Each state has a different balance relative to power consumption and recovery time, and choosing the right power management strategy as needed can effectively improve computer energy efficiency and user experience.
What are the actions or entry points through which these states are triggered?
S1, notebook low battery automatically or manually set the energy-saving mode will enter the S1, in addition, some manufacturers provide BIOS settings can also be set manually
S2, less frequently used. Either use S1 or S3, if you are considering balancing power consumption and wakeup use S1. Of course, do not rule out special customization needs may consider S2
S3, this is the sleep operation of computer Windows
S4, relatively rare. The laptop will automatically enter this state when the battery level is extremely low, and then plug it in to keep the original user operation state and data will not be lost.
S5, which is the shutdown operation, also has a custom BIOS for power button long press to force shutdown.
Switching on and off is also a common operation, in addition to these there are also timed switching on and off and wake on network.
1. Timed shutdown, which can be achieved by Windows scheduled tasks or application software
2. Timed power-on, also called timed wake-up, is realized according to the power management function provided by the BIOS manufacturer, and the register locations provided by different BIOSes may be different.
Generally divided into cycle timed power on, one-time timed power on, manual operation can enter the BIOS after the power management settings. To know more, you can read this article:Computer timer boot method - chuncn - Blogland ()
For code operation, you can access the read/write methods provided by the BIOS through WinIO, which may vary from BIOS vendor to BIOS vendor. If it is based on Intel's IO, you can roughly refer to the documentation given by IntelIntel(R) Serial IO - Bring Up Guide and release note Rev1. But ask the BIOS vendor for specifics.
3. Wake on Network, that is, through the IP, MAC address to wake up the device
