Mitsubishi Electronics Digital Garage Door Opener Fx3U Users Manual ENET L USER'S

FX3U to the manual c77e852e-c715-41af-bd3f-5fd5117ce0f2

2015-02-09

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FX3U-ENET-L
USER'S MANUAL

SAFETY PRECAUTIONS
(Read these precautions before use.)
Before installation, operation, maintenance or inspection of this product, thoroughly read through and
understand this manual and all of the associated manuals. Also, take care to handle the module properly and
safely.
This manual classifies the safety precautions into two categories: "DANGER" and "CAUTION."

DANGER

Indicates that incorrect handling may cause hazardous conditions,
resulting in death or severe injury.

CAUTION

Indicates that incorrect handling may cause hazardous conditions,
resulting in medium or slight personal injury or physical damage.

Depending on the circumstances, procedures indicated by CAUTION may also cause severe injury.
It is important to follow all precautions for personal safety.
Store this manual in a safe place so that it can be taken out and read whenever necessary. Always
forward it to the end user.

[Design Precautions]
DANGER
To prevent malfunctions of the PLC system that may be caused by illegal e-mail, take proper
countermeasures (such as virus detection) so that illegal e-mail is not received by the mail
server of this module.
If it is necessary to ensure the security of the PLC system against unauthorized access from
external devices via the Internet, appropriate measures must be incorporated by the user.
When controlling the PLC (modifying data) while it is in operation by connecting computer
peripheral devices to the main unit or connecting personal computers to the extension device,
make sure to have an interlock circuit outside of the PLC to ensure safe system operation.
Do not write any data in the "system area" of the buffer memory of the extension device. When
writing a value to the buffer memory including "System Area," pay close attention not to change
the system bit. If data is written to the "system area" or the "use prohibited" signal is output,
there is a risk that the PLC system may malfunction.
When the program examples introduced in this manual are applied to the actual system,
examine the safety of the control in the target system.

A-1

A-1

[Design Precautions]
CAUTION
When the status control (remote RUN/STOP) of the PLC is performed from the external device,
select the "Always wait for OPEN" parameter set by an user in advance. (Select with the initial
timing setting (BFM#24 b8) in the operational setting.) When "Do not wait for OPEN" is selected,
the communication line at remote STOP is closed. The communication line cannot be reopened
on the PLC side after that, and the remote RUN from the external device cannot start.

[Installation Precautions]
CAUTION
Use the product within the generic environment specifications described in chapter 3 of this
manual.
Never use the product in areas with excessive dust, oily smoke, conductive dusts, corrosive gas
(salt air, Cl2, H2S, SO2 or NO2), flammable gas, vibration or impacts, or exposed to high
temperature, condensation, or rain and wind.
If the product is used in such conditions, electric shock, fire, malfunctions, deterioration or
damage may occur.
When drilling screw holes or wiring, make sure cutting or wire debris does not enter the
ventilation slits.
Failure to do so may cause fire, equipment failures or malfunctions.
Be sure to remove the dust proof sheet from the PLC's ventilation port when installation work is
completed. Failure to do so may cause fire, equipment failures or malfunctions.
Connect the extension cables securely to their designated connectors.
Unsecured connection may cause malfunctions.

A-2

A-2

[Wiring Instructions]
DANGER
Before mounting or wiring the module, make sure to shut off all of the external power supply.
Failure to do so may cause electric shocks or damage the module.
When turning on the power and operating after mounting or wiring the module, make sure to
install the accessory terminal covers to the product.
Otherwise, it may cause electric shocks.

CAUTION
Make sure to place the communication cables and the power cables in a duct or fasten them
using a clamp.
If the cables are not placed in a duct or fastened with a clamp, their positions can be unstable,
moved and pulled inadvertently. This may damage the module and the cables, or cause the
module malfunction due to unsecured cable connections.
When disconnecting the communication cables and the power cables, do not pull the cables.
When disconnecting a cable with a connector, hold the connector to the module by hand and
pull it out to remove the cable.
When disconnecting a cable connected to a terminal block, loosen the screws on the terminal
block before removing the cable.
If a cable is pulled while being connected, it may cause the module malfunction or damage the
module and the cable.
Do not bundle the control line and the communication cables together with or lay it close to the
main circuit or power line. As a guideline, lay the control line and the communication cables at
least 100mm (3.94") or more away from the main circuit or power line.
Noise may cause malfunctions.
Before connecting twisted pair cables, the ground pin brush grounded via a resistor enables
discharging static electricity on the cables effectively. This can prevent the electrostatic
discharge to the product.

A-3

A-3

[Setup and Maintenance Precautions]
DANGER
Do not touch any terminal while the PLC's power is on.
Doing so may cause electric shock or malfunctions.
Before cleaning or retightening terminal screws and module mounting screws, externally cut off
all phases of the power supply.
Failure to do so may cause electric shock, fire, malfunctions and product damage.
Before modifying or disrupting the program, forcible output, RUN and STOP while they are in
operation, carefully read through this manual and the associated manuals and ensure the safety
of the operation.
An operation error may damage the machinery or cause accidents.

CAUTION
Do not disassemble or modify the PLC.
Doing so may cause fire, equipment failures, or malfunctions.
For repair, contact your local Mitsubishi Electric distributor.
Cut off all phases of the power supply externally before installation or wiring work in order to
avoid damage to the product or electric shock.

[Precautions When Disposing of This Product]
CAUTION
Dispose of this product as an industrial waste.

[Transportation Precautions]
CAUTION
The PLC is a precision instrument. During transportation, avoid impacts larger than those
specified in the general specifications of the PLC main unit manual.
Failure to do so may cause failures in the PLC.
After transportation, verify the operations of the PLC.

Other company and product names herein are either trademarks or registered trademarks of their respective owners.
Microsoft , Windows 2000, Outlook , Visual C++ and Visual Basic are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.
This manual confers no industrial property rights or any rights of any other kind, nor does it confer any patent
licenses. Mitsubishi Electric Corporation cannot be held responsible for any problems involving industrial property
rights which may occur as a result of using the contents noted in this manual.

A-4

A-4

CONTENTS
SAFETY PRECAUTIONS .....................................................................................................................A- 1
CONTENTS ..........................................................................................................................................A- 5
About Manuals ......................................................................................................................................A- 9
Associated Manuals..............................................................................................................................A- 9
Applicable Standard..............................................................................................................................A-10
The Manual's Usage and Structure.......................................................................................................A-12
About the Generic Terms and Abbreviations ........................................................................................A-14
1 OVERVIEW

1- 1 to 1- 9

1.1 Overview of the Ethernet Module................................................................................................... 1- 1
1.2 Features of the Ethernet Module ................................................................................................... 1- 3
1.3 Software Configuration .................................................................................................................. 1- 7
2 SYSTEM CONFIGURATIONS

2- 1 to 2- 3

2.1 Applicable Systems........................................................................................................................ 2- 1
2.2 Devices Required for Network Configuration ................................................................................. 2- 2
3 SPECIFICATIONS

3- 1 to 3-25

3.1 Performance Specifications ........................................................................................................... 33.2 Data Codes for Communication ..................................................................................................... 33.3 Relationship between the External Devices and Additional Functions for Each Communication
Function ......................................................................................................................................... 33.4 Ethernet Module Function List ....................................................................................................... 33.5 List of Setting Items for Ethernet Modules ..................................................................................... 33.6 List of Applications and Assignments of the Buffer Memory .......................................................... 34 SETTINGS AND PROCEDURES PRIOR TO OPERATION

1
3
5
6
7
8

4- 1 to 4-17

4.1 Loading and Installation ................................................................................................................. 4- 1
4.1.1 Handling precautions ............................................................................................................... 4- 1
4.1.2 Installation environment ........................................................................................................... 4- 2
4.2 Settings and Procedures Prior to Starting the Operation ............................................................... 4- 3
4.3 Components of the Ethernet Module ............................................................................................. 4- 5
4.4 Connecting to the Network............................................................................................................. 4- 7
4.4.1 Connecting to the 10BASE-T/100BASE-TX network............................................................... 4- 8
4.5 Ethernet Module Setting ................................................................................................................ 4- 9
4.6 Operational Settings ...................................................................................................................... 4-10
4.7 Self-Diagnostic Tests ..................................................................................................................... 4-14
4.7.1 Self loopback test..................................................................................................................... 4-14
4.7.2 Hardware test (H/W Test) ........................................................................................................ 4-15
4.8 Maintenance and Inspection .......................................................................................................... 4-16
4.8.1 Maintenance and inspection .................................................................................................... 4-16
4.8.2 Installing and uninstalling the module ...................................................................................... 4-17

A-5

A-5

5 COMMUNICATION PROCEDURE

5- 1 to 5-46

5.1 Overview of the Communication Procedure .................................................................................. 5- 1
5.2 Initial Processing............................................................................................................................ 5- 3
5.2.1 Initial processing ...................................................................................................................... 5- 3
5.2.2 Initial settings ........................................................................................................................... 5- 4
5.2.3 Re-initialization......................................................................................................................... 5-10
5.3 Router Relay Parameter ................................................................................................................ 5-13
5.4 Confirming the Completion of the Initial Processing ...................................................................... 5-15
5.4.1 PING command (Personal computer
Ethernet module) .................................................... 5-16
5.4.2 Loop back test (Communication using MC protocol) ............................................................... 5-17
5.5 Open Settings ................................................................................................................................ 5-18
5.5.1 Fixed buffer connection (connection No. 1 and connection No. 2) .......................................... 5-18
5.5.2 MELSOFT/MC protocol connections (connection No. 3 and connection No. 4) ...................... 5-24
5.6 Open Processing/Close Processing of the Connection ................................................................. 5-25
5.6.1 Active open processing/close processing ................................................................................ 5-27
5.6.2 Passive open processing/close processing ............................................................................. 5-33
5.6.3 UDP/IP open processing/close processing.............................................................................. 5-40
5.7 Pairing Open .................................................................................................................................. 5-43
5.7.1 Pairing open............................................................................................................................. 5-43
5.7.2 Example of pairing open settings............................................................................................. 5-44
5.8 Hub Connection Status Monitor Function ...................................................................................... 5-46
6 FIXED BUFFER COMMUNICATION
(WITH THE PROCEDURE EXIST CONTROL METHOD)

6- 1 to 6-18

6.1 Control Method .............................................................................................................................. 6- 1
6.2 Sending Control Method ................................................................................................................ 6- 3
6.3 Receiving Control Method.............................................................................................................. 6- 6
6.3.1 Receive processing with the main program ............................................................................. 6- 6
6.4 Data Format ................................................................................................................................... 6- 8
6.4.1 Header ..................................................................................................................................... 6- 8
6.4.2 Application data ....................................................................................................................... 6- 9
6.5 Programming ................................................................................................................................. 6-13
6.5.1 Precautions when creating programs ...................................................................................... 6-13
6.5.2 Fixed buffer communication program example (with the procedure exist control method)...... 6-14
7 FIXED BUFFER COMMUNICATION
(WITH THE NO PROCEDURE CONTROL METHOD)

7- 1 to 7-14

7.1 Control Method .............................................................................................................................. 7- 1
7.2 Sending Control Method ................................................................................................................ 7- 4
7.3 Receiving Control Method.............................................................................................................. 7- 6
7.3.1 Receive processing with the main program ............................................................................. 7- 6
7.4 Data Format ................................................................................................................................... 7- 8
7.5 Programming ................................................................................................................................. 7- 9
7.5.1 Precautions when creating programs ...................................................................................... 7- 9
7.5.2 Fixed buffer communication program example (with the no procedure control method) ......... 7-10

A-6

A-6

8 COMMUNICATION USING MC PROTOCOL

8- 1 to 8- 5

8.1 Data Communication Function....................................................................................................... 88.1.1 Accessing the PLC using MC protocol..................................................................................... 88.1.2 How to Read the Control Procedures of the MC Protocol ....................................................... 88.1.3 Access Timing on the PLC Side .............................................................................................. 88.1.4 PLC setting for performing data communication...................................................................... 88.1.5 Precautions on Data Communication ...................................................................................... 89 WHEN COMMUNICATING DATA USING THE MC PROTOCOL

1
1
2
3
4
4

9- 1 to 9-40

9.1 Message Formats and Control Procedures ................................................................................... 9- 1
9.1.1 How to read the command reference section .......................................................................... 9- 1
9.1.2 Message format and control procedure ................................................................................... 9- 3
9.1.3 Contents of data designation items.......................................................................................... 9- 7
9.1.4 Character area transmission data............................................................................................ 9-11
9.2 List of Commands and Functions for The MC protocol.................................................................. 9-15
9.3 Device Memory Read/Write ........................................................................................................... 9-16
9.3.1 Commands and device range .................................................................................................. 9-16
9.3.2 Batch read in bit units (command: 00) ..................................................................................... 9-19
9.3.3 Batch write in bit units (command: 02)..................................................................................... 9-21
9.3.4 Test in bit units (random write) (command: 04) ....................................................................... 9-23
9.3.5 Batch read in word units (command: 01) ................................................................................. 9-25
9.3.6 Batch write in word units (command: 03)................................................................................. 9-29
9.3.7 Test in word units (random write) (command: 05) ................................................................... 9-33
9.4 Remote RUN/STOP, PLC model name code read ........................................................................ 9-35
9.4.1 Commands and control contents ............................................................................................. 9-35
9.4.2 Remote RUN (command: 13) / Remote STOP(Command: 14) ............................................... 9-36
9.4.3 PLC model name read (command: 15).................................................................................... 9-38
9.5 Loopback Test ............................................................................................................................... 9-39
9.5.1 Loopback test (command: 16) ................................................................................................. 9-39
10 USING THE E-MAIL FUNCTION

10- 1 to 10-19

10.1 E-mail Function .......................................................................................................................... 10- 1
10.1.1 E-mail send by the PLC ....................................................................................................... 10- 1
10.2 Configuration and Environment of the Applicable System ......................................................... 10- 3
10.3 Precautions for Using the E-mail Function................................................................................. 10- 4
10.4 E-mail Specifications.................................................................................................................. 10- 5
10.5 Processing Procedure of the E-mail Function............................................................................ 10- 6
10.6 E-mail Settings........................................................................................................................... 10- 7
10.7 Sending E-mail (Attached Files) by the PLC.............................................................................. 10-10
10.7.1 When sending data as an attached file................................................................................ 10-10
10.7.2 Contents of the attached files .............................................................................................. 10-16
10.8 Sending E-mail (Main Text) by the PLC..................................................................................... 10-17
10.8.1 When sending data as main text of e-mail........................................................................... 10-17

A-7

A-7

11 TROUBLESHOOTING

11- 1 to 11-42

11.1 How to Check Errors Using LED Displays ................................................................................. 11- 2
11.1.1 Checking error display ......................................................................................................... 11- 2
11.1.2 How to turn off COM.ERR LED and to read/clear error information .................................... 11- 4
11.2 How to Check an Error Through FX Configurator-EN-L ............................................................ 11- 6
11.2.1 Buffer memory that can be monitored with the FX Configurator-EN-L diagnostic function.. 11- 7
11.2.2 Ethernet diagnostics ............................................................................................................ 11- 9
11.3 Checking the error information by the buffer memory batch monitoring function ...................... 11-10
11.4 Error Code List........................................................................................................................... 11-11
11.4.1 Type of error incident ........................................................................................................... 11-11
11.4.2 End codes (Complete codes) returned to an external device during data communication.. 11-17
11.4.3 Abnormal codes returned during communication using MC protocol .................................. 11-18
11.4.4 Error codes stored in the buffer memory ............................................................................. 11-19
11.5 Troubleshooting Flowchart......................................................................................................... 11-32
11.5.1 Sending errors during fixed buffer communication
(common to procedure exist and no procedure).................................................................. 11-35
11.5.2 Receiving errors during fixed buffer communication
(common to procedure exist and no procedure).................................................................. 11-37
11.5.3 Errors in communication using MC protocol ........................................................................ 11-40
11.5.4 Sending errors during e-mail communication ...................................................................... 11-42
APPENDIX

App- 1 to App-26

Appendix 1 Processing Time ...........................................................................................................App- 1
Appendix 2 ASCII Code List ............................................................................................................App- 4
Appendix 3 References....................................................................................................................App- 4
Appendix 4 Program Examples .......................................................................................................App- 5
Appendix 4.1 Program example for communication using MC protocol -1 ...................................App- 6
Appendix 4.2 Program example for communication using MC protocol -2 ...................................App-14
Appendix 5 Differences between the Ethernet and the IEEE802.3 .................................................App-19
Appendix 6 ICMP Protocol Supported by the Ethernet Module .......................................................App-19
Appendix 7 Setting Value Recording Sheets ...................................................................................App-20
Appendix 8 Versioin Information ......................................................................................................App-25

A-8

A-8

About Manuals
This manual explains the mounting of FX3U-ENET-L, the specifications, broadcast
functions and communication methods.
For the instructions and programs of the sequence as well as the parameter settings
by FX Configurator-EN-L, also refer to the following manuals.
Associated Manuals
Manual name

Manual No.
JY997D38001
Additional Manual
MODEL CODE: 09R722

FX3U-ENET-L
User's Manual

Description
This manual

FX3U-ENET-L
INSTALLATION MANUAL

JY997D37801
Supplied with product

Installation of FX3U-ENET-L

FX3U Series
HARDWARE MANUAL

JY997D18801
Supplied with product

Extracts the I/O specifications, wiring, and
installation of FX3U Series PLC from FX3U Series
User's Manual - Hardware Edition.

JY997D16501
Additional Manual
MODEL CODE: 09R516

Explains FX3U Series PLC specification details for
I/O, wiring, installation, and maintenance.

FX3U Series User's Manual
- Hardware Edition
FX3UC(D, DSS) Series
HARDWARE MANUAL

JY997D28601
Supplied with product

Extracts the I/O specifications, wiring, and installation
of FX3UC(D, DSS) Series PLC from
FX3UC Series User's Manual - Hardware Edition.

FX3UC-32MT-LT-2
HARDWARE MANUAL

JY997D31601
Supplied with product

Extracts the I/O specifications, wiring, and
installation of FX3UC-32MT-LT-2 from FX3UC Series
User's Manual - Hardware Edition.

FX3UC Series User's Manual
- Hardware Edition

JY997D28701
Additional Manual
MODEL CODE: 09R519

Explains FX3UC Series PLC specification details for
I/O, wiring, installation, and maintenance.

FX3G/FX3U/FX3UC Series
Programming Manual
- Basic & Applied Instruction
Edition

JY997D16601
Additional Manual
MODEL CODE: 09R517

Describes PLC programming for basic/ applied
instructions and devices.

FX Configurator-EN-L
Operation Manual

JY997D38401
MODEL CODE: 09R929

The operation method of FX Configurator-EN-L

How to obtain manuals
For the necessary product manuals or documents, consult with the Mitsubishi
Electric dealer.

