Image forming apparatus for communicating with sheet processing apparatus for executing post-process to sheet

A control method for an image forming system having an image forming apparatus which forms an image onto a sheet and a sheet processing apparatus which is connected to said image forming apparatus and executes a post-process to said sheet, comprising:

• a detecting step of detecting an abnormality in communication between said image forming apparatus and said sheet processing apparatus;
• an avoiding step of executing an avoiding process for the abnormality when the communication abnormality is detected in said detecting step;
• a preprocessing step of executing a preprocess for a power shutdown in accordance with an operation of a power switch to shut down a power source of said image forming system;
• and
• a control step of not executing said detecting step during said preprocessing step.

An image forming system having an image forming apparatus which forms an image onto a sheet and a sheet processing apparatus which is connected to said image forming apparatus and executes a post-process to said sheet, comprising:

• a communicating device which communicates with said image forming apparatus and said sheet processing apparatus;
• an abnormality detecting device which detects an abnormality in communication in said communicating device;
• a controller which executes an abnormality countermeasure process for controlling continuation or halt of execution of image creation when the communication abnormality is detected by said abnormality detecting device;
• a power switch which is operated to shut down a power source of said image forming system;
• and
• a power control device which, when said power switch is operated, shuts down the power source after a preprocess for the power shutdown was executed,
• wherein even if said communication abnormality is detected during the execution of said preprocess, said controller ignores said communication abnormality and does not execute said abnormality countermeasure process.

An image forming system having an image forming apparatus which forms an image onto a sheet and a sheet processing apparatus which is connected to said image forming apparatus and executes a post-process to said sheet, comprising:

• a communicating device which communicates with said image forming apparatus and said sheet processing apparatus;
• an abnormality detecting device which detects an abnormality in communication in said communicating device;
• a controller which executes an abnormality countermeasure process for controlling continuation or halt of execution of image creation when the communication abnormality is detected by said abnormality detecting device;
• a power switch which is operated to shut down a power source of said image forming system;
• and
• a power control device which, when said power switch is operated, shuts down the power source after a preprocess for the power shutdown was executed,
• wherein said abnormality detecting device does not detect the communication abnormality during the execution of said preprocess.