Meinberg Funkuhren USB5131 and DCF600USB timedelta sensors
umbg driver provides support for Meinberg Funkuhren
USB5131 and DCF600USB time signal receivers for the German DCF77 station.
umbg implements a timedelta sensor and the delta (in
nanoseconds) between the received time information and the local time can be
accessed through the sysctl(8) interface.
The quality of the timedelta is reported as the sensor status:
- No valid time information has been received yet.
- The time information is valid and the timedelta is safe to use for
applications like ntpd(8).
- The time information is still valid, but no new time information has been
decoded for at least twelve hours due to a reception or parity error. The
timedelta should be used with care.
- No valid time information has been received for more than twelve hours
since the sensor state degraded from OK to WARN. This is an indication
that hardware should be checked to see if it is still functional.
A second sensor provides the relative signal quality as a
percentage. The status of this sensor is used to report the status of the
- The clock is synchronized.
- The device's clock is free running on the local oscillator. This is not an
error and can happen due to the nature of the signal transmission using
- Hardware failure, e.g. communication with the device failed.
umbg driver first appeared in