Facebook yafalitsa zomwe zikuchitika zokhudzana ndi kupanga bolodi la PCIe, kuphatikizapo kukhazikitsidwa kwa wotchi yaying'ono ya atomiki ndi wolandila GNSS. Bolodi lingagwiritsidwe ntchito kukonza magwiridwe antchito a ma seva olumikizana nthawi zosiyanasiyana. Mafotokozedwe, schematics, BOM, Gerber, PCB ndi mafayilo a CAD ofunikira kuti apange bolodi amasindikizidwa pa GitHub. Bolodilo lidapangidwa poyambirira ngati chipangizo chokhazikika, chololeza kugwiritsa ntchito tchipisi ta mawotchi atomu tomwe timakhala pa alumali ndi ma module a GNSS monga SA5X, mRO-50, SA.45s ndi u-blox RCB-F9T. Kupanga matabwa okonzeka kutengera zomwe zakonzedwa kuyambika ndi Orolia.
Time Card ikupangidwa ngati gawo la ntchito yapadziko lonse lapansi ya Time Appliance yomwe cholinga chake ndi kupereka zigawo zopangira ma seva anthawi yeniyeni (Time Master) (Open Time Server), yomwe imatha kuyikidwa muzomangamanga zawo ndikugwiritsa ntchito, mwachitsanzo, kukonza. kulunzanitsa nthawi m'malo a data. Kugwiritsa ntchito seva yosiyana kumakupatsani mwayi kuti musadalire mautumiki akunja akunja kuti mulumikizane ndi nthawi yolondola, komanso kukhalapo kwa wotchi ya atomiki yomangidwa kumapereka mwayi wodziyimira pawokha ngati mukulephera kulandira deta kuchokera ku makina a satana (mwachitsanzo, wotchi ya atomiki yokhazikika) chifukwa cha nyengo kapena kuukira).
Chodabwitsa cha pulojekitiyi ndikuti kupanga seva yoyambira nthawi yeniyeni, mutha kugwiritsa ntchito seva yokhazikika kutengera kapangidwe ka x86, komwe kumaphatikizapo khadi yapaintaneti wamba ndi Time Card. Mu seva yotereyi, chidziwitso cha nthawi yolondola chimalandira kuchokera ku ma satellites kudzera pa GNSS, ndipo wotchi ya atomiki imakhala ngati oscillator yokhazikika kuti ikhale yolondola kwambiri pakalephera kupeza zambiri kudzera pa GNSS. Kupatuka komwe kungatheke kuchokera ku nthawi yeniyeni ngati kulephera kulandira deta kudzera pa GNSS mu bolodi yomwe ikufunsidwa kukuyembekezeka kukhala pafupifupi 300 nanoseconds patsiku.
Kwa Linux, ocp_pt dalaivala yakonzedwa, yomwe ikukonzekera kuphatikizidwa muzolemba zazikulu za Linux 5.15 kernel. Dalaivala amagwiritsa ntchito PTP POSIX (/dev/ptp2), GNSS pa serial (/dev/ttyS7), wotchi ya atomiki pamwamba pa serial (/dev/ttyS8), ndi zida ziwiri za i2c (/dev/i2c-*), pogwiritsa ntchito kufikika ku kuthekera kwa wotchi ya hardware (PHC) kuchokera kumalo ogwiritsa ntchito. Mukayamba seva ya NTP (Network Time Protocol), tikulimbikitsidwa kugwiritsa ntchito Chrony ndi NTPd, komanso poyambitsa seva ya PTP (Precision Time Protocol) - ptp4u kapena ptp4l kuphatikiza ndi phc2sys stack, yomwe imapereka nthawi yotengera nthawi wotchi ya atomiki ku netiweki khadi.
Kugwirizana kwa magwiridwe antchito a wolandila GNSS ndi wotchi ya atomiki zitha kuchitidwa mu hardware ndi mapulogalamu. Magwiridwe a Hardware a module yofananira amakhazikitsidwa pamaziko a FPGA, ndipo mtundu wa pulogalamuyo umagwira ntchito pamlingo wowunika mwachindunji wa wolandila GNSS ndi wotchi ya atomiki kuchokera kumapulogalamu monga ptp4l ndi chronyd.
Zifukwa zopangira bolodi lotseguka m'malo mogwiritsa ntchito mayankho okonzeka pamsika ndi momwe zinthu ziliri, zomwe sizikulolani kutsimikizira kulondola kwa kukhazikitsidwa, kusiyana pakati pa mapulogalamu omwe akufunsidwa ndi zofunikira zachitetezo (zambiri. milandu, mapulogalamu akale amaperekedwa, ndipo kukonza kwachiwopsezo kumatha kutenga miyezi kapena zaka), komanso kuyang'anira kochepa (SNMP) ndi zosankha zosinthira (CLI kapena Web UI yanu imaperekedwa).
Source: opennet.ru