The operator interface device for an HMI system provides for generic, simple communication between Human-Machine Interface (HMI) software and an operator workstation. The device has at least one signaling device, at least one serial communication port, and an Ethernet port mounted on a housing. Disposed within the housing is electronic circuitry that includes a microcontroller having embedded Ethernet capability. The microcontroller is configured to pass serial data from a bar code reader, RFID receiver, or the like from the serial communication port via Ethernet by TCP/IP to the HMI software on a remote server, and to control driver(s) for the at least one signaling device, which may be a beacon, a light, a horn or other audio device, or a push button switch. The device may also include a power supply and miniconnector port for passing signals between a machine controller, such as a torque controller, and the HMI software.