PPS on serial port


I’ve been running a GPS with NMEA and PPS outputs connected to a server with a DB25 serial port. The PPS is wired to the DCD pin with the type 20 generic NMEA driver. The new server that I would like to connect the GPS to has a Cisco/Sun type RJ-45 serial port that lacks the modem control pins. I can’t find any documentation that mentions using DSR for the PPS. Is there a reference clock driver that will recognize the PPS on a flow control pin?


What OS?

If you are using linux you can use GPSD which I believe supports PPS on alternate pins. Then you use a SHM refclock with NTP to talk to GPSD.


Nothing to do with gpsd, as PPS handling it done at the kernel level.

I personally just ended up buying a cheap PCIe serial (or parallel!) card from Amazon and using that.


This is a Sun/Oracle server running Solaris.


I did a little digging around and @jailbird is right, this is implemented in the kernel (timepps.h which is used by NTP merely interfaces with it).

I would have to agree, easiest route without making a ton of headaches for yourself would be to simply drop in a serial port card that has a chip solaris supports and connect to the DCD pin.


Thanks for the info. I’ll take a look at adding serial hardware.