A-9

A-9

Applicable Standard
Certification of UL, cUL standards
The following product has UL and cUL certification.
UL, cUL File Number: E95239
Models: MELSEC FX3U series manufactured
FX3U-ENET-L
Regarding the standards that comply with the main unit, please refer to either the FX
series product catalog or consult with your nearest Mitsubishi product provider.
Compliance with EC directive (CE Marking)
This note does not guarantee that an entire mechanical module produced in
accordance with the contents of this note will comply with the following standards.
Compliance to EMC directive and LVD directive of the entire mechanical module
should be checked by the user / manufacturer. For more details please contact the
local Mitsubishi Electric sales site.
Regarding the standards that comply with the main unit, please refer to either the FX
series product catalog or consult with your nearest Mitsubishi product provider.

Requirement for Compliance with EMC directive
The following products have shown compliance through direct testing (of the
identified standards below) and design analysis (through the creation of a technical
construction file) to the European Directive for Electromagnetic Compatibility
(2004/108/EC) when used as directed by the appropriate documentation.
Attention
• This product is designed for use in industrial applications.
• Manufactured by:
Mitsubishi Electric Corporation
2-7-3 Marunouchi, Chiyoda-ku, Tokyo, 100-8310 Japan
• Manufactured at:
Mitsubishi Electric Corporation Himeji Works
840 Chiyoda-machi, Himeji, Hyogo, 670-8677 Japan
• Authorized Representative in the European Community:
Mitsubishi Electric Europe B.V.
Gothaer Str. 8, 40880 Ratingen, Germany
Type: Programmable Controller (Open Type Equipment)
Models: MELSEC FX3U series manufactured
from October 1st, 2009
FX3U-ENET-L
Standard

Remark

EN61131-2:2003
Programmable controllers
- Equipment requirements and tests

Complies with all relevant aspects of the following standards.
EMI
• Radiated Emissions
• Conducted Emissions
EMC
• Radiated electromagnetic field immunity
• Fast Transient burst
• Electrostatic discharge
• High-energy surge
• Voltage drops and interruptions
• Conducted RF
• Power frequency magnetic field

A - 10

A - 10

Caution to conform with EC Directives
• Installation in Enclosure
Programmable logic controllers are open-type devices that must be installed and
used within conductive control cabinets. Please use the programmable logic
controller while installed within a conductive shielded control cabinet. Please secure
the cabinet door to the control cabinet (for conduction).
Installation within a control cabinet greatly affects the safety of the system and aids
in shielding noise from the programmable logic controller.
• Control cabinet
- The control cabinet must be conductive.
- Ground the control cabinet with the thickest possible grounding cable.
- To ensure that there is electric contact between the control cabinet and its door,
connect the cabinet and its doors with thick wires.
- In order to suppress the leakage of radio waves, the control cabinet structure must
have minimal openings. Also, wrap the cable holes with a shielding cover or other
shielding devices.
- The gap between the control cabinet and its door must be as small as possible by
attaching EMI gaskets between them.

Shielding cover
Shielded cable

Wires*1

EMI gasket

*1. These wires are used to improve the conductivity between the door and control
cabinet.

A - 11

A - 11

The Manual's Usage and Structure

How to use this manual
In this manual, explanations are given for each application of the Ethernet modules
(FX3U-ENET-L).
Please use this manual using the following key items below as a reference.

(1) Features and utility lists
(a) Features and functions
• Chapter 1 describes the features of the Ethernet modules.
• Chapter 3 describes the common functions and specifications of the
Ethernet modules.
(b) Items included in this package and network configured items
• Section 2.2 describes the system configuration of the Ethernet module.
Parts and components other than those packaged with the module must
be purchased separately by the user.

(2) Processing required prior to starting the operation of the Ethernet
module
(a) Startup procedure
• Section 4.2 describes an outline of the procedures to do before starting the
operation of the Ethernet module.
(b) Connection to the Ethernet network.
• Section 2.2 describes the devices required to connect to the Ethernet
network.
• Section 4.4 describes the connection methods for each type of interface.
(c) Parameter settings required before starting Ethernet module operation
• Section 3.6 describes the parameter settings required in order to use each
function.
Confirm the required parameters, set them according to the relevant
section, and save the setting values in the PLC to which the Ethernet
module is installed.
• Section 4.5 describes the types of Ethernet parameter setting in order to
use the Ethernet module.
(d) Checking for Ethernet module failures
• Section 4.7 describes the self-diagnostic test for the Ethernet module.
(e) Checking for connection errors with the external devices
• Subsection 5.4.1 describes how to check for connection errors using the
"PING" command.
• Subsection 5.4.2 describes how to check for connection errors by
performing the loopback test through MC protocol-based communication.

A - 12

A - 12

(3) Connection between the Ethernet module and external devices
(a) Communication procedures
• Section 5.1 describes an outline of the communication procedures
(b) Connections with the external devices
• Section 5.6 describes the connections (open and close processing) for
each communication method (TCP/IP) and the open method (Active,
Passive), including programming procedures.

(4) Details on the data communication functions
(a) Communication functions
• Section 1.2 describes an overview of the Ethernet module communication
functions and related section numbers that can be referenced for more
detailed explanations.

(5) Data communication functions and programming
(a) Reading from and writing to the PLC
• Data is read from and written to the PLC with communication functions
using MC protocol.
• Chapter 8 is an overview of the communication functions using MC protocol.
• Chapter 9 is a detail on the communication functions using MC protocol.
(b) Sending and receiving data between the PLC and the external devices
• Data communication between the PLC and external devices is performed
with the fixed buffer communication functions.
• Chapters 6 and 7 explains the communication functions and programming
using the fixed buffers.

(6) Checking for error occurrences and taking corrective actions
(a) Error codes
• Chapter 11 describes troubleshooting, how to check for errors, and the
contents and reference for error codes.
(b) Error code storase area in the buffer memory of the Ethernet module
• Section 11.3 describes the error code storage areas in the buffer memory.

FX Configurator-EN-L (FX3U-ENET-L Configuration tool)
Using FX Configurator-EN-L to set parameters, the sequence programs for
communicating with external devices can be simplified.
For details on the parameter settings from FX Configurator-EN-L, refer to the FX
Configurator-EN-L operation manual.

A - 13

A - 13

About the Generic Terms and Abbreviations
This manual uses the following generic terms and abbreviations to describe the
Model FX3U-ENET-L Ethernet interface block.
Generic Term/Abbreviation

Description

Ethernet Address

A machine-specific address that is also referred to as the MAC (Media Access Control
Address). This is used to identify the addresses of external devices over a network.
The Ethernet address of the Ethernet module can be verified on BFM.

Ethernet module

Abbreviation for the FX3U-ENET-L Ethernet Interface block
(Described as the Ethernet module or FX3U-ENET-L in the figures)

Ethernet network

Abbreviation for 10BASE-T and 100BASE-TX networks

GX Developer

Abbreviation for GX Developer (SWnD5C-GPPW-E). (n in the model name is 4 or later)

External device

Generic term for personal computers, computers, workstations (WS) and Ethernet
module etc. that are connected by Ethernet for data communication

Personal computer

Generic term for an IBM PC/AT (or IBM compatible) personal computer

Main unit

Generic name for FX Series PLC main unit

FX Configurator-EN-L

Software for setting the Ethernet module parameters. FX Configurator-EN-L (FX3UENET-L Configuration tool) can set the independent startup method, and the startup
method from the [tool] menu in GX Developer.

A - 14

A - 14

1

OVERVIEW

MELSEC-F

1 OVERVIEW
This manual provides information on the specifications of the Ethernet interface block,
FX3U-ENET-L (hereinafter called FX3U-ENET-L or the Ethernet module), as well as
the procedures before starting operation, the control procedures and data
communication method for communicating with external devices, maintenance,
inspection, and troubleshooting.
When the program examples introduced in this manual are applied to an actual
system, examine the safety of the control in the target system before use.

1.1 Overview of the Ethernet Module
The Ethernet module is an interface module on the PLC side for connecting the FX3U/
FX3UC series PLC with the host system, such as a personal computer work station,
and other PLCs using the TCP/IP or UDP/IP communication protocol via Ethernet
(100BASE-TX, 10BASE-T).
Internet
(Public dial-up line)

Internet service
Provider

Internet service
Provider

Network Range (Only within LAN)

Mail server

Router

Router

Hub

Hub

Mail server

External device

Local
station
External device

GX Developer

1-1

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OVERVIEW

MELSEC-F
1) Collection and modification of PLC data
(Communication using the MELSEC Communication Protocol (referred
to below as the MC Protocol))
2) Transmission and reception of arbitrary data to/from external devices
(Communication using fixed buffers)
3) Data transmission by e-mail
(When using the e-mail function)

1

POINT
The module operation is not guaranteed if any of the following connection is
used. Check the module operation on the user side.
• Connections using the Internet (general public line) (Connections using
Internet connection service provided by Internet service providers and
telecommunications carriers)
• Connections using devices in which a firewall is installed
• Connections using broadband routers
• Connections using wireless LAN

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OVERVIEW

MELSEC-F

1.2 Features of the Ethernet Module
(1) Data communication using MC protocol (Details are explained in
Chapter 8 and Chapter 9)

Response

Command

Using MC protocol, the device data of the PLC can be read from/written to the
host system.
This protocol is a passive protocol that communicates data solely according to
the requests from the host system. It does not require a sequence program for
data communication after a connection is established.

Local station
External device

(2) Communication using fixed buffers (Details are explained in
Chapters 6 and 7)
With communication using fixed buffers, a maximum of 1023 words of arbitrary
data can be sent or received between PLCs or between the PLC and an arbitrary
device.
An Ethernet module is provided with 2 fixed buffer data areas each with 1023
word storage space, and each is assigned as either a sending or receiving buffer
for an arbitrary device.
Since communication using MC protocol is passive, communication using fixed
buffers is an active protocol. Data can be sent from the PLC side to another PLC
and an arbitrary device when equipment errors occur or when some specified
conditions are satisfied.
Receive/send

External device

Receive/send

Local station

External device

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MELSEC-F
(3) Sending by e-mail (Details are explained in Chapter 10)
In "E-mail send", data can be sent to and from an external device at a remote
location using e-mails via an internet connection.
(a) Sending e-mail from the PLC
The following data can be sent by e-mail.
1) Sending data as attached files
Up to 2k words of data can be sent to from a personal computer or other
Ethernet module with mail function as a file attached to an e-mail.
2) Sending data as main text
Up to 256 words of data can be sent to a personal computer or portable
terminal in the main text of an e-mail.
Internet
(Public dial-up line)

E-mail
sending

Internet service
provider

Internet service
provider

Router

Router

Hub

Hub

Mail server
Mail server

Mail send

Local station

External device

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MELSEC-F
(4) Connecting FX Configurator-EN-L (Details are explained in the
Operating Manuals for FX Configurator-EN-L)
(a) Simplifying sequence programs using FX Configurator-EN-L
FX Configurator-EN-L supports the parameter setting function to perform the
Ethernet module initialization and the open processing with external devices.
By setting up the following parameters with FX Configurator-EN-L, access is
enabled from the external device to the PLC. It can also simplify sequence
programs used to perform communication by Ethernet modules.
• IP address setting
• E-mail settings
• Port number setting
• Each timer setting
• Protocol type setting
For more information on setting up the Ethernet module, see Section 3.5,
"List of Setting Items for Ethernet Modules" and other applicable reference
sections.

External device

Local station

External device

Parameter setting
Ethernet*1
Serial communication*2

FX Configurator-EN-L

*1 Access is enabled only when MELSOFT connection is set in the open
method of the Ethernet module.
*2 The open settings is not set for the initial state of the Ethernet module.
Set it through serial communication.

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MELSEC-F
(b) Connecting multiple MELSOFT products (GX Developer, MX Component)
This product can be connected with one or more MELSOFT product, via
TCP/IP communication (through the in-house LAN, etc.) or UDP/IP
communication (through the in-house LAN, etc.).
1) Connection via TCP/IP communication
• If a MELSOFT product is to be connected with the FX ConfiguratorEN-L open settings, a maximum of two units can be connected with
MELSOFT product.
• If a MELSOFT product is to be connected, the settings of buffer
memory for the MELSOFT connection or the following settings using
FX Configurator-EN-L are required.
For FX Configurator-EN-L, on the "Open settings" screen, set "TCP" in
the protocol field of the connection number to be used, and "MELSOFT
connection" in the open method field. (See Section 5.5.)
(External device)

(Protocol used)

Connection via TCP/IP communication only
Multiple units (Maximum two units)
For use when the user specifies a MELSOFT
connection.
"Ethernet open setting" parameter is needed.

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MELSEC-F

1.3 Software Configuration
The Ethernet modules support the TCP/IP and UDP/IP protocols.
Personal computer/work-station(example)

OSI reference model corresponding to the PLC configuration

PLC

(Layers)

Main Unit

User program

PLC
FROM/TO instruction
Buffer memory
System call
Communication
using fixed buffers

Communication
using the MC protocol

Communication
by e-mails

7
6
5

Application layer
Presentation layer
Session layer

4

Transport layer

3

Network layer

2
1

Data link layer
Physical layer

SMTP
POP3
DNS

Ethernet
module

Socket
TCP

UDP

IP

TCP/UDP

ICMP

IP

ARP
Ethernet
(100BASE-TX, 10BASE-T)

ICMP
ARP

Ethernet
(100BASE-TX,10BASE-T)

(1) TCP (Transmission Control Protocol)
This protocol guarantees data credibility and reliability in communication between
a personal computer/work station and PLC that are connected via network, and
provides the following functions:
• Creates a logical connection by establishing a connection (logical line) as if a
dedicated line was created between external devices.
• Up to 4 connections can be established and communicated with at the same
time in the Ethernet module.
• Data reliability is maintained by the sequence control using the sequence
numbers, the data retransmission function and the check sum.
• The communication data flow can be controlled by operations using Windows.

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(2) UDP (User Datagram Protocol)
This protocol may not guarantee data credibility or reliability in communication
between a personal computer/work station and PLC that are connected via
network. Thus, even if the data does not reach the target node, it will not be
retransmitted.
• Because it is connectionless, communication efficiency is much improved than
TCP/IP.
• A check sum is used to increase the reliability of the communication data.
When greater reliability must be maintained, a user application or TCP should
be used for retrying operation.

(3) IP (Internet Protocol)
• Communication data is sent and received in datagram format.
• Communication data can be divided and reassembled.
• Routing option is not supported.

(4) ARP (Address Resolution Protocol)
• This protocol is used to get the Ethernet physical addresses from the IP
addresses.

(5) ICMP (Internet Control Message Protocol)
• This protocol is used to exchange errors which occur on an IP network and
various information related to the network.
• Provides a function to transmit IP error messages.
• See Appendix for information regarding the types of ICMP supported.

(6) DNS (Domain Name System)
• This system translates IP addresses to names that are easy to remember by
the user.

(7) SMTP (Simple Mail Transfer Protocol)
• This protocol transfers mail.

(8) POP3 (Post Office Protocol Ver. 3)
• This protocol transfers mail received by a mail server to a local computer.

(9) Flag bit of TCP/IP (SYN, ACK, PSH, FIN, RST, and URG)
In communication using TCP, these flag bits indicate segments where
connection/disconnection or response confirmation is executed or emergency
data is included.
1) SYN (Synchronized Flag)
When this bit is ON (1), it indicates that the initial sequence number value
is set in the sequence number field.
This bit is used when the connection is newly opened.
2) ACK (Acknowledgment Flag)
When this bit is ON (1), it indicates that ACK (confirmation response
number) field is valid.
It also indicates that this segment includes the information on response
confirmation.
When this bit is OFF (0), it indicates that ACK (confirmation response
number) field is invalid.

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OVERVIEW

MELSEC-F
3)

4)

5)

6)

1-9

PSH (Push Flag)
When this bit is ON (1), the host that has received this segment sends the
data to the upper application with high priority.
This bit is to be turned ON when the data should be sent to an external
device as soon as possible.
When this bit is OFF (0), the timing when the received data is sent to the
upper application depends on the TCP layer of the receiving side.
FIN (Fin Flag)
When this bit is ON (1), it indicates that there is no more data to be sent
from the segment source and that the send source wants to disconnect.
However, data can be received from the external device.
The connection is on until the segment whose FIN bit is ON is received
from the external device.
RST (Reset Flag)
When this bit is ON (1), the host from which the segment has sent
disconnects unilaterally (forcibly).
Disconnection by this method is used when an unrecoverable error with
the normal method has occurred or when the host has been restored after
being down.
URG (Urgent Flag)
When this bit is ON (1), it indicates that this data segment includes the
emergency data flag.

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2

SYSTEM CONFIGURATIONS

MELSEC-F

2 SYSTEM CONFIGURATIONS
This section explains the system configurations that may be combined with the
Ethernet modules.

2

2.1 Applicable Systems
Ethernet modules can be used with the following systems:

(1) Applicable PLC and number of modules that can be mounted
The following table lists the PLC where the Ethernet module can be mounted and
the number of modules that can be mounted.
Series name

Compatible version

Number of I/O points
occupied

Number of modules that can
be mounted

FX3U

System version V2.21 or
more

8 points for input or output

1

FX3UC
(An FX2NC-CNV-IF or
FX3UC-1PS-5V is necessary)

System version V2.21 or
more

8 points for input or output

1

(2) Applicable software packages
When using the Ethernet module, the FX Configurator-EN-L for software
packages applicable to the Ethernet module can be used.
Refer to the manual of FX Configurator-EN-L for the details.

1) The Ethernet module is set with FX Configurator-EN-L
[Configurable by BFM].
2) To use FX Configurator-EN-L, either of the following software
should be installed.
• GX Developer (V 8.88S or later)

3) For starting FX Configurator-EN-L, the following shows two
kinds of methods.
• Independently starting FX Configurator-EN-L
• Starting from [Tools] menu of GX Developer

4) The installation form of FX Configurator-EN-L differs depending on sales territory or country of this product.
Consult with the dealer of this product for details.

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SYSTEM CONFIGURATIONS

MELSEC-F

2.2 Devices Required for Network Configuration
This section explains the devices that are required to configure a network.
Network installation work requires sufficient safeguard; ask a network specialist for
installation.
When connecting FX3U-ENET-L to a network, either a 10BASE-T or 100BASETX can be used.
The Ethernet module detects whether it is 10BASE-T or 100BASE-TX, and the
full-duplex or half-duplex transmission mode according to the hub.
For connection to the hub without the auto detection function, set the half-duplex
mode on the hub side.

