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SEMA User Guide for GPIO with ADLNK Neuron AmITX-Motherboard

ADLINK demo gpio example ROS package:

Adlink-ROS/neuron_demo_gpio

This package is a demonstration of the integration of ROS2 and onboard GPIO control. It will provide ADLINK omni-NeuronBot peripheral sensor and visual indicators of robot state. The GPIO control is implemented with the ADLINK Smart Embedded Management Agent (SEMA) function, which comes with the Neuron AmITX-Motherboard. The SEMA features various board monitoring, failsafe, as well as GPIO and I2C functionality.

Getting Started

These instructions will get you a copy of this demo and running on your local machine.

Prerequisites

  1. Hardware and library
    You'll need the ADLINK SEMA library and a compatible motherboard to run this example. You can conatct bill.wang@adlinktech.com for more information.
  2. Download the source of this project to your ROS2 workspace
    cd ros2_ws/src/ros2 git clone https://github.com/EwingKang/neuron_demo_gpio.git
  3. 4 LEDs, 2 switches(one tactile, one contact)
  4. Your motherboard and GPIO connected

Installing

  1. Install ADLINK SEMA

  2. Setup soft link (by executing setlink.sh under /lib )
    Run the following command in the terminal command. If you get something like error: no such file as..., you'll need to make the setlink.sh executable by chmod +x setlink.sh. cd ${project_root}/lib e.g.: cd ros2_ws/src/ros2/neuron_demo_gpio/lib ./setlink.sh

  3. Compile the source code
    We'll need root access for library linking, that is done by the second step below; ROS2 uses ament as its default build/installation tool. cd ros2_ws sudo -sE ament build

Running the demo

Each of the code block below is a individual terminal with ROS2 environment veriable configured. ros2 run demo_nodes_cpp talker -t neuron_gpio_cmd root@neuron: ros2 run neuron_demo_gpio neuron_demo_gpio * root@neuron: ros2 run neuron_demo_gpio neuron_omni_io

NOTE1: terminal can gain root access by first doing sudo -sE NOTE2: alternatively, you can publish the triggering topic manually by run ros2 topic pub /neuron_hwm_cmd std_msgs/String "data: 0"

Monitoring

You can checkout the topics by:
ros2 topic list
and
ros2 topic echo /TOPIC

What should happened?

Besides the information you see on each terminal, proper ROS2 topic is published. neuron_demo_gpio node
Subscribes to topic neuron_gpio_cmd from talker
Publishes topic neuron_gpio_data of type std_msgs::String
 neuron_omni_io node
Subscribes to topic neuron_gpio_cmd from talker
Controls the LEDs and read from switches

Code explained

ANY kind of std_msgs data from TOPIC_CMD will trigger the node to publish the next hardware monitor data to TOPOC_DATA topic. 1. The setting of TOPIC_CMD and TOPIC_DATA can be found in reuronHwmNode.hpp

Notice

  1. This application MUST be running under SUDO -E since the SEMA driver need both root privilege and the user-exported variables.

Version

0.1.0

Authors

  • Alan Chen - Initial library - (alan.chen@adlinktech.com)
  • Ewing Kang - Demo implementation - (https://github.com/EwingKang)

License

This project is licensed under the Apache License, Version 2.0

Acknowledgments