Patent ID: 8032774

Claim:
An information processing apparatus comprising: a main system controlling an operation of the information processing apparatus; and a subsystem connected to and communicating with the main system via a communication control line to perform information processing functions, wherein the subsystem includes a first subsystem that controls information display on a display unit, wherein the main system includes a mode changeover unit that, according to a predetermined condition, changes a mode of the information processing apparatus to one of a regular operation mode in which given power is supplied to the main system and the subsystem, and an energy-saving mode in which power lower than power supplied in the regular operation mode is supplied to the main system and the subsystem; a first signal output unit that when the mode changeover unit changes the mode of the information processing apparatus from the energy-saving mode to the regular operation mode, outputs a power control signal indicating the mode changeover of the information processing apparatus; and a second signal output unit that when the mode changeover unit changes the mode of the information processing apparatus from the energy-saving mode to the regular operation mode, determines necessariness of information display on the display unit and outputs a starting mode selection signal indicating a result of the determination, wherein the first subsystem includes an apparatus information obtaining unit that when the mode changeover unit changes the mode of the information processing apparatus from the regular operation mode to the energy-saving mode, obtains apparatus information on the information processing apparatus from the main system; a first signal detecting unit that detects the power control signal output from the first signal output unit; a second signal detecting unit that detects the starting mode selection signal output from the second signal output unit; and a display control unit that controls display of information on the display unit, the information containing the apparatus information obtained by the apparatus information obtaining unit, based on the power control signal detected by the first signal detecting unit and the starting mode selection signal detected by the second signal detecting unit.