Overview, Socket Service Functions | Omron CJ1W-ETN21 specification

Overview

Section 6-3

3.Data A and Data B are sent consecutively.

4.When the receiving user program sends a request to receive 1,984 bytes of data, Data A and Data B are linked to restore the original data, which is passed to the user program.

Sending User Program		Ethernet Unit				Receiving Node		Receiving User Program
1. Send request
1,984bytes		1,472 bytes
Source data			Data A					4. First receive request
Source data			Data A


									1,984 bytes
			Data B			Data A	Data B
			512 bytes

2.3.

As shown above, the UDP protocol handles data communications as datagrams, so that the send data is restored to the original data before being passed to the user program. Consequently, if the data length in the receive request is set to the length of the send data, the entire data can be received using a single receive data request. However, if the data length in the receive data request is set smaller than the actual length of the data, all received data exceeding the set data length will be discarded.

6-3 Overview

6-3-1 Socket Service Functions

The Ethernet Unit’s socket services are used to exchange data between the PLC and general-purpose applications that do not support FINS message communications.The socket services can be used by CS/CJ-series PLCs through the user program by manipulating dedicated control bits (called Socket Service Request Switches) or by executing the CMND(490) instruction.

Intranet

General-purpose application (not FINS communications);

The host computer uses system calls to call sockets provided in a C language interface library to allow TCP and UDP protocols to be used directly to access PLC data.

Ethernet

User-set data

Ethernet Unit

The program in the CPU Unit sends requests to the Ethernet Unit to open/close sockets or send/receive data. This is achieved by manipulating dedicated control bits or executing CMND(490), and allows the CPU Unit to exchange data with the host computer by using UDP or TCP protocols directly.

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Omron CJ1W-ETN21 operation manual Overview, Socket Service Functions

