Power Management

[Michells]

Hello All,

I am investigating on how Windows shutdowns the PC.


I mean: When the shutdown(HardKey) is pressed once,all my applicaiton
closes and system shutdowns.


My Question:


1) When I press Shutdown(Hardkey) once. which API is being used by
the
OS
2) If yes (i.e OS uses some Power management API) How will this API
is
being called and who calls it, when I press Shutdown button.
(Hardkey).


Note:Hardkey refers the button that every PC have on the CPU (i.e
Shutdown and Reset buttons)


Regards
Michells

 

[Wesley Vogel]

WTF is a HardKey? Do you mean the Power button on the computer case?

Depends on how When I press the power button on my computer: is set in Power
Options Properties.

Start | Run | Type: powercfg.cpl | Click OK |
Advanced tab | Under Power buttons |
When I press the power button on my computer:
Do nothing
Ask me what to do
Stand by
Shut down

Power buttons
[[Specifies whether your computer takes an action (for example, goes into a
low-power state) when you press the Power button.]]

Normally you do not use the power button to turn off the machine.

To turn off the computer
Click Start, click Shut Down, and then, in the drop-down list, click Shut
down.

This action shuts down Windows so that you can safely turn off the computer
power. Many computers turn the power off automatically.

Even my 9 year old machine powers down automatically when clicking Shut
down.

Actually, I use a shortcut to %windir%\System32\shutdown.exe -s -t 00 on
both of my machines instead of Start | Turn Off Computer | Shut down.

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In

 

[Michells]

Thanks Wesley.

Whatever u have suggested is done from the OS side. I just wanted to
know from H/W side. I mean when I press POWER key to shutdown or START
the system, how exactly the flow happens until the system shutsdown
completely or gets Booted completely.

For Example:

Imagine that the system is in OFF state. When I press POWER key to
start my system,how will be the power flow to the Processor. When I
read the specification of my motherboard, POWERBTN was connected to D5
and from there I was not able to understand the further process.

So I need the complete power architecture of the PC.

Regards
Michells

 

[Wesley Vogel]

Michells, if you're serious about this, you can start with these.

How Microprocessors Work
http://computer.howstuffworks.com/microprocessor.htm

How PCs Work
http://www.howstuffworks.com/pc.htm

Howstuffworks "Computer Channel"
http://computer.howstuffworks.com/

--
Hope this helps. Let us know.

Wes
MS-MVP Windows Shell/User

In