Chapter 2 Specifications and Functions Descriptions 9 10 11 2__ 12 13 14 2-9 Number Description ⑨ USB port for programs to be uploaded or downloaded ⑩ RUN/STOP switches ⑪ DC power ⑫ RS-485 communications ( two sets of RS-485 communicaiton interfaces) ⑬ Reset button ⑭ Slot for a program card