arinc_664_ede_support完整原版文档.docx

ARINC664/AFDX?

EDEsupport

MX-Foundation4APIMAXIMAIRGUI

TECHNOLOGIES

TECHNOLOGIES

Version2.1

PAGE

PAGE13

TableofContents

-AFDX/EDE 3

I-1.AFDXframelayout 3

…….………I-2.EDEMessageformat……………….…………

…

….

…

…

…

-MX-Foundation4-API 7

II-1.WorkwithAFDXonMX-Foundation4 7

II-2.WorkwithAFDX-EDEonMX-Foundation4 9

II-2.a.EDEsupportinAFDXCOMmode 10

II-2.b.EDEerrordetectionsupportinAFDXCOMmode………… 12

II-2.c.EDEsupportinRawmode…… 13

-MAXIMAIR 14

Conclusion 15

-AFDX/EDE

AFDXisanavionicsprotocolsupportedbyMAXTechnologies.

AFDXisaprotocoloverEthernetwithaddedsecuritytoavoiddatacollisionsandreachadeterministicformofEthernet.

AsAFDXisoverEthernet,somespecificationsofAFDXaresimilartotheonesforregularEthernet.EDEisafeatureaddedtoAFDXtoenhancethecommunicationreliability.

Thissectionsgoalistoclarifysomeofthemostimportantpointsofhowframesarebuilt.

-1.AFDXframelayout

AsshowninFigure1,theAFDXMessage(Payload)isencapsulatedin3mainotherlayers:

UDPlayer

IPlayer

MAClayer(headerandfooter)

PAYLOAD

PAYLOAD

UDPPAYLOAD

UDP

PAYLOAD

IPUDPPAYLOAD

IP

UDP

PAYLOAD

MACheaderIPUDPPAYLOAD

MAC

header

IP

UDP

PAYLOAD

MAC

footer

Figure1-Messageencapsulation

Eachlayerisreservedfordefinedfields.Onlymainfieldsaredetailedbelow.

#UDP:8bytes

UDPsourceport:Portusedbythesendingunit

UDPdestinationport:Porttobeusedbythereceivingunit

#IP:20bytes

IPsource:IPaddressoftheunitsendingtheframe

IPdestination:IPaddressoftheunitthathastoreceive

Fragmentation:AnIPDatagramcanbefragmentedintomultiplepackets,forexample,whenthemessagesizeistoolongforonedatagram.Ifthemessageisfragmented,aflagisraisedintheIPlayer.

Length:Sizeinbytesof[IP+UDP+Message]

#MACHeader:14bytes

MACsource:MACaddressofthesen