Contents

Ethernet Units Construction of Applications Revised November  Omron Omron Product ReferencesPage Table of Contents FTP Server Index 207 Revision History 215 Table of Contents Section Contents Information on setting communications using CX-ProgrammerInformation on how to manage and use IP addresses Commands Relevant Manuals Manual Model Name Contents Number Xiii Xiv Read and Understand this Manual Application Considerations Disclaimers Xviii Notation of Unit Versions on Products Unit VersionsConfirming Unit Versions with Support Software Lowing table Unit Version Notation Precautions Safety Precautions General PrecautionsIntended Audience Safety Precautions Application Precautions Operating Environment Precautions Application Precautions EMC Directives Conformance to EC DirectivesApplicable Directives Concepts Section Acquired for the Ethernet Unit Ethernet Unit Communications ServicesService Main functions Counterpart device Reference Functions Listed by Purpose Section Communications Protocol used Situation when used ReferenceUnit setting tag Table of Protocols Contents Default Common Protocol SettingsSmtp 2 POP 3 DNS Section Section Mail Send Function Description Mail Send Function OverviewIntroduction Advantages Comparison with the Earlier Mail Send Function Mail Send Function DetailsMail Send Functions Compatibility with Earlier Models Contents of E-mail Body Trigger condition Text entered as subject Following header information is included Optional Information Words value has changed Channel data has changed from XX toEthernet Unit Information Ethernet Unit information is always included in the e-mail Memory Data 6,000 Words Max Error Log Information Status InformationExtension Content Attached File Details File Data 1 MB Max Summary of E-mail Body Information and Attached FilesData sent Body/Attached file Mail body Function Specifications Mail Send Function SpecificationsSpecifications Classification Trigger type Using the Mail Send FunctionProcedure Details of the Available Mail Triggers Unit Setup Settings Required for the Mail Send FunctionTransferring the settings data Setting Setting requirement Reference Using the Mail Send Function Mail Address Set up to 2 destination mail addressesSend Mail Data Sent in an Attached File Send Mail Condition SettingsMail Address Specification Required Data Sent by Mail When Required Data Sent in E-mail Body Attached File Name Send Mail Trigger Type Setting Required Send Mail Status Mail Send Function StatusSend Mail Status Mail Send Switch Bit 03 of n Mail Send Switch, Accessing Memory/Sending Mail FlagBit numbers Status TXT Format Accessing Memory/Sending Mail Flag Bit 01 of n+17Memory Data Formats IOM Format CSV Format Attached File Transfer Times Access Times for CS1-H and CJ1-H CPU Units Mail Send Function ErrorsIdentifying and Correcting Mail Send Function Errors Access Times for CS1 and CJ1 CPU Units Probable cause Correction Troubleshooting Mail Send Errors with LED IndicatorsError Log Error Codes for the Mail Send Function Error Meaning Detailed error code Correction Example Application Make the Unit Setup Settings from the CX-ProgrammerInitial Settings Example Initial Server Settings Send Condition Setting Destination Mail Address Setup Send when there is a Change in the CPU Units Status Transfer the CPU Bus Unit Setup SettingsAutomatic Transmission when Send Condition is Satisfied Example Send e-mail when W300 bit 00 goes from OFF to on Receive Mail Function Description Configuration of the MailMail Receive Function Overview Advantages Attached File Data Table of Remote Mail CommandsCommand Parameters Command Execution Results Specification Mail Receive Function SpecificationsReceived E-mail Response E-mail Using the Mail Receive Function Tion Settings Required for the Mail Receive Function Receive Mail Tab Posting Mail Address Protection Setting Receive Command Setting Receive Attached File Setting Response Format Remote Mail Command DetailsCommand Format Format Mounted in the CPU Unit Command FormatFileWrite File Write Function FileRead File Read Card mounted in the CPU Unit FileDelete File Delete EM file memory or a Memory Card mounted in the CPU Unit FileList File List ReadResponse Format Details Command Format Details UMBackup User Memory BackupMemory or a Memory Card mounted in the CPU Unit Or a Memory Card mounted in the CPU Unit PARAMBackup Parameter Area Backup Units I/O memory. The data is written in word units IOMWrite I/O Memory Write Subject Body Units IOMRead I/O Memory Read ReIOMRead Changes the CPU Units operating mode ChangeMode Operating Mode Change Bus Unit or Special I/O Unit ErrorLogRead Error Log Read ErrorLogClear Error Log Clear MailLogRead Mail Log Read Since power was turned on or the mail log was cleared Net Unit MailLogClear Mail Log Clear Test Mail Test Response List FinsSend Fins Command SendResponse Response Status Description Code IOM Format Accessing Memory/Receiving Mail FlagAccessing Memory/ Receiving Mail Flag Bit 02 of n+17 Mail Receive Function Status CSV Format TXT Format Access Times for CS1-H CJ1-H CPU Units Access Times for CS1 CJ1 CPU Units Identifying and Correcting Mail Receive Function Errors Mail Receive Function ErrorsTroubleshooting Mail Receive Errors with LED Indicators Hex 1st byte 2nd byte Error code Meaning Detailed error code Correction Initial Settings for the Mail Receive Function DNS Server IP Address Setting DNS Tab, When RequiredItem name Example Reading Data from a CPU Unit Data Area Send Remote Mail CommandsBacking Up the CPU Units User Program Memory Card FTP Server Overview Specifications FTP Server Function Details Connecting to the FTP ServerFile Types FTP File Transfer Mode Using the FTP Server Function Setting Details Default value List of Settings Required for the FTP Server FunctionSetup Tab CX-Programmer Settings Setting conditions Tab Confidential FTP Server Application Example Open Using FTP CommandsTable of Commands Using the Commands Dir UserRename Cdup MkdirRmdir Pwd Put TypeGet Mget Bye DeleteMdelete Close Error Messages Error Messages and FTP StatusMessage Meaning FTP Status Flag FTP IndicatorFTP indicator Meaning Checking FTP Status Directories Using File MemoryFile Memory File Names File Names Handled by CPU Unit File