Copyright 2018 by the Digital Aggregates Corporation, Arvada Colorado, USA.
Licensed under the terms of the FSF GPL v2.
Cesium is not much more than a simple script that uses NTP and its ntpq command to monitor in real-time the various NTP servers/clocks on my local network. (I have a few, both home brew and commercial.) It automatically starts up providing the "pi" user is configured to automatically log in at boot time. It runs on a Raspberry Pi with a 7" touch-sensitive LCD display. It just sits on my desk and occasionally I touch the screen to bring it out of power-save mode and check the display to see what my clocks are doing.
My NTP clocks are Hourglass (uses a serial GPS receiver), Astrolabe (uses a chip-scale cesium atomic clock), Obelisk (uses a home-brew WWVB receiver), and Candleclock (uses a USB GPS receiver).
Recently I've installed Lady Heather, an open source GPS monitoring tool (see link below), on this system. Now my .profile script brings up a second window running Lady Heather on a USB GPS device at /dev/ttyUSB0 (I'm using a NaviStar GR-701W).
Even more recently, I've added a third window to run my own Hazer gpstool with a second USB GPS device at /dev/ttyACM0 (this one is a GlobalSAT BU-353W10). Hazer's gpstool is built on top of the Hazer C library and also my Diminuto C library.
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3440 Youngfield Street
Wheat Ridge CO 80033 USA
Enable auto-login (and SSH if you want it, I do) using the Pi's on-screen menus.
cd cd src apt install bison libevent-dev libcap-dev libssl-dev libreadline-dev git clone https://gitlab.com/NTPsec/ntpsec.git cd ntpsec ./waf configure --refclock=shm ./waf build ./waf install cd cd src git clone https://github.com/coverclock/com-diag-diminuto cd com-diag-diminuto/Diminuto make pristine depend all sudo make install cd cd src git clone https://github.com/coverclock/com-diag-hazer cd com-diag-hazer/Hazer make pristine depend all sudo make install
Install all the files in the overlay directory in the appropriate spots.