(1) Connection using the 100BASE-TX
Hub
Twisted pair cable

* Up to 2 levels are allowed
for cascade connection
External device

Ethernet module

Use devices that satisfy the standards of IEEE802.3 and 100BASE-TX.
• Shielded twisted pair cable (STP cable), category 5
* Straight cables can be used.
(Correct operation is not guaranteed if a crossed cable is used to connect to
an external device via the 100BASE-TX of the Ethernet module. However, it
is possible to use crossed cables to connect two Ethernet modules for data
communication or to connect an Ethernet module.)
• RJ45 plug
• 100Mbps hub

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SYSTEM CONFIGURATIONS

MELSEC-F

(2) Connection using the 10BASE-T
Hub
Twisted pair cable

* Up to 4 levels are allowed
for cascade connection
External device

Ethernet module

Use devices that satisfy the standards of IEEE802.3 and 10BASE-T.
• Shielded twisted pair cable (STP cable), category 3 (4, 5)
* Straight cables can be used.
(Correct operation is not guaranteed if a crossed cable is used to connect to
an external device via the 10BASE-T of the Ethernet module. However, it is
possible to use crossed cables to connect two Ethernet modules for data
communication or to connect an Ethernet module.)
• RJ45 plug
• 10Mbps hub

POINT
• During the high-speed communication (100 M bps) via 100BASE-TX
connection, a communication error may occur due to the effect of high
frequency noise from devices other than PLC in a given installation
environment.The following describes countermeasures on the FX3U-ENET-L
side to prevent the effect of high frequency noise for construction of a network
system.
(1) Wiring connection
• Do not bundle the twisted pair cables with the main circuit and power wires,
and do not install them close to each other.
• They should be installed at least 100 mm (3.94 in) away from each other.
• Make sure to place the twisted pair cables in a duct.
(2) Communication method
• Data communication with an external device is performed using TCP/IP
communication.
• Increase the number of communication retries as necessary.
[When the error cannot be solved]
• Communication is performed at a data transmission rate of 10 M bps by
changing the connection hub for the FX3U-ENET-L to a hub capable of
handling 10 M bps.

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SPECIFICATIONS

MELSEC-F

3 SPECIFICATIONS
This section explains the Ethernet module performance specifications and
transmission specifications.
For the general specifications, refer to the packaged manual and the User’s Manual of
the PLC main unit.

3.1 Performance Specifications
The following explains the performance specifications of the Ethernet module.
Item
100 M bps

Communication mode
Transmission
specifications

Base band

Maximum segment length

Number of simultaneously open
connections allowed

100 m (328' 1") *1
Cascade connection Maximum 2 stages

Cascade connection Maximum 4 stages

4 connections
Fixed buffer communication: up to 2 connections (C1 and C2)
MELSOFT connection + MC protocol: up to 2 connections (C3 and C4)

Fixed buffer
E-mail

10 M bps
Full-duplex/Half-duplex

Transmission method
Maximum number of
nodes/connection

Transmission
data storage
memory

3

Specification

Data transmission speed

1023 word

2

Attached file

2048 words

1

Main text

256 words

1

Number of I/O occupied points

8 points

Power supply

24V DC +20%, -15%, ripple (p-p) less than 5%

Allowable instantaneous power failure time

Operation can be continued upon occurrence of instantaneous power failure for 1 ms or less.

External 24V current consumption

240 mA

Number of connectable units to the main unit

1
FX3U/FX3UC PLC
Ver. 2.21 or later

Applicable PLC
External dimensions

90 (3.55") (H)

Weight

55 (2.17") (W)

87 (3.43") (D) [mm] (inches)

0.3 kg (0.66 lbs)

*1 Length between the Hub and node.

POINT
The module operation is not guaranteed if any of the following connection is
used. Check the module operation on the user side.
• Connections using the Internet (general public line) (Connections using
Internet connection service provided by Internet service providers and
telecommunications carriers)
• Connections using devices in which a firewall is installed
• Connections using broadband routers
• Connections using wireless LAN

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Item
Data size

Specification
Attached file

2048 words

1

Main text

256 words

1

Data transfer method

When sending: Sends either a file as attachment or main text (select one).

Subject

US-ASCII format or ISO-2022-JP (Base64)

Attached file format

MIME format

MIME

Version 1.0
Binary/ASCII/CSV can be selected.
File name: XXXX.bin (binary), XXXX.asc (ASCII), XXXX.csv (CSV)
(CSV: Comma Separated Value)

Data of attached file format

3

E-mail
Transmission
specifications
Transmission
data

Division of attached file

Cannot be divided (only one file can be sent)

When sending (encode)

Subject
: Base64/7 bits
Main text
: 7 bits
Attached file : Base64

Encryption

No

Compression

No
Port number

Communication with mail server

SMTP
Authentication method
POP

Operation check mailer

Port number*1
Microsoft

1 to 65535

SMTP: 25 (initial)
SMTP-AUTH: 587

• No authentication
• SMTP-AUTH (PLAIN, LOGIN, CRAM-MD5)
• POP before SMTP
1 to 65535

POP3: 110 (initial)

Corporation (Outlook

Express 6.0)

*1 The setting is required only when "POP before SMTP" is selected in the SMTP authentication method.

NOTE
The following explains each of the transmission specification items.
[Connecting using the 10BASE-T]

[Connecting using the 100BASE-TX]
Hub

Hub

Up to
4 levels

3-2

Maxmum 100m

Maxmum
100m

Maxmum 5m

Maxmum
100m

Up to (2) levels are
allowed for cascade
connection.

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3.2 Data Codes for Communication
This section explains the data codes used in the communication between the
Ethernet module and the external device or the PLC.
(1) The data codes used while communicating are listed below.
1) Ethernet module External device
Data can be communicated by selecting either binary code or ASCII code
in the data code setting of FX Configurator-EN-L or the PLC, as shown
below.
For more details about binary code/ASCII code changeover, refer to
Section 4.6, "Communication Settings".
Data communication function

Communication data code
Binary code

ASCII code

Communication using MC protocol
Communication using fixed buffer

Reference chapter
Chapter 8,9

Procedure exist
No procedure

Chapter 6
1

(* )

—
: Selectable

Chapter 7
: Cannot be communicated

*1 Communication is performed in binary code regardless of the communication code setting.

NOTE
When sending e-mail, communication is performed using the data code handled by
each function, regardless of the setting of the communication data code.

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2) Ethernet module PLC
Data is sent and received in binary code.
Ethernet module
Binary code
Binary code

PLC

Communication
data
storage
area

External
device
BIN/ASCII
conversion

ASCII code

(2) When communicating using ASCII code, 1-byte binary code data is automatically
converted into 2-byte ASCII code data and then transmitted.
(Example)
Binary code data

ASCII code data

15 H
(One byte)

31H ,35 H
"1","5"
(Two bytes)

1234H
(Two bytes)

31H ,32 H ,33H ,34H
"1","2","3","4"
(Four bytes)

(3) The amount of data that can be communicated at one time between the Ethernet
module and an external device is determined by the function used and the data
code (binary of ASCII) selected in "Operation setting" - "Communication data
code setting" of the FX Configurator-EN-L.
The following shows the maximum sizes of communication data that can be sent
at a time with each data communication function.
Data communication function
Communication using MC protocol
Communication using fixed buffer

Sending by e-mail

3-4

Exchangeable data size
The maximum number of point that can be designated
with each command/instruction : Maximum of 32 words

Procedure exist
No procedure

1017 words (Binary code)

508 words (ASCII code)

2046 bytes
Attached file : Maximum of 2048 words
or
Main text : Maximum of 256 bytes

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SPECIFICATIONS

MELSEC-F

3.3 Relationship between the External Devices and Additional Functions for Each
Communication Function
This section explains which external devices data communication can be performed
with and which additional functions can be used for each function.

(1) Communicability with external devices using various functions
The following table lists the communicability with external devices using various
functions.
External device
Function

Personal computer

Personal computer

FX3U-ENET-L

FX3U-ENET-L

QJ71E71

FX3U-ENET-L

FX3U-ENET-L

FX3U-ENET-L

QJ71E71

FX3U-ENET-L

Communication using MC protocol
Communication using the fixed buffer
*1

Sending/receiving e-mail

*1

: Can communicate

: Cannot communicate

FX3U-ENET-L: FX Series Ethernet interface module
QJ71E71: Q Series Ethernet interface module
*1 The mail server is required separately.

(2) Relationship with additional functions
The following table lists the correspondence between functions and their
additional functions that can be used.
Additional function
Communication function

Router relay
communication
(router relay function)

Existence check of
external device

Communication method
Communication via pairing
open

TCP/IP

UDP/IP

Communication using MC protocol
Communication using
the fixed buffer

Procedure exist
No procedure

Sending e-mail
: Available

3-5

: Not available or this function does not correspond to any of the functions in the function column.

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3.4 Ethernet Module Function List
This section shows a list of Ethernet module functions.

(1) Basic functions of the Ethernet module
The Ethernet module can perform the communications shown in the table below
via TCP/IP or UDP/IP communication.
Function
Communication using
MC protocol

Description

Reference section

Subset of A
compatible 1E

Reads/writes PLC data from/to an external device.

Chapter 8, 9

frame

Communication using

Procedure exist Sends/receives arbitrary data between the PLC and the

the fixed buffer

No procedure

Sends data via e-mail.

Sending e-mail

Chapter 6

external device using the fixed buffer of the Ethernet module. Chapter 7
Chapter 10

• Sending by the PLC

(2) Additional functions of the Ethernet module
The following table lists the additional functions of the Ethernet module that can
be used.
Function

Description

Reference section

Router relay communication (router relay
function)

Performs data communication via a router or gateway. (The router
relay function is not a function by which the Ethernet module works as
a router.)

Section 5.3

Existence check of external device (Existence
check function)

Checks whether or not the external device is working normally after a
connection is established (open processing).

Subsection 5.2.2 and
Section 5.5

Communication via pairing open

Pairs and then opens a reception connection and a transmission
connection (for fixed buffer).

Section 5.7

MELSOFT connection (GX Developer, etc.)

Connects MELSOFT products (GX Developer, etc.) via TCP/IP
communication (through the in-house LAN, etc. ). It is possible to
connect multiple MELSOFT products at the same time. It is also
possible to connect multiple MELSOFT products simultaneously.

Section 1.2 (4)
Manual of each
MELSOFT product

(3) Status check of the Ethernet module
Checks that the Ethernet module is working and can communicate normally.
Function
Self loopback test
Hardware test

Description
Checks the Ethernet module's sending/receiving function and line
connection status.
Tests the RAM and ROM of the Ethernet module.

Reference section
Subsection 4.7.1
Subsection 4.7.2

When a data communication error occurs, this function stores the
Communication error storage

error information (error log), including the message subheader and
IP address of the external device for a maximum of 16 pairs in the

Chapter 11

buffer memory.

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3.5 List of Setting Items for Ethernet Modules
The following table lists the parameter setting items that are set using Ethernet Module.
Function and parameter setting
Parameter setting item

requirement (*1)

Description of setting
MC

Fixed

Mail

MELSOFT

Reference
section

Ethernet module settings

Settings for using the Ethernet module as a network
module.

Section 4.5

Operational settings

Set the common items between the modules.
These settings are required for the initial processing.

Section 4.6

Initial settings

Set the data communication timer values.
Set the DNS server's IP address.

*2
—

*2

*2

—

*2
—

Open settings

Set up the open processing for connection in order to
perform data communication with the external device.

Router relay parameter

Set the router relay of Ethernet.

E-mail settings

Perform settings for sending e-mail.

—

—

—

Set the destination mail address.

—

—

—

Send mail address
setting

—

Section 5.2
Section 10.6
Section 5.5
Section 5.3

: Must be set when the applicable function is used.

: Set as needed

Section 10.6

: Setting is not required.

*1 The meanings of the abbreviations used in the table above are as follows:
MC: Communication using MC protocol
Mail: E-mail
Fixed: Communication using the fixed buffer
*2 Setting is not necessary if initial values are being used.

POINT
Parameters set in FX Configurator-EN-L are saved in the Ethernet module's flash
ROM.

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3.6 List of Applications and Assignments of the Buffer Memory
Data transmission/reception between Ethernet Module and PLC is performed via the
Ethernet Module buffer memory (hereinafter called BFM).
Reading/writing data in the buffer memory from the PLC must be performed by the
FROM/TO instructions (instructions that can access BFM).
In addition, the initial value of the buffer memory or the internally stored value is
written when the power is turned on.

(1) Configuration of the buffer memory
Buffer memory consists of a user area and a system area, as listed below.
(a) User areas
1) The areas where the user writes/reads data.
2) A user area consists of a parameter area for initial processing and data
communication, an area for data communication, and an area for storing
communication status and communication error data.
3) Reading/writing data to the user area should be performed according to
the instructions in the corresponding detailed explanation section.
Data communication may take longer if continually executed; therefore,
execute only when needed.
(b) System areas
The areas used by the Ethernet module

Important
Do not write data in the "system areas" of the buffer memory.
If data is written to any of the system areas, the PLC system may not operate
properly.
When writing a value to the buffer memory including "System Area," pay close
attention not to change the system bit.

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(2) Assignments of the buffer memory
A buffer memory consists of 16 bits per address.

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

The following shows the buffer memory addresses.
(a) Initial processing parameter (BFM #0 to 31)
BFM number
Decimal
(Hexadecimal)
0 to 1
(0 to 1H)

2
(2H)

Attribute
*

1

Name

Initial value
Decimal
(Hexadecimal)

Local station Ethernet module IP address (Initial value 192.168.1.254)

3232236030
(C0A801FE H)

Application

R/W

Special function settings
• Router relay function (b5, b4)
00: Do not use (initial)
01: Use

R/W

Flash ROM
2

save (* )

Reference
section

Section 4.6

Section 5.3

0
(0000 H)

Bits other than above are reserved for system use.
3
(3H)

—

4
(4H)

R/W

TCP ULP (existence function) timer value
Setting time = setting value 500 ms

60
(3C H)

5
(5H)

R/W

TCP zero window timer value
Setting time = setting value

500 ms

20
(14 H)

6
(6H)

R/W

TCP resend timer value
Setting time = setting value

500 ms

20
(14 H)

7
(7H)

R/W

TCP end timer value
Setting time = setting value

500 ms

40
(28 H)

8
(8H)

R/W

IP assembly timer value
Setting time = setting value

500 ms

10
(A H)

9
(9H)

R/W

Response monitoring timer value
Setting time = setting value 500 ms

60
(30 H)

10
(AH)

R/W

Destination existence confirmation starting interval
Setting time = setting value 500 ms

11
(BH)

R/W

Destination existence confirmation interval timer
Setting time = setting value 500 ms

20
(14 H)

12
(CH)

R/W

Destination existence confirmation resend timer

3
(3 H)

13 to 23
(D to 17H)

—

24
(18H)

R/W

System area

Initial
processing
parameter
setting area
Monitoring timer

—

System area

Initial processing
parameter
setting area

Communication condition setting (Operational Settings) area
• Communication data code setting (b1)
0: Communication in binary code
1: Communication in ASCII code
• TCP Existence confirmation setting (b4)
0: Use the Ping
Communication
1: Use the KeepAlive
condition setting
• Send frame setting (b5)
area
0: Ethernet frame
(Operational Set1: IEEE 802.3 frame
tings)
• Initial timing setting (b8)
0: Do not wait for OPEN (communication
impossible at STOP time)
1: Always wait for OPEN (communication
possible at STOP time)
Bits other than above are reserved for system use.

—

—

Section 5.2

1200
(480 H)

—

—

0
(0H)

—

Section 4.6

(Continues on the next page)
*1 Attribute R : Read, W : Write, — : Use prohibited
*2 Saving to Flash ROM from FX Configurator-EN-L allowed/prohibited
(Settings are saved in the flash ROM of the Ethernet module.)
: Setting allowed

3-9

: Setting prohibited

3-9

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Attribute
Decimal
(Hexadecimal)

Application

Name

Initial value
Decimal
(Hexadecimal)

Flash
ROM
save

Reference
section

Flash ROM writing control
0000H: Normal status

25
(19H)

Flash ROM
writing control
area

R/W

Flash ROM
control

9872H: Write command for configuration data
to a flash ROM.
Automatically returns to 0000H after
writing to a flash ROM

0
(0000H)

9981H: Write command for configuration data
to a flash ROM (return to the status at
factory shipment).
Automatically returns to 0000H after
writing to a flash ROM

—

Flash ROM writing status

26
(1AH)

R/W

27
(1BH)

R

Flash ROM
writing status

Initial completion

0000H:
9981H:
0001H:
0002H:

Initial status
During the flash ROM writing
Flash ROM writing completion
Flash ROM writing error (Flash ROM
fault)
The status is updated by write command

0000H: Initial incompletion
0001H: Initial completion (in conjunction with b0 of BFM#28)

0
(0000H)

0
(0000H)

Subsection
5.2.1

0
(0000H)

Section 4.3

0
(0000H)

Section
11.3

7132
(1BDCH)

—

Stores Ethernet module status
b0: INIT 1: Initial processing normally completed
0: —
b1: System bit
b2: 100M/10M 1: 100Mbps
0: 10Mbps/When not connected
b3: ERR. 1: Setting abnormal display
0: Setting normal display
b4: COM.ERR 1: Communication abnormal display
0: Communication normal display
b5: 1: Initial processing abnormally completed
0: —
b6: 1: Open processing abnormally completed
0: —
b7: 1: Link signal ON 0: Link signal OFF
b8: Connection No.1 1: Open 0: Closed
b9: Connection No.2 1: Open 0: Closed
b10: Connection No.3 1: Open 0: Closed
b11: Connection No.4 1: Open 0: Closed
b0 and b5 are cleared at re-initialization request.
b6 is cleared at open request.

28
(1CH)

R

29
(1DH)

R/W

Error code
storage

Stores the first error code (when the value of this BFM number is
0000H)
Writing 0000H resets the error.

30
(1EH)

R

Model code
storage

Model code (K7132)

31
(1FH)

—

System area

3 - 10

Module status
area

—

—

—

3 - 10

3

SPECIFICATIONS

MELSEC-F
(b) Communication parameter setting area (BFM #32 to 102)

BFM number
Attribute
Decimal
(Hexadecimal)

32
(20H)

33
(21H)

Application

R/W

Communication
parameters
setting area

Initial value
Flash
Decimal
ROM
(Hexadecimal) save

Name

Connection
usage setting
area

Connection No. 1
• Usage of fixed buffer (b0)
0: For sending or fixed buffer communication is
not executed
1: For receiving
• Destination existence confirmation (b1)
0: No confirm
1: Confirm
• Pairing open (b7)
0: No pairs
1: Pairs
• Communication method (protocol) (b8)
0: TCP/IP
1: UDP/IP
• Fixed buffer communication (b9)
0: Procedure exist
1: No procedure
• Open system (b15, b14)
00: Active open or UDP/IP
01: Use prohibited
10: Unpassive open
11: Fullpassive open
Bits other than above are reserved for system use.
Connection No. 2
(bit configuration is the same as connection No.1)
"0" must be selected in the pairing open setting (b7).

