This package provides a lightweight java wrapper around SOEM (https://github.com/OpenEtherCATsociety/SOEM) and provides an Object Orientated interface to the EtherCAT master.
Extra functionality built on top of SOEM includes
- Automatic configuration of PDO's
- EtherCAT slave state management
- Thread synchronization with DC Master Clock
- Linux (Ubuntu 20.04+ or similar x86_64, arm64)
Requires Java 17.
Add the IHMC EtherCAT Master as dependency
dependencies {
implementation group: 'us.ihmc', name: 'ihmc-ethercat-master', version: '0.15.0'
}
Example code is provided in us.ihmc.etherCAT.examples.
All conforming EtherCAT slaves should work with this wrapper. Slave code has been provided for several devices, including
- Beckhoff EK1100
- Beckhoff EL3314
- Beckhoff EL4134
- Elmo Twitter
General slave code provided
- DSP402 statemachine
Custom slave code is straightforward to implement based on provided slave examples.
To show the slaves available on the bus the provided class us.ihmc.etherCAT.master.SlaveInfo can be used.
Copyright 2021 Florida Institute for Human and Machine Cognition (IHMC)
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.
This library is split up in two parts, the C library with SWIG wrapper and the actual Java library. They need to be compiled independently. SOEM needs to be compiled with position independent code enabled, otherwise a shared JNI library cannot be build.
The Halodi Robotics PPA has a debian package of SOEM that is compatible with this library. Install it using
sudo add-apt-repository ppa:halodirobotics/ppa
sudo apt update
sudo apt install soem
Clone SOEM from https://github.com/OpenEtherCATsociety/SOEM
Optionally, use switch to the same version as used to compile the maven libraries
cd SOEMgit checkout v1.4.0
Note that in order to build a shared JNI library, you have to enable position independent code for SOEM. Use the following commands to build and install the SOEM library
cd SOEM
mkdir build
cd build
cmake -DHOST_INSTALL="" -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_POSITION_INDEPENDENT_CODE=true -DCMAKE_BUILD_TYPE=Release ..
make
make install
- CMake
- OpenJDK 8
- Swig 3.0.8 or higher.
A gradle wrapper is provided, optionally you can use your system gradle by replacing "./gradlew" with gradle.
The gradle build files for the SOEM wrapper and native libraries are created by cmake, based on the input files in swig/build.gradle.kts.in and swig/settings.gradle.kts.in. After running cmake and make, the gradle build is exectud from the build directory. This is done to split the GPL+linking exception licenced SOEM from the Apache 2.0 licensed IHMC-ethercat-master.
To build and publish run the following commands. Note that the gradle commands are ran from within the build directory.
cd ihmc-ethercat-master
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
# Cross compile for arm64 using the toolchain
# cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=../linux-aarch64-toolchain.cmake ..
make
../gradlew publishToMavenLocal -Ptarget=JAVA
../gradlew publishToMavenLocal -Ptarget=PLATFORM
Note that if you want to publish multiple platform libraries you only have to run target=JAVA on a single platform
- cd ihmc-ethercat-master
- ./gradlew publishToMavenLocal
Build the docker images first with: ./buildDockerImages.sh
Then run: ./buildWithDocker.sh to build the artifacts, they will be copied to the host's local maven repository.