Extensible Firmware Interface Specification
3.6.4
SetWakeupTime()
Summary
Sets the system wakeup alarm clock time.
Prototype
EFI_STATUS
SetWakeupTime (
IN BOOLEAN
IN EFI_TIME
);
Parameters
Enable
Time
Description
Setting a system wakeup alarm causes the system to wake up or power on at the set time. When the
alarm fires, the alarm signal is latched until acknowledged by calling
disable the alarm. If the alarm fires before the system is put into a sleeping or off state, since the
alarm signal is latched the system will immediately wake up. If the alarm fires while the system is
off and there is insufficient power to power on the system, the system is powered on when power is
restored.
For an ACPI-aware operating system, this function only handles programming the wakeup alarm
for the desired wakeup time. The operating system still controls the wakeup event as it normally
would through the ACPI Power Management register set.
The resolution for the wakeup alarm is defined to be 1 second.
During runtime, if a PC-AT CMOS device is present in the platform the caller must synchronize
access to the device before calling SetWakeupTime().
Status Codes Returned
EFI_SUCCESS
EFI_INVALID_PARAMETER
EFI_DEVICE_ERROR
90
Enable,
*Time
OPTIONAL
Enable or disable the wakeup alarm.
If
, the time to set the wakeup alarm for. Type
Enable
is
TRUE
is defined in Section 3.6.1. If
EFI_TIME
parameter is optional, and may be NULL.
Enable
TRUE
If
is
, then the wakeup alarm was enabled. If
Enable
FALSE
is
, then the wakeup alarm was disabled.
A time field is out of range.
The wakeup time could not be set due to a hardware error.
12/12/00
is FALSE, then this
Enable
to
SetWakeupTime()
Version 1.02
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