If the M665 motors are connected via an USB adaptor, we define:
define /device=piezo_motor/module=m665/ifc="/dev/ttyUSB7"/chan=1 mot51 define /device=piezo_motor/module=m665/ifc="/dev/ttyUSB7"/chan=2 mot52 define /device=piezo_motor/module=m665/ifc="/dev/ttyUSB7"/chan=3 mot53