CLEARPATH Turtlebot4 User Manual page 105

void button_1_function()
{
// Create a ROS2 message
auto lightring_msg = irobot_create_msgs::msg::LightringLeds();
// Stamp the message with the current time
lightring_msg.header.stamp = this->get_clock()->now();
// Override system lights
lightring_msg.override_system = true;
// LED 0
lightring_msg.leds[0].red = 255;
lightring_msg.leds[0].blue = 0;
lightring_msg.leds[0].green = 0;
// LED 1
lightring_msg.leds[1].red = 0;
lightring_msg.leds[1].blue = 255;
lightring_msg.leds[1].green = 0;
// LED 2
lightring_msg.leds[2].red = 0;
lightring_msg.leds[2].blue = 0;
lightring_msg.leds[2].green = 255;
// LED 3
lightring_msg.leds[3].red = 255;
lightring_msg.leds[3].blue = 255;
lightring_msg.leds[3].green = 0;
// LED 4
lightring_msg.leds[4].red = 255;
lightring_msg.leds[4].blue = 0;
lightring_msg.leds[4].green = 255;
// LED 5
lightring_msg.leds[5].red = 0;
lightring_msg.leds[5].blue = 255;
lightring_msg.leds[5].green = 255;
// Publish the message
lightring_publisher_->publish(lightring_msg);
}