An electronic device includes a subunit (e.g., monitor) for receiving and processing input data. The subunit includes one or more functional blocks, with at least one functional block operative as a termination device such as a display, printer or audio speaker to terminate (e.g., transform and output) the processed input data of the subunit. The electronic device further includes a memory for storing information pertaining to the termination device. Preferably, the electronic device is configured to communicate with other devices in a serial bus connected system employing channels for time division multiplexed communication. The information pertaining to the termination device stored in the memory preferably includes "virtual plug" information for the termination device, indicating, for example, the number of logical connections that the termination device can maintain. The memory is accessible by an external apparatus to thereby enable the external apparatus to readily obtain the logical connection state of the termination device and facilitate operations.