1. Synopsis

Name: neoclock
Reference ID: neol
Serial Port: /dev/neoclock4x-u

2. Warning

This driver reports only two-digit years, and is thus reliant on the system clock to be near correct before samples will be processed properly. You will not be able to use it to run autonomously, nor will it reliably recover from a trashed or zeroed system clock.

3. Description

The refclock_neoclock4x driver supports the NeoClock4X receiver available from Linum Software GmbH. The receiver is available as a DCF77 or TDF receiver. Both receivers have the same output string. For more information about the NeoClock4X receiver please visit http://www.linux-funkuhr.de.

4. Driver Options

time1 time

Specifies the time offset calibration factor with the default value of 0.16958333 seconds. This offset is used to correct serial line and operating system delays incurred in capturing time stamps. If you want to fudge the time1 offset ALWAYS add a value of 0.16958333. This is necessary to compensate for the delay that is caused by transmitting the timestamp at 2400 Baud. If you want to compensate the delay that the DCF77 or TDF radio signal takes to travel to your site simply add the needed millisecond delay to the given value. Note that the time here is given in seconds.

Default setting is 0.16958333 seconds.

time2 time

Not used by this driver.

flag1 {0 | 1}

When set to 1 the driver will feed ntp with timestamps even if the radio signal is lost. In this case an internal backup clock generates the timestamps. This is ok as long as the receiver is synced once since the receiver is able to keep time for a long period.

Default setting is 0 = don’t synchronize to CMOS clock.

flag2 {0 | 1}

You can allow the NeoClock4X driver to use the quartz clock even if it is never synchronized to a radio clock. This is usually not a good idea if you want preceise timestamps since the CMOS clock is maybe not adjusted to a dst status change. So PLEASE switch this only on if you now what you’re doing.

Default setting is 0 = don’t synchronize to unsynchronized CMOS clock.

flag3 {0 | 1}

Not used by this driver.

flag4 {0 | 1}

It is recommended to allow extensive logging while you setup the NeoClock4X receiver. If you activate flag4 every received data is logged. You should turn off flag4 as soon as the clock works as expected to reduce logfile cluttering.

Default setting is 0 = don’t log received data and converted utc time.


Not used by this driver.


Not used by this driver.

path filename

Overrides the default device path.

ppspath filename

Not used by this driver.

baud number

Overrides the default baud rate.

5. Configuration Example

refclock neoclock

6. Author

Please send any comments or question to neoclock4x@linum.com.

icons/home.gif Home Page

icons/sitemap.png Site Map

icons/mail2.gif Contacts