Copyright (c) 2008 Marc Balmer <mbalmer@openbsd.org>
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.Dd $Mdocdate: May 6 2008 $ .Dt MSTS 4 .Os .Sh NAME .Nm msts .Nd Meinberg Standard Time String timedelta sensor .Sh SYNOPSIS .Cd "pseudo-device msts" Op Ar count .Sh DESCRIPTION This line discipline interfaces serial Meinberg devices.
p The line discipline is enabled by the following sequence: d -literal -offset indent #include <sys/ttycom.h> int ldisc = MSTSDISC, fildes; ... ioctl(fildes, TIOCSETD, &ldisc); .Ed
p The byte stream is unaltered by the line discipline which maintains a timedelta sensor using the MSTS data. The timedelta sensor will appear as msts* in the list of sensors and the delta (in nanoseconds) between the received time information and the local time can be accessed through the .Xr sysctl 8 interface.
p The Meinberg radio clocks use the following default baudrates:
p l -tag -width "GPS-receivers (external and PCI, COM0)XXX" -offset indent -compact t GPS-receivers (external and PCI, COM0) 19200/8N1 t GPS-receivers (external, COM1) 9600/8N1 t DCF77-receivers (external) 9600/7E2 t DCF77-receivers (PCI) 4800/8N1 .El .Sh SENSOR STATES The quality of the timedelta is reported as the sensor status: l -tag -width "CRITICALXX" -offset indent t OK The time information is valid. The timedelta is safe to use for applications like .Xr ntpd 8 . t WARN The attached receiver has been indicating a warning condition for at least the last ten minutes. The timedelta should be used with care. t CRITICAL tty timestamping has been turned on but there is no PPS signal present or the receiver indicated a warning condition for at least the last twenty minutes. Check your hardware. Some receiver units need PPS to be manually turned on. .El
p The status of a second sensor is used to report the status of the device itself: l -tag -width "CRITICALXX" -offset indent t OK The clock is synchronized, e.g. a GPS receiver has a fix. t WARN The device issued a warning condition, e.g. a GPS receiver has no fix. .El .Sh SEE ALSO .Xr tty 4 , .Xr ldattach 8 , .Xr ntpd 8 , .Xr sysctl 8 .Sh HISTORY The .Nm interface first appeared in .Ox 4.3 . .Sh AUTHORS The .Nm line discipline was written by .An Marc Balmer Aq Mt mbalmer@openbsd.org .