6:48 PM - GPS on Ubuntu
Purchased a USB gps device to play around with on Ubuntu 22.04. Device is https://smile.amazon.com/dp/B00NWEEWW8?ref=ppx_yo2ov_dt_b_product_details&th=1
The device is recognized as /dev/ttyACM0. You can cat it to see it's working.
Setup for ntpd
sudo apt-get update
sudo apt-get install gpsd gpsd-clients ntp
sudo vi /etc/defaults/gpsd
DEVICES="/dev/ttyACM0"
GPSD_OPTIONS="-n"
n flag is required for NTP to work.
sudo vi /etc/ntp.conf
gps
server 127.127.28.0 minpoll 4 maxpoll 4 prefer
fudge 127.127.28.0 time1 0.000 refid GPS stratum 15
Test lock with:
cgps -s
ntpq -p
...and you'll see a line in the resulting text that looks something like this:
*SHM(0) .GPS. 15 l 14 16 377 0.000 3.505 3.556
If "poll" and "reach" are zero it's not working.