Entering Standby Mode; Wakeup; Power Button Functionality - VersaLogic Tiger Reference Manual

E S
NTERING TANDBY
Standby mode can be entered through the OS (by configuring the standby settings in Power
Options Properties) or programmatically, through a function call or the execution of a shutdown
utility.
SetSystemPowerState Function
The "Power Management Reference" in the
the API available for power control under Windows. The "Power Management Functions"
section provides complete information on the use of the API.
The function used to set the system power state is SetSystemPowerState. This function suspends
the system by shutting power down. Depending on the ForceFlag parameter, the function either
suspends operation immediately or requests permission from all applications and device drivers
before doing so.
BOOL SetSystemPowerState(
BOOL fSuspend,
BOOL fForce
);
Parameters:
fSuspend
[in] If this parameter is TRUE, the system is suspended. If the parameter is FALSE, the
system hibernates. This parameter is ignored in Windows Me/98/95.
fForce
[in] If this parameter is TRUE, the function broadcasts a PBT_APMSUSPEND event to
each application and driver, then immediately suspends operation. If the parameter is
FALSE, the function broadcasts a PBT_APMQUERYSUSPEND event to each
application to request permission to suspend operation.
W
AKEUP
The system will wake with one power button push. It can also wake (with software support) from
the Ethernet, serial port, or USB.
P B
OWER UTTON
The power button input of the VL-EPM-24 is a simplified version of that described in ACPI
Specification 2.0. There is no software interface to observe or configure its behavior. The power
button has direct control of the system power state. When the system is in the S0 state (fully on),
pressing the power button will shut off the VL-EPM-24 and place it into the S5 state (off). No
event signal is given to the OS and the system will not wait for the OS to shutdown before
removing power to the CPU and chipset.
VL-EPM-24 Reference Manual
M
ODE
F
UNCTIONALITY
MSDN Library contains complete information on
System Features
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