Image forming system and method for recovering image forming apparatus from three different power saving modes

摘要

An image forming apparatus has the following three power saving modes: (1) a first power saving mode for cutting off power supply to the load; (2) a second power saving mode for cutting off power supply to the load and setting at least the CPU of the controller to STR state; and (3) a third power saving mode for providing power supply only to a wireless LAN module and the power supply cutoff controller, wherein to recover the image forming apparatus from the power saving mode, an external terminal implements both a second method of transmitting a certain type of packet to the wired LAN module and a third method of transmitting a certain type of packet to the wireless LAN module when the external terminal accesses the image forming apparatus at the application level.

主权项

1. An image forming system comprising: an image forming apparatus and an external terminal being connected to each other via a network, the external terminal being capable of operating the image forming apparatus,
the image forming apparatus comprising: a controller comprising:
a CPU containing an embedded wired LAN module, the CPU having a STR state for reducing power consumption by cutting off core power supply and a recovery function for terminating the STR state by restoring the core power supply when the wired LAN module receives a certain type of packet, anda wireless LAN module having a control function for outputting a control signal when the wireless LAN module receives a second certain type of packet while the image forming apparatus is saving power; and a power supply cutoff controller that controls cutting off or providing power supply to a load, wherein when the wireless LAN module outputs the control signal to the power supply cutoff controller, the power supply cutoff controller provides power supply to the load if the control signal is effective, the image forming apparatus having the following three power saving modes: (1) a first power saving mode for cutting off power supply to the load; (2) a second power saving mode for cutting off power supply to the load and setting at least the CPU of the controller to the STR state; and (3) a third power saving mode for providing power supply only to the wireless LAN module and the power supply cutoff controller, the external terminal being capable of recovering the image forming apparatus from the first, second, and third power saving mode by the following respective methods: (1) a first method of the external terminal accessing the image forming apparatus at the application level; (2) a second method of the external terminal transmitting the certain type of packet to the wired LAN module; and (3) a third method of the external terminal transmitting the second certain type of packet to the wireless LAN module, wherein the external terminal implements both the second method and the third method before the external terminal implements the first method to access the image forming apparatus at the application level.