MICROCHIP PTP Calibration Configuration Guide

Mawu Oyamba

Kalozera kasinthidwe kameneka kamapereka chidziwitso chamomwe mungapangire ma calibrations a Port-to-port ndi 1PPS kuti muwongolere nthawi mwakusintha ma ingress/egress latencies.

Kufotokozera Kwazinthu

Kulimbikira kwa Zotsatira za Calibration
Zotsatira zoyeserera zomwe zafotokozedwa pansipa zimasungidwa kuti ziwonekere kuti zikhalebebe ngakhale chipangizocho chikuyendetsedwe ndi mphamvu kapena kuyambiranso.

Kulimbikira kutsegulanso-zosasintha

Zotsatira zoyeserera zomwe zalongosoledwa pansipa zimakhala zopitilira muyeso wokhazikika. Ngati kuyikanso-zosakhazikika kudzakhazikitsanso zosintha kukhala zosasintha zomwe zamangidwa, izi ziyenera kufotokozedwa ngati gawo kuti mutsegulenso zolakwika, mwachitsanzo:

Kusintha Mwadzidzidzi kwa Timestamp Ndege Reference

CLI imakhala ndi lamulo lomwe limayesa kusiyana kwa T2-T1 kwa doko la PTP mu loopback mode ndiyeno imangosintha egress ndi ingress latencies ya doko kuti T2 ndi T1 zikhale zofanana. Kulinganiza kochitidwa ndi lamulo ili ndi njira yokhayo yomwe doko lidakonzedwa kuti liziyenda. Kuti muyesere mitundu yonse yothandizidwa ndi doko, lamuloli liyenera kubwerezedwa pamachitidwe aliwonse.

Syntax ya lamulo ndi:

Kusankha 'ext' kumatanthawuza kuti loopback yakunja ikugwiritsidwa ntchito. Njira ya 'int' ikagwiritsidwa ntchito, doko lidzakonzedwa kuti likhale loopback yamkati.
Zindikirani: Kwa makina omwe ali ndi kusintha kwakukulu kwa kusinthika kwa latency (osalipidwa serial-to-parallel barrel shifter position) kusinthasintha kumachepetsa ulalowo kangapo kuonetsetsa kuti kuwongolera kwachitika pamtengo wapakati (osati phindu) .

Kusintha kwa doko kupita ku doko
CLI ili ndi lamulo lowongolera doko la PTP pokhudzana ndi doko lina la PTP (doko lolozera) losinthira komweko. Kulinganiza kochitidwa ndi lamulo ili ndi njira yokhayo yomwe doko lidakonzedwa kuti liziyenda. Kuti muyesere mitundu yonse yothandizidwa ndi doko, lamuloli liyenera kubwerezedwa pamachitidwe aliwonse.

Syntax ya lamulo ndi:

Chitsanzo cha akapolo a PTP chokhudzana ndi doko lomwe likuyendetsedwa liyenera kuyendetsa muyeso kuti palibe zosintha zomwe zikuchitika pa nthawi ya PTP. Njira yosinthira imayeza kusiyana kwa T2-T1 ndi T4-T3 ndikuganiziranso za latency ya chingwe kupanga zosintha izi:

1. Sinthani ingress latency ya doko ndi T2-T1-cable_latency
2. Sinthani egress latency padoko ndi T4-T3-cable_latency

Zindikirani: Kwa machitidwe omwe ali ndi kusiyana kwakukulu kwa maulalo-to-linkup latency kusiyana (osalipidwa serial-to-parallel barrel shifter position) kuwerengetsa kumachepetsa ulalowo kangapo kuti kuwonetsetsa kuti kuyesedwa kwachitika pamtengo wapakati (osati mtengo).

