3 ms·

I use it to wake my NAS a few minutes before a backup job. I've also built a reset-on-LAN card using an old wake-on-LAN-capable NIC and some simple circuitry t

I use it to wake my NAS a few minutes before a backup job. I've also built a reset-on-LAN card using an old wake-on-LAN-capable NIC and some simple circuitry to shape the pulse so it's suitable for the motherboard's reset signal. I send a WOL packet to the otherwise-unused address, and kapow, the presumably-wedged machine is no longer wedged! Writeup here: https://www.i3detroit.org/reset-on-lan-an-ethernet-aware-remote-reboot-device-from-junkbox-parts/ https://www.i3detroit.org/reset-on-lan-an-ethernet-aware-rem...

actionfromafar 4y ago
Very clever! I suppose the modern take would be one of the MCUs with Wifi (ESP8266-like) wire that to the power signal on a PC.
- MayeulC 4y ago
  interesting, one could probably power it from the motherboard itself pretty easily, too! One of the pins of the power switch is probably 5V (though possibly high impedance if a pull-up is used, so not much power). But I think I'll rather look into one of these Pi-based "ilo" with HDMI in and USB gadget support to get remote access to the BIOS as well. It may also be useful for remotely debugging computers of family members :)
  - myself248 4y ago
    Yes, it is powered from the motherboard. The mobo's WOL header, if present, contains +5VSB, wake, and ground. It's intended to power the NIC since the motherboard's slots aren't powered when the machine is off. (At least, ISA slots weren't, and PCI added standby power in a later revision.) Or, you can just tap the +5VSB line from the ATX wiring directly. It's the same as on the WOL header. USB-equipped boards tend to power the USB ports from standby too, to support USB wake events, whether from keyboards, modems, or whatever. Plenty of options. If I were doing it again, yeah, I might use an ESP chip. That would give me power, reset, and serial, and I can always enable a serial console in my OS. I wonder if the ESP32's camera peripheral could read HDMI...

actionfromafar 4y ago

Very clever! I suppose the modern take would be one of the MCUs with Wifi (ESP8266-like) wire that to the power signal on a PC.

MayeulC 4y ago
interesting, one could probably power it from the motherboard itself pretty easily, too! One of the pins of the power switch is probably 5V (though possibly high impedance if a pull-up is used, so not much power). But I think I'll rather look into one of these Pi-based "ilo" with HDMI in and USB gadget support to get remote access to the BIOS as well. It may also be useful for remotely debugging computers of family members :)
- myself248 4y ago
  Yes, it is powered from the motherboard. The mobo's WOL header, if present, contains +5VSB, wake, and ground. It's intended to power the NIC since the motherboard's slots aren't powered when the machine is off. (At least, ISA slots weren't, and PCI added standby power in a later revision.) Or, you can just tap the +5VSB line from the ATX wiring directly. It's the same as on the WOL header. USB-equipped boards tend to power the USB ports from standby too, to support USB wake events, whether from keyboards, modems, or whatever. Plenty of options. If I were doing it again, yeah, I might use an ESP chip. That would give me power, reset, and serial, and I can always enable a serial console in my OS. I wonder if the ESP32's camera peripheral could read HDMI...