Manual

I2C Interface
The linux I2C drivers are used to read and write data on the I2C buses of the Raspberry Pi. The
display's SSD1306 driver is connected to the i2c-3 device by default, but other buses are
available too.
SSD1306
The SSD1306 is a driver for OLED displays. It receives commands over a communication bus
(I2C for the TurtleBot 4) and controls how the physical display behaves. The TurtleBot 4 uses a
modified version of this STM32 SSD1306 driver to write pixels, shapes and characters to the
display.
Configuration
Warning
Do NOT change pin definitions if you are using the standard PCBA or do not know what you are
doing.
The turtlebot4_base_node pin definitions can be set with ROS parameters. The default
configuration is:
turtlebot4_base_node:
ros__parameters:
# GPIO definition for HMI. Do NOT change if you are using the standard PCBA.
gpio:
user_button_1: 13
user_button_2: 19
user_button_3: 16
user_button_4: 26
led_green_power: 17
led_green_motors: 18
led_green_comms: 27
led_green_wifi: 24
led_green_battery: 22
led_red_battery: 23
led_green_user_1: 25
led_green_user_2: 6
led_red_user_2: 12
display_reset: 2