CEDEVICE_POWER_STATE (Compact 2013)
3/26/2014
This enumeration describes the device power states. The PwrDeviceUnspecified and PwrDeviceMaximum values are not valid device power states but are used for some Power Manager functions.
Syntax
typedef enum _CEDEVICE_POWER_STATE {
PwrDeviceUnspecified = -1,
D0 = 0,
D1,
D2,
D3,
D4,
PwrDeviceMaximum
} CEDEVICE_POWER_STATE, *PCEDEVICE_POWER_STATE;
Elements
- PwrDeviceUnspecified
System state is unspecified.
- D0
Full On. This is the state in which the device is on and running. It is receiving full power from the system and is delivering full functionality to the user.
- D1
Low On. This is the state in which the device is fully functional at a lower power state than D0, a lower performance state than D0, or both. This state is applicable when the device is being used, but where peak performance is unnecessary and power is at a premium.
- D2
Standby. This is the state in which the device is partially powered with automatic wakeup on request. The device is effectively standing by.
- D3
Sleep. This is the state in which the device is partially powered with device-initiated wakeup if available. A device in state D3 is sleeping but capable of raising the system power state on its own. It consumes only enough power to be able to do so; which must be less than or equal to the amount of power used in state D2.
- D4
Off. This is the state in which the device is not powered. A device in state D4 should not be consuming any significant power. Some peripheral busses require static terminations that intrinsically use non-zero power when a device is physically connected to the bus; a device on such a bus can still support D4.
- PwrDeviceMaximum
Valid device power state values are greater than PwrDeviceUnspecified and less than PwrDeviceMaximum.
Requirements
Header |
pm.h |