From: Neil Cobbett <[email protected]> Reply-To: <[email protected]> Date: Sunday, February 2, 2014 at 8:17 PM To: <[email protected]> Subject: [beagleboard] Systemd configuring /dev/gps0 for ntpd
> Hi, > > I am using BBB with a GPS to get system time into NTP using the NMEA string. > I've done this a few times before. > I have no network connection for ntpd. (It works if I have a network > connection but NOT with /dev/gps0 as the only time server) > > The problem: > I map /dev/ttyO1 to /dev/gps0 as a rule in /etc/udev/rules.d > > systemd boots as usual and when ntpdate.service executes /dev/gps0 still isn't > ready so NTPd fails and hangs since it can't find a time server. > I end up manually having to kill ntpd and restart the ntpdate service again > > I have managed to force it to work by disabling ntpdate.service and > ntpd.service in systemd and instead use CRON to call ntpd 30 seconds after > boot with a 'sleep 30'. A rubbish solution I know! > But it does highlight the fact that NTPd should not run before /dev/gps0 > exists if NTP is to work properly. > > My questions - > > 1. How do I get ntpdate.service to only run when /dev/gps0 already exists? > i.e. wait until /dev/gps0 is streaming NMEA data. > > I have tried a number of 'Before' and 'After' commands in > /lib/system/systemd/ntpdate.service with no apparent change. > > > 2. Why is the creation of /dev/gps0 taking so long? udev seems to be > configuring this rule very slowly. It's only a serial port mapping so why > take 10's of seconds? Is it possible GPS has to acquire satellites before /dev/gps0 is created? > > Any help greatly appreciated! > Neil > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
