DougieLawson wrote:WOL relies on having a BIOS that is listening for the magic packet on the network interface.
Not sure what you mean by BIOS but most NIC and network controllers can run entirely standalone without interaction with the PC they are within. The network controller is more than capable of detecting a magic packet to itself providing it knows its own MAC address without assistance from any other host. WOL could be pretty pointless if it didn't work that way.
In most PC's everything is powered down except "5V Standby" which is what the network hardware runs off ( and a primary reason why 5V Standby came into existence ). The network controller remains on when the motherboard is otherwise off, runs all by itself, detects the magic packet based on MAC address, and simply has to assert an output signal when it sees that packet. The WOL signal is usually an open collector signal which is paralleled to the power button so it's activation is exactly like pressing the power button - okay, a bit more complicated than that electrically but basically that's it.
One might have to adjust BIOS settings on a PC to have that PC actually wake-up when WOL is asserted but that's configuring the host PC not the NIC WOL functionality.
As said I have done this, just 0V and 5V and you have signal out of the NIC which asserts whenever it gets a magic packet. I don't have any further details to hand but here's a very similar project along the same lines -
https://www.i3detroit.org/reset-on-lan- ... kbox-parts