R/W

0
(0H)

Reference
section

Section 5.5

(same as connection No.1)

Connection No.3
Select either value shown in the table below when
selecting MC protocol.
Protocol

34
(22H)

Unpassive

R/W

TCP
Fullpassive
UDP

Existence
confirmation

Open system

—

Setting value

Performed

8403H

Not performed

8401H

Performed

C403H

Not performed

C401H

Performed

0503H

Not performed

0501H

(same as connection No.1)

Set "A002H" when selecting MELSOFT connection.
Any other value cannot be set.
35
(23H)

R/W

36 to 39
(24 to 27H)

—

Connection No. 4
(same as connection No.3)
System area

(same as connection No.1)
—

—

—

(Continues on the next page)

3 - 11

3 - 11

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Attribute
Decimal
(Hexadecimal)
40
(28H)

R/W

41 to 42
(29 to 2AH)

R/W

43
(2BH)

R/W

44 to 46
(2C to 2EH)

R/W

47 to 53
(2F to 35H)

R/W

54 to 60
(36 to 3CH)

Application

Connection
No. 1

Communication
parameters
setting area

Initial value
Decimal
(Hexadecimal)

Name

Communication
address setting
area

0
(0H)

Section 5.5

Destination IP address

0
(0H)

Section 5.5

Destination Port No.

0
(0H)

Section 5.5

Destination Ethernet address

(FFFFFFFFFFFFH)

(Same as connection No. 1)

R/W

Connection
No. 3

(Same as connection No. 1)

61 to 67
(3D to 43H)

R/W

Connection
No. 4

(Same as connection No. 1)

68 to 102
(44 to 66 H)

—

3 - 12

Reference
section

Local station Port No.

Connection
No. 2

System area

Flash
ROM
save

—

—

—

—

3 - 12

3

SPECIFICATIONS

MELSEC-F
(c) Communication status storage area (BFM #103 to 226)

BFM number
Attribute
Decimal
(Hexadecimal)

Application

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Name

Reference
section

103 to 104
(67 to 68H)

—

105
(69H)

R

106 to 107
(6A to 6BH)

R

108 to 110
(6C to 6EH)

R

111 to 119
(6F to 77H)

—

120
(78H)

R

Local station Port No.

0
(10H)

—

121 to 122
(79 to 7AH)

R

Destination IP address

0
(0H)

—

123
(7BH)

R

Destination Port No.

0
(0H)

—

124
(7CH)

R

Open error code

0
(0H)

Section 11.4

125
(7DH)

R

Fixed buffer sending error code*2

0
(0H)

Section 11.4

126
(7EH)

R

Connection end code

0
(0H)

Section 11.4

127
(7FH)

R

Maximum value

0
(0H)

—

128
(80H)

R

Minimum value

0
(0H)

—

129
(81H)

R

Current value

0
(0H)

—

130 to 139
(82 to 8BH)

R

Connection
No. 2

(Same as connection No. 1)

140 to 149
(8C to 95H)

R

Connection
No. 3

(Same as connection No. 1)

150 to 159
(96 to 9FH)

R

Connection
No. 4

(Same as connection No. 1)

160 to 199
(A0 to C7H)

—

System area

Area for initial
processing

—
0
(0H)

Section 11.4

Local station IP address

0*1
(0H)

—

Local station Ethernet address

0*1
(0H)

—

Connection
No. 1
Connection
information area

—

Fixed buffer
communication
time*2
(unit : 10ms)

System area

—

Initial error code

System area

Communication
status storage
area

—

—

—

—

—

—

(Continues on the next page)
*1 Initial processing writes IP and Ethernet address.
*2 Supported in connections No. 1 and 2 only.

3 - 13

3 - 13

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Attribute
Decimal
(Hexadecimal)
200
(C8H)

201
(C9H)

Application

Name

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Stores Ethernet module status
(The same specification as BFM#28 "Module status
area")

R

0*1
(0H)

Hub connection status area
• Communication mode (b9)
0: Half duplex
1: Full duplex
• Hub connection status (b10)
0: Hub not connected/disconnected
1: Hub connected
• Data transmission speed (b14)
0: Operating at 10BASE-T
1: Operating at 100BASE-TX

R

Reference
section

—

Section
5.8

—

Bits other than above are reserved for system use.

202
(D0H)

R

203
(CBH)

R

204 tos 226
(E0 to E2H)

—

Communication
status storage
area

Operation mode settings
0: Online
1: Offline
Module
2: Self loopback test
status area
3: Hardware test
4 to F: System area

0*2
(0H)

Status of settings
• Communication data code setting (b1)
0: Communication in binary code
1: Communication in ASCII code
• TCP Existence confirmation setting (b4)
0: Use the Ping
1: Use the KeepAlive
• Send frame setting (b5)
0: Ethernet frame
1: IEEE802.3 frame
• Initial timing setting (b8)
0: Do not wait for OPEN
(Communications impossible at STOP time)
1: Always wait for OPEN
(Communication possible at STOP time)
Bits other than above are reserved for system use.
System area

—

4
(04H)

—

Section
4.7

—

—

*1 It varies after initialization.
*2 Values written to BFM #202 will become active the next time the module is powered ON.
(The value returns to 0 when each running mode execution is complete.)

3 - 14

3 - 14

3

SPECIFICATIONS

MELSEC-F
(d) Error log partition area (BFM #227 to 511)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Name

Initial value
Decimal
(Hexadecimal)

Flash ROM
save

227
(E3H)

R

Number of error occurrences

228
(E4H)

R

Error log write pointer

229
(E5H)

R

Error code/end code

230
(E6H)

R

Subheader

231
(E7H)

R

Command code

232
(E8H)

R

233
(E9H)

R

234 to 235
(EA to EBH)

R

Destination IP address

236
(ECH)

R

Destination Port No.

237
(EDH)

R

System area

238 to 246
(EE to F6H)

R

Error log
block 2

(Same as error log block 1)

247 to 255
(F7 to FFH)

R

Error log
block 3

(Same as error log block 1)

256 to 264
(100 to 108H)

R

Error log
block 4

(Same as error log block 1)

265 to 273
(109 to 111H)

R

Error log
block 5

(Same as error log block 1)

274 to 282
(112 to 11AH)

R

Error log
block 6

(Same as error log block 1)

283 to 291
(11B to 123H)

R

Error log
block 7

(Same as error log block 1)

292 to 300
(124 to 12CH)

R

Error log
block 8

(Same as error log block 1)

301 to 309
(12D to 135H)

R

Error log
block 9

(Same as error log block 1)

310 to 318
(136 to 13EH)

R

Error log
block 10

(Same as error log block 1)

319 to 327
(13F to 147H)

R

Error log
block 11

(Same as error log block 1)

328 to 336
(148 to 150H)

R

Error log
block 12

(Same as error log block 1)

337 to 345
(151 to 159H)

R

Error log
block 13

(Same as error log block 1)

346 to 354
(15A to 162H)

R

Error log
block 14

(Same as error log block 1)

355 to 363
(163 to 16BH)

R

Error log
block 15

(Same as error log block 1)

364 to 372
(16C to 174H)

R

Error log
block 16

(Same as error log block 1)

373 to 375
(175 to 177H)

—

Error log
block 1

Error log area

Error log block
area

System area

Connection No.

Reference
section

0
(0H)

Section 11.4

0
(0H)

Section 11.4

Local station Port No.

—

—

—

—

—

—

(Continues on the next page)

3 - 15

3 - 15

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Name

376 to 377
(178 to 179H)

R

Received IP packet count

378 to 379
(17A to 17BH)

R

Received IP packet count discarded
due to sum check error

380 to 381
(17C to 17DH)

R

Sent IP packet total count

382 to 397
(17E to 18DH)

—

398 to 399
(18E to 18FH)

R

Simultaneous transmission error
detection count
(Receiving descripter deletion count)

400 to 407
(190 to 197H)

—

System area

408 to 409
(198 to 199H)

R

Received ICMP packet count

410 to 411
(19A to 19BH)

R

Received ICMP packet count
discarded due to sum check error

412 to 413
(19C to 19DH)

R

Sent ICMP packet total count

414 to 415
(19E to 19FH)

R

Echo request total count of received
ICMP packets

416 to 417
(1A0 to 1A1H)

R

Echo reply total count of sent ICMP
packets

418 to 419
(1A2 to 1A3H)

R

Echo request total count of sent ICMP
packets

420 to 421
(1A4 to 1A5H)

R

Echo reply total count of received
ICMP packets

422 to 439
(1A6 to 1B7H)

—

440 to 441
(1B8 to 1B9H)

R

Received TCP packet count

442 to 443
(1BA to 1BBH)

R

Received TCP packet count
discarded due to sum check error

444 to 445
(1BC to 1BDH)

R

Sent TCP packet total count

446 to 471
(1BE to 1D7H)

—

System area

472 to 473
(1D8 to 1D9H)

R

Received UDP packet count

474 to 475
(1DA to 1DBH)

R

Received UDP packet count
discarded due to sum check error

476 to 477
(1DC to 1DDH)

R

Sent UDP packet total count

478 to 481
(1DE to 1E1H)

—

System area

482 to 491
(1E2 to 1EBH)

—

492 to 493
(1EC to 1EDH)

R

494 to 495
(1EE to 1EFH)

R

496 to 497
(1F0 to 1F1H)

R

498 to 511
(1F2 to 1FFH)

—

3 - 16

IP

ICMP

Error log area

Status for each
protocol

System area

System area

TCP

UDP

System area

Initial value
Decimal
(Hexadecimal)

0
(0H)

—

—

—

Reference
section

Section 11.3

—
Section 11.5
POINT (3)

0
(0H)
—

0
(0H)

—

—

0
(0H)

––

—

––

0
(0H)

—

—

—

—
0
(0H)

Framing error count

0
(0H)

Receivi
Overflow count
ng error

0
(0H)

CRC error count
System area

Flash ROM
save

—

—

3 - 16

3

SPECIFICATIONS

MELSEC-F
(e) Router relay parameter setting area (BFM #512 to 1599)

BFM number
Decimal
(Hexadecimal)

Attribute

512 to 513
(200 to 201H)

R/W

514 to 515
(202 to 203H)

R/W

516 to 1599
(204 to 63FH)

—

3 - 17

Application

Name

Initial value
Decimal
(Hexadecimal)

Sub-net mask
Router relay
parameter
setting area

0
(0H)

Default router IP address
System area

Flash ROM
save

—

Reference
section

Section 5.3

—

—

3 - 17

3

SPECIFICATIONS

MELSEC-F
(f)

Open/close control (BFM #1600 to 1663)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Name

Initial value
Decimal
(Hexadecimal)

Flash ROM
save

Reference
section

Reinitialization

• Write value
Re-initialization request
0001H : Re-initialization ([COM.ERR.] LED OFF)
0002H : Re-initialization after reading data in Flash ROM
([COM.ERR.] LED OFF)
0005H : Re-initialization ([COM.ERR.] LED retains status.)
0006H : Re-initialization after reading data in Flash ROM
([COM.ERR.] LED retains status.)
• Read value
0008H : During re-initialization
8000H : At re-initialization completion
C000H : At re-initialization error
• In the re-initialization standby, the write value is read directly.

0
(0000H)

—

R/W

COM.ERR.
Off

[COM.ERR.] Off request
• Write value
0001H: [COM.ERR.] LED Off request
• Read value
0002H: Stores at normal completion
• 0001H is read while ready until LED OFF operation starts

0
(0000H)

—

1602
(642H)

R/W

Connection No.1 Open/Close command
• Write value
0001H: Open command
8000H: Close command
• Read value
b0=0 : Open command enabled
b0=1 : Open command disabled
0000H : Close status
(Including when FIN is sent from
the external device)
0003H : Open request or Listen being processed (b1, b0: ON)
Open/Close
0005H : Open status (b2, b0: ON)
For open/close command/status
0009H : Close request being processed
control
(b3, b0: ON)
0010H : Open error (Closed status) (b4: ON)
0015H : Open error (Open status) (b5: ON)
0001H : During open standby
8000H : During close standby

1603
(643H)

R/W

Connection No.2 Open/Close command

(Same as connection No.1)

1604
(644H)

R/W

Connection No.3 Open/Close command*1

(Same as connection No.1)

1605
(645H)

R/W

Connection No.4 Open/Close command*1

(Same as connection No.1)

1606 to 1609
(646 to 649H)

—

1600
(640H)

1601
(641H)

R/W

System area

0
(0000H)

—

Chapter 5

—

—

(Continues on the next page)
*1 Required only when MC protocol is set.

3 - 18

3 - 18

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Fixed buffer
communication
1610
(64AH)

Initial value
Decimal
(Hexadecimal)

Name

R/W

When sending request or reception complete
confirmation signal of connection No.1
• For sending
1) Write value
0001H : Sending request
2) Read value
0001H : Transmission ready
0002H : Between data being sent to while
waiting for a response (only when
procedure exists)
0004H : Stored when transmission
complete If instantly receiving the
next data, depending on the
timing of FROM instruction, 0001H
is stored without reading 0004H
0008H : Stored when transmission error
0000H : Stored when the open processing
or close processing is completed
• For receiving
1) Write value
Write value

For fixed buffer Transmission/
communication reception
request/Execution
result

0002H

Procedure

No procedure

Response
transmission
to an
external
device

Allows the
following data
to be received

Procedure

No procedure

Flash ROM
save

Reference
section

Chapter 6,
Chapter 7

0
(0000H)

2) Read value
Read value

1611
(64BH)

R/W

1612 to 1663
(64C to 67FH)

—

3 - 19

0001H

At data reception

0004H

Response
transmission
complete

0008H

Receiving process cannot be
normally completed

0000H

Stores after open/close
process

Acceptance
for the data
reception
complete

When sending request or reception complete
confirmation signal of connection No.2
System area

(Same as connection No.1)
—

—

—

3 - 19

3

SPECIFICATIONS

MELSEC-F
(g) Fixed buffer area (BFM #1664 to 9855)

BFM number
Decimal
(Hexadecimal)

Attribute

1664
(680H)

R/W

1665 to 2687
(681 to A7FH)

R/W

2688
(A80H)

R/W

2689 to 3711
(A81 to E7FH)

R/W

3712 to 9855
(E80 to 267FH)

—

3 - 20

Application

Name

Fixed buffer
No. 1
Fixed buffer
data area

Fixed buffer
No.2

System area

Initial value
Decimal
(Hexadecimal)

Data length
Fixed buffer data
Data length
Fixed buffer data
—

Flash ROM
save

Reference
section

0
(0H)

Chapter 6,
Chapter 7

0
(0H)

Chapter 6,
Chapter 7

—

—

3 - 20

3

SPECIFICATIONS

MELSEC-F
(h) Mail send parameter settings (BFM #9856 to 20479)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Name

9856 to 9887
(2680 to 269FH)

R/W

9888 to 9912
(26A0 to 26B8H)

—

9913 to 9920
(26B9 to 26C0 H)

R/W

Password to the POP3 server (16 characters)

9921
(26C1 H)

R/W

Method for designating SMTP server
0: Domain name designation
1: IP address designation (Decimal)
2: IP address designation (Hexadecimal)

9922 to 9953
(26C2 to 26E1 H)

R/W

9954
(26E2 H)

R/W

9955 to 9986
(26E3 to 2702 H)

R/W

9987 to10018
(2703 to 2722 H)

R/W

10019 to 10050
(2723 to 2742 H)

Initial value
Decimal
(Hexadecimal)

Local station mail address (Maximum of 64 characters)
System area

Flash ROM
save

"\0"
—

Reference
section

Chapter 10
—

Chapter 10

"\0"

Chapter 10

1

Chapter 10

0.0.0.0

Chapter 10

1

Chapter 10

0.0.0.0

Chapter 10

Send destination address 1

"\0"

Chapter 10

R/W

Send destination address 2

"\0"

Chapter 10

10051 to 10082
(2743 to 2762 H)

R/W

Send destination address 3

"\0"

Chapter 10

10083 to 10114
(2763 to 2782 H)

R/W

Send destination address 4

"\0"

Chapter 10

10115 to 10146
(2783 to 27A2 H)

R/W

Send destination address 5

"\0"

Chapter 10

10147 to 10178
(27A3 to 27C2 H)

R/W

Send destination address 6

"\0"

Chapter 10

10179 to 10210
(27C3 to 27E2 H)

R/W

Send destination address 7

"\0"

Chapter 10

10211 to 10242
(27E3 to 2802 H)

R/W

Send destination address 8

"\0"

Chapter 10

10243 to 10274
(2803 to 2822 H)

R/W

Send destination address 9

"\0"

Chapter 10

10275 to 10306
(2823 to 2842 H)

R/W

Send destination address 10

"\0"

Chapter 10

10307 to 10332
(2843 to 285C H)

—

Domain name of the SMTP server (maximum 64 characters)
or IP address*1
Method for designating POP3 server
0: Domain name designation
1: IP address designation (Decimal)
2: IP address designation (Hexadecimal)
Domain name of the POP3 server (maximum 64 characters)
or IP address*1
Shared area for
e-mail buffers

System area

—

—

Chapter 10

(Continues on the next page)

3 - 21

3 - 21

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Name

Reference
section

R/W

Mail sending
command

• Write value
Mail sending instruction (0001H)
• Read value
Returns to "0000H" when mail sending commences
Multiple requesting exists. (0002H)

0
(0000H)

Chapter 10

R

Mail sending
status

Initial status (0000H)
Mail sending normally completed (0001H)
Mail sending abnormally completed (0002H)
While mail being sent (8000H)

0
(0000H)

Chapter 10

10335
(285FH)

R

Error codes
when sending
e-mail

When sending mail to a single address, depending on the sending
instruction (BFM #10333: 0001H), the memory is cleared and the
first error code found is stored. When sending mail to multiple
addresses, the first error code found is stored, even after other
errors. "
The second error and later errors are not stored.

0
(0000H)

Chapter 10

10336
(2860H)

R

Sending result
of e-mail

0
(0000H)

Chapter 10

0
(0000H)

Chapter 10

0
(0000H)

Chapter 10

10333
(285DH)

10334
(285EH)

Send destination address 1

Success (b0: ON) / Failure (b0: OFF)
to
Send destination address 10 Success (b9: ON) / Failure (b9: OFF)
Turns on the bit of the mail address that sends an e-mail.

10337
(2861H)

R/W

Sending
designation
of e-mail

Sending destination address 1

Enable (b0: ON) / Disable (b0: OFF)
to

Sending destination address 10 Enable (b9: ON) / Disable (b9: OFF)
Initialized into 0000H by mail sending instruction, and the bit is
updated sequentially depending on the sending result.

