Two things: You can pipe the GPS right into the serial port on the raspberry pi, making the whole thing smaller. Your GPS is an accurate time source, and assum

Two things: You can pipe the GPS right into the serial port on the raspberry pi, making the whole thing smaller. Your GPS is an accurate time source, and assuming it has a backup battery, or at least the sight of one satellite it can spit out a timestamp that you can feed into NTP: http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html