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Windows Embedded CE 6.0 R3


This function resets a system timer that controls whether or not the device will automatically go into a suspended state.


void WINAPI SystemIdleTimerReset(void); 



Return Value



When a device has run for a specified period of time, by default it goes into a suspended state. The system timer that controls this functionality uses a time interval specified in the registry. This interval is dependant on whether the device is on AC or battery power.

You can override the system timer by calling the SystemIdleTimerReset function more frequently than the values in the registry. Use the smaller of the two registry values.

The following registry key returns the time interval if the device is on AC power:


The following registry key returns the time interval if the device is on battery power:


If the Power Manager is managing timeouts, calls to SystemIdleTimerReset will still reset the GWES timeout and cause the screen saver to stop showing.


This function must be use appropriately. On battery-powered devices, a program that never suspends (or sleeps) by continually calling SystemIdleTimerReset can quickly drain the batteries.


Header winuser.h
Windows Embedded CE Windows CE 2.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also

Other Resources

Preventing Automatic Power Down