[ntp:questions] help with setting up NTP on windows with a USB GPS

David J Taylor david-taylor at blueyonder.not-this-bit.nor-this-part.co.uk.invalid
Tue Dec 1 06:56:25 UTC 2009

"Dave Baxter" <g8kbv at uko2.co.uk> wrote in message 
news:MPG.257e5228127dac81989680 at news.demon.co.uk...
> Hi.
> I'm also trying to get this working, haveing failed miserably with the
> FreeBSD system (it would never seem to respond to the GPS, and as I
> don't know squat about 'BSD, decided to revert to Winders...)

On reason for me writing my Web page was that I felt a similar level of 
ignorance about FreeBSD, so I hoped it would help.  However, I believe 
some of the port names and perhaps other things have changed in later 
versions of FreeBSD, so if what I wrote doesn't help, then neither can I. 
Windows is getting sub-millisecond for me.

> Anyway, I have a working install of the Meinberg NTPD Windows port on
> Win2k, and it is sync'ing OK to online servers, but they are the trouble
> I'm trying to get round, due to variable and huge BT/ISP induced
> latency, screwing arround with NTP during the weekday, that I use with
> "Faros" a HF Radio propagation beacon monitor.
> Long story short, I'm trying to put together a Stratum 1 time server for
> my LAN only, maybe even on the same physical PC as Faros.
> I had (killed it now) a version of the patched serial.sys for PPS
> support, but it BSOD'd the machine at boot time (black screen) needing a
> physical removal of the hard drive, and temporary fitment into another
> PC to put the original file back.
> At present, I can't find a ready-to-use binary of that file.  Dave
> Hart's site befuddles me, all I can see there is a *Huge* collection of
> files, what file do I need and where from, exactly please.?
> I have a Garmin GPS16LVC with PPS output.  (Two of them, both work fine
> AFAICS, with VisualGPS and a 'scope looking at the PPS signal, that
> needed buffering to RS232 levels.)
> Comments, hints?
> Regards
> Dave Baxter.


You don't need the serialpps.sys except for the ultimate in performance. 
Having said that, it's working here on Windows 2000, Windows XP, and 
Windows-7, and I would be rather surprised if it didn't work on Windows 
Vista as well.  Dave Hart would probably appreciate more details of the 
BSOD failure.

Having installed the most recent Meinberg NTP (Copenhagen), copy the files 
from this archive:


on top of the Meinberg-installed files.  Dave is very helpful in providing 
the recent development builds of NTP, and in case some error is 
introduced, he leaves working versions.  The version I suggested is one I 
am using so I know it's OK.  In each release there is a normal build, a 
build with extra debugging information, and the file containing the 
symbols for each build in case you want to debug the programs by stepping 
through a line at a time - "normal" users would not need to do this.

On my own system, I found that the PPS line worked directly to RS232 
without any buffering, indeed I have a GPS 18 LVC feeding two RS232 ports 
in parallel.  My newer GPS 18x LVC feeds just one RS232 port directly.


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