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é«å質ã®ã¿ã€ã ãµãŒããŒãã»ããã¢ããããã«ã¯ãGPSDãNTPãããã³ 1PPS (XNUMX ç§ããã XNUMX ãã«ã¹) åºåã® GPS åä¿¡æ©ã®ã¿ãå¿ èŠã§ãã
1. gpsd ãš ntpdããŸã㯠gpsd ãš chronyd ãã€ã³ã¹ããŒã«ããŸãã GPSD ããŒãžã§ã³ã¯ 3.20 以äžã§ããå¿ èŠããããŸã
(1:1109)$ sudo emerge -av gpsd chrony
Local copy of remote index is up-to-date and will be used.
Calculating dependencies... done!
[binary N ] net-misc/pps-tools-0.0.20120407::gentoo 31 KiB
[binary N ] net-misc/chrony-3.5-r2::gentoo USE="adns caps cmdmon ipv6 ntp phc readline refclock rtc seccomp (-html) -libedit -pps (-selinux)" 246 KiB
[binary N ] sci-geosciences/gpsd-3.17-r3:0/23::gentoo USE="X bluetooth cxx dbus ipv6 ncurses python shm sockets udev usb -debug -latency-timing -ntp -qt5 -static -test" GPSD_PROTOCOLS="aivdm ashtech earthmate evermore fv18 garmin garmintxt gpsclock isync itrax mtk3301 navcom ntrip oceanserver oncore rtcm104v2 rtcm104v3 sirf skytraq superstar2 tnt tripmate tsip ublox -fury -geostar -nmea0183 -nmea2000 -passthrough" PYTHON_TARGETS="python2_7" 999 KiB
Total: 3 packages (3 new, 3 binaries), Size of downloads: 1275 KiB
Would you like to merge these packages? [Yes/No]
2. PPS ããµããŒããã GPS åä¿¡æ©ã RS232 ã·ãªã¢ã«ãŸã㯠USB ããŒãã«æ¥ç¶ããŸãã
éåžžã®å®äŸ¡ãª GPS åä¿¡æ©ã¯æ©èœããŸãããé©åãªãã®ãèŠã€ããã«ã¯ãå°ãæ€çŽ¢ããå¿ èŠããããããããŸããã
3. ããã€ã¹ãå®éã« PPS ãçºè¡ããŠããããšã確èªããã«ã¯ãgpsmon ãŠãŒãã£ãªãã£ã§ããŒãããã§ãã¯ããŸãã
4. /etc/conf.d/gpsd ãã¡ã€ã«ãéãã次ã®è¡ãç·šéããŸãã
眮æ
GPSD_OPTIONS=""
ã«ãªãããã«
GPSD_OPTIONS="-n"
ãã®å€æŽã¯ãgpsd ãèµ·åæã«ããã« SRNS ãœãŒã¹ã®æ€çŽ¢ãéå§ããããã«å¿ èŠã§ãã
5. gpsd ãèµ·åãŸãã¯åèµ·åããŸãã
(1:110)$ sudo /etc/init.d/gpsd start
(1:111)$ sudo /etc/init.d/gpsd restart
systemd ã䜿çšãããã£ã¹ããªãã¥ãŒã·ã§ã³ã®å Žåã¯ãé©å㪠systemctl ã³ãã³ãã䜿çšããŸãã
6. cgps ã³ãã³ãã®ã³ã³ãœãŒã«åºåã確èªããŸãã
ããŒã¿ãè¡æããæ£ããåä¿¡ãããŠããããšã確èªããå¿ èŠããããŸãã ã³ã³ãœãŒã«ã«ã¯å³ã®ãããªãã®ã衚瀺ãããã¯ãã§ãã
cgps ã³ã³ãœãŒã« ã³ãã³ãã®åºåã
7. /etc/ntp.conf ãã¡ã€ã«ãç·šéããŸãã
# GPS Serial data reference (NTP0)
server 127.127.28.0
fudge 127.127.28.0 time1 0.9999 refid GPS
# GPS PPS reference (NTP1)
server 127.127.28.1 prefer
fudge 127.127.28.1 refid PPS
å é ã® NTP0 ãšã³ããªã¯ãã»ãŒãã¹ãŠã® GPS ããã€ã¹ã§å©çšã§ããäžçæãœãŒã¹ã瀺ããŸãã äžçªäžã® NTP1 ãšã³ããªã¯ãããæ£ç¢ºãª PPS ãœãŒã¹ãå®çŸ©ããŸãã
8.ntpdãåèµ·åããŸãã
(1:112)$ sudo /etc/init.d/ntpd restart
systemd ã䜿çšãããã£ã¹ããªãã¥ãŒã·ã§ã³ã®å Žåã¯ãsystemctl ã³ãã³ãã䜿çšããŸãã
$ sudo systemctl ntpãåèµ·åããŸã
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