Teledyne 9060Z APPENDIX4,MODBUS

Model9060ZManual
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APPENDIX4,MODBUS™
TheTeledyneAnalyticalInstruments9060ZtransmitterhastheabilitytoworkasaModbusslavenode
onserialRS‐232or3‐wireRS‐485viaRTUmodetransmissions.Byaccessinginformationstoredinthe
inputandholdingregistersitispossibletoaccessruntimevariables,alarmconditionsandmodifythe
deviceconfiguration.
TheimplementationoftheModbusprotocolislimitedtothespecificcommandsetrelevantto
readingandwritingregistervariables.Attemptingtosendunrecognisedcommandswillresultin
appropriateerrorresponses
MODBUS™FunctionsSupported:‐
0x03:ReadHoldingRegisters
0x04:ReadInputRegisters
0x06:WriteSingleHoldingRegister
0x08:(returnquerydata–forloopbacktesting)
0x10:WriteMultipleHoldingRegisters
0x16:MaskWriteHoldingRegister
0x17:Read/WriteMultipleHoldingRegisters
0x2B:EncapsulatedInterface(readdevice
information)
0x41:SpecialInstructionFunction
SerialConfiguration
TheserialconfigurationfortheslavedeviceisaccessedintheCommissioningmenuofthe
transmitter.Defaultsettingsarehighlightedinbold.
BaudRate 9600,19200,38400,57600
Parity Even,Odd,None
StopBits 1
Interface RS‐485,RS‐232
Allholdingregisteraddressescontainasingle16bitvalue,howeversomevariablesspanmultiple
holdingregisterstoyieldasingle32bitvariable.
Whenreadingregistervaluesbeawarethatthebyteorderofdatawithinregistersmaydifferfrom
thatofthetargetsystem.
ModbusProtocol
Themodbusoverseriallineprotocoldefinesamessagingsystemformaster/slavecommunications.
Onlyonemasterdevicemaybeconnectedtoanynetworkwithoneorseveralslavenodes.
Inunicastmode,themasterinitiatescommunicationwithaspecificslavenodebysendingarequest
message.Theslaveprocessestherequestandreturnsareplymessagecontainingtherequested
informationoraconfirmationthattherequestwasfulfilled.
ModbusrequestsaretransmittedasaformedrequestframewithaCRCfordataintegritychecking.
Theframeforeachrequestandreplytypewillvarysomewhat,butwillalwayshavethebasic
structuredescribedbelow:
1byte 1byte upto255bytes 2bytes
slaveaddress functioncode data checksum
InternalRepresentationofDates&AlarmStatus
Thetransmitterstoresalldatesasanunsigned32bitcountofsecondselapsedsince1‐Jan2004.