MBG(4) - Device Drivers Manual

MBG(4) - Device Drivers Manual #

MBG(4) - Device Drivers Manual

NAME #

mbg - Meinberg Funkuhren timedelta sensor

SYNOPSIS #

mbg* at pci?

DESCRIPTION #

The mbg driver provides support for Meinberg Funkuhren radio clocks (time signal station and GPS receivers). mbg 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 card type is indicated in the sensor description. Currently, the following cards are supported by mbg:

GPS170PCI

3.3V/5V 6-channel GPS receiver card

PCI32

5V DCF77 time signal station receiver card

PCI509

5V DCF77 time signal station receiver card

PCI511

3.3V/5V DCF77 time signal station receiver card

PEX511

PCI Express DCF77 time signal station receiver card

PZF180PEX

PCI Express DCF77 time signal station receiver card

The quality of the timedelta is reported as the sensor status:

UNKNOWN

No valid time information has been received yet.

OK

The time information is valid and the timedelta is safe to use for applications like ntpd(8).

WARN

The time information is still valid, but no new time information has been decoded for twelve hours (four days in the case of a GPS170PCI card) due to a reception or parity error. The timedelta should be used with care.

CRITICAL

No valid time information has been received for more than twelve hours (or four days in the case of a GPS170PCI card) 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 device itself:

OK

The clock is synchronized.

WARN

The device’s clock is free running on the local oscillator. For DCF77 receiver cards this is not an error and can happen due to the nature of the signal transmission using longwave radio.

CRITICAL

Hardware failure, e.g. communication with the device failed.

SEE ALSO #

intro(4), pci(4), ntpd(8), sysctl(8)

HISTORY #

The mbg driver first appeared in OpenBSD 4.1.

AUTHORS #

The mbg driver was written by Marc Balmer <mbalmer@openbsd.org>.

OpenBSD 7.5 - September 25, 2023