[ntp:questions] ESR looking for good GPS clocks

Chris Adams cmadams at hiwaay.net
Tue Mar 6 20:20:50 UTC 2012

Once upon a time, Rob  <nomail at example.com> said:
>Of course not.  NTP is software, not hardware.

What would be interesting would be to combine a timing-targeted GPS
module and something like an ARM SoC running Linux and NTP, and then
make the whole thing act as a USB device (bonus points if it can be bus
powered).  Create a custom USB protocol between the device and ntpd on
the host to synchronize the clock (something along the lines of the
network protocol but minus the IP stack).

I expect this would be more accurate than a typical low-cost network
clock, and more accurate than trying to do NMEA+PPS over USB-emulated
RS232.  For a server or device with this as the only USB device, the
jitter should be fairly consistent, and the latency lower than ethernet.
Chris Adams <cmadams at hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.

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