DFROBOT Dynamixel SPI with Python

This is a Python library for controlling DFRobot's Dynamixel motors using SPI communication.

Requirements

• Raspberry Pi 4B or 5B
• Python 3.7 or higher
• DFROBOT Digital Servo Shield for Dynamixel AX
• Dynamixel AX-12A
• 12V power supply

Wiring

Pin Type	DFROBOT servo driver	Raspberry Pi 4 or 5B
VCC (POWER)	VCC	N/A
GND (POWER)	GND	N/A
5V	5V	5V
GND	GND	GND
SCK	GPIO13	GPIO11
MISO	GPIO12	GPIO9
MOSI	GPIO11	GPIO10
CS	GPIO10	GPIO8

Setup

1. Create a virtual environment:

   python -m venv venv

2. Activate the virtual environment:

   source venv/bin/activate

3. Activate I2C, SPI, Serial and Camera interfaces:

   sudo raspi-config nonint do_i2c 0
   sudo raspi-config nonint do_spi 0
   sudo raspi-config nonint do_serial_hw 0
   sudo raspi-config nonint do_ssh 0
   sudo raspi-config nonint do_camera 0
   sudo raspi-config nonint disable_raspi_config_at_boot 0

4. Enable dtoverlay for spi0-0cs

   sudo nano /boot/firmware/config.txt

   Add the following line at the end of the file:

   dtoverlay=spi0-0cs
   

5. Reboot the Raspberry Pi:

    sudo reboot

6. Activate the virtual environment again:

   source venv/bin/activate

7. Install Adafruit Blinka:

   sudo apt-get install -y i2c-tools libgpiod-dev python3-libgpiod
   pip install --upgrade pip
   pip install --upgrade RPi.GPIO
   pip install --upgrade adafruit-blinka

8. (Optional for RPI5) Delete rpi.gpio and install rpi-lpgpio:

   sudo apt remove -y python3-rpi.gpio
   pip uninstall -y RPi.GPIO
   pip install --upgrade rpi-lgpio

9. Execute servo_test.py to test the servo:

   python3 servo_test.py