Hi BobBuilt,
Yes, you are right X-PID is not using USO commands but it is using synaptrix I/O . I am not using any separate code for driving servos, the code is provided (X-PID firmware)by sirnoname and there is no serial.println in this code. I think according your previous post you have also used it. you may know it better than me. can you please guide me to set the synaptrix