led_strip_hmi_embedded

Micro-ROS application for controlling LED strips as an embedded HMI on the Arduino Portenta H7.

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Hardware

• MCU: Arduino Portenta H7 (STM32H747 MCU)
  Portenta H7 documentation
• Baseboard: Arduino Portenta Hat Carrier
  Portenta Hat documentation
• LED Strip: Adafruit NeoPixel
  NeoPixel LED strip
• Programmer: ST-Link V2
  ST-Link V2 documentation

Note:
The NeoPixel LED strip requires a 5V power supply. The Portenta H7 provides 3.3V on SPI pins, which may not be sufficient for reliable operation. Use a level shifter or a separate 5V supply for the NeoPixel strip.

SPI Pinout (Portenta Hat J5):

• Pin 19 (SPI1_MOSI) - Data line for NeoPixel
• Pin 23 (SPI1_SCK) - Clock line for NeoPixel

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Software

This project is built using the Zephyr RTOS and micro-ROS framework.

• Zephyr RTOS
• micro-ROS

For setting up micro-ROS on Zephyr, we build upon the micro-ros-zephyr-module repository micro-ros-zephyr-module.

Setup

1. ROS Communication

The micro-ROS framework is used to communicate with a ROS 2 system over Ethernet (UDP/IP).
The micro-ros-agent bridges the embedded application and the ROS 2 system.

Start the agent:

docker run -it --rm -v /dev:/dev --privileged --net=host microros/micro-ros-agent:jazzy udp4 --port 8888 -v6

The host machine should be configured with IP address 10.42.0.1.

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2. Building and Flashing

Prerequisites:

• Zephyr SDK and toolchain
• Python 3.x
• STM32CubeProgrammer (for flashing)
• West (Zephyr meta-tool)

Initialize workspace (if not already done):

west init -l .
west update
pip install -r zephyr/scripts/requirements.txt

Configure udev rules for ST-Link (Linux):

# Copy rules from CubeProgrammer Drivers/rules to /etc/udev/rules.d/
sudo udevadm control --reload-rules
sudo udevadm trigger

Build the firmware:

west build -d build_caripu_app -b arduino_portenta_h7_m7 applications/caripu

Flash the firmware (using ST-Link):

west flash -d build_caripu_app

or use STM32CubeProgrammer GUI/CLI.