type File name Extension Contents DescriptionUnit Data format Use of CRs and CR position Initializing File Memory4 I/O Memory Data Format Memory Initialization method Section 9ABC File system Memory Card EM File Memory FTP File Transfer TimeCS1 CPU Units/CJ1 CPU Units CS1-H CPU Units/CJ1-H CPU Units Unix Application Example Enter the login name Write the file PLAN.IOM to the Memory Card Change to the Memcard directoryChange data type to binary Transfer the file RESULT.IOM to the workstation Section Automatic Clock Adjustment Function CPU Unit Conditions Overview Using the Automatic Clock Adjustment Function Settings Setting conditions Reference Settings Required for Automatic Clock Adjustment Function Auto Adjust Time Automatic Clock Adjustment Switch Bit 04 of n Automatic Clock Adjustment SwitchAutomatic Clock Adjustment Error Processing Automatic Clock Adjustment Sntp Errors Automatic Clock Adjustment Error Processing CPU Unit error Socket Services Page Socket Port Numbers Using Sockets with the Ethernet UnitOverview of Socket Communications from Ethernet Units What are Sockets? TCP Communications Protocol OverviewDifferences between TCP and UDP Opening TCP Sockets Passive Open and Active Open TCP Communications Procedure Fragmentation of Send Data Socket Service Functions Protocol Socket Service Request CMND490 Using Socket Services with Socket Service Request Switches Protocol Socket service request Using Socket Services with CMND490Specific Socket Service Functions Command code Name Executing CMND490 Socket Service Function GuideDifferences with Previous Models Manipulating Dedicated Control Bits Manipulating Dedicated Control Bits Using Socket Service FunctionsSettings Required for Socket Service Function CX-Programmer Setting Setting requirements Unit Setup Tab Details Default value Setup 109 CIO Area Allocations Socket Service StatusUDP/TCP Socket Status Ethernet Unit to CPU Unit DM Area Allocations Bit Switch Status Manipulated Unit operation Number Status Meaning Application ProcedureProcedure TCP Connection Status Ethernet Unit to CPU Unit Precautions Socket Services and Socket Status Program Flow Error Evaluation Socket Service Parameters TCP Socket Services Parameter SettingsUse of the parameters by the socket service UDP Socket Services Local UDP/TCP Port No ParametersSocket Option UDP/TCP Socket No Number of Bytes to Send/Receive Following specifications can be usedRemote UDP/TCP Port No Time Out Time Following diagram Socket Service Request Switches Response Meaning Code Response CodesUDP Socket Open Request UDP Socket Receive Request UDP Socket Close Request UDP Socket Send Request TCP Socket Active Open Request TCP Socket Passive Open Request Drinuse TCP Socket Receive Request TCP Socket Send Request Processes Timing ChartsTCP Socket Close Request Closing during Other Force-close Switch Close Request Switch Basic Operations System Configuration8 TCP/IP Communications Programming Example Data Flow DM Area Program Memory MapCIO Area TCP Passive Open Programming Example 130 9 UDP/IP Communications Programming Example Programming example uses the following system configuration CIO 000000 is turned on to request opening a UDP socket from Tion on errors 133 134 135 Using Socket Service Using Socket Services with CMND490 137 Results Storage Area Basic Fins Command FormatCommand Code Socket Number Response Codes in the Results Storage Areas Response Codes in the Command ResponseCommunications Timing Chart Socket Service Timing Chart 140 Close Request during Receive Request System Configuration Basic Operations Data Flow Are structured Program Memory Maps 144 145 146 147 148 149 150 151 152 153 154 TCP Socket Service Precautions in Using Socket ServicesUDP and TCP Socket Services UDP Socket Service Precautions in Using Socket Service Request Switches TCP Socket Services Using CMND490 CS/CJ CPU Units Maximum Transmission Delays Ignoring other Network DelaysCS-H/CJ-H CPU Units Calculation Using Fins Communications to Create Host Applications Communications On an Ethernet Network Overview of Fins Communications Fins Communications Service Specifications for Ethernet Using the FINS/UDP and FINS/TCP Methods Fins Header Information Fins Command Frame FormatFins Frames Fins Response Frame Format FINS/UDP Method FINS/UDP Features FINS/UDP FINS/UDP Frame Format UDP Port Numbers for Procedure for Using Designating Remote Addresses Sending Commands from a Host ComputerCommunications Parameters Used by Host Computer Operation Overview By sending a Fins command Memory Area READ, command codeMand, the command will be resent FINS/UDP Sample Program 15 * FINS/UDP Communications Sample Program Sample Program 169 170 FINS/TCP Method FINS/TCP Features TCP Port Number for FINS/TCP Frame FormatFINS/TCP Connection Numbers FINS/TCP Connection Status Word n+23 CommunicationsAge them in an internal table Automatic Allocation Fins Node Addresses Automatic Allocation Procedure 175 FINS/TCP Tab Setup Tab FINS/TCP Headers FINS/TCP Mode SpecificationsFins Node Address Data Send Client to Server Command Fins Node Address Data Send Server to Client Command Following table shows the list of error codes Fins Frame Send CommandError code Details Hexadecimal Command Fins Frame Send Error Notification Command Normal Operation Connection Sequence ACK FIN Error Connection Sequence 182 183 Host computer Remote node From onwards, the connection is established again FINS/TCP Sample Program 186 187 188 189 190 191 Receive Processing Command CPU Bus Unit Service Cycle Maximum Transmission Delays Writing/Reading to CPU UnitWrite Command Delay Time Transmission Delay Response Read Command Delay TimeTransmission Processing 704 ms 194 Parameter Value Description Ethernet Network Parameters Appendix a Appendix B Buffer Configuration Network Memory Status Meaning TCP Status Transitions Appendix C Space Ascii Characters Appendix D Replacing an Ethernet Unit MaintenanceSettings after Replacing an Ethernet Unit Settings After Replacing a CPU Appendix E Items InspectionsTools Required for Inspection Appendix F Numerics Index 209 210 211 212 213 214 Revision History Revision code Date Revised content Revision History Regional Headquarters Omron Corporation Control Devices Division H.Q Authorized Distributor