Problem solved. Seems because I neglect changing "ident" string in kernel config file, so PPS_SYNC option isn't enabled in effect. These are the steps I followed to recompile the kernel: # cd /usr/src/sys/i386/conf # cp GENERIC PPSGENERIC # ee PPSGENERIC ... add options PPS_SYNC ... [ the only modification ] # cd /usr/src # make buildkernel KERNCONF=PPSGENERIC # make installkernel KERNCONF=PPSGENERIC # shutdown -r now
This does not bring PPS_SYNC into effect, am I right? At least, after I change the "ident GENERIC" to "ident PPSGENERIC" in PPSGENERIC file, ntptime returns pplsignal, pplfreq, and ppltime. --- On Fri, 4/23/10, Chaofu Chen <chaofu.c...@yahoo.com> wrote: > From: Chaofu Chen <chaofu.c...@yahoo.com> > Subject: How to debug PPS? > To: questions@lists.ntp.org > Date: Friday, April 23, 2010, 12:22 AM > Hi all. I want to build a NTP server > but PPS doen't work for the time being. Status bits from > "ntptime" and "ntpdc -c kern" include PLL and NANO, > sometimes PPSTIME and PPSFREQ, but PPSSIGNAL never appears. > > ------- system overview --------------- > MotherBoard: Intel Atom N270 / Intel 945GSE+ICH7M > OS: FreeBSD 7.2R, kernel recompiled with option PPS_SYNC > NTP: v4.2.6p1 > PPS: -8.6v ~ +7.7v, 1Hz, pulse width 500ms > Time source: GGA sentense from GPS module, 9600bps, through > cuad0 > ------- ntp.conf ------------- > server 127.127.20.1 mode 18 prefer > fudge 127.127.20.1 flag1 1 flag2 1 flag3 1 > ... > -------- output of ntpq ---------------------- > ntpq>pe > remote > refid st t when poll > reach delay offset > jitter > ============================================================================== > *GPS_NMEA(1) .GPS. > 0 > l 53 64 377 > 0.000 -4.503 8.626 > ntpq>as > ind assid status conf reach auth condition > last_event cnt > =========================================================== > 1 18533 > 9644 yes yes > none sys.peer reachable 4 > ntpq>rv > associd=0 status=042d leap_none, sync_uhf_radio, 2 events, > kern, > version="ntpd 4.2....@1.2158-o Thu Apr 22 13:28:36 UTC 2010 > (1)", > processor="i386", system="FreeBSD/7.2-RELEASE", leap=00, > stratum=1, > precision=-18, rootdelay=0.000, rootdisp=13.349, > refid=GPS, > reftime=cf7ad712.6e321a44 Thu, Apr 22 2010 > 22:09:22.430, > clock=cf7ad712.7f655c3a Thu, Apr 22 2010 > 22:09:22.497, peer=18533, tc=6, > mintc=3, offset=-4.111, frequency=-4.879, > sys_jitter=7.301, > clk_jitter=0.000, clk_wander=0.006 > ntpq>cv > associd=0 status=0000 , no events, clk_unspec, > device="NMEA GPS Clock", > timecode="$GPGGA,140929,3130.8506,N,10444.6118,E,1,09,0.9,529.2,M,-32.4,M,,*60", > poll=17, noreply=0, badformat=0, baddata=0, > fudgetime1=0.000, stratum=0, > refid=GPS, flags=5 > ---------- output of ntpdc -c kern ------- > pll offset: > -0.00395776 s > pll frequency: -4.879 ppm > maximum error: 0.032849 s > estimated error: 0.003847 s > status: > 2007 pll ppsfreq ppstime nano > pll time constant: 6 > precision: 1e-09 > s > frequency tolerance: 496 ppm > ---------- output of ntptime ----------- > ntp_gettime() returns code 5 (ERROR) > time cf7ad741.5a770bb0 Thu, Apr 22 2010 > 22:10:09.353, (.353379029), > maximum error 36849 us, estimated error 3847 us, TAI > offset 0 > ntp_adjtime() returns code 5 (ERROR) > modes 0x0 (), > offset -3926.940 us, frequency -4.879 ppm, interval > 1 s, > maximum error 36849 us, estimated error 3847 us, > status 0x2007 (PLL,PPSFREQ,PPSTIME,NANO), > time constant 6, precision 0.001 us, tolerance 496 > ppm, > --------------------------------------------------- > > Any suggestions or help will be appreciated. > > > > > _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions