Patent ID: 8760672
Filing Date: 2014-06-24
Classification: G06F,H04N

Abstract:
1. An image forming apparatus operating in at least two modes including a normal mode and a power-saving mode comprising: a first CPU configured for controlling operations performed by the image forming apparatus in the normal mode and configured to suspend its operation in the power-saving mode, the first CPU including an oscillator for generating and outputting a first clock signal; a second CPU connected to the first CPU and configured for controlling operations performed by the image forming apparatus in the power-saving mode and for controlling the amount of time the image forming apparatus operates in the power-saving mode, the second CPU including a timer for generating and outputting a second clock signal having a timer error larger than the timer error of the first clock signal, and the second CPU configured for measuring a time period based on the second clock signal; and a detection unit configured to detect a remaining amount of paper; wherein the second CPU has a receiving unit that receives the first clock signal and a correction unit that corrects the time period measured based on the second clock signal by using the first clock signal received by the receiving unit, and controls the detection unit so as to detect a remaining amount of paper in response to the second CPU measuring a predetermined time period in the power-saving mode.