R/W

Attached file
format

0000H: Sends the attached file in binary format (maximum 2048
words)
0001H: Sends the attached file in ASCII format (maximum 2048 words)
0002H: Sends the attached file in CSV format (maximum 2048 words)
0004H: Sends the attached file as a text mail (maximum 256 words)

10339 to 10402
(2863 to 28A2H)

R/W

Subject

Stores a subject (maximum 128 characters)

10403
(28A3H)

R/W

Word count of
attached file

Designates the word count of main text (0 to 256)/attached file (0
to 2048)

10404 to 12451
(28A4 to 30A3H)

R/W

Main text of
attached file

Stores a main text or an attached file

12452 to 20479
(30A4 to 4FFFH)

—

System area

10338
(2862H)

*1 (example)192. 168. 0. 10

3 - 22

"\0"

—

0
(0000H)

—

"\0"

—

—

C0

A8

00

0A

4)

3)

2)

1)

SMTP : BFM#9922
POP3 : BFM#9955

H

L

2)

1)

SMTP : BFM#9923
POP3 : BFM#9956

4)

3)

—

—

3 - 22

3

SPECIFICATIONS

MELSEC-F
(i)

Connection status storage area (BFM #20480 to 22639)

BFM number
Decimal
(Hexadecimal)

Attribute

20480
(5000H)

R

20481
(5001H)

—

Application

R

20483 to 20484
(5003 to 5004H)

—

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Open complete signal
0: Open incomplete
1: Open completed
• Connection No. 1 (b0)
• Connection No. 2 (b1)
• Connection No. 3 (b2)
• Connection No. 4 (b3)
TCP : 1 by connection establishment
UDP : 1 by communication enabled

Connection
status storage
area

20482
(5002H)

Name

System area
Connection
status
Open request signal
information area
0: No open request
1: Open being requested
• Connection No. 1 (b0)
• Connection No. 2 (b1)
• Connection No. 3 (b2)
• Connection No. 4 (b3)
TCP Passive : 1 by listen
Active : 1 by open process
UDP : 1 by communication enabled
System area

0
(0H)

—

Section 5.6

—

0
(0H)

—

Fixed buffer reception status signal
0: Data not received
1: Data being received
• Connection No. 1 (b0)
• Connection No. 2 (b1)

Reference
section

—

Section 5.6

—

—

20485
(5005H)

R

20486 to 20504
(5006 to 5018H)

—

20505 to 20506
(5019 to 501A H)

R/W

DNS server 1 IP address

0
(0H)

Section
10.6

20507 to 20508
(501B to 501C H)

R/W

DNS server 2 IP address

0
(0H)

Section
10.6

20509 to 20510
(501D to 501E H)

R/W

System port
DNS server 3 IP address
information area

0
(0H)

Section
10.6

20511 to 20512
(501F to 0520 H)

R/W

DNS server 4 IP address

0
(0H)

Section
10.6

20513 to 20591
(5021 to 506F H)

—

20592 to 20994
(5070 to 5202H)

—

20995
(5203H)

R/W

20996 to 22639
(5204 to 586F H)

—

3 - 23

Fixed buffer
information area

System area

—

System area
System area
"Interrupt
detection"
status storage
area
System area

0
(0H)

Chapter 7

—

—

—

—

—

—

—

—

0
(0H)

Interrupt detection count

—

—

—

—

3 - 23

3

SPECIFICATIONS

MELSEC-F
(j)

E-mail status storage area (BFM #22640 to 31999)

BFM number
Decimal
(Hexadecimal)

Attribute

Application

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Name

22640 to 23354
(5870 to 5B3AH)

—

System area

23355
(5B3BH)

R

Number of mails normally completed

23356
(5B3CH)

R

Attached files sent count

23357
(5B3DH)

R

Sent to the SMTP server count

23358
(5B3EH)

R

Number of mails abnormally completed

23359
(5B3FH)

R

Error log write count

23360
(5B40H)

R

Error log write pointer

23361
(5B41H)

R

Error code

23362
(5B42H)

R

Command code

23363 to 23370
(5B43 to 5B4AH)

R

23371 to 23374
(5B4B to 5B4EH)

R

23375 to 23404
(5B4F to 5B6CH)

R

23405 to 23448
(5B6D to 5B98H)

R

Error log block 2

(Same as error log block 1)

23449 to 23492
(5B99 to 5BC4H)

R

Error log block 3

(Same as error log block 1)

23493 to 23536
(5BC5 to 5BF0H)

R

Error log block 4

(Same as error log block 1)

23537 to 23580
(5BF1 to 5C1CH)

R

Error log block 5

(Same as error log block 1)

23581 to 23624
(5C1D to 5C48H)

R

Error log block 6

(Same as error log block 1)

23625 to 23668
(5C49 to 5C74H)

R

Error log block 7

(Same as error log block 1)

23669 to 23712
(5C75 to 5CA0H)

R

Error log block 8

(Same as error log block 1)

23713 to 24319
(5CA1 to 5EFFH)

—

E-mail status
storage area

Send

—

To

Error log block 1

—

Reference
section
—

0
(0H)

Section
11.4

0
(0H)

Section
11.4

Date *1
Subject

System area

—

—

—

(Continues on the next page)
*1 The timestamp for an email that had a communication error with the mail server is stored in BCD code in the following manner.

b15

to

b8

b15

to

b7

b8

b7

Hour (00 to 23H)
b15

to
to

b8

to

b0

b7

to

b0

Minutes (00 to 59H)
b8

Higher 2-digits of year (00 to 99H)

3 - 24

b0

Date (01 to 31H)

Second (00 to 59H)
b15

to

Lower 2-digits of year (00 to 99H)

Month (01 to 12H )

b7

to

b0

Day of the week (0 to 6)
SUN:0 to SAT:6

3 - 24

3

SPECIFICATIONS

MELSEC-F
(Continued from the previous page)

BFM number
Decimal
(Hexadecimal)
24320
(5F00H)

Attribute

Application

Name

Initial value
Flash ROM
Decimal
save
(Hexadecimal)

Reference
section

25
(19H)

Section
10.6

0
(0H)

Section
10.6

R/W

SMTP server port number

24321
(5F01H)

R/W

SMTP authentication setting
0: No authentication
1: SMTP-AUTH
2: POP before SMTP
Any other value is handled as "0".

24322, 24323
(5F02, 5F03H)

—

24324 to 24355
(5F04 to 5F23H)

R/W

SMTP login ID (64 characters)

"\0"

Section
10.6

24356 to 24387
(5F24 to 5F43H)

R/W

SMTP password (64 characters)

"\0"

Section
10.6

24388
(5F44H)

R/W

POP3 server port number

110
(6EH)

Section
10.6

24389 to 24575
(5F45 to 5FFFH)

—

24576 to 31799
(6000 to 7C37H)

—

31800
(7C38H)

Mail Function

System area

System area
System area

R/W

R/W

—

—

—

—

—

—

0
(0000H)

—

COM.ERR. Off

Designates the function to be cleared
0000H : [COM.ERR.] LED Off, error code clear
FFFFH: Error log clear

0
(0000H)

—

0
(0000H)

—

0
(0000H)

—

31802
(7C40H)

R/W

Executing error
clear

31803
(7C41H)

R/W

Result of
execution error
clear

Stores result of execution error clear
0000H: Normally executed
Other than 0000H: Error code

31804 to 31999
(7C42 to 7CFFH)

—

32000 to 32639
(7D00 to 7F7FH)

—

3 - 25

—

Error information to be
cleared

Executes error clear
• Write value
0001H: Executes error clear
• Write value
0002H: Stored at error clear
The result is stored in BFM#31803

System area
System area

—

Designates the error information to be cleared
: Clears initial error code (BFM#105)
0000H
0001 to 0004H : Clears the open error code of
connection 1 to 8 (BFM#124, 134,
144, 154, 164).
Each of the following connection
corresponds.
0001H: Connection 1
0002H: Connection 2
0003H: Connection 3
0004H: Connection 4
: Clears the error log block area
0100H
(BFM#227 to 372) to 0.
: Clears communication status (status
0101H
for each protocol) (BFM#376 to 511)
: Clears communication status (E-mail
0103H
receive status) (BFM#23353 to 23712)
FFFFH
: Clears all of the above

Error information
clear
31801
(7C39H)

—

—

—

—

—

—

—

3 - 25

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4 SETTINGS AND PROCEDURES PRIOR TO OPERATION
This chapter explains the settings and procedures required prior to operating the
Ethernet module in a system.

4.1 Loading and Installation
This section explains precautions for Ethernet module handling from unpacking to
installation, as well as the installation environment common to all modules.
For more details on module mounting and installation, refer to the Installation Manual
supplied with the Ethernet module.

4.1.1 Handling precautions

4

The following explains precautions for Ethernet module handling:
(1) Since it is made of resin, the Ethernet module case should not be dropped or
subjected to any shock.
(2) Tighten the module terminal and fixing screws within the following specified
clamping torque range:
Screw location
External power supply terminal screw (M3 screw)
Unit-affixing screw ( M4 screw )

DANGER

Tightening torque range
0.5 to 0.8 N•m
0.78 to 1.08 N•m

Do not touch the terminals and connectors while the power is on.
Doing so may result in electric shocks and malfunctions.
Make sure to turn off all phases of the external power supply before cleaning or
re-tightening the screws. Failure to do so may cause damages or malfunctions of
the module.
If the screws are loose, it may cause the module to short circuit, malfunction or
fall off.
Tightening the screws excessively may damage the screws and/or the module
and cause the module to short circuit, malfunction or fall off.
Do not write any data in the "System area" of the buffer memory on the module.

4-1

4-1

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

Be careful not to let any foreign matter such as wire chips get inside the module.
They may cause fire, as well as breakdowns and malfunctions of the module.

CAUTION

Never disassemble or modify the module.
This may cause breakdowns, malfunctions, injuries or fire.
When attaching or removing the base module and all expansion module special
blocks, make sure to cut all external power supplies.
Failure to do so may cause the module to breakdown or malfunction.
Tighten the terminal screws using the specified torque.
If the terminal screws are loose, it may cause the module to short-circuit,
malfunction or fall off.
Tightening the terminal screws excessively may damage the screws and/or the
module and cause the module to short-circuit, malfunction or fall off.
Do not directly touch the conducting parts and electronic parts of the module.
This may cause the module to malfunction or fail.

4

When disposing of this product, treat it as industrial waste.
A protective sheet is pasted on the upper part of the module in order to prevent
foreign matter such as wire chips to get inside the module while wiring.
Do not remove this protective sheet during wiring work.
However, be sure to remove the protective sheet before operating the module to
allow heat radiation during operation.
Before performing control operations (especially data modifications, program
modifications and operating-status modifications) on the PLC in operation, be
sure to confirm the safety.
For basic module status control (remote RUN/STOP and similar controls)
previous parameter settings should normally be set to open. If these conditions
are not met, after a remote STOP, the communication line is closed from another
node and cannot be re-opened, so remote RUN cannot start.

4.1.2 Installation environment
This section explains the installation environment for the PLC. When installing the
PLC, the following environments must be avoided:
•
•
•
•
•

Locations where the ambient temperature exceeds the range of 0 to 55 .
Locations where the ambient humidity exceeds the range of 5 to 95 % RH.
Locations where condensation occurs due to a sudden temperature change.
Locations where there are corrosive or flammable gases.
Locations exposed to considerable amounts of conductive powdery substances
such as dust and iron filing, oil mist, salt, or organic solvents.
• Locations exposed to direct sunlight.
• Locations exposed to strong electric or magnetic fields.
• Locations where vibrations or impacts are directly applied to the main unit.

CAUTION

4-2

Use the PLC in the operating environment that meets the general specifications
described in the user's manual of the PLC to use.
Using the PLC in any other operating environments may cause electric shocks,
fires or malfunctions, or may damage or degrade the module.
4-2

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.2 Settings and Procedures Prior to Starting the Operation
The following shows a flow of the procedure that is required prior to operating:
Procedures prior
to operation

Connect the Ethernet module to the base module and
wire the 24VDC power supply.

Connect the Ethernet module to the Ethernet network.

See Section 4.4, "Connecting
to the Network."

Setting the Ethernet module network parameters .

See Section 4.5, "Settings from
Ethernet Parameters."

Send the "Ping" command from an external device and
confirm the completion of the Ethernet module initial
processing

See Section 5.4, "Confirming the Completion
of the Initial Processing."

Create a program for each communication

See applicable
communication function

Operation

POINT
(1) When the parameter settings are added or modified using the
FX Configurator-EN-L, the settings differs depending on the connection
condition to the Ethernet module as shown below.
When directly connected to the PLC
After the parameter settings are added or modified, re-initialization
processing can be automatically performed.
When connected via Ethernet
The added or modified parameter settings are not reflected.
To operate the Ethernet module after the parameter settings are added or
modified with FX Configurator-EN-L, first save the parameter values,
second reboot the Ethernet's module power.
(2) Timing for powering ON
Power ON the PLC and the Ethernet module with the timing as shown below.
ON
PLC
Ethernet
module

ON

OFF
OFF

When turning the system power ON
Turn the power of the Ethernet module ON first, and then turn ON the
power of the PLC after that when different power source is used for the
PLC and Ethernet module.
It is possible to supply power to the Ethernet module from the 24 VDC
service power supply of the PLC. (Pay attention to the current capacity of
the service power supply of the PLC.)
When turning the system power OFF
Turn the power of the PLC and Ethernet module OFF at the same time.
Or turn OFF the power of the PLC first, and then turn OFF the power of the
Ethernet module after that.
4-3

4-3

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

Important
(1) Do not write any data in the "System area" of Ethernet module buffer memory.
(2) When status control (such as remote RUN/STOP) from a external device is
used for the PLC, the user should select "Always wait for OPEN" beforehand
using the setting parameters. (Select using initial timing in the operation
settings.)
If "Do not wait for OPEN" is selected, the communication line will be closed
during remote STOP. After that, communication cannot be reopened from the
PLC side and remote run from the external device will not work.
(3) When the Ethernet module is replaced, reset the parameters.
(4) When the Ethernet module is replaced, reboot the external device as well. (If
the external device retains the Ethernet address, it may be impossible to
continue communication because when a module is replaced the Ethernet
address changes.)
In the same way, when the external device (personal computer, etc.)is
replaced, reboot the Ethernet module.

4-4

4-4

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.3 Components of the Ethernet Module
This section shows the components of the Ethernet module.
4)

1)

3)

2)

View with the cover removed

Name

4-5

Description

1)

LED display

Refer to the contents of the LED displays (1).

2)

10BASE-T/100BASE-TX
connector (RJ45)

Connector for connecting the Ethernet module to the 10BASE-T/100BASE-TX.
(Ethernet module chooses between 10BASE-T and 100BASE-TX according to
the hub.)

3)

Extension cable

Cables to connect to the PLC

4)

External 24VDC terminal

Power supply terminal for 24VDC

4-5

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

(1) LED display contents (*1)

LED name

Display description

When the LED is on

When the LED is off

RUN

Normal operation display

Normal
(when FROM/TO instruction can
be executed from PLC side)

Abnormal
(when WDT is in operation)

INIT.

Initial processing status display

Normal completion

Not processed
(when execution failed initial
processing)

100M

Transmission speed display

100Mbps

10Mbps/When not connected

SD

Data sending display

Data being sent

Data not being sent

RD

Data receiving status display

Data being received

Data not being received

Setting abnormal display

Abnormal *2

Normal setting

ERR.
COM.ERR.

Communication abnormal display

Communication abnormal
occurrence *3

Normal communication in progress

POWER

Module power status

Power is on

C1 to C4

TCP/IP, UDP status of the
connections

TCP/IP : Connection Established TCP/IP : Connection not Established
UDP : Open
UDP : Closed

Power is off

*1 Refer to Subsection 11.1.1 for causes of error displays and the corresponding corrective
actions.
*2 The [ERR.] LED turns on in the following cases:
• When the parameter written is incorrect.
• When the checksum of the parameter written is not identical.
• When an error has occurred in the Ethernet module and operation is disabled due to the error.
*3 Refer to Subsection 11.1.1 for the status when the [COM.ERR.] LED is on.

4-6

4-6

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.4 Connecting to the Network
The following explains how to connect the Ethernet module to the 100BASE-TX/
10BASE-T networks.
Some precautions that should be observed while connecting the Ethernet module are
also shown below. Pay close attention to safety and use the Ethernet module
properly.
(1) Sufficient network knowledge and safety precautions are required when installing
100BASE-TX or 10BASE-T networks. Consult a specialist when connecting
cable terminals or installing trunk line cables, etc.
(2) Use a connection cable conforming to the standards shown in Section 2.2.

CAUTION

Do not bundle the control wires and the communication cables with the main
circuit and the power wires, and do not install them close to each other. They
should be installed at least 100 mm (3.94 in.) away from each other. Failure to do
so may generate noise that may cause malfunctions.
Make sure to place the communication and power cables to be connected to the
module in a duct or fasten them using a clamp.
If the cables are not placed in a duct or fastened with a clamp, their positions may
be unstable or moved, and they may be pulled inadvertently. This may damage
the module and the cables or cause the module to malfunction because of faulty
cable connections.

When disconnecting the communication and power cables from the module,
do not pull the cables by hand.
When disconnecting a cable with a connector, hold the connector to the
module by hand and pull it out to remove the cable.
When disconnecting a cable without a connector, loosen the screws on the
terminal block first before removing the cable.
If a cable is pulled while connected to the module, it may cause the module to
malfunction or damage the module and the cable.

POINT
Cautions regarding powering the hub, PLC and Ethernet module simultaneously.
On some hubs, for a fixed period of time immediately after powering up, even if
packets are sent from the Ethernet device, there are cases when packets are not
sent to the external device. For this case, create a sequence program that waits a
sufficient amount of time after powering up before sending packets.

4-7

4-7

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.4.1 Connecting to the 10BASE-T/100BASE-TX network
This section explains how to connect the Ethernet module to the 10BASE-T,
100BASE-TX network.
The following shows the connection diagram for the twisted paid cable.

RJ45 type modular
shielded twisted-pair cable
(Category 3, 5, 5e)

RJ45 type modular jack


(Step 1) Connect the twisted-pair cable to the hub.
(Step 2) Connect the twisted-pair cable to the Ethernet module.

POINT
(1) The Ethernet module detects whether it is 10BASE-T or 100BASE-TX, and in
full-duplex or half-duplex transmission mode automatically according to the
hub.
For connection to the hub without the auto detection function, set the halfduplex mode on the hub side.
(2) For 10BASE-T or 100BASE-TX connection required devices and a sample
system configuration, refer to Section 2.2 (1) and (2).

