Patent ID: 8651601

Claim:
A printing apparatus comprising: a power supply control unit configured to control power supply to respective units included in the printing apparatus, from a power supply unit; a printing unit configured to print at a normal operation mode; and a controller unit, including: an interface unit for connecting to an extension board which includes a communication unit for communicating with an external; a first controller for controlling the printing unit and the power supply control unit; and a first timer, wherein, in a case where the extension board connected via the interface unit has a second controller and second timer and a condition for changing from the normal operation mode to a power saving mode is satisfied, the second controller instructs the second timer to time until the predetermined time period elapses, and instructs the power supply control unit to cause the printing apparatus to change from the normal operation mode to the power-saving mode by stopping supplying power to al least the printing unit, the first controller and the first timer, and in a case where the predetermined time period elapsed since the printing apparatus changed from the normal operation mode to the power-saving mode, the second controller instructs the power supply control unit to resume the power supply, and causes the printing apparatus to return from the power-saving mode to the normal operation mode.