Instruction Manual

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GNAV540UserManual
7430‐0808‐01Rev.B
Page71
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ErrorResponse
Table31ErrorResponse
ErrorResponse(ASCIINAK,NAK=0x1515)
Preamble PacketType Length  Payload Termination
0x5555 0x1515 0x02 <NAKpayload> 2)><CRC(U
T
c
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heunitwillsendthispacketinplaceofanormalresponsetoafailedInputPacketType requestifitcouldnotbe
ompletedsuccessfully.
NAKPayloadContents
Byte
ffset
O
Name Format Scaling Units Description
0 failedInputPacketType U2 — — thefailedrequest
OutputPackets(Polled)
ThefollowingpacketformatsarespecialinformationalpacketswhichcanberequestedusingtheGPcommand.
IdentificationDataPacket
Table32IDDataPacket
IdentificationData(‘ID’=0x4944)
Preamble PacketType Length Payload Termination
0x5555 0x4944 <ID <CRC(U2)>5+N payload>
ThispacketcontainstheunitserialNumberandmodelString.Themodelstringisterminatedwith0x00.Themodel
stringcontainstheprogrammed
versionString(8‐bitASCIIvalues)followedbythefirmwarepartnumberstring
delimitedbyawhitespace.
Table33IDPayloadContents
IDPayloadContents
Byte
ffset
O
Name Format Scaling Units Description
0 serialNumber U4 — — Unitserialnumber
4 modelString SN — — UnitVersionString
4+N 0x00 U1 — — ZeroDelimiter
VersionDataPacket
Table34VersionDataPKT
VersionData(‘VR’=0x56 52)
Preamble PacketType Length  Payload Termination
0x5555 0x5652 5 <VRpayload> <CRC(U2)>