NTPv3 refclocks

Last update: May 4, 2022 17:05 UTC (dbea9b7d4)

This is a short overview for the reference clocks currently supported by xntp V3. Ultimate wisdom can be obtained from xntpd/refclock_*.c. This page was derived from that information - unfortunately some comments in the files tend to get stale - so use with caution.

Refclock address Type
127.127.0.x no clock (fails to configure)
127.127.1.x local clock - use local clock as reference
127.127.2.x no clock (fails to configure)
127.127.3.x PSTI 1010/1020 WWV Clock
127.127.4.x SPECTRACOM WWVB receiver 8170 and Netclock/2
127.127.5.x Kinimetric Truetime 468-DC GOES receiver
127.127.6.x IRIG audio decode (Sun & modified BSD audio driver)
127.127.7.x CHU Timecode (via normal receiver & Bell 103 modem)
127.127.8.x PARSE (generic driver for a bunch of DCF/GPS clocks; can be extended for other clocks too). x can be:
0-3: Meinberg PZF535/TCXO
4-7: Meinberg PZF535/OCXO
8-11: Meinberg DCF U/A 31
12-15: ELV DCF7000
16-19: Walter Schmid DCF receiver (Kit)
20-23: Conrad DCF77 receiver module + level converter (Kit)
24-27: TimeBrick (limited availability ask time@informatik.uni-erlangen.de)
28-31: Meinberg GPS166
32-35 Trimble SV6 GPS receiver
127.127.9.x MX4200 GPS receiver
127.127.10.x Austron 2201A GPS Timing Receiver
127.127.11.x Kinemetrics Truetime OM-DC OMEGA Receiver
127.127.12.x KSI/Odetecs TPRO-S IRIG-B / TPRO-SAT GPS
127.127.13.x Leitch: CSD 5300 Master Clock System Driver
127.127.14.x MSFEES
127/127.15.x TrueTime GPS/TM-TMD
127.127.16.x Bancomm GPS/IRIG Ticktock
127.127.17.x Datum Programmable Time System