A virtual fieldbus device module is a software or firmware module that enables an otherwise ordinary fieldbus device to become a complex fieldbus device, capable of registering and maintaining multiple fieldbus network addresses for one or more “virtual” fieldbus devices. Each virtual fieldbus device has one or more sensor inputs and appears to the fieldbus network as an individual physical fieldbus device, despite the complex fieldbus device only having one physical connection to the fieldbus network. The virtual fieldbus device module may be incorporated into a device's firmware or may be included in a memory plug-in capable of being removed. The communication packet processing of a complex fieldbus device running the virtual fieldbus device module includes receiving a communication packet over the fieldbus network, determining whether the address associated with the packet matches any of the addresses registered by the complex fieldbus device, and processing any packets that match.