Instruction Manual

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GNAV540UserManual
7430‐0808‐01Rev.B
age68
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InteractiveCommands
InteractivecommandsareusedtointeractivelyrequestdatafromtheGNAV540unit,andtocalibrateorresetthe
unit.
GetPacketRequest
Table18GPRequest
GetPacket(‘GP’=0x4750)
Preamble PacketType Length  Payload Termination
0x5555 0x4750 0x02 <GPpayload> <CRC(U2)>
Thiscommandallowstheusertopollforbothmeasurementpacketsandspecialpurposeoutputpacketsincluding
T0,VR,andID.
Table19GPPayload
GPPayloadContents
Byte
ffset
O
Name Format Scaling Units Description
0 requestedPacketType U2 — — Therequestedpackettype
RefertothesectionsbelowforPacketDefinitionssentinresponsetothe‘GP’command
AlgorithmResetCommand
Table20AlgorithmResetCommand
AlgorithmReset(‘AR’=0x4152)
Preamble PacketType Length  Payload Termination
0x5555 0x4152 0x00 — <CRC(U2)>
ThiscommandresetsthestateestimationalgorithmwithoutreloadingfieldsfromEEPROM.Allcurrentfieldvalues
willremainineffect.Theunitwillrespondwithanalgorithmresetresponse.
AlgorithmResetResponse
Table21AlgorithmResetResponse
AlgorithmReset(‘AR’=0x4152)
Preamble PacketType Length  Termination
0x5555 0x4152 0x00 <CRC(U2)>
Theunitwillsendthispacketinresponsetoanalgorithmresetcommand.
SoftwareResetCommand
Table22SoftwareResetCommand
SoftwareReset(‘SR’=0x5352)
Preamble PacketType Length  Payload Termination
0x5555 0x5352 0x00 — <CRC(U2)>