HDL Bus Enable Hotel I/O Module supports functions of MOSFET dimming, relay, curtain control, dry contact, doorbell control and LED output. The three service status indicators of the indoor doorbell can be controlled by the universal switch of the panel. The output channel parameters are set by HDL Buspro Setup Tool, and curtains, lamps, exhaust fans, etc. can be set as controlled targets. After setting, the targets can be controlled via the panel.