User manual

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 DocumentMT0100P.N
©XsensTechnologiesB.V. MTiandMTxUserManualandTechnicalDocumentation
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5.6 Internalclockaccuracy
TheinternalclockjitteroftheMTiandMTxislessthan25ns.
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TheinternalclockoftheMTiandMTxwhichgeneratesthesampletimingbasedonthesetsampleperiodis
accurate to ±30 ppm over the temperature operating range. In practice this means that the worst case
deviationaftera1hourlogis±0.108seconds(=3600s∙30ppm) or10samplecountsin360,000at100Hz
samplerate(±0.3μs/sample@100Hz).
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NOTE: For long logging times that require synchronization with external clocks or events, means of
synchronizationwithahigh‐precisionexternalclockshouldbeconsidered.
5.7 DefaultSerialConnectionSettings
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Setting DefaultValue
Bits/second(bps): 115200
Databits: 8
Parity: none
Stopbits: 1
(
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)
Flowcontrol: none
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ThesesettingsarethesamefortheRS‐232astheRS‐422versions.Thebaudrate(bps)settingcanbechanged
bytheuser.Themaximumis921600bpsandtheminimum9600bps.PleaserefertotheMTiandMTxLow‐
levelCommunicationDocumentationfordetails.
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5.7.1 Generaldefinitionsforbinarydata
Allbinarydatacommunicationisdoneinbig‐endianformat.
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Example:
Un‐calibrated16bitsaccelerometeroutput
1275(decimal)=0x04FB(hexadecimal)
Transmissionorderofbytes=0x040xFB
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Calibratedaccelerometeroutput(float,4bytes)
9.81(decimal)=0x411CF5C3(hexadecimal)
Transmissionorderofbytes=0x410x1C0xF50xC3
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Thebit‐orderinabyteisalways:
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[MSB…LSB]Æ[bit7…bit0]

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TwostopbitsareneededfordevicesproducedearlierthanJanuary1
st
2008inordertoallowcorrectframe‐
timing.Onestopbitisalways
possibleinreceive‐onlymode.FordevicesproducedsinceJanuary1
st
2008one
stopbitcanbeusedinanymode.