OpenCM compatibility

Use the following template to help create your post:

  1. What model(s) of servo are you using?
    xl330-m077-t, XM430-W210-T

  2. Describe your control environment. Include the controller or interface, operating system (and version #) of your computer, and how you are powering your robot.

OpenCM 9.04 C-type

  1. For programming posts, state any libraries or example code you are using. For software posts, be clear about which version of software! R+ Task 3.0, R+ Task 2.0, and RoboPlus Task (“1.0”) can have very different troubleshooting steps, as just one example.

  2. Remember to mark your post Solved when applicable!

Hello, I am trying to control XL330-M077-T and XM430-W210-T together with an OpenCM 9.04 board. I will power both motors with separate power sources and try to connect them using TTL communication. Here are my questions:

  1. Can the OpenCM board control XL and XM motors without an expansion board?

  2. Is it better to use an Arduino MKR + Dynamixel Shield?

  3. Is OPENRB-150 the board can substitute Arduino MKR + Dynamixel Shield? Do I need a OPENRB-150 board only to control both XL330-M077-T and XM430-W210-T motors together?

  4. Does OPENRB-150 have Bluetooth connectivity?

  5. What is difference between OpenCM board and OPENRB-150 board?

  1. The OpenCM is designed to operate only XL320 servos without an expansion board. It is not recommended to operate other DYNAMIXEL servos with the OpenCM without the expansion board.
  2. An Arduino MKR and MKR Shield offer additional flexibility compared to the OpenCM, but which board is better will depend on your specific project requirements.
  3. The OpenRB can be used to control DYNAMIXEL servos without any additional external components. I must advise you however, that the XL330-M077-T and XM430-W210-T operate on different input voltages, and cannot be used on the same circuit without special considerations.
  4. Not internally, but it is compatible with all Arduino MKR format shields, so you can add additional features as needed.
  5. The OpenRB is our newest most feature complete Arduino based board, it can be considered a direct upgrade from the OpenCM.


This is one possible setup for using OpenCM-904 with a group of XL-330s and XL-430s:

  1. I chose to power my OpenCM-904 and two XL-330s at 5 V: standard setup but notice that a special cable is needed between OpenCM-04 and XL-330s.

This is called an “XL-320 Convertible” cable - see this link

Unfortunately, it is currently out of stock.

  1. The XL-430s are on 12 V of course >>also standard setup:

  1. The KEY component is the 3P-XL cable connecting the 330s to the 430s whereas their different operating voltages need to be isolated from each other (i.e., VDD Line). So VDD Line needs to be severed, while keeping the GROUND and DATA Lines INTACT.

Then I used ARDUINO to check that this hybrid system is doing what it is supposed to do:

Best Wishes for your project!