[LinuxPPS] ntpd doesn't recognize my PPS signal
Thorsten M.
thenktor at gmx.de
Fri Oct 17 13:40:45 CEST 2008
I guess the problem are the doubled sequence numbers? I've tried TTL and RS232 signals on pps0.
Both give the same result, but the ktimer on pps1 doesn't have the doubled numbers:
root[pps0]# modprobe ktimer
root[pps0]# ppstest /dev/pps0
trying PPS source "/dev/pps0"
found PPS source "/dev/pps0"
ok, found 1 source(s), now start fetching data...
source 0 - assert 1224243426.998519134, sequence: 6385 - clear 1224243426.098752871, sequence: 6381
source 0 - assert 1224243426.998519134, sequence: 6385 - clear 1224243427.098684891, sequence: 6382
source 0 - assert 1224243427.998518138, sequence: 6386 - clear 1224243427.098684891, sequence: 6382
source 0 - assert 1224243427.998518138, sequence: 6386 - clear 1224243428.098754339, sequence: 6383
source 0 - assert 1224243428.998517293, sequence: 6387 - clear 1224243428.098754339, sequence: 6383
source 0 - assert 1224243428.998517293, sequence: 6387 - clear 1224243429.098684606, sequence: 6384
root[pps0]# ppstest /dev/pps1
trying PPS source "/dev/pps1"
found PPS source "/dev/pps1"
ok, found 1 source(s), now start fetching data...
source 0 - assert 1224243432.478640434, sequence: 9 - clear 0.000000000, sequence: 0
source 0 - assert 1224243433.475711658, sequence: 10 - clear 0.000000000, sequence: 0
source 0 - assert 1224243434.482060339, sequence: 11 - clear 0.000000000, sequence: 0
source 0 - assert 1224243435.482061329, sequence: 12 - clear 0.000000000, sequence: 0
source 0 - assert 1224243436.482062550, sequence: 13 - clear 0.000000000, sequence: 0
source 0 - assert 1224243437.475715765, sequence: 14 - clear 0.000000000, sequence: 0
source 0 - assert 1224243438.482064096, sequence: 15 - clear 0.000000000, sequence: 0
On Fri, 17 Oct 2008 12:12:40 +0200
"Thorsten M." <thenktor at gmx.de> wrote:
> Hi
> My ntpd doesnt recognize my PPS signal. Could somebody give me a hint please?
> Here are logs and infos:
>
> 1.
> root[~]# modprobe pps-ldisc
> root[~]# ppsldisc /dev/ttyS1 &
> root[~]# rcntpd restart
>
> output of /var/log/messages:
> Oct 17 11:49:15 (none) kernel: PPS line discipline registered
> Oct 17 11:49:37 (none) kernel: new PPS source serial1 at ID 0
> Oct 17 11:49:37 (none) kernel: PPS source #0 "/dev/ttyS1" added
> Oct 17 11:52:42 (none) ntpd[2816]: ntpd exiting on signal 15
> Oct 17 11:52:48 (none) ntpd[869]: ntpd 4.2.4p5 at 1.1541-o Wed Oct 15 14:28:36 UTC 2008 (1)
> Oct 17 11:52:48 (none) ntpd[870]: precision = 1.000 usec
> Oct 17 11:52:48 (none) ntpd[870]: Listening on interface #0 wildcard, 0.0.0.0#123 Disabled
> Oct 17 11:52:48 (none) ntpd[870]: Listening on interface #1 lo, 127.0.0.1#123 Enabled
> Oct 17 11:52:48 (none) ntpd[870]: Listening on interface #2 eth0, 192.168.18.110#123 Enabled
> Oct 17 11:52:48 (none) ntpd[870]: kernel time sync status 2040
> Oct 17 11:52:48 (none) ntpd[870]: frequency initialized 17.732 PPM from /etc/ntp/drift
> Oct 17 11:52:56 (none) ntpd[870]: synchronized to 192.168.18.120, stratum 1
> Oct 17 11:52:56 (none) ntpd[870]: kernel time sync status change 2001
>
>
> 2.
> root[~]# ppstest /dev/pps0
> trying PPS source "/dev/pps0"
> found PPS source "/dev/pps0"
> ok, found 1 source(s), now start fetching data...
