Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread David J Taylor
Yep, I have no issues reading NMEA data from any of the sources I've tried using other code we're developing and also with terminal emulators like putty and hyperterm. OK, Darren, but I would still like to know whether Visual GPS works, just for interest. I understand this to be the case, b

Re: [ntp:questions] NTP 4.2.6p4 Released

2011-09-27 Thread David J Taylor
"NTP Public Services Project" wrote in message news:e1r8zlk-0007wf...@mail.kostecke.net... Redwood City, CA - 2011/09/23 - The NTP Public Services Project (http://support.ntp.org/) is pleased to announce that NTP 4.2.6p4, a Point Release of the NTP Reference Implementation from the NTP Project,

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Darren Long
OK, I've hooked the Ublox6 up to a Debian box and I guess I've been wrong when I've described the interface as a USB-UART. In fact, its using the cdc_acm driver, the "Abstract Control Model driver for USB modems and ISDN adapters", although the device /dev/ttyACM0 is showing up as a character d

Re: [ntp:questions] NTP 4.2.6p4 Released

2011-09-27 Thread Chuck Swiger
On Sep 27, 2011, at 10:42 AM, Richard B. Gilbert wrote: >> * Backported several fixes for Coverity warnings from ntp-dev > > WTF is "Coverity"? My dictionary does not list it! http://lmgtfy.com/?q=Coverity It's a code analysis tool which looks for software bugs. Regards, -- -Chuck

Re: [ntp:questions] NTP 4.2.6p4 Released

2011-09-27 Thread Richard B. Gilbert
On 9/27/2011 11:13 AM, NTP Public Services Project wrote: Redwood City, CA - 2011/09/23 - The NTP Public Services Project (http://support.ntp.org/) is pleased to announce that NTP 4.2.6p4, a Point Release of the NTP Reference Implementation from the NTP Project, is now available at http://www.ntp

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Long, Darren
> -Original Message- > From: Dave Hart [mailto:daveh...@gmail.com] > The GetFileType documentation points out that a return value of > FILE_TYPE_UNKNOWN (== 0) means either the function failed, or the type > of the handle is unknown, and one must call GetLastError() to know > which. I sug

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Long, Darren
> -Original Message- > From: Dave Hart [mailto:daveh...@gmail.com] Thanks for the response Dave, I was hoping you'd show up :) Just a quick reply from me now. > You can't get a break, can you? I'm curious what role the GPS > emulator is playing here. Why not use the D72 directly? I

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Dave Hart
On Tue, Sep 27, 2011 at 11:03 UTC, Darren wrote: > I tried asking about my problems on the IRC channel #ntp last night but got > no response so I thought I'd try the questions list. Sorry I missed you there. On the other hand, now there's a web-searchable record of your troubles that might help s

[ntp:questions] [ntp:announce] NTP 4.2.6p4 Released

2011-09-27 Thread NTP Public Services Project
Redwood City, CA - 2011/09/23 - The NTP Public Services Project (http://support.ntp.org/) is pleased to announce that NTP 4.2.6p4, a Point Release of the NTP Reference Implementation from the NTP Project, is now available at http://www.ntp.org/downloads.html and http://support.ntp.org/download. Fi

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Dave Hart
2011/9/27 Miguel Gonçalves : > 2011/9/27 Dave Hart >> >> I think you're simply confused.  The FreeBSD sysctl you modified isn't >> adjusting the TSC frequency.  It's adjusting FreeBSD's estimate of the >> TSC frequency.  I stand by my understanding that a positive frequency >> compensation reporte

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Long, Darren
> -Original Message- > Darren, > > I can't help with the second query, and only make suggestions for the > first query. I have run serial NMEA devices on XP, with > various versions > on NTP. I've tested both real serial ports, and one Sitecom > serial-over-USB connection. As far as

Re: [ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread David J Taylor
So, I'd appreciate any help with the two issues that I've summarised below: 1) I don't seem to be able to get ntpd to receive NMEA data from any NMEA source I have available on Win XP, despite having success on Linux (this also validates my config entries as correct). [] Cheers, Darren Da

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Thomas Laus
On 2011-09-27, Miguel Gon?alves wrote: > One had 180 ppm sand the other 46 ppm without fiddling with machdep.tsc_freq > sysctl variable. After the correction I am getting -0.041 ppm for the first > and -0.045 ppm for the second. > > > Embedded machines running NanoBSD and they don't do anything el

[ntp:questions] Problems with NMEA refclocks, Ublox6 GPS, on WinXP with 4.2.7p21 4

2011-09-27 Thread Long, Darren
Hi all, I tried asking about my problems on the IRC channel #ntp last night but got no response so I thought I'd try the questions list. I'm trying to use a pure NMEA refclock (no PPS) on Win XP but I'm not having any joy. I've been trying with 4.2.7p214 and tested briefly with 4.2.6p4 to see if

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Miroslav Lichvar
On Tue, Sep 27, 2011 at 10:20:57AM +0100, David Woolley wrote: > Richard B. Gilbert wrote: > > > > >I don't believe that accuracy of 1 microsecond , or less, is > >obtainable without without installing a GPS Timing Receiver or an > >atomic clock of some sort. > > He asked for an offset of 1 micro

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Miroslav Lichvar
On Mon, Sep 26, 2011 at 02:29:42PM +0100, Miguel Gonçalves wrote: > So... I was getting around 180 ppm frequency offset in /etc/ntp.drift and > this value also appeared in loopstats file. > > I checked the machdep.tsc_freq value (this is estimated at boot but can be > changed after the boot comple

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Miguel Gonçalves
On 27 September 2011 10:35, David Woolley wrote: > Applying a static correction to the clock frequency only helps if the > static error is close to or greater than 500ppm. However, if that is the > case, the right thing to do is to replace the motherboard, with a better one > as it is likely tha

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread Miguel Gonçalves
On 27 September 2011 01:29, unruh wrote: > Any(?) gps receiver which has PPS output does better than 1us. Any > network does much worse than 1 us ( more like 10s of us to hundreds). > I might be wrong but checking for instance the Garmin 18 LVC specifications (http://www8.garmin.com/products/gp

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread David Woolley
Miguel Gonçalves wrote: Besides correcting the CPU clock frequency what can I do to improve the Applying a static correction to the clock frequency only helps if the static error is close to or greater than 500ppm. However, if that is the case, the right thing to do is to replace the mothe

Re: [ntp:questions] Loop Frequency and Offset

2011-09-27 Thread David Woolley
Richard B. Gilbert wrote: I don't believe that accuracy of 1 microsecond , or less, is obtainable without without installing a GPS Timing Receiver or an atomic clock of some sort. He asked for an offset of 1 microsecond (presumably RMS or 90 percentile?), not an accuracy of 1 microsecond.