FR: System Date/Time from Ensemble

[richard-gravy]

Hello,

I did some reading up after noticing how quickly my portable DAB radio obtains the date and time after power on.
The information is transmitted in local time offset, once per second, in Fig 0/10.
Do you think it might be possible to use this as a time source for an NTP server?

I know that there are better solutions available, like receiving MSF or local equivalent, but the thought occurred to me that if you are receiving DAB on an infrastructure device, like a beefy router, it may be useful for more than just audio.

[andimik]

It's similar to AlbrechtL/welle.io#654

[JvanKatwijk]

It is not difficult to put the time on an IP port, such that interested parties could use it. Op zo 13 jun. 2021 om 09:35 schreef andimik ***@***.***>:

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It's similar to AlbrechtL/welle.io#654 <AlbrechtL/welle.io#654> — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#51 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACCPHQDIHB37GPLPKJZZELLTSRNU7ANCNFSM46TA643A> .

-- Jan van Katwijk

[JvanKatwijk]

Just as a gadget I added the possibility to send the time to an IP port (8889 by default). Format (*byes") FF 00 FF 00 (year & 0xFF) >> 8, year& 0xFF, month, dat, minutes, seconds local time Port can be set by command line parameter -C XXX configuring by uncommenting datastreamer as said, it is merely agadget, just to see what was needed to implement such a feature Op zo 13 jun. 2021 om 10:41 schreef jan van katwijk ***@***.***

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: It is not difficult to put the time on an IP port, such that interested parties could use it. Op zo 13 jun. 2021 om 09:35 schreef andimik ***@***.***>: > It's similar to AlbrechtL/welle.io#654 > <AlbrechtL/welle.io#654> > > — > You are receiving this because you are subscribed to this thread. > Reply to this email directly, view it on GitHub > <#51 (comment)>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/ACCPHQDIHB37GPLPKJZZELLTSRNU7ANCNFSM46TA643A> > . > -- Jan van Katwijk

-- Jan van Katwijk

[richard-gravy]

@andimik Pleased that someone else has asked for the same thing in another project, means it's not a terrible idea!

I've just been looking at the "sock" driver for chrony, which is a common NTP daemon on Linux that can be client or server.
In particular, the structure of the data, indicated at https://git.tuxfamily.org/chrony/chrony.git/tree/refclock_sock.c, "struct sock_sample".

Would it be as simple as setting "tv" to the value from the ensemble, set everything else to zero except for the magic number?
Again, it's not practical as a primary reference because you can't interact with the transmission to compensate for drift, but it's better than nothing.