Figure 1. HMD65 Transmitter Board: Service Port, DIP switches, Trimmers, and Screw Terminals 1 RS-485 termination (120 Ω resistor) ON/OFF switch. 2 RS-485 (Modbus/BACnet) screw terminals. 3 Power supply input (15 … 35 VDC or 16 … 24 VAC) screw terminals. 4 Service port for MI70 hand-held indicator and Insight PC software cable connection. 5 DIP switches for setting the HMD65 Modbus RTU or BACnet MS/TP MAC address. 6 DIP switches for selecting Modbus/BACnet communication bit rate and parity (Modbus only). 7 DIP switches for humidity output parameter selection. 8 DIP switch for selecting either Modbus or BACnet mode. 9 Trimmer for humidity measurement adjustment. 10 Screw terminals for humidity measurement output. 11 Screw terminals for temperature measurement output. 12 Trimmer for temperature measurement adjustment. 13 Indicator LEDs: flash when there is RS-485 transmit (TX) or receive (RX) activity.