Hello, is the open RB150 compatible with Dynamixel XL320 servos which are different from the XL series. Thank you for your response. Kind regards
OpenRB150 + L320 compatibility
You can use the XL-320 with the OpenRB-150. The XL-320 has Protocol 2, but its Control Table is different from the XL-330. Also the XL-320 operates at 7.5 V, and are you using other XL actuators in your robot?
See Section 2.5 of my Arduino Book for more details about proper usage of the Dynamixel2Arduino library with the XL-320.
The free Kindle sample of my book is accessible here
https://www.amazon.com/Using-ARDUINO-ROBOTIS-Systems-Ngoc-ebook/dp/B0BPXGQ6YX
I only use XL320. I will power the openRB with a stabilized 7.5V power supply on the VIN terminal.
I just ordered your book
Thank you for the answer.
Thank you for your support 
I almost forgot: you also need to buy this kind of compatible cables
To connect between the 150 and the XL-320s.
I already have the cables because I use the Dynamixel shiel mkr for another project.
I have sent you my invoice for the sample files of your book.
Sincerely