Schneider Optics Modicon Quantum Ethernet manual Modbus Application Protocol PDU, Is defined below

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Quantum Ethernet TCP/IP Modbus Application Protocol

C.1.1 Modbus Application Protocol PDU

The Modbus Application Protocol PDU, mbap_pdu, is received at TCP port number

502.The current maximum size of the mbap_pdu for this class of services is 256 bytes. The structure and content of the mbap_pdu is defined to be:

mbap_pdu ::={ inv_id[2], proto_id[2], len[2],dst_idx[1], data=mb_pdu }

The header is seven bytes long and includes the following fields:

inv_id

[2 bytes] invocation id used for transaction pairing

proto_id

[2 bytes] used for intra-system multiplexing, default is 0 for

 

Modbus services

len

[2 bytes] the len field is a byte count of the remaining fields and

 

includes the dst_id and data fields

The remainder of the pdu includes two fields:

dst_idx

[1 byte] destination index is used for intra-system routing of

 

packets (currently not implemented)

data

[n bytes] this is the service portion of the Modbus pdu, mb_pdu

 

and is defined below

The service portion of the Modbus Application Protocol, called mb_pdu, contains two fields:

mb_pdu ::={ func_code[1], data[n] }

func_code[1 byte] Modbus function code

data

[n bytes] this field is function code dependent and usually

 

contains information such as variable references, variable

 

counts and data offsets

The size and content of the data field are dependent on the value of the function code.

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Contents Modicon Quantum Ethernet USE 115 00 VersionTraining USE 115 00 Vesion Modicon Quantum EthernetOctober Document Set Preface USE 115 00 Version Contents Using the Network Options Ethernet Tester Chapter MaintenanceMstr Instruction Retrieving Data via the World Wide WebAppendix a Specifications Appendix D Suppliers Glossary IndexContents Viii About This Book Document Scope Validity Note Related DocumentationIntroduction Ethernet Web Embedded Server Modules Benefits of Quantum DesignModels for Fiber Optic and Twisted Pair Cable Systems Type of Cable Network Part NumberFront Panel Components Removable Door140 NOE 251 Color Indication When On LED DisplayAddress Labels EthernetAddress Label Internet Protocol IP Network Address LabelExample Calculating the Derived IP Network Address Locate the global address label onFront panel of the module 0 B 7 2 aFiber Optic Connectors Twisted Pair ConnectorTransmit Data Network Options Ethernet Tester Utility DisketteErrlog Ethernet and Your Application Meeting the Demands of Your ApplicationCompatibility Guidelines for Designing Your NetworkDelays Using SwitchesSegregating TrafficInstalling and Configuring Module Before You Begin Verifying the Default ConfigurationVerifying that the Network Has Been Constructed Properly Improper Network TopologiesAre You Really Ready to Install? Check Installing the ModuleMounting the Module on the Backplane Connecting the Cable With connectors 990 XCA 656Twisted Pair Snap into placeAttaching the Cable Changing the Default Configuration Configuring the Module with ModsoftSelecting the Ethernet Framing Type Assigning a Slot NumberResetting the Module Assigning the Default Gateway Address and Subnet MaskAssigning the IP Network Address Configuring More Than One Ethernet Module Configuring the Module with Concept Parameter Dialog for an Ethernet Web Embedded Server ModuleMstr Description Mstr Instruction IntroductionMstr Operation Code TCP/IP Ethernet Support Characteristics SizeCompatibility Opcode BF hexContent RepresentationInputs OutputsMstr Function Error Codes Error CodesMiddle Node Bottom NodeHex Error Code Meaning Ss Hex value MeaningHex Error Code Meaning 5016 An argument is valid Read and Write Mstr Operations Control BlockUtilization Information as described in the following tableGet Local Statistics Mstr Operation Statistics information as described in the following tableClear Local Statistics Mstr Operation Get Remote Statistics Mstr OperationClear Remote Statistics Mstr Operation Peer Cop Health Mstr Operation Peer CopCommunications Health StatusType Word Status IndexRead CTE Config Extension Table Mstr Operation Reset Option Module Mstr OperationModule information as described in the following table Parameter Register Content CTE DisplayImplementation Registers. The registers display the following CTE dataWrite CTE Config Extension Table Mstr Operation 13 TCP/IP Ethernet Statistics Word MeaningRetrieving Data via the World Wide Web Introduction Accessing the Web Utility Home Web Utility HomeWeb Utility for Quantum Quantum Web UtilityRetrieving Data via the World Wide Web Using the Network Options Ethernet Tester Introduction Installing the Network Options Ethernet Tester Establishing a Connection with an Ethernet ModuleMain Menu Getting and Clearing Statistics Get Statistics BoxMAC Address Sample StatisticsUsing the Network Options Ethernet Tester Reading and Writing Registers Read Register BoxWrite Register Box Maintenance Responding to Errors Detecting ErrorsActive LED Ready LEDLink LED Fault LEDKernel LED Collision LED LED Display for Improperly Connected Twisted Pair CableReading and Clearing the Error Log Application LEDDefault is Example Errlog 49 EBX, EBP, ESI, EDI, ESP, EFLAGS, EIPExample Sample Error Log To restart the controller, type YHot Swapping An Ethernet Module Downloading a New Software Image From the Device to Download menu, select Local HeadUSE 115 00 Version Specifications Power Dissipation Bus Current Required Operating ConditionsCommunication Ports Storage ConditionsSpecifications Ethernet Developers Guide Introduction ReferencesOverview Development EnvironmentClass Descriptions CSampledoc Class CSampleView Class Accessing TCP/IPEvent Description Application Message Format Network Event Member FunctionTimers Transaction ProcessingTransmit State Machine Exists the loop Receive State Machine Ethernet Developers Guide Displaying on the Screen Quantum Ethernet TCP/IP Modbus Application Protocol Modbus Application Protocol PDU Includes the dstid and data fieldsIs defined below Counts and data offsetsModbus Application Protocol Service Classes Modbus Application Protocol PDU Analysis Quantum Ethernet TCP/IP Modbus Application Protocol Broadcast/Multicast TCP/IP Specific IssuesTCP Port Number Reference Documents Quantum Ethernet TCP/IP Modbus Application Protocol Suppliers Suppliers Glossary AddressBps BridgeDefault gateway FieldFrame Framing typesHub InternetIP Address IO MapOSI model PacketPort ProtocolSwitch SocketStack SubnetGlossary Index Index Mstr Network Options Ethernet Tester World Wide Web server