Information processing apparatus, power source control method thereof, program thereof, and storage thereof

An information processing apparatus includes an information storage to store information indicating a state of the information processing apparatus; an information writing processor to write the information to the information storage; a main power source and an auxiliary power source to supply power to the information writing processor; and a discharge controller to control a discharge speed of the auxiliary power source. When a voltage output of the main power source becomes a reference voltage, the discharge controller switches a power source for the information writing processor from the main power source to the auxiliary power source, and then after completing information writing to the information storage by using the information writing processor and the auxiliary power source, the discharge controller controls the discharge speed of the auxiliary power source to decrease a voltage output of the auxiliary power source to a given voltage within a given time period.