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2.8.2
Power key control
The Power key must be pressed for approximately one second for the system to recognize turning
on the power.
The Power key must be pressed for approximately one second for the system to recognize turning
off the power.
(1) Disabling the Power key after turning on the power
After turning on the power, the Power key will be disabled for a certain period of time. This prevents
the power being turned off during the transition stage while drivers are being restored. This disabled
time period can be set with the system library.
For details, refer to the System Library Manual.
(2) Disabling the Power key
After the FlashDisk or Micro SD card is accessed, the Power key will be disabled for a certain period
of time. This prevents the power being turned off while disk access continues.
This disabled time period can be set with the system library.
The Power key is also disabled for the period specified in the critical path while a communications
function is in use.
For details, refer to the System Library Manual.
(3) Disable turning off the power
It is possible to disable turning off the Power key from the system library. This is based on the
following envisaged situations:
- The application meeds to perform a shutdown process before the system turns the power off
- The user does not want to turn the power off during a required process.
If the Power key is pressed down while the Power key is disabled, the system broadcasts a
message to application software without turning off the power.
WM_POWERBROADCAST
PBT_APMSUSPEND
The message is issued only once when the Power key is pressed for the first time after setting.
The setting is canceled by turning the power off, or by a reset.
For details, refer to the System Library Manual.
This function is used to realize the virtual off state. Refer to the section on virtual off.
