Instruction Manual

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GNAV540UserManual
7430‐0808‐01Rev.B
Page69
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ThiscommandperformsacoreCPUreset,functionallyequivalenttoapowercycle.Alldefaultpower‐upfield
settingswillapply.Theunitwillrespondwithsoftwareresetresponsebeforethesystemgoesdown.
SoftwareResetResponse
Table23SoftwareResetResponse
SoftwareReset(‘SR’=0x5352)
Preamble PacketType Length  Termination
0x5555 0x5352 0x00 <CRC(U2)>
Theunitwillsendthispacketinresponsetoasoftwareresetcommand.
CalibrateCommand
Table24CalibrateCommand
Calibrate(‘WC’=0x5743)
Preamble PacketType Length  Payload Termination
0x5555 0x5743 0x02 <WCpayload> <CRC(U2)>
ThiscommandallowstheusertoperformvariouscalibrationtaskswiththeGNAV540unit.Seethecalibration
commandtablebelowfordetails.Theunitwillrespondimmediatelywithacalibrateresponsecontainingthe
calibrationRequest receivedoranerrorresponseifthecommandcannotbeperformed.
Table25WCPayload
WCPayloadContents
Byte
ffset
O
Name Format Scaling Units Description
0 calibrationRequest U2 — — Therequestedcalibrationtask
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Currently,magneticalignmentistheonlyfunctionsupportedbythecalibratecommand.Therearetwomagnetic
alignmentproceduressupported;(1)magneticalignmentwithautomaticyawtrackingtermination,andmagnetic
alignmentwithoutautomatictermination.
Table26MagneticAlignment
calibrationRequest Description
0x0009 Beginmagneticalignmentwithoutautomatictermination.
Rotatevehiclethrough>360degreesyawandthensend0x000B
calibrationrequestfortermination.
0x000B
Terminatemagneticalignment.TheunitwillsendaCCrespons
containingthehard‐ironandsoft‐ironvalues.
e
Toaccepttheparameters,storethemusingthewritemagnetic
calibrationcommand.
0x000C
Beginmagneticcalibrationwithautomatictermination.Rotatetheunit
through380degreesinyaw.
oft‐iron
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TheunitwillsendaCCresponsecontainingthehard‐ironands
valuesuponcompletionoftheturn.
Toaccepttheparameters,storethemusingthewritemagnetic