4-8

4-8

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.5 Ethernet Module Setting
Setting the Ethernet module as a network module.
The settings found must always be set in order to use the Ethernet module.

(1) "Operational settings" (Details are explained in Section 4.6)
This is for setting common items for when other modules use the Ethernet
module.
This settings must always be set, since they are required for the Ethernet initial
processing.

(2) "Initial settings" (Details are explained in Section 5.2)
This is for setting common timer values for TCP/IP communication to be used in
the Ethernet module as well as for setting the DNS server in order to use the email function.
It is not necessary to set the timer values when communicating using the initial
timer values.

(3) "Open settings" (Details are explained in Section 5.5)
This is for setting connection open processing, buffer memory for fixed buffer
communication and MC protocol to communicate data with an external device.

(4) "Router relay parameter (Routing information)" (Details are
explained in Section 5.3.)
The following setting for data communication with external devices are set:
• Communicating with external devices connected to other Ethernet networks
via a router

(5) "E-mail settings" (Details are explained in Section 10.6)
These settings are for using the e-mail transmission.
Ethernet parameter settings are written to buffer memory with a ladder program, and
the contents are stored in the Ethernet module's flash ROM.
Also, the contents can be set with FX Configurator-EN-L.

4-9

4-9

4

SETTINGS AND PROCEDURES PRIOR TO OPERATION

MELSEC-F

4.6 Operational Settings
This section explains how to set the operations parameters.
BFM number [Decimal]
(bit number)

Setting name

Setting description

Setting range/selection

Communication data code

24 (b1)

Select the communication data code.

OFF : Binary code
ON : ASCII code

TCP Existence confirmation setting

24 (b4)

Select the existence check method for TCP communication

ON : Use KeepAlive
OFF : Use Ping

Send frame setting

24 (b5)

Select the frame format to send

OFF : Ethernet (V2.0)
ON : IEEE 802.3

Initial Timing

24 (b8)

Perform the setting for opening

OFF : Do not wait for OPEN
ON : Always wait for OPEN

0 to 1

Set the IP address of the local station.

IP Address setting

IP Address

-

[BFM#24 initial processing parameter setting area]

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

(1) Communication data code setting
(2) TCP Existence confirmation setting

(3) Send frame setting

(4) Initial timing setting

(1) Communication data code (BFM#24 b1)
(a) Select the format of the communication data when communicating with an
external device.
Name of setting

Description of setting

Binary code

Communicate using binary data.

ASCII code

Communicate using ASCII data.

(b) For more details on the data communication codes, see Section 3.2, "Data
Codes for Communication."

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(2) TCP Existence confirmation setting (BFM #24 b4)
Select the existence check method for TCP communication.
For the existence check function, refer to Subsection 5.2.2.
Name of setting

Description of setting

Use the KeepAlive

Checks connection status with KeepAlive.

Use the Ping

Checks connection status with Ping.

POINT
(1) "Operational settings" parameters must always be set.
If the settings are changed, the power to the PLC and the Ethernet module
must be turned off once and then turned on again.
(2) If re-initialization of the Ethernet module is required due to the occurrence of
an error, perform re-initialization using a sequence program.

NOTE
When adjusting settings with FX Configurator-EN-L, select "Operating Settings" at
the initial screen and adjust the settings at the "Ethernet Operating Settings" screen.

(3) Send frame setting (BFM #24 b5)
(a) Select the frame of the Ethernet header for the data link layer to be sent by
the Ethernet module.
Setting item

Description of setting

Ethernet (V2.0)

Transmits using an Ethernet frame.

IEEE802.3

Transmits using an IEEE802.3 frame.

(b) When receiving data from the external device, reception should occur
regardless of whether the Ethernet frame or IEEE802.3 frame is used

NOTE
(1) Transmission using Ethernet frames is generally recommended.
(2) When communication with the external device fails, check whether or not
communication is possible using a PING command.

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(4) Initial Timing (BFM#24 b8)
(a) Select the timing to open connections for which TCP-Passive open or UDP
open are selected with the "Open settings" parameter (*1).
*1 For more details on the open settings, see Section 5.5 "Open Settings".
Name of setting
Do not wait for OPEN
(Communication
impossible after STOP)
Always wait for OPEN
(Communication possible
after STOP)

Description of setting
• Execute open/close processing using a sequence program.
• Communication cannot be performed while the PLC is in the STOP status.
• Passive open and UDP open connections always wait for open according to the parameter settings (a sequence program for open/close processing is not required) (*2).
• Communication can be performed while the PLC is in the STOP status.

*2 If the sequence program of the local station's PLC executes the close processing, the station is not placed
in the OPEN request wait status after the connection is shut off.

(b) In the following cases, open/close processing is required with instructions
written to the buffer memory (BFM #1602 to 1605).
• When "Do not wait for OPEN" is selected in the initial timing settings.
• If the "Open settings" are not performed for a connection.
• If "TCP-Active" is selected in the "Open settings" for a connection.
For detail on the open/close processing, see Section 5.6 "Open Processing/
Close Processing of the Connection".

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(5) IP Address settings - IP address (BFM #0 to 1)
(a) Set the IP address of the local station according to the specified input format
(decimal or hexadecimal).
It should be set so that the local station Ethernet module and the
communicating external device have the same class and sub-net address
(two words).
[IP address]
BFM #1

BFM #0

Values bits 7 to 0
to
Values bits 31 to 24

(Example) Program for "192.168.1.254 (C0 A8 01 FEH)"

DMOV

H0C0A801FE

U \G0

MOV

H9872

U \G25

IP adress "192.168.1.254
(C0 A8 01 FEH)" is stored
in BFM #0, #1
Write command for configuration
data to a flash ROM.

corresponds to the module number.

(b) It is necessary to use the router relay function in order to communicate with
an external device on another Ethernet network (different sub-net address).
For more details, see Section 5.3, "Router Relay Parameter".
(c) Set the IP address after consulting a network administrator (the person who
plans the network and manages IP addresses).

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4.7 Self-Diagnostic Tests
This section explains the self-diagnostic tests for checking the hardware and
transmission and reception function of the Ethernet module.

4.7.1 Self loopback test
The following explains the self loopback test that is used to check the hardware
including the Ethernet module's transmission and reception circuit.
The self loopback test transmits a test message within the Ethernet module to check if
the same message can be received or not. (Connection to the hub is not necessary.)
The following explains the procedure for performing the self loopback test. The test
takes approximately five seconds to complete.
The test result can be judged from the LED displays on the front of the Ethernet
module.
Step

Status of LED

Description of operation

[RUN]

[C1]

[ERR.]

1

Perform a self loopback test in operation mode
( "0002H" is written to BFM #202).

—

—

—

2

The contents of BFM#202 are written to the flash ROM
("9872H" is written to BFM#25).

—

—

—

3

• Turn off the PLC and the Ethernet module.
• Set the RUN/STOP switch to the STOP side
• Reboot the PLC's and the Ethernet module's power.

—

—

—

4

The test is in execution.

5

The test results are shown on the LED after
approximately 5 seconds.

6

Turn off the PLC and the Ethernet module.

—

—

—

Normal
Error

: Lit

: Off

The following are probable causes of errors.
• Ethernet module hardware error
• Ethernet line error
An error code is stored in the error log area (BFM#229) in the buffer memory of the
Ethernet module; the error content can then be checked from GX Developer. (See
Sections 11.2 and 11.3.)

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4.7.2 Hardware test (H/W Test)
This section explains the RAM and ROM tests for the Ethernet module. The
procedure for the hardware test is as shown in the table below.
The test results are judged from the LED displays on the front of the Ethernet module.
Step

Status of LED

Description of operation

[RUN]

[C1]

[ERR.]

1

Perform a hardware test in operation mode.
("0003H" is written to BFM #202)

—

—

—

2

The contents of BFM#202 are written to the flash ROM
("9872H" is written to BFM#25)

—

—

—

3

• Turn off the PLC and the Ethernet module.
• Set the RUN/STOP switch to the STOP side.
• Reboot the PLC's and the Ethernet module's power.

—

—

—

4

The test is in execution.

5

The test results are shown on the LED after
approximately 5 seconds.

6

Turn off the PLC and the Ethernet module.

—

—

—

Normal
Error

: Lit

: Off

The following are probable causes of errors.
• Ethernet module RAM/ROM error
An error code is stored in the error log area (BFM #229) in the buffer memory of the
Ethernet module; the error content can then be checked from GX Developer. (See
Sections 11.2 and 11.3.)

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4.8 Maintenance and Inspection
This section explains the maintenance and inspection as well as the installing and
uninstalling of the Ethernet module.

4.8.1 Maintenance and inspection
The Ethernet module does not need to be inspected for anything particular other than
checking whether or not the connections of cables and the terminal screws are loose.
Maintain and inspect the system according to the same inspection items as described
in the user's manual for the PLC in order to use it in optimal operating conditions.

DANGER

Do not touch the terminals and connectors while the power is on.
Doing so may cause in electric shocks and malfunctions.
Make sure to turn off all phases of the external power supply before cleaning
or re-tightening the screws. Failure to do so may cause damages or
malfunctions of the module.
If the screws are loose, it may cause the module to short-circuit, malfunction
or fall off.
Tightening the screws excessively may damage the screws and/or the
module and cause the module to short circuit, malfunction or fall off.

CAUTION

Be careful not to let any foreign matter such as wire chips get inside the module.
They may cause fire, as well as breakdowns and malfunctions of the module.
Never disassemble or modify the module.
This may cause breakdowns, malfunctions, injuries or fire.

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4.8.2 Installing and uninstalling the module
Before installing or uninstalling the Ethernet module, make sure to read Section 4.1,
"Handling Precautions" thoroughly, ensure the safety of the installation, and handle
the module properly according to the instructions.
The following explains the procedures when installing/uninstalling the Ethernet
module.
 (*1)
(Step 1) Read and save the parameters from the Ethernet module using
FX Configurator-EN-L (*2)
(Step 2) Turn off the power supply to the base module, the extension device, and
the Ethernet module.
(Step 3) Remove the network cable and Ethernet module.
(Step 4) Set up and start up the new Ethernet module according to Section 4.2,
"Settings and Procedures Prior to Starting the Operation." (*3)
(Step 5) Reset the external device. (*4)
*1

*2

*3
*4

It is recommended to record and save parameters not only when the Ethernet
module is replaced but also when parameters for the Ethernet module are
created or modified.
When FX Configurator-EN-L is not installed :
1) Monitor the buffer memory in the Ethernet module using GX Developer, and
record set values of the parameters for the Ethernet module.
For details on the parameters, refer to Section 4.6 "Operational Settings",
Section 5.2 "Initial Processing", Section 5.3 "Router Relay Parameter" and
Section 5.5 "Open Settings".
2) After replacing Ethernet module, write the setting value into BFM by
GX Developer.
3) Write the setting value into the Flash ROM by BFM#25.
When the Ethernet module is replaced, use the FX Configurator-EN-L to reset
the parameters.
When the Ethernet module is replaced, reset the external device as well. (If the
external device retains the Ethernet address, it may be impossible to continue
communication because when a module is replaced the Ethernet address
changes.)
In the same way, when the external device (personal computer, etc.)is replaced,
restart the Ethernet module.


(Step 1) Turn off the power supply to the FX base module and the Ethernet
module.
(Step 2) Replace the FX base module. (See the Manual of FX base module.)
(Step 3) Turn on the power.

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5 COMMUNICATION PROCEDURE
This chapter gives an overview of the communication procedure using the Ethernet
module, as well as the required initial processing of the Ethernet prior to data
communication and the open processing for communication with an external device.
The sequence program can be effectively simplified by setting the parameters of the
Ethernet module supported by FX Configurator-EN-L.

5.1 Overview of the Communication Procedure
This section gives an overview of the procedure for performing data communication
with external devices via the Ethernet module.
• Start data communication by establishing connections with external devices via the
initial or open processing.
• End data communication by closing the connection, and, as a result, terminating all
communication processing.
The following diagram illustrates the communication procedure:
(There is no connection since UDP/IP does not have a notion of connection.)
Set parameters for the
Ethernet module using sequence
program or FX Configurator-EN-L

5

See Section 4.6, "Operational Settings."
See Section 5.2, "Initial Processing.
See Section 5.3, "Router Relay Parameter."
See Section 5.5, "Open Settings."

Start the PLC and Ethernet
module

Ethernet module initial processing

Open processing

Communication
using
the MC
protocol

5-1

See
Section
5.6.

Communication
using
fixed
buffers

Close processing

Automatically processed.

E-mail
sending

MELSOFT
connection

See
Section
5.6.

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NOTE
The following communication can be performed with an open device on other end.
• Communication using MC protocol
• Sending/receiving in fixed buffer communication (procedure exists)
When receiving communication request data from an external device

PLC

Ethernet module
(Subheader code)

60 H
Request from an external
device (receive)
Header

Response to the request (send)

80 to 85 H
93 to 96 H

Header
Ethernet

Data

00 to 05 H
13 to 16 H

IP

Device memory, etc.

Head

TCP

Communication using
the MC protocol
(read/write)

Sub header

5

Confirm the
request contents
with the
subheader.

Ethernet

OS

Application
data

E0 H

Sub header

* For receiving when the
communication is open

IP

Receive data normal
completion BFM operation

Fixed buffer communication
(Procedure exists)
(communication)

TCP

Receive data acquisition
processing

Store data
received

Application
data

Receive completion signal

Head

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5.2 Initial Processing
This section explains the initial processing of the Ethernet module.

5.2.1 Initial processing
The initial processing enables data communication with an external device by setting
the parameters required for data communication via the Ethernet module.
Set the following parameters in the sequence program, write them to the Ethernet
module; the initial processing of the Ethernet module is then performed by one of the
following methods.
• Re- initialization request (Write the re-initialization request (0001H, 0002H, 0005H or
0006H) to BFM #1600.)
• Power ON the Ethernet module again.

(1) Parameters required for initial processing
• "Operational settings"
• "Initial settings"

:(See Section 4.6.)
:(See Subsection 5.2.2.)

(2) Confirmation of initial processing result
Ethernet module
Initial processing

INIT.LED

Initial normal completion
signal (BFM#28 b0)

Initial abnormal completion
signal (BFM#28 b5)

Initial normal completion
signal (BFM#27)

At normal
completion

: On

ON

OFF

0001H

At abnormal
completion

: Off

OFF

ON

0000H

If the initial processing does not complete normally, correct the above parameter
setting value and write to the Ethernet module. Then re-initialize the Ethernet
module.

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5.2.2 Initial settings
This section explains the initial settings.

Timer
setting

Setting item name

BFM number
[Decimal]

Description of setting

Setting range/options

TCP ULP timer

4

Set the time of packet existence at TCP data transmission.

TCP zero window timer

5

Set the interval for checking the reception enabled status.

2 to 32767
2 to 32767

TCP resend timer

6

Set the time to resend at TCP data transmission.

2 to 32767

TCP end timer

7

Set the confirmation wait time at TCP close processing.

2 to 32767

IP assembly timer

8

Set the wait time for division data packets.

1 to 32766

Response monitoring timer

9

Set the response wait time.

2 to 32767

Destination existence
confirmation starting interval

10

Set the time to start confirming existence of an external device after
communication with it has terminated.

1 to 32767

Destination existence
confirmation interval timer

11

Set the time interval between reconfirming existence.

1 to 32767

Destination existence
confirmation resend timer

12

Set the number of times to reconfirm existence when a response to
the existence confirmation is not received.

1 to 32767

IP address of DNS server 1

20505 to 20506 Set IP address of DNS server 1.

—

DNS setting

IP address of DNS server 2

20507 to 20508 Set IP address of DNS server 2.

—

(*1)

IP address of DNS server 3

20509 to 20510 Set IP address of DNS server 3.

—

IP address of DNS server 4

20511 to 20512 Set IP address of DNS server 4.

—

*1 Details are explained in Section 10.6.

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(1) Timer setting - TCP ULP timer (BFM#4)
(a) This item sets the time of packet existence during TCP data sending.
This timer is passed through the parameter when TCP opens or data is sent.
(b) Set the value in the range from 2 to 32767.
(c) Timer setting = setting value

500 ms

(2) Timer setting - TCP zero window timer (BFM#5)
(a) The window indicates the reception buffer on the receiving side.
(b) When there is no more space in the receiving buffer (window size = 0) on the
receiving side, data communication has to wait until enough space is made.
When this occurs, the sending side sends a sending window confirmation
packet to the receiving side after the TCP zero window timer value has been
reached, and confirms the reception enabled status.
(c) Set the value in the range from 2 to 32767.
(d) Timer setting = setting value

500 ms

(3) Timer setting - TCP resend timer (BFM#6)
(a) Set the resend time if ACK is not returned during TCP opening or data
transmission. This timer is also used for the existence time of the ARP
function.
(ARP is resent in "TCP resend timer" value/2 if a response is not returned
after the sent ARP request.)
(b) Set the value in the range from 2 to 32767.
(c) Timer setting = setting value

500 ms

(4) Timer setting - TCP end timer (BFM#7)
(a) When the TCP connection is closed from the local station, this timer sets the
monitoring time for how long the local station waits for a FIN request from an
external device after it sends a FIN request and the external device returns
an ACK.
(b) If the FIN request cannot be received from the external device before the
time designated by the TCP end timer setting, a RST should be sent to the
external device to forcibly close the connection.
(c) Set the value in the range from 2 to 32767.
(d) Timer setting = setting value

5-5

500 ms

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(5) Timer setting - IP assembly timer (BFM#8)
(a) Communication data may be divided on the IP level due to the buffer
restriction at the sending or receiving station.
(b) Set the value in the range from 1 to 32766.
(c) Timer setting = setting value

500 ms

(6) Timer setting - Response monitoring timer (BFM#9)
(a) This timer setting sets the following times.
1) The time to wait for a response after sending a command.
2) The time to wait for the last message after receiving the first message
when the message is divided.
(b) Set the value in the range from 2 to 32767.
(c) Timer setting = setting value

500 ms

(7) Timer setting - Destination existence confirmation starting interval
(BFM#10)
(a) This timer sets the time interval before attempting to confirm the existence of
an external side when an open connection for which existence confirmation
is required does not respond.
(b) Set the value in the range from 1 to 32767.
(c) Timer setting = setting value

500 ms

(8) Timer setting - Destination existence confirmation interval timer
(BFM#11)
(a) This timer sets the time interval before reconfirming the existence of an
external device on an open connection for which existence confirmation is
required that does not respond.
(b) Set the value in the range from 1 to 32767.
(c) Timer setting = setting value

500 ms

(9) Timer setting - Destination existence confirmation resend timer
(BFM#12)
(a) This timer sets the number of times to reconfirm existence when there is no
response from an external device on an open connection for which existence
confirmation is required.
(b) Set the value in the range from 1 to 32767.