Kuwongolera ku Reference Yakunja pogwiritsa ntchito 1PPS

CLI imakhala ndi lamulo lowongolera doko la PTP potengera mawonekedwe akunja pogwiritsa ntchito chizindikiro cha 1PPS. Kulinganiza kochitidwa ndi lamulo ili ndi njira yokhayo yomwe doko lidakonzedwa kuti liziyenda. Kuti muyesere mitundu yonse yothandizidwa ndi doko, lamuloli liyenera kubwerezedwa pamachitidwe aliwonse.
Syntax ya lamulo ndi:

Njira ya synce imapangitsa doko loyang'anira kutseka mawotchi ake pafupipafupi pogwiritsa ntchito SyncE. Monga gawo la njira yosinthira, chitsanzo cha akapolo a PTP cholumikizidwa ndi doko loyang'aniridwa chidzatseka gawo lake pazambiri. Kapolo wa PTP akatsekedwa kwathunthu ndikukhazikika, kuwongolera kumayesa kuchedwa kwa njira ndikupanga zosintha izi:

1. Ingress latency = Ingress latency + (MeanPathDelay - cable_latency)/2
2. Egress latency = Egress latency + (MeanPathDelay - cable_latency)/2

Zindikirani: Kutsatira kuwongolera bwino, kuchedwa kwa njira kudzakhala kofanana ndi kuchedwa kwa chingwe.
Zindikirani: Kwa machitidwe omwe ali ndi kusiyana kwakukulu kwa maulalo-to-linkup latency kusiyana (osalipidwa serial-to-parallel barrel shifter position) kuwerengetsa kumachepetsa ulalowo kangapo kuti kuwonetsetsa kuti kuyesedwa kwachitika pamtengo wapakati (osati mtengo).

Kuwongolera kwa 1PPS skew
Lamulo la 'ptp cal port' (pamwambapa) limalinganiza doko la PTP kuti likhale lakunja pogwiritsa ntchito 1PPS. Kuwongolera uku sikumaganiziranso kuchedwa kwa chizindikiro cha 1PPS padoko loyang'aniridwa. Kuti kutulutsa kwa 1PPS kwa chipangizocho kufanane ndi 1PPS ya kalozera, kuyezetsa kumayenera kulipidwa chifukwa cha 1PPS skew. CLI ili ndi lamulo losintha mawonekedwe a doko la 1PPS yotulutsa skew. Kulinganiza kochitidwa ndi lamulo ili ndi njira yokhayo yomwe doko lidakonzedwa kuti liziyenda. Kuti muyesere mitundu yonse yothandizidwa ndi doko, lamuloli liyenera kubwerezedwa pamachitidwe aliwonse.
Syntax ya lamulo ndi:

• ptp cal port kuchepetsa

Zindikirani: Kwa machitidwe omwe ali ndi kusiyana kwakukulu kwa maulalo-to-linkup latency kusiyana (osalipidwa serial-to-parallel barrel shifter position) kuwerengetsa kumachepetsa ulalowo kangapo kuti kuwonetsetsa kuti kuyesedwa kwachitika pamtengo wapakati (osati mtengo).

1PPS Input Calibration

CLI imakhala ndi lamulo losintha mawerengedwe a doko pakuchedwa kwa 1PPS.
Syntax ya lamulo ndi: 

• ptp ku 1pps

Musanapereke lamuloli, zotulutsa za 1PPS ziyenera kulumikizidwa ndi zolowetsa za 1PPS pogwiritsa ntchito chingwe chochedwa chodziwika. Chingwecho chizikhala chachifupi momwe zingathere. Lamuloli lithandizira kutulutsa kwa 1PPS ndi samplembani nthawi ya LTC pakulowetsa kwa 1PPS. The sampNthawi ya LTC yotsogozedwa ikuwonetsa kuchedwa kumapangidwa motere: Kuchedwa kwa 1PPS kutulutsa + kuchedwa kwa 1PPS + Kuchedwa kwa Cable Kuchedwa kwa 1PPS kumatulutsa nthawi zambiri kumakhala mumtundu wa 1 ns. Kuchedwa kwa 1PPS kuyenera kuwerengedwa ndikusungidwa kuti mudzagwiritse ntchito pambuyo pake PTP ikugwiritsa ntchito 1PPS.

Mapeto a Document.

Zolemba / Zothandizira

MICROCHIP PTP Calibration Configuration Guide [pdf] Buku Logwiritsa Ntchito PTP Calibration Configuration Guide

Maumboni

• Buku Logwiritsa Ntchito