Re: [ntp:questions] proprietary hardware clock as NTP reference source
On Jun 13, 12:21 am, Rob Neal hun...@comcast.net wrote: On Fri, Jun 11, 2010 at 02:26:13PM -0700, apobrien wrote: Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. TIA! Andy ___ questions mailing list questi...@lists.ntp.org http://lists.ntp.org/listinfo/questions Symmetricomm has a kernel mode driver for the bc635/7 cards, for Linux. If you have a copy you can use ntp reference clock 22 (bancomm) to feed the time to NTP refclock 127.127.16.u mode 2 in the config file, where u is whatever unit your card presents as. The Symmetricom driver is proprietary, they charge for it, btw. Thanks Rob, both for updating the driver and for alerting me to its existence. It's exactly what I was looking for. For those interested, here are the steps I followed to get it working using Symmetricom's newer Linux software development kit (SDK). These instructions reference ntp-4.2.6p2-RC6. 1) install the SDK by following their documentation. Copy the shared library file, libbcsdk.so, to a standard directory (I used /usr/lib/ libbcsdk.so) 2) link the default SDK device file to the file expected by the Bancomm reference clock driver: ln -s /dev/windrvr6 /dev/btfp0 3) untar the ntp source and modify ntpd/Makefile.am line 91 from ntpd_LDADD = $(LDADD) $(LIBOPTS_LDADD) ../libntp/libntp.a -lm @LCRYPTO@ @LSCF@ to ntpd_LDADD = $(LDADD) $(LIBOPTS_LDADD) ../libntp/libntp.a -lm - lbcsdk @LCRYPTO@ @LSCF@ 4) configure the source with the --enable-BANCOMM option. I used ./ configure --enable-BANCOMM --enable-clockctl 5) make, make install. If it doesn't compile complaining about MOD_NANO, add the line #define MOD_NANO ADJ_NANO somewhere in ntpd/ntp_loopfilter.c 6) edit ntp.conf as Rob suggests: I'm using server 127.127.16.0 prefer mode 2 burst minpoll 4 After only a few minutes of operation the timing card and system clock average only 2 microseconds disagreement with a [-0.46, 0.000137] range over 1,500,000 samples taken over a ~5 second interval! Thanks Rob! ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] proprietary hardware clock as NTP reference source
On Sun, Jun 13, 2010 at 04:21:58AM +, Rob Neal wrote: On Fri, Jun 11, 2010 at 02:26:13PM -0700, apobrien wrote: Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. TIA! Andy ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions Symmetricomm has a kernel mode driver for the bc635/7 cards, for Linux. If you have a copy you can use ntp reference clock 22 (bancomm) to feed the time to NTP refclock 127.127.16.u mode 2 in the config file, where u is whatever unit your card presents as. The Symmetricom driver is proprietary, they charge for it, btw. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions ur, refclock 16 is bancomm, not 22, sorry. 22 is the ATOM driver. Sorry for the confusion. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] proprietary hardware clock as NTP reference source
On Fri, Jun 11, 2010 at 02:26:13PM -0700, apobrien wrote: Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. TIA! Andy ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions Symmetricomm has a kernel mode driver for the bc635/7 cards, for Linux. If you have a copy you can use ntp reference clock 22 (bancomm) to feed the time to NTP refclock 127.127.16.u mode 2 in the config file, where u is whatever unit your card presents as. The Symmetricom driver is proprietary, they charge for it, btw. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
[ntp:questions] proprietary hardware clock as NTP reference source
Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. TIA! Andy ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] proprietary hardware clock as NTP reference source
In article 40aa2d27-9826-4948-a405-e5b311358...@z8g2000yqz.googlegroups.com, apobrien apobriens...@gmail.com writes: Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. TIA! Andy I think you have two choices. One is to write a stand alone program that talks to your hardware and puts the info into shared memory where the shared-memory driver (driver 28) can get it. gpsd works this way. The other is to write your own refclock-driver. The usual approach is to find a driver that is as close as you can get and modify it. If your changes are small and don't break the old moce, you may be able to convince the ntp project to merge them into the main source package. It may be tricky to get started this way. The best documentation is to read the code. There is some overview here, but it probably won't help much until you look at the code: http://www.cis.udel.edu/~mills/ntp/html/howto.html -- These are my opinions, not necessarily my employer's. I hate spam. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] proprietary hardware clock as NTP reference source
On 2010-06-11, apobrien apobriens...@gmail.com wrote: Hello list, I have a set of proprietary hardware timing cards (Symmetricom bc635PCIe) which synchronize their clocks using a dedicated interconnect. As you might imagine the timing card conditioned time drifts from that of the hosts they're installed in. What I'd like to do is make the master timing card's time into a NTP reference clock then use NTP to distribute that time to the other hosts in the (private) network. I've looked at Orphan mode and undisciplined local clocks but they only refer to the host's software clock if I'm not mistaken. I've also searched through the archive but I'm afraid I lack the appropriate terminology to get meaningful results. Can someone point me toward (some google words maybe) creating an arbitrary NTP reference source (under Linux)? I think I'm just missing something very basic. I've been looking at the LinuxPPS project as these cards output a PPS that I might use to condition the host clock using Linux PPS but I don't have a 8250 serial port on these new fangled PCs. Use shmpps. It uses the shm driver to input the PPS to ntp. It requires that you have some other source to derive the seconds from (I, PPS can allow ntp to condition to the exact second, but has no idea which second it is conditioning to) That serial port is used to input the PPS and the seconds. How would you input the PPS in your case? TIA! Andy ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
