automatic power on possible?

Dave Ashley linuxbios at xdr.com
Sat Nov 29 13:02:01 CET 2003


>Does anyone know what the BIOS is doing what linuxbios does not?

The southbridges of the via epia + epia-m have a feature that a specific
bit in the cmos ram will cause the motherboard to be always on. Even when off
it uses the ATX standby power to power a little portion of the southbridge
chip. For our purposes this was insufficient, we need the motherboard to be
*ON!!!* even in the event of cmos content corruption, failure of cmos battery.
So we had to devise a hardware based solution.

I think your thing is something else. The power on at a certain time works
by the machine not really being off, it is in a soft off state. So the range
of power off to full on would be
1)OFF, power supply is completely unplugged
2)Off, nothing functioning but the little bit of standby circuitry
3)Soft off, perhaps cpu is halted, as many things are shut down as possible
4)Fully on

Linuxbios has no presence except at state 2--anything else is beyond its scope.
Conceivably linuxbios could hit the bit to keep the power on all the time.

Note I am just giving my opinion, which is not official in any way.

-Dave




More information about the coreboot mailing list