Assume I connect a microcontroller board (like an Arduino) to a Windows 7 PC via USB. Is there anything in the USB communication protocol that contains host clock data? In other words, can I sync the microcontroller to the PC clock just by hooking up to USB?
If that's not possible, could you suggest some clever minimal-effort way to get the clock info from PC to Arduino?
I guess I could always write some software to run on the PC in the background and provide that information to the Arduino, and I'll do that if I must, but I'd like to avoid that.
I could also use a network shield and have the Arduino query the PC over the network, but I'd like to keep cost and complexity down by not using any extra shields.
I could also have the Arduino run its own clock base, but that's not an option - it must be synchronised to this particular PC down to the second, even if the PC itself is out of synchronisation with NTP.