CANopenNode is free and open source CANopen Stack.
CANopen is the internationally standardized (EN 50325-4) (CiA301) CAN-based higher-layer protocol for embedded control system. For more information on CANopen see http://www.can-cia.org/
CANopenNode is written in ANSI C in object-oriented way. It runs on different microcontrollers, as standalone application or with RTOS. Stack includes master functionalities. For Linux implementation with CANopen master functionalities see https://github.com/CANopenNode/CANopenSocket.
Variables (communication, device, custom) are ordered in CANopen Object Dictionary and are accessible from both: C code and from CAN network.
CANopenNode homepage is https://github.com/CANopenNode/CANopenNode
RTR (remote transmission request) is a feature of CAN bus. Usage of RTR is not recommended for CANopen and it is not implemented in CANopenNode.
Object 0x1F80 from Object Dictionary enables the NMT slaves to start automatically or allows it to start the whole network. It is specified in DSP302-2 standard. Standard allows two values for slaves for object 0x1F80:
Note: When node is stated (in NMT operational state), it is allowed to send or receive Process Data Objects (PDO). If Error Register (object 0x1001) is set, then NMT operational state is not allowed.
CANopenNode itself doesn't have complete working code for any microcontroller. It is only the library with the stack It has example, which should compile on any system with template driver (drvTemplate), which actually doesn't access CAN hardware. CANopenNode should be used as a git submodule included in a project with specific hardware and specific application.
Code is documented in header files. Running doxygen
or make doc
in project base folder will produce complete html documentation.
Just open CANopenNode/doc/html/index.html in browser.
Report issues on https://github.com/CANopenNode/CANopenNode/issues
Older and still active discussion group is on Sourceforge http://sourceforge.net/p/canopennode/discussion/387151/
For some implementations of CANopenNode on real hardware see Device support section. CANopenSocket is nice implementation for Linux devices. It includes command line interface for master access of the CANopen network. There is also some Getting started.
Contributions are welcome. Best way to contribute your code is to fork
a project, modify it and then send a pull request. Some basic formatting
rules should be followed: Linux style with indentation of 4 spaces. There
is also a configuration file for clang-format
tool.
-----------------------
| Program start |
-----------------------
|
-----------------------
| CANopen init |
-----------------------
|
-----------------------
| Start threads |
-----------------------
| | |
-------------------- | --------------------
| | |
----------------------- ----------------------- -----------------------
| CAN receive thread | | Timer interval thread | | Mainline thread |
| | | | | |
| - Fast response. | | - Realtime thread with| | - Processing of time |
| - Detect CAN ID. | | constant interval, | | consuming tasks |
| - Partially process | | typically 1ms. | | in CANopen objects: |
| messages and copy | | - Network synchronized| | - SDO server, |
| data to target | | - Copy inputs (RPDOs, | | - Emergency, |
| CANopen objects. | | HW) to Object Dict. | | - Network state, |
| | | - May call application| | - Heartbeat. |
| | | for some processing.| | - May cyclically call |
| | | - Copy variables from | | application code. |
| | | Object Dictionary to| | |
| | | outputs (TPDOs, HW).| | |
----------------------- ----------------------- -----------------------
-----------------------
| SDO client (optional) |
| |
| - Can be called by |
| external application|
| - Can read or write |
| any variable from |
| Object Dictionary |
| from any node in the|
| CANopen network. |
-----------------------
-----------------------
| LSS client (optional) |
| |
| - Can be called by |
| external application|
| - Can do LSS requests |
| - Can request node |
| enumeration |
-----------------------
Object Dictionary is one of the most important parts of CANopen. Its implementation in CANopenNode is quite outdated and there are efforts to rewrite it. Anyway, currently it is fully operational and works well.
To customize the Object Dictionary it is necessary to use the external application. There are two:
CANopenNode can be implemented on many different devices. It is necessary to implement interface to specific hardware, so called 'driver'. Currently driver files are part of CANopenNode, but they will be split from it in the future.
Most up to date information on device support can be found on CANopenNode/wiki.
For the driver developers, who wish to share and cooperate, I recommend the following approach:
git submodule add https://github.com/CANopenNode/CANopenNode
Project was initially hosted on http://sourceforge.net/projects/canopennode/ It started in 2004 with PIC18F microcontrollers from Microchip. Fresh, cleaned repository of CANopenNode stack started on 25.7.2015. For older history see http://sourceforge.net/p/canopennode/code_complete/
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
此处可能存在不合适展示的内容,页面不予展示。您可通过相关编辑功能自查并修改。
如您确认内容无涉及 不当用语 / 纯广告导流 / 暴力 / 低俗色情 / 侵权 / 盗版 / 虚假 / 无价值内容或违法国家有关法律法规的内容,可点击提交进行申诉,我们将尽快为您处理。