Facebook ya wallafa abubuwan da suka shafi ƙirƙirar allon PCIe, gami da aiwatar da ƙaramin agogon atomic da mai karɓar GNSS. Ana iya amfani da allon don tsara aikin sabar aiki tare na lokaci daban. Ƙididdiga, ƙididdiga, BOM, Gerber, PCB da fayilolin CAD da ake buƙata don samar da jirgi ana buga su akan GitHub. An tsara allon tun asali azaman na'ura mai mahimmanci, yana ba da damar amfani da nau'ikan guntuwar agogon atomic daban-daban da kuma na'urorin GNSS kamar SA5X, mRO-50, SA.45s da u-blox RCB-F9T. Orolia na da niyyar fara samar da allunan da aka yi da shirye-shiryen dangane da ƙayyadaddun da aka shirya.
Ana haɓaka allon katin lokaci a matsayin wani ɓangare na ƙarin aikin kayan aikin lokaci na duniya da nufin samar da abubuwan haɗin gwiwa don ƙirƙirar sabar lokaci na farko (Time Master) ainihin sabar lokaci (Open Time Server), waɗanda za'a iya tura su cikin kayan aikin su kuma ana amfani da su, alal misali, zuwa tsara lokaci aiki tare a cikin bayanai cibiyoyin. Amfani da keɓantaccen uwar garken yana ba ku damar dogaro da sabis na cibiyar sadarwa na waje don ingantaccen aiki tare na lokaci, kuma kasancewar agogon atomic da aka gina a ciki yana ba da babban matakin cin gashin kansa idan aka sami gazawa wajen karɓar bayanai daga tsarin tauraron dan adam (misali. saboda yanayin yanayi ko hare-hare).
Mahimmancin aikin shine don gina ainihin sabar lokaci na farko, zaka iya amfani da sabar na yau da kullum bisa tsarin gine-ginen x86, wanda ya haɗa da katin sadarwa na yau da kullum da Katin Lokaci. A cikin irin wannan uwar garken, ana karɓar sahihan bayanai na lokaci daga tauraron dan adam ta hanyar GNSS, kuma agogon atomic yana aiki azaman oscillator mai tsayi sosai don kiyaye babban matakin daidaito idan aka gaza samun bayanai ta hanyar GNSS. Yiwuwar karkata daga ainihin lokacin idan an gaza samun bayanai ta hanyar GNSS a cikin hukumar da aka tsara ana ƙiyasta kusan nanoseconds 300 kowace rana.
Don Linux, an shirya direban ocp_pt, wanda aka tsara za a haɗa shi cikin babban abun da ke cikin Linux 5.15 kernel. Direba yana aiwatar da PTP POSIX (/ dev/ptp2), GNSS akan serial (/ dev/ttyS7), agogon atomic akan serial (/ dev/ttyS8), da na'urorin i2c guda biyu (/ dev/i2c-*), ta amfani da wanda zai iya a sami damar zuwa damar agogon hardware (PHC) daga mahallin mai amfani. Lokacin fara uwar garken NTP (Network Time Protocol), ana ba da shawarar yin amfani da Chrony da NTPd, kuma lokacin fara sabar PTP (Precision Time Protocol), ptp4u ko ptp4l a hade tare da tari na phc2sys, wanda ke tabbatar da cewa ƙimar lokaci daga agogon atomic ana kwafi zuwa katin cibiyar sadarwa.
Ana iya aiwatar da daidaita aikin mai karɓar GNSS da agogon atomic duka a cikin hardware da software. Ana aiwatar da aikin hardware na tsarin daidaitawa akan FPGA, kuma sigar software tana aiki a matakin sa ido kai tsaye na yanayin mai karɓar GNSS da agogon atomic daga aikace-aikace kamar ptp4l da chronyd.
Dalilan haɓaka allon buɗewa maimakon yin amfani da shirye-shiryen da aka yi a kasuwa shine yanayin mallakar irin waɗannan samfuran, wanda baya ba ku damar tabbatar da daidaiton aiwatarwa, rarrabuwa tsakanin software da aka gabatar da buƙatun tsaro (a mafi yawan lokuta). lokuta, ana ba da shirye-shiryen da ba su daɗe ba, kuma isar da gyare-gyaren rashin lahani na iya ɗaukar watanni ko ma shekaru), kazalika da iyakancewar saka idanu (SNMP) da zaɓuɓɓukan daidaitawa (ana ba da CLI ko Web UI).
source: budenet.ru