(10)DNS setting - IP address of DNS server n (*1)
*1

5-6

The DNS setting is set when the e-mail sending function is used.
Refer to Chapter 10, "E-mail Function".

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POINT
To adjust settings with FX Configurator-EN-L, select "Initial Settings" from the
initial screen, and make the settings at the "Ethernet Initial Settings" screen.

NOTE
(1) Set the value of each timer on the Ethernet module side such that the following
relations are met.
•

Response monitoring
timer value

•

TCP resend
timer value

TCP ULP
timer value

TCP end
timer value

TCP resend
timer value

IP assembly
timer value

TCP zero window
timer value

Furthermore, when connecting a line using Mitsubishi products, you should make
sure that both nodes have the same settings.
(2) Set the value of each timer on the external device side such way that the
following relations are met.
Communication errors such as transmission timeouts may occur more frequently
if the timer values are not set so that they satisfy the following relationships.
•
•

TCP resend timer value on
the external device side
Monitoring timer value for the
external device application software

TCP resend timer value on
the external device side
TCP ULP timer value on
the Ethernet module side

n *1

*1 n is the number of TCP segment transmissions and can be obtained via the following calculation:
n

Size of the message transmitted by the Ethernet module
Maximum segment size

(fractions below decimal
point are rounded up)

Example1: Number of TCP segment transmissions when communicating via the
same line
The maximum segment size is 1460 bytes via the same line (without
going through a router) and the number of TCP segment
transmissions is as follows:
• n = 1, if the size of the message transmitted by the Ethernet module
is 1460 bytes or less.
• n = 2, if the size of the message transmitted by the Ethernet module
is greater than 1460 bytes.
Example2: Number of TCP segment transmissions when communicating via
separate lines
The maximum segment size is at least 536 bytes on a separate line
(via router, etc.) and the number of TCP segment transmissions is as
follows:
• n = 1, if the size of the message transmitted by the Ethernet module
is 536 bytes or less.
• n = 2, if the size of the message transmitted by the Ethernet module
is greater than 536 bytes and no more than 1072 bytes.
• n = 3, if the size of the message transmitted by the Ethernet module
is greater than 1072 bytes and no more than 1608 bytes.

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(3) When communication errors occur, the setting value should be changed to
increase the number of retries.
The number of retries is obtained by using the following equation:
(In case of the initial values, 2 = (60/20) - 1)
•

TCP ULP timer value
TCP resend timer value

Number
of retries

-1

Example: Assuming the values are set in such a way that the number of retries is
two, a data transmission error will occur at the timing shown in the
figure below if data transmission fails (when communicating using fixed
buffer).
Transmission request
and status
#1610, #1611

W
0001H

R
0008H

R
0002H

Ethernet module
Data
command

First retry

A

TCP ULP
=
timer value

Second retry

A

A

TCP ULP timeout
value
TCP end
TCP resend
=
timer value
timer value

value
should
A(Each
: TCPtimer
resend
timer
valuebe identical.)
(The time after which the data should be retransmitted when
an "ACK" is not returned after sending data.)

(4) Perform the following setting in order to eliminate the retries explained in (3) (i.e.,
to set the number of retries to 0).
•

TCP ULP
=
timer value

TCP end
timer value

=

TCP resend
timer value

(Each timer value should be identical.)

(5) The target existence check is a function whereby the Ethernet module checks
whether or not a remote device is functioning normally by sending an existence
check message and then waiting to see whether a response message is
received. It is used if a connection to a remote device is open but communication
with the remote device has not been performed for a certain period of time.
(a) The existence check function has two methods of checking: PING and
KeepAlive.
The Ethernet module performs each of the existence checks based on the
setting values explained in (7) to (9) of this section and the existence check
setting of the open settings (refer to Section 5.5 (6)).
The existence check function (Ping or KeepAlive) can be selected at the time
of operation setting or re-initialization.
For the operation setting, refer to Section 4.6.
Refer to Subsection 5.2.3 for the explanation on re-initialization.

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1) Checking by KeepAlive
This method is used for a connection opened via the TCP/IP protocol.
The Ethernet module performs an existence check by sending an
existence check ACK message to a remote device with which
communication has not been performed for a certain period of time and
waiting to see whether or not a response is received. (*1)
*1 The connection is cut off if the remote device does not support the
TCP KeepAlive function (response to KeepAlive ACK messages).
2) Checking by PING
This method is used for a connection opened via the TCP/IP or UDP/IP
protocol.
The Ethernet module performs an existence check by sending a PING
command (using the ICMP echo request/response function) to a remote
device with which communication has not been performed for a certain
period of time and waiting to see whether or not a response is received.
(*2)

*2

Note that the Ethernet module automatically returns an echo
response packet when it receives a PING echo request command.
(It sends a response to the received PING command even if the
connection used in the data communication with the remote device
is closed.)

(b) The following actions are taken if a response message cannot be received
(an error is detected) from the remote device.
• The corresponding connection will be forcibly closed (the line is
disconnected). (*3)
*3 It is possible to reopen it with a user program.
• The open completion signal (the corresponding bit of BFM#20480) is
turned off and, the error code (C035H) is stored in places such as the open
error code storage area.
Also, the open/close status (BFM #1602 to 1605) value becomes "0000H".
Example: Assuming the values are set under the condition that the number of
retries is three, the Ethernet module performs target existence check at
the timing shown in the figure below.
(An example of existence check by PING)
Open completion signal
BFM#20480

Ethernet module
Last
communication
Target
existence
check starting
interval timer
value

5-9

PING
command

PING
PING
command
command
(Retransmitted) (Retransmitted)

Target
existence
check interval
timer value

Target
existence
check interval
timer value

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5.2.3 Re-initialization
Re-initialization is performed in order to place the Ethernet module into its startup
status without actually restarting the PLC.
Re-initialization of the Ethernet module can be performed in a sequence program.
The purposes of and how to program the re-initialization of the Ethernet module are
explained below.

NOTE
When FX Configurator-EN-L is being used, re-initialization can be performed after
downloading the parameters.
However, if it is connected to the Ethernet module via Ethernet, re-initialization
cannot be performed.
Re-initialize from the sequence program.

(1) Purposes of performing re-initialization
(a) To update address information of an external device maintained by the
Ethernet module
The Ethernet module maintains the IP address of the external device with
which it has been communicating and the corresponding Ethernet address
(MAC address). This is done in order to prevent other devices from
accessing the PLC illegally using the IP address of an external device with
which communication was performed normally. (*1)
For this reason it is necessary to re-initialize in order to clear the address
information of the external device maintained by the Ethernet module in case
a module or board on the external device side has been replaced due to
failure.
*1 Ethernet address is unique to a device. No devices share the same
Ethernet address.
(b) To change the IP address of the Ethernet module of the local station
If the system is changed, it is possible to restart communication with external
devices by changing the IP address (for the Ethernet module of the local
station) in the operation settings (see Section 4.6).
(c) To change the communication condition setting values
It is possible to restart communication with external devices by changing the
communication conditions in the operation settings (see Section 4.6).

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COMMUNICATION PROCEDURE

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(2) Programming and timing for re-initialization
The programming and timing for re-initialization is shown below:
• Program example for the unit No. 1
<>
Instruction

M1
M0

M0
=

U1\
G27

H0001

=

U1\
G1600

H8000

=

U1\
G1600

MOVP

Open completion signal
BFM#20480

HC000

Upon completion of Ethernet
module initial processing,
re-initialization is performed
Self-holding cancel

Processing upon normal
completion

Processing upon normal completion

Processing upon abnormal
completion

Abnormal end
BFM #27 is set to "0000H"
at abnormal end.

Re-initialization
(Normal)

1)

(Abnormal)

2)

Re-initialization request
TO BFM#1600

Re-initialization status
FROM BFM#1600

U1\
G1600

M1

Close processing
Initial Processing normal completion signal
BFM#27=0000H/0001H

H0001

Re-initialization request self-holding

3) 0001H

0000H

0002H

4) 8000H(Normal completion)/
C000H(Abnormal completion)

Module initialization

1) It is confirmed whether the initial processing has been completed
normally.
2) All data communication currently being performed with external devices
is terminated, and close processing will be performed on all connections.
3) "0001H ", "0002H ", "0005H " or "0006H " is written to BFM#1600.
(Initial normal completion signal: BFM#27 "0001H ")
(Open completion signal: BFM#20480 "All OFF(0H)")
4) When re-initialization is completed, the value in BFM#1600 will be 8000H
(normal completion) or C000H (abnormal completion).
* If the re-initialization is completed abnormally, the error code is stored
in the following area.
Initial error code storage area (BFM#105)

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(3) Operation for re-initialization
Operation for re-initialization differs as follows, depending on the value written to
BFM#1600.
Operation

Written value

COM. ERR LED

0001H

Turns off

0002H
0005H

No change

0006H

Re-reading flash ROM*1
Not re-read
Re-read
Not re-read
Re-read

*1: When re-reading the flash ROM, the re-initialization is performed in the same status as
when the power supply is turned on.

POINT
Please keep the following points in mind when re-initializing the Ethernet module.
(Failure to do so may cause errors in the data communication with the external
devices.)
(1) Be sure to end all current data communication with external devices and
close all connections before re-initializing.
(2) Be sure to reset external devices if the IP address of the Ethernet module has
been changed. (If an external device maintains the Ethernet address of a
device with which it communicates, the communication may not work after the
IP address of the Ethernet module has been changed.)

NOTE
It is possible to change the operational settings when re-initializing by a sequence
program.
Parameter setting item
Operational settings
Initial
settings

BFM number [decimal]

Parameter changes

Reference section

24

Section 4.6

Timer setting

4 to 12

Section 5.2

DNS settings

—

Section 5.2

32 to 39

Section 5.5

512 to 515

Section 5.3

Open settings
Router relay parameter
settings
E-mail settings
Send mail address
setting

9856 to 10306
9987 to 10306

Chapter 10

: Valid,

5 - 12

: Invalid

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5.3 Router Relay Parameter
This section explains the router relay parameter.
Setting item name

BFM number [Decimal]

Description of setting

Setting range/options

2
(b4, b5)

00 : Use
Select whether the router relay function is not used or is used.
01 : Not used

Sub-net mask pattern

512, 513

Set the sub-net mask.

C0000000 to FFFFFFFCH

Router IP address

514, 515

Set the IP address of the router to be routed through.

Other than 00000000H and FFFFFFFFH

Router relay function

NOTE
When making settings with the FX Configurator-EN-L, select [Router Relay
Parameters] from the initial screen and adjust the settings at the [Ethernet Router
Relay Parameter Settings] screen.

(1) Router relay function (BFM#2 b4,b5)
(a) Set whether the router relay function will be used or not.
The router relay function is not needed when communicating with the target
device on the same Ethernet network (the subnet address of the IP address
is the same).
(b) The router relay function allows communication with devices on other
Ethernet networks via routers and gateways.
(The router relay function does not mean a function to act as a router.)
(c) One router can be set for the router relay function.

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(2) Subnet mask pattern (BFM#512, 513)
(a) Set the subnet mask. *1 (Setting range: C0000000 to FFFFFFFCH)
Consult the network administrator for the setting.
(b) When not using the subnet mask, set any of the following table values
according to the class.
Class

*1

Mask value

Class A

FF000000H

Class B

FFFF0000H

Class C

FFFFFF00H

Ethernet networks include small-scaled network systems where multiple
devices are connected to one Ethernet hub along with medium and largescaled network systems where multiple small-scaled networks are
connected by routers, etc.
The subnet mask logically divides one network, where many devices are
connected, into multiple sub-networks to facilitate administration.

(Example) Class B

Network address
81H

05H

2FH

01H

IP address 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0 1 0 0 1 0 1 1 1 1 0 0 0 0 0 0 0 1
FFH

FFH

FCH

00H

Subnet mask 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
Subnet address
81H

05H

Host address
2FH

01H

IP address 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0 1 0 0 1 0 1 1 1 1 0 0 0 0 0 0 0 1

POINT
(1) All devices on the same sub-network must have a common subnet mask.
(2) When not administrated by the sub-network, the connected devices need not
have a subnet mask. (Set the network address of the corresponding class.)

(3) Router IP address (BFM#514, 515)
Set the IP address of the router to be used when FX3U-ENET-L communicates
with the target device on another Ethernet network (refer to (4) below).
Set the value that satisfies the following conditions.
• Condition 1: The IP address class is either A, B or C.
• Condition 2: The sub-net address of the default router is the same as that of
the local station Ethernet module.
• Condition 3: The host address bits are not all "0" or all "1".

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5.4 Confirming the Completion of the Initial Processing
The initial processing for the Ethernet module completes by selecting re-initialization,
then turning the power ON again, or re-initializing via buffer memory operations after
parameters are written to the Ethernet module.
(When the processing is completed normally, the [INIT.] LED on the front of the
Ethernet module turns on.)
• "Operational settings" parameter
• "Initial settings" parameter
This section explains how to check the completion of the initial processing.

POINT
The status of the Ethernet module becomes communication enabled when the
initial processing is completed normally. See reference sections for each
communication function to perform communication.
When the initial processing has not been completed normally, do the following to
check the error contents, take corrective actions, then execute the initial
processing again.
• Check the error code using the "Parameter status" of the Ethernet diagnostics.
(See Section 11.2.)
• Check the contents of the error corresponding to the error code, then take
corrective actions. (See Section 11.3 and Section 11.4.)

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COMMUNICATION PROCEDURE

5.4.1 PING command (Personal computer

MELSEC-F
Ethernet module)

The following example illustrates how to confirm the completion of the initial
processing by issuing the PING command to the local station's Ethernet module from
an external device connected on the same Ethernet network. (In the example, the
confirmation is made between devices whose IP address class and sub-net address
are identical.)

ping IP address

IP address of the Ethernet module: 192.0.1.254
Example of screen at normal completion
C:\>ping 192.0.1.254

Execute the ping command

Pinging 192.0.1.254 with 32 bytes of data:
Reply from 192.0.1.254: bytes=32 time=1ms TTL=128
Reply from 192.0.1.254: bytes=32 time<10ms TTL=128
Reply from 192.0.1.254: bytes=32 time<10ms TTL=128
Reply from 192.0.1.254: bytes=32 time<10ms TTL=128
Ping statistics for 192.0.1.254:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss)
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 1ms, Average = 0ms
C:\>_
Example of screen at abnormal completion
C:\>ping 192.0.1.254

Execute the ping command

Pinging 192.0.1.254 with 32 bytes of data:
Request timed out:
Request timed out:
Request timed out:
Request timed out:
Ping statistics for 192.0.1.254:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss)
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
C:\>_


Check the following items and send the PING command again.
• Check the Ethernet module's attachment.
• Check the connection to the Ethernet network.
• Check the contents of each parameter written to the Ethernet module.
• Check the operation condition of the Ethernet module (are there any
irregularities?).
• Check the IP address of the Ethernet module dictated by the PING command.
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5.4.2 Loop back test (Communication using MC protocol)
The loop back test can be performed with communication using MC protocol in order
to check the completion status of the initial processing for the target Ethernet module.
The following is an overview of the loop back test for communication using MC
protocol. See Chapter 9 for details.
(1) Loop back test for communication using MC protocol
The loop back test is a function designed to check the following:
• Whether a line has been properly connected to the test target Ethernet module.
• Whether the parameters for the Ethernet module have been correctly set.
• Whether the initial processing for the Ethernet module has been completed
normally.
• Whether the program for the external device is running correctly.
(2) It is necessary to connect lines when performing communication using MC
protocol with the user port on the Ethernet module side.
Perform the open processing for the connection to be used on the Ethernet
module side.
(3) This function can only be used for the Ethernet module of the local station. The
function cannot be used for the Ethernet module of another station via a network
system.
(Loop back test target station)

Ethernet

(Loop back test
target station)

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COMMUNICATION PROCEDURE

MELSEC-F

5.5 Open Settings
This section explains the open setting.
A sequence program can perform open processing (establishing connection) with up
to a maximum of 4 external device stations
Once a connection is established with an external device, it is possible to
communicate using MC protocol, fixed buffer communication.
Thus, the open processing is required even when communicating using MC protocol.

NOTE
When adjusting settings in FX Configurator-EN-L, select the [Open Settings] from
the initial screen and adjust the settings at the [Ethernet Open Settings] screen.

5.5.1 Fixed buffer connection (connection No. 1 and connection No. 2)
Setting item name

BFM number [Decimal]
32, 33
(b8)

Protocol

Open system

Fixed buffer

Description of setting

Setting range/options
OFF : TCP/IP
ON : UDP/IP

Set the communication method (protocol).

00 : Active open
10 : Unpassive open

32, 33
(b15, b14)

Select the connection open system.

32, 33
(b0)

Select the usage of the fixed buffer.

OFF : Send
ON : Receive

Select which protocol is used for fixed buffer communication.

00 : Procedure exist
01 : No procedure

11 : Fullpassive open

Fixed buffer
communication

32, 33
(b10, b9)

Pairing open*1

32, 33
(b7)

Select whether pairing open is used or not.

OFF : Pairs
ON : No pairs

Existence confirmation

32, 33
(b1)

Select whether the continued existence of a destination station
for a connection should be confirmed or not.

OFF : No confirm
ON : Confir

Local station Port No.

40, 47

Destination IP address

41 to 42, 48 to 49

Dest. Port No.

*1

43, 50

Set the local station's port No.

1025 to 5548 or 5552 to 65534

Set the IP address of an external device.

1 to FFFFFFFEH

Set the port No. of an external device.

1025 to 65534

"1 (Pairs)" cannot be selected in connection No. 2.

(1) Protocol
(connection numbers 1, 2; BFM#32, 33 b8)
(a) Select the protocol for each connection.
Name of setting

Description of setting

TCP

Communicate using TCP/IP.

UDP

Communicate using UDP/IP.

(b) For protocols (TCP/UDP), see 1.3, "Software Configuration".

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COMMUNICATION PROCEDURE

MELSEC-F

(2) Open system
(connection numbers 1, 2; BFM#32, 33 b15, b14)
(a) Select the connection open system for each connection for which "TCP" is
selected in "(1) Protocol". If "UDP" is selected, the specification of this item is
not required.
Name of setting

Description of setting

Active

Perform active open processing to an external device that waits for a passive open
(Fullpassive/Unpassive) on the TCP connection.

Unpassive

Perform passive open processing on the TCP connection addressing all the devices connected
to a network.
(The local station is placed in the wait status to wait for an Active open request to be sent.)

Fullpassive

Perform passive open processing on the TCP connection, only addressing specific devices.
(The local station is placed in the wait status to wait for an Active open request to be sent.)
The local station waits for an Active open request from the opposite station set in "(8)
Destination IP address".

