Hi, welcome to Robotis :)
If you are new to Dynamixel, it might be a bit difficult to use Dynamixel on ROS.
This is because you need to get familiar with Control Table and Protocol for Dynamixel first.
Depending on your Dynamixel, there are Protocol 1.0 and Protocol 2.0.
I'd recommend to go over the eManual first.
- Protocol 1.0 : http://emanual.robotis.com/docs/en/dxl/protocol1/
- Protocol 2.0 : http://emanual.robotis.com/docs/en/dxl/protocol2/
Dynamixel as a smart servo, has a Control Table which allows user to read and write various parameters to control Dynamixel.
Each product may have different Control Table so please read carefully regarding your Dynamixel.
Below is the eManual link for one of the most popular products.
Once you understand the basic of Dynamixel, you can start playing with Arduino examples for OpenCM9.04.
If you complete setting up the Arduino IDE, there are various examples you can play with.
However, some of the examples may require little bit of modification such as Control Table Addresses or valid data range values.
When you are familiar with basic control of Dynamixel, you are ready for DynamixelSDK which is used in ROS.
Please feel free to use this forum to ask any questions.
You can also search for many previous questions if you search for OpenCM 9.04 in the forum.