diff options
Diffstat (limited to 'share')
| -rw-r--r-- | share/man/man4/udcf.4 | 48 |
1 files changed, 43 insertions, 5 deletions
diff --git a/share/man/man4/udcf.4 b/share/man/man4/udcf.4 index 0cd4652419a..3af5e32b4bd 100644 --- a/share/man/man4/udcf.4 +++ b/share/man/man4/udcf.4 @@ -1,4 +1,4 @@ -.\" $OpenBSD: udcf.4,v 1.5 2006/04/21 16:46:34 mbalmer Exp $ +.\" $OpenBSD: udcf.4,v 1.6 2006/04/27 08:23:30 mbalmer Exp $ .\" .\" Copyright (c) 2006 Marc Balmer <mbalmer@openbsd.org> .\" @@ -19,19 +19,51 @@ .Os .Sh NAME .Nm udcf -.Nd Gude ADS Expert mouseCLOCK DCF77 time signal receiver +.Nd Gude ADS Expert mouseCLOCK DCF77/HBG time signal station receiver .Sh SYNOPSIS .Cd "udcf* at uhub?" .Sh DESCRIPTION The .Nm driver provides support for the Gude ADS Expert mouseCLOCK, a receiver for the -German DCF77 time signal station. +German DCF77 and the Swiss HBG time signal stations. .Nm -implements a time delta sensor and the delta (in msec) between the received -time information and the local time can be accessed through the +implements a time delta sensor and the delta (in nanoseconds) between the +received time information and the local time can be accessed through the .Xr sysctl 8 interface. +.Sh CLOCK TYPE +The driver automatically detects if it is receiving the German DCF77 timecode +or the Swiss HBG timecode and indicates the clock type in the sensor +description. This value will not be changed once set, even when the receiver +module is changed at runtime. +.Bl -tag -width "DCFXX" +.It DCF77 +German DCF77 time signal station +(77.5 kHz longwave transmitter located in Mainflingen near Frankfurt) +.It HBG +Swiss HBG time signal station +(75 kHz longwave transmitter located in Prangins near Geneva) +.El +.Sh SENSOR STATES +The quality of the time delta is reported as the sensor status: +.Bl -tag -width "CRITICALXX" +.It OK +The time information is valid and the receiver is fully synchronized to the +time signal station. +The time delta is safe to use for applications like +.Xr ntpd 8 . +.It WARN +The time information is valid, but there has been a reception or parity error. +The sensor value is adjusted using the local clock for at most 15 minutes. +The time delta should be used with care. +.It CRITICAL +No valid time information has been received for more than 15 minutes. +This is an indication that hardware should be checked +to see if it is still functional. +The time delta will eventually degrade to a lie +as all computer internal clocks have a drift. +.El .Sh SEE ALSO .Xr intro 4 , .Xr uhub 4 , @@ -42,3 +74,9 @@ The .Nm driver first appeared in .Ox 4.0 . +.Sh AUTHORS +.An -nosplit +The +.Nm +driver was written by +.An Marc Balmer Aq mbalmer@openbsd.org . |