Re: [ntp:questions] SHM driver as a PPS source

[Brian Inglis]

On 2016-11-24 05:49, folkert wrote:

How can I tell NTPd that an SHM time source is actually a PPS and
that it thus should combine it with some other sources? (an '*' +
'o' combination so to say)


Seems to be implied for paired gpsd SHM regions e.g.

server  127.127.28.0minpoll 4 maxpoll 4
fudge   127.127.28.0refid GPS time1 0.###

server  127.127.28.1minpoll 4 maxpoll 4 prefer
fudge   127.127.28.1refid PPS

Unit 0 is coarse time and output must *follow* closely *after*
unit 1 precise time output to get the correct seconds label.

Seems gpsd may connect /dev/gps0 interrupts to kernel pps and use
that, as it says the system must support kernel pps.

Use ntpshmmon to check SHM contents.

--
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
___
questions mailing list
questions@lists.ntp.org
http://lists.ntp.org/listinfo/questions

Re: [ntp:questions] NTP 4.2.8p9 installer for Windows available

[Martin Burnicki]

Brian Inglis wrote:
> On 2016-11-23 03:28, Martin Burnicki wrote:
>> Brian Inglis wrote:
[...]
> The timestamps are displayed by Cygwin stat(1), and Birth is Windows
> Explorer Creation Date. The signature timestamps agree with the birth
> (creation) times.

Ah, OK.

>> Eventually the DLL couldn't be updated by the installer since it was
>> in use when you installed the update.
> 
> Guess we should shut down NTP before running the installer, rather than
> letting the installer do the shutdown, on a file-only replacement.

Hm, strange. AFAIK the installer should stop the NTP service before the
files are updated, so this shouldn't be an issue.

>> I have to admit that personally I've never used PPS under Windows,
>> so I'm not familiar with this DLL and the modified serial.sys driver
>> which supports PPS.
> 
> Driver serial.sys is (was?) compatible with ISA drivers, but not PCI
> drivers, for which loopback-ppsapi-provider.dll provides the PPS API.
> 
>> IIRC this has been implemented by Dave Hart some years ago, and we
>> (Meinberg) just provide a signed version of the DLL and the kernel
>> driver simplify usage on current Windows versions which require such
>> signatures.
>>
>>> This DLL seems to be the only way to get PPS working
>>> properly with recent (PCI) serial cards and drivers on
>>> recent Windows releases.
>>>
>>> Presumably for security reasons, the full path(s) must be
>>> specified in the PPSAPI_DLLS *SYSTEM* environment variable,
>>> on recent Windows releases.
>>
>> This should be documented somewhere, but I have no idea it there's any
>> documentation for this stuff at all, except on David Taylor's web pages
>> and in some email/newsgroup posts.
> 
> Use of serial.sys is well documented, but loopback-ppsapi-provider.dll, and
> alternative NMEA PPSAPI_HACK are not, and Perly says he may find time to
> document these, after recent fixes.
> 
> PPSAPI_DLLS http://bugs.ntp.org/show_bug.cgi?id=3066#c4
> PPSAPI_HACK http://bugs.ntp.org/show_bug.cgi?id=3066#c11

Thanks for the pointer. Juergen is doing a great job for NTP.

> Thanks to Meinberg, Martin, et. al. for providing these convenient
> installers
> for so many years.
> 
> Thanks also to Harlan Stenn, Juergen Perlinger, Brian Utterback, et. al.
> for
> fixing so many bugs for so long.

Thanks for your thanks! ;-)

Martin

___
questions mailing list
questions@lists.ntp.org
http://lists.ntp.org/listinfo/questions

Re: [ntp:questions] Security announcements

[Jan Ceuleers]

On 24/11/16 04:39, Harlan Stenn wrote:
> Announcements are supposed to be automatically sent to the announce
> list, which should cause them to appear on questions@ and hackers@.
> 
> We'll dig.

Thanks Harlan.
___
questions mailing list
questions@lists.ntp.org
http://lists.ntp.org/listinfo/questions

[ntp:questions] SHM driver as a PPS source

[folkert]

Hi,

How can I tell NTPd that an SHM time source is actually a PPS and that
it thus should combine it with some other sources? (an '*' + 'o'
combination so to say)


Folkert van Heusden

-- 
--
Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com
___
questions mailing list
questions@lists.ntp.org
http://lists.ntp.org/listinfo/questions