlled way. <\/li>\n
The SYNC object is a special frame that serves as a synchronization pulse for the network. Nodes can link their PDO transmission to the reception of SYNC messages, enabling time-deterministic behavior. <\/li>\n
EMCY messages signal error conditions of a node. They are sent with high priority as soon as a defined error occurs and allow the higher-level controller to react quickly. <\/li>\n
Via heartbeat mechanisms, nodes periodically indicate that they are still active and in the expected state. This allows the manager to detect failed or blocked nodes at an early stage. <\/li>\n<\/ul>\nState machine \/ device states<\/h3>\n
\n
History and standardization<\/h2>\n
Origin of CAN in Automation<\/h3>\n
Key CANopen standards<\/h3>\n
\n
This document describes the fundamental structure of the CANopen protocol: communication objects, object dictionary, state machine, addressing, and the behavior of a CANopen-compliant device. CiA 301 is, so to speak, the \u201cheart\u201d of classic CANopen. <\/li>\n
With the introduction of CAN FD (Flexible Data-Rate), CANopen was extended as well: CANopen FD takes advantage of the extended capabilities of CAN FD, such as higher data rates and larger payloads. CiA 1301 defines how the CANopen concept is mapped onto CAN FD and which new options this enables. <\/li>\n<\/ul>\nDevelopment and current relevance<\/h3>\n
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Typical application areas and advantages<\/b><\/h2>\n
Industries and applications<\/b><\/h3>\n
\n
\nPackaging machines, assembly systems, handling and conveyor technology frequently rely on CANopen. Sensors, drives, I\/O modules, and operator panels are connected via a common network and managed by a central controller.<\/li>\n
\nAgricultural machinery, municipal vehicles, construction machinery, or special-purpose vehicles use CANopen to network control units, engine controllers, joysticks, display units, and safety systems.<\/li>\n
\nServo drives, stepper motors, and frequency inverters are often integrated using the CANopen drive profile (CiA 402). This allows motion sequences to be addressed in a standardized way and drives from different manufacturers to be combined within one system.<\/li>\n
\nIn medical devices, laboratory automation, or analysis systems, CANopen connects, for example, pumps, sensors, actuators, and operator interfaces. The requirements for reliability and diagnostic capabilities are particularly high in this field.<\/li>\n
\nIn rail vehicles, elevators, door systems, heating and ventilation systems, or energy installations, CANopen enables robust communication even in harsh environments and over long product life cycles.<\/li>\n<\/ul>\nTechnical advantages of CANopen<\/b><\/h3>\n
\n
With profiles such as CiA 401 (I\/O modules) and CiA 402 (drives), devices from different manufacturers behave largely the same. This simplifies the integration of new components and their replacement in the field. <\/li>\n
All relevant parameters of a device are accessible via the object dictionary. Instead of proprietary configuration protocols, there is a uniform scheme for reading and writing parameters. <\/li>\n
The combination of PDOs for fast process data and SDOs for configuration provides a good balance between real-time capability and flexibility. Developers can precisely define which signals are transmitted in which PDOs. <\/li>\n
Mechanisms such as EMCY (error messages) and heartbeat ensure that errors can be detected and handled in a targeted manner. Failed nodes can be identified quickly. <\/li>\n
Once implemented, CANopen functionality (e.g. a drive profile) can be reused in many projects. This reduces development effort and testing costs. <\/li>\n
CANopen builds on the proven CAN bus. Many microcontrollers already include integrated CAN controllers, and the physical interface is comparatively inexpensive. <\/li>\n<\/ul>\nCANopen solutions from MicroControl<\/h2>\n
CANopen protocol stacks <\/b><\/h3>\n
The CANopen master protocol stack forms the basis for complex controllers and the monitoring of complete CANopen networks. It supports, among others, the standards CiA 301 \/ CiA 1301 (FD), CiA 302, and CiA 305 and provides all essential services: SDO (client\/server), PDO, NMT, EMCY, SYNC, as well as Layer Setting Services (LSS). The number of PDOs, SDO clients, and even the number of supported CAN channels can be configured at runtime to optimally adapt RAM and flash usage to the target application. <\/p>\n
The CANopen slave protocol stack is designed for intelligent sensors and actuators and is optimized for particularly low resource requirements. It implements the full functionality of the CANopen standards CiA 301 \/ CiA 1301 and CiA 305 and is therefore ideal for compact devices with limited memory and simple controllers. <\/p>\n
For firmware updates via the CANopen network, MicroControl offers a CANopen bootloader protocol stack. It supports a reduced object dictionary scope as well as NMT, SDO (including block transfer), EMCY, heartbeat, and LSS, and enables the management of up to four flash memory areas for program and data. Updates are conveniently performed using the CANopen Download Tool, which is supplied as PC software. <\/p>\nTraining, workshops, and engineering support<\/b><\/h3>\n
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Downloads<\/h2>\n
How CAN identifiers are used in CANopen networks
PDF [118 KB]<\/span><\/p>\n
Configuration of cyclic PDO transmission and auto start function
PDF [291 KB]<\/span><\/p>\n
Configuration of bit rate and node-ID via Layer-Setting-Services
PDF [208 KB]<\/span><\/p>\nYou would like to get more information?<\/h3>\n