> source 0 - assert 1224237886.995950536, sequence: 910 - clear 1224237886.096114223, sequence: 909
> source 0 - assert 1224237886.995950536, sequence: 910 - clear 1224237887.096116379, sequence: 910
> source 0 - assert 1224237887.995952349, sequence: 911 - clear 1224237887.096116379, sequence: 910
> source 0 - assert 1224237887.995952349, sequence: 911 - clear 1224237888.096118382, sequence: 911
> source 0 - assert 1224237888.995956209, sequence: 912 - clear 1224237888.096118382, sequence: 911
> source 0 - assert 1224237888.995956209, sequence: 912 - clear 1224237889.096122244, sequence: 912
> source 0 - assert 1224237889.995961952, sequence: 913 - clear 1224237889.096122244, sequence: 912
> source 0 - assert 1224237889.995961952, sequence: 913 - clear 1224237890.096126104, sequence: 913
> source 0 - assert 1224237890.995960208, sequence: 914 - clear 1224237890.096126104, sequence: 913
> source 0 - assert 1224237890.995960208, sequence: 914 - clear 1224237891.096128100, sequence: 914
> source 0 - assert 1224237891.995964061, sequence: 915 - clear 1224237891.096128100, sequence: 914
>
>
> 3.
> root[~]# ntpq -p
> remote refid st t when poll reach delay offset jitter
> ==============================================================================
> +192.168.18.60 192.53.103.108 2 u 33 64 377 0.224 -6.692 0.580
> *192.168.18.120 .DCFi. 1 u 39 64 377 0.385 2.483 0.557
> PPS(0) .PPS. 0 l - 16 0 0.000 0.000 0.001
>
>
> 4.
> root[~]# ntptime
> ntp_gettime() returns code 0 (OK)
> time cca2e248.0fa3768c Fri, Oct 17 2008 12:07:04.061, (.061088690),
> maximum error 53814 us, estimated error 1131 us, TAI offset 0
> ntp_adjtime() returns code 0 (OK)
> modes 0x0 (),
> offset 2298.332 us, frequency 17.873 ppm, interval 1 s,
> maximum error 53814 us, estimated error 1131 us,
> status 0x2001 (PLL,NANO),
> time constant 6, precision 0.001 us, tolerance 500 ppm,
>
>
> 5.
> root[~]# ls -l /sys/class/pps/
> insgesamt 0
> drwxr-xr-x 2 root root 0 2008-10-17 11:49 pps0/
>
> root[~]# ls -l /sys/class/pps/pps0/
> insgesamt 0
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 assert
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 clear
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 dev
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 echo
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 mode
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 name
> -r--r--r-- 1 root root 4096 2008-10-17 11:50 path
> lrwxrwxrwx 1 root root 0 2008-10-17 11:50 subsystem -> ../../pps/
> -rw-r--r-- 1 root root 4096 2008-10-17 11:50 uevent
>
> root[~]# ls -l /dev/pps*
> crw-rw---- 1 root root 253, 0 2008-10-17 11:49 /dev/pps0
>
>
> 6.
> root[~]# lsof -n | grep ntp | grep dev
> ntpd 870 root 0u CHR 1,3 43 /dev/null
> ntpd 870 root 1u CHR 1,3 43 /dev/null
> ntpd 870 root 2u CHR 1,3 43 /dev/null
>
>
> 7.
> # /etc/ntp.conf: Configuration file for ntpd.
> server 192.168.18.60 dynamic iburst
> server 192.168.18.120 prefer dynamic iburst
> # atom pps driver
> server 127.127.22.0 minpoll 4 maxpoll 4
> fudge 127.127.22.0 flag2 1
>
>
> 8.
> root[~]# cat /sys/class/pps/pps0/{assert,clear}
> 1224238320.995948448#1344
> 1224238321.096114350#1344
>
>
>
> Greetings
> Thorsten
>
> _______________________________________________
> LinuxPPS mailing list
> LinuxPPS at ml.enneenne.com
> http://ml.enneenne.com/cgi-bin/mailman/listinfo/linuxpps
> Wiki: http://wiki.enneenne.com/index.php/LinuxPPS_support
More information about the LinuxPPS
mailing list