W83977F Datasheet, PDF (112/181 Pages) Winbond – PLUG & PLAY 1.0A COMPLIANT

W83977F/ W83977AF
6.4 "On-Now" Control
PRELIMINARY
The "On-Now" Control function is built in RTC. It enables the PC to be powered on automatically
from triggers of various events, and to be powered off in an orderly controlled fashion.
The "On-Now" works at all times even when the system power is switch-off or disconnected. It
detects several external events to control system power supply On/Off properly (e.g. telephone ring,
panel switch-off). It also controls the signal (PSCTRL ) to turn the power supply on or off.
6.5 Power-On Events
The "On-Now" Control turns on power supply when one of the following events occurs:
• Panel Switch "turned on"
• Telephone is ringing
• Ring-In detection signal comes from a modem
• Keyboard/Mouse is stroked/moved
• Power-wake-up input goes from high to low.
• PSCTRL active when power returns after a power-failure occurs.
(Note: Panel-Switch has a debounce circuit which is clocked by RTC 32.768KHz oscillator. The "On-Now" control will not function
properly if this oscillator fails to work and PC can not be powered-on consequently)
6.6 Power-Off Events
• Panel Switch "turned off"
• Power-off under software control
• Power-failure event
• Override Power off: Panel switch is pushed for at least 4 seconds, then the system will be forced
to turn off immediately
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Publication Release Date: January 1997
Revision 0.50