2.2.3Power OFF Process

Overview

Turns off the system power. However, the power to all the devices is not turned off and some can be used for storing the information required for the next resume operation. This process is called the suspend process and the state of the system while off is called the suspend state.

The suspend process can be divided into two categories: one is the normal suspend process which is the usual off method and the other is the critical suspend process to execute the emergency escape process for protecting the system from drops or bumps. Either of these suspend processes will be selected depending on the OFF factor, as described later.

Normal Suspend Process

If the Power switch is held down for more than one second while system is on, the system power will be turned off. The process that takes place at this time is the normal suspend process. Before this suspend process is executed, the application currently running is informed of the suspend request (OFF factor) by the system. Then the system stores the information required for resumption and turns off the power.

Hereinafter the suspend process (or OFF process) refers to the normal suspend process.

For information about the method used by each application to detect the occurrence of an OFF factor (suspend event), refer to Chapter 9.5 “Remaining Battery Voltage Display Utility”.

Critical Suspend

This is a suspend process that takes place in an emergency. Since this critical suspend process should achieve its escape process with very little power in the system, only essential information can be retained.

The system will not inform the application currently running of the fact that it is critically suspended. However, the application will be informed of the fact that it was critically suspended at resumption.

For information about the method used by each application to receive this information, refer to Chapter 9.5 “Remaining Battery Voltage Display Utility”.

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Casio IT-2000W manual Power OFF Process, Normal Suspend Process, Critical Suspend