Abstract: An embodiment device includes an input module including a motor configured to generate a rotational force, an output module configured to receive power from the input module to be rotatable, and a connection module having a first side coupled to the input module and a second side, opposite the first side, coupled to the output module, wherein the connection module is configured to transmit the power from the input module to the output module.

Abstract: A method for reporting a power fail in a communication system having a real-time clock (RTC) generator with a backup battery and for performing a reservation function stored in a nonvolatile memory. The method includes the steps of: (a) updating real-time data by storing real-time data from the RTC generator into the nonvolatile memory with a predetermined time interval; (b) initializing the communication system and searching a reservation registering area for a reserved job simultaneously; (c) printing the latest updated real-time data and a power fail title with a power fail time when a reserved job is searched in the step (b); (d) printing a title of the reserved job and reading contents of an unperformed reserved job stored into the nonvolatile memory so as to print the unperformed reserved job; and (e) searching for other reserved job at the completion of the step (d) and, if the other reserved job exists, jumping to the step (d).