How to trigger S1 in sleeper

[Jiajun]

Hi,
I'm now using the sleeper tool from your Website. It's very useful. But I am curious that how the tool triggers S1 operation. I searched Windows SDK and find some functions to make system into S3/S4 state, no S1. So how can the tool implement that?
If you can tell me some hints, I will very apprecriate that.
Thanks a lot.

[David (PassMark)]

See this previous post.