Ethernet module

PLC main unit

Initial request
FROM instruction

Initial completion

TO instruction

Fullpass ive/
Unpassove
open
Active open

Initial completion

Ethernet module

PLC main unit

Initial request

FROM instruction

Initial completion

Open
ction

FROM instruction

Initial completion

Wait for open
request

Open request

TO

instru

Active open

FROM instruction
Open completion

Open completion
Open completion

(3) Fixed buffer
(connection numbers 1, 2; BFM#32, 33 b0)
(a) Here it is selected whether the fixed buffer corresponding to each applicable
connection number will be used for sending or receiving when
communicating using the fixed buffers.
Name of setting

Description of setting

Send

For sending.

Receive

For receiving.

(b) When both sending and receiving are performed with an external device
using fixed buffer communication, one buffer for sending and one for
receiving are required. Thus, two connections should be set.

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COMMUNICATION PROCEDURE

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(4) Fixed buffer communication
(connection numbers 1, 2; BFM#32, 33 b9 to b10)
(a) For this item, select the communication method when communicating using
the fixed buffers.
Name of setting

Description of setting

Procedure exist

• In fixed buffer communication, data is communicated in 1:1 by handshaking with the
external device.

No procedure

• The no procedure fixed buffer communication uses dedicated connections.
• The PLC and external devices communicate data in 1:1
• The handshaking with an external device must be performed using a sequence program.

(5) Pairing open
(connection numbers 1 only; BFM#32 b7)
(a) Select whether or not the Ethernet module's receiving and sending
connections are made into one pair and connected to one port of an external
device when using fixed buffer communication (Either one among
[Procedure exist] or [No procedure] can be specified).
For more detail, see [Section 5.7 Pairing Open].
(b) "Pairs" can be selected only in connection No. 1.
If "Pairs" is selected in connection No. 2, an error will occur when the
connections are opened.
• Error information is stored in the error log area (BFM#227 to 511) in the
buffer memory.
• The open error code is stored in BFM#134.
Name of setting

5 - 20

Description of setting

No pairs

Does not use the pairing open method.

Pairs

Uses the pairing open method.

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COMMUNICATION PROCEDURE

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(6) Existence confirmation
(connection numbers 1, 2; BFM#32, 33 b1)
(a) This setting selects whether or not the Ethernet module should confirm that
an external device still operates normally when there is no communication
for a fixed period of time. The open processing for the connection with the
external device must have been completed.
Name of setting

Description of setting

No confirm

Do not confirm the existence of the external device.

Confirm

Confirm the existence of the external device.
For details on the settings of the existence confirmation time and others, see Section 5.2,
"Initial Settings".

(b) When an error occurs in the existence confirmation, the Ethernet module
performs the following processing.
• Forcibly closes the line and stores the error information in the error log
area (BFM#227 to 511) of the buffer memory.
• Turns off the open completion signal (BFM#20480) and stores the open
error code in BFM#124, 134.
(c) If the external device will be changed while a UDP/IP connection is open,
"No confirm" should be selected.
If "Confirm" is selected, the Ethernet module will confirm the existence of the
first destination after the UDP/IP connection is opened. Existence
confirmation is not performed for the changed destination, i.e. the newly
selected external device.

(7) Local station Port No.
(connection numbers 1, 2; BFM#40, 47)
(a) In this item the port number of each connection for the Ethernet module is
set.
(b) The setting values are designated in the range from 1025 to 5548 and from
5552 to 65534. Set port numbers that are not already used by other ports.
(c) Set the port numbers for the Ethernet module upon consulting a network
administrator.

(8) Destination IP address
(connection numbers 1, 2; BFM#41 to 42, 48 to 49)
(a) Set the IP addresses (two words) for external devices in the chosen input
format.
(b) The IP addresses of external devices must be given values other than 0H,
FFFFFFFFH.
(c) Set the IP addresses of external devices upon consulting a network
administrator.

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COMMUNICATION PROCEDURE

MELSEC-F

(9) Destination Port No.
(connection numbers 1, 2; BFM#43, 50)
(a) Set the port numbers of the external devices for each connection.
(b) The port numbers of the external devices are set in the range from 1025 to
65534.
(c) Set the port numbers for the external device upon consulting a network
administrator.
(d) The following table provides some precautions that should be observed
when setting port numbers.
( in the diagram indicates a device and indicates a port number.)
Status of connection establishment
(

: Port (indicates port number))

Description of connection

Communication
protocol
TCP

UDP

External device
Ethernet module
External device

External device
Ethernet module
External device

Ethernet module

External device

When connecting to multiple external devices, set
multiple port numbers for the local station.

When connecting to multiple external devices, set
a single port number for the local station.
(However, it is necessary to open a connection for
each external device)
This cannot be chosen when the local station is
Unpassive.

When connecting to multiple ports of an external
device, set multiple port numbers for the Ethernet
module.
When connecting to multiple ports of an external
device, set a single port number for the Ethernet
module. (However, it is necessary to open a
connection for each external device port)
This cannot be chosen when the local station is
Unpassive.

Ethernet module

External device

Ethernet module

External device

When connecting to the same port of an external
device, set multiple port numbers for the Ethernet
module. (However, it is necessary to open a
connection for each Ethernet module port)

Ethernet module

External device

Setting multiple ports numbers for the same port
of an external device and the Ethernet module is
possible only when pairing open is set.

Important
Make sure to set parameters for connections that communicate by Passive open
or UDP open when [Always wait for OPEN (communication possible at STOP
time)] is selected in the Operation settings (see Section 4.6).

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COMMUNICATION PROCEDURE

MELSEC-F

POINT
Set parameters according to the open method to be used for open connection.
TCP

Communication system
open system

Active
ARP function of external device

Parameter
Communication
address

5 - 23

Yes

UDP

Passive
No

Un-passive

Full-passive

ARP function of external device
Yes

No

Local station Port No.
Destination IP address
Destination Port No.

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COMMUNICATION PROCEDURE

MELSEC-F

5.5.2 MELSOFT/MC protocol connections (connection No. 3 and connection No. 4)
Setting item name

BFM number
[Decimal]

Setting range/options
Description of setting

MELSOFT

MC protocol

connection*1

Protocol Open system Existence confirmation Setting value
Unpassive
Connection usage

Set the connection
usage

34, 35

TCP
Fullpassive
UDP

Set the local station's
port No

Local station Port No.

54, 61

Destination IP address

55 to 56, 62 to 63

Dest. Port No.

*1

*2
*3
*4

57, 64

Set the IP address of an
external device
Set the port No. of an
external device

—

Confirm

Setting value

8403H

No confirm

8401H

Confirm

C403H

No confirm

C401H

Confirm

0503H

No confirm

0501H

A002H*2 *3 *4

1025 to 5548 or 5552 to 65534

Setting is not
required

1H to FFFFFFFEH

Setting is not
required

40H to FFFFH

Setting is not
required

Used to connect MELSOFT products through TCP/IP communication.
It performs passive open processing of TCP connection for all MELSOFT products connected to the
network. (It waits for an Active open request given to its own station.)
Regardless of the initial timing setting in the operation settings (refer to Section 4.6), this connection
will always wait for the open status.
The set connection is used only for data communication with MELSOFT products.
Set connections for all connected MELSOFT products when connecting two or more MELSOFT
products at the same time.
Up to 2 connections can be set.
Number of MELSOFT connections + Number of MC protocol connections

2

(1) Local station Port No. (connection numbers 3, 4; BFM#54, 61)
Select this item when using connections for MC protocol.
(a) In this item the port number of each connection for the Ethernet module is
set in Decimal.
(b) The setting values are designated in the range from 1025 to 5548 and from
5552 to 65534. Set port numbers that are not already used by other ports.
(c) Set the port numbers for the Ethernet module upon consulting a network
administrator.

(2) Destination IP address (connection numbers 3, 4; BFM#55 to 56,
62 to 63)
Select this item when using connections for MC protocol.
(a) Set the IP addresses (two words) for external devices in the chosen input
format (decimal/hexadecimal).
(b) The IP addresses of external devices must be given values other than
0H,FFFFFFFFH.
(c) Set the IP addresses of external devices upon consulting a network
administrator.

(3) Destination Port No. (connection numbers 3, 4; BFM#57, 64)
Select this item when using connections for MC protocol.
(a) Set the port numbers of the external devices for each connection.
(b) The port numbers of the external devices are set in the range from 1025 to
65534.
(c) Set the port numbers for the external device upon consulting a network
administrator.
(d) Refer to Paragraph 5.5.1 (9) for cautions on setting the port number.
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COMMUNICATION PROCEDURE

MELSEC-F

5.6 Open Processing/Close Processing of the Connection
This section explains the open processing/close processing using sequence
programs.

(1) Open processing
(a) The purpose of the open processing is to establish a connection with an
external device in order to perform the following forms of data
communication.
They can be performed with an external device opened by the user.
• Sending/receiving using the fixed buffers (Procedure exists/No procedure)
: Connections No. 1 and 2 only
• Communication using MC protocol ("Unpassive open (MC)" or "Full
passive open (MC)" in the open system setting) must be set.
: Connections No. 3 and 4 only
(b) When the following is set by the parameter settings, the open processing
should be performed in a sequence program.
1) In the Operational settings (Section 4.6)
When "Do not wait for OPEN" is set in the "Initial timing setting".
2) In the open settings (Section 5.5)
When "Active" is set in the "OPEN system" setting.
(c) In order to perform open processing, the initial processing must be complete
(BFM #28b0: ON) and the hub communication status (BFM #28b7: ON) must
be on.
(d) A connection with an external device must be established (open processing)
when communicating using either the MC protocol, fixed buffers. (*1)
Two types of data communication mentioned above can also be performed
with an external device opened by the user.
*1 Since the Ethernet module recognizes the external device by the IP
address, the open processing is required for UDP communication.
(e) Up to a maximum of 4 connections can be opened to external devices.
However, two buffers are required when communicating with the same
external device using fixed buffer communication, so in this case the number
of external devices that can be communicated with will be lower.

POINT
During communication using MC protocol, if data communication is to continue
even after the Ethernet module installed PLC, has been placed in the STOP
status, enable "Always wait for OPEN (communication possible at STOP time)"
under "Initial timing setting" (see 4.6, "Operation Settings").

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COMMUNICATION PROCEDURE

MELSEC-F

(2) Close processing
(a) The purpose of the close processing is to disconnect (cancel) the connection
with the external device established by open processing mentioned
previously.
(b) The close processing is used when terminating a connection with an
external device, changing an external device of a connection, changing
communication conditions, etc.
(c) Perform the close processing for connections established by open
processing using sequence programs.
(d) Determine the timing of close processing with the external device.
The examples in the following sections describe the procedures for establishing a
connection from the Ethernet module to an external device and subsequently closing
it again by open and close processing for connection number 1.
• TCP/IP Active open

: See 5.6.1, "Active open processing/close processing".

• TCP/IP Passive open : See 5.6.2, "Passive open processing/close processing".
• UDP/IP Open

: See 5.6.3, "UDP/IP open processing/close processing".

POINT
Except when the close processing is requested, the open completion signal
(applicable bit of BFM#20480) automatically turns off and the communication line
is closed in the following cases:
(1) When the existence confirmation function times out (see Section 5.5).
(2) When a close or RST command is received from an external device.
(3) When the Active open request is received again from the external device in
the open completion status of TCP.
After returning ACK to the external device, the Ethernet module closes the
connection when the RST command is received from the external device.
However, when receiving the Active open request again from the external
device with a different IP address or port No., the Ethernet module only sends
the RST command. (It does not close the connection.)

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COMMUNICATION PROCEDURE

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5.6.1 Active open processing/close processing
This section explains the procedure for opening and closing a connection with an
external device from the Ethernet module.
• Program example for the unit No. 1
<>
M8000

U1\
G28

[MOV

Status
U1\
G27
H1
Initial
completion
signal

[=

X000

M0

M117

Open
Link
Initial
request completion status
status

]

K4M110 ]
Status read

(M0
Initial
completion
status

M103
(M100
)
Open request
(self-holding)

Cancel of
selfholding
at close

M100

U1\
G1602

[MOV

D100
]
Reading
OPEN
instruction/ value
of #1602
status

[MOVP

H1

Open request
(self-holding)

[=

D100
Reading
value
of #1602

H5

]

U1\
G1602

]
OPEN
instruction/
status
(M101
)
Open
completed

[INCP
D0
]
Normal open processing
Open normal completion
processing

[=

D100
Reading
value
of #1602

H10

]

[=

D100
Reading
value
of #1602

H15

]

[INCP
D1
]
Open abnormal processing
Open abnormal completion
processing

X000
[MOVP

H8000

Open
request

U1\
G1602
]
OPEN
instruction/
status

M102
(M102
)
Closed
(self-holding)

Closed
(selfholding)
[=

D100
Reading
value
of #1602

H0

]

(M103
)
Cancel of
self-holding
at close

[INCP

D2
]
Close count

CLOSE normal
completion processing
[END
User applications are described at the area enclosed with

5 - 27

]

.

5 - 27

5

COMMUNICATION PROCEDURE

Power-on

MELSEC-F

1) Parameter update
completed

Open status
2) Hub connected
Open allowed status

Closed status
Initial normal completion
BFM#27=0001H
Hub connected signal
BFM #28b7
OPEN/ CLOSE instruction
status BFM#1602

3)
OPEN
CLOSE
status instruction
W0001H
0000H

OPEN
processing
0003H

OPEN status
0005H
(OPEN failure
0010H)

CLOSE
instruction
W8000H

CLOSE
status
0000H

CLOSE
processing
0009H

6)
Open completion signal
BFM#20480
Open request signal
BFM#20482
SYN
4)

5)

FIN
7)

8)
FIN+ACK

SYN+ACK

1) After communicating the parameter settings, confirm the normal
completion of the Ethernet module initial processing.
(Initial completion signal BFM#27 "0001H")
2) Confirm that the Ethernet module and hub are connected. (BFM#28
b7:ON)
3) Start the open processing writing with pulse execution instruction 0001H
to BFM#1602.
4) The Ethernet module executes the open processing.
• Sends the open request (SYN).
5) When the open processing completes normally
• Open completion signal BFM#20480 b0

: ON

• BFM#1602 "0005H"
Data communication is enabled.
When the open processing completes abnormally (*1)
• The open error code is stored in the buffer memory.(*2)
• Open error detection (BFM#1602 "0010H" or "0015H")
• Area for module status (BFM#28 b6:ON)
6) Start the close processing writing 8000H to BFM#1602.
7) The Ethernet module executes the close processing.
• Sends the close request (FIN).
8) When the close processing completes normally (*3)
• Open completion signal (BFM#2048 b0)

: OFF

• Open/Close instruction status (BFM#1602 "0000 H ")

5 - 28

5 - 28

5

COMMUNICATION PROCEDURE

MELSEC-F

POINT
This example uses connection number 1 for explanation. Use the corresponding
BFM No. and bits for other connection numbers.
*1

*2

*3

PLC

Open request signal
(CLOSE processing
execution)
Open completion
signal

Processing when the open processing is abnormally completed
(TCP)
When opening from the Ethernet module under a normal situation,
if the Ethernet module sends a SYN, the external device returns
an ACK and a SYN.
However, if the Ethernet module sends a SYN and then the
external device returns a RST, the open abnormal completion
(BFM#28 b6) is immediately turned on and open processing ends.
The open status and error code at abnormal end can be confirmed
with the following buffer memory.
• Each connection open abnormal code area of the
communication status storage area
(Connection numbers 1 to 4; BFM#120 to 159)
• Error log area (BFM#227 to 372)
• Error codes stored in the open error code area are cleared when
writing "0001H" to the BFM #1602 to 1605 to perform the open
operation.
Processing when the close processing is abnormally completed
(TCP) When closing normally from the Ethernet module, the
Ethernet module sends a FIN request and the external device
returns an ACK and a FIN. However, if an ACK and a FIN are not
returned because the external device is faulty, the Ethernet
module forcibly disconnects the connection (sends a RST
message).
1)

2)
Ethernet
module

Close abnormal processing
7)

5)
FIN is not sent after waiting for the TCP
end timer
3)

At normal completion

Ethernet
FIN

5 - 29

4)
ACK

FIN

6)
RST

5 - 29

5

COMMUNICATION PROCEDURE

MELSEC-F

1) The open request signal turns off by writing "8000H" to the BFM#1602.
2) The Ethernet module executes the close processing.
3) The Ethernet module sends a FIN request to the external device.
4) The external device sends back FIN and ACK messages in reply to the
FIN request sent by the Ethernet module.
(When the reply is not returned, the Ethernet module sends the FIN
request again.)
5) The Ethernet module waits for the external device to send an ACK and a
FIN.
(The module waits for the amount of time set in the TCP end timer value.
For details on how to set it, see Section 5.2, "Initial Settings".)
If the ACK and FIN messages are received at this point, it returns an ACK
as in the normal processing.
6) If an ACK and a FIN are not received within the time designated by the
TCP end timer, an RST message is sent to the external device.
7) The Ethernet module determines that the close procedure is completed
and turns off the open completion signal regardless of the status of the
external device.

NOTE
(1) When the procedure above is performed, the Ethernet module determines that
the closing of the external device is executed normally, thus the close
processing result is not stored in the error log area.
(2) The procedure described above is a special function of the Ethernet module; it
is not available for general TCP/IP protocols.

5 - 30

5 - 30

5

COMMUNICATION PROCEDURE

MELSEC-F

Program example
This example explains a program for open processing/close processing when
Active open is selected in the Open system setting.

(1) Execution environment for the program example
(a) The Ethernet module is connected to the second special module. (The unit
number is setting 1)
(b) The unit number specified at the sequence program and FX ConfiguratorEN-L is 1.
(c) Make Operation settings in the following manner.
Communication data code : Binary code (BFM#24 b1 : OFF)
Initial timing
: Do not wait for OPEN (Communications
impossible at STOP time) (BFM#24 b8 : OFF)
IP address
: 10.97.85.222 (0A.61.55.DEH) (BFM#106 to
107)
(d) Make open settings in the following manner.
Protocol
: TCP (BFM#32 b8 : OFF)
Open system
: Active (BFM#32 b14, b15 : 00H)
Fixed buffer
: Send (BFM#32 b0 : OFF)
Fixed buffer communication
procedure
: Procedure exist (BFM#32 b9 : OFF)
Pairing open
: Disable (BFM#32 b7 : OFF)
Existence confirmation
: No confirm (BFM#32 b1 : OFF)
Local station Port No.
: 4096 (BFM#40)
Transmission target device
IP address
: 10.97.85.223 (0A.61.55.DFH) (BFM#41 to 42)
Transmission target device
Port No.
: 8192 (BFM#43)
(e) The following contact signals are used in the program.
Ethernet module status
Connection No.1 open/close status and instruction
(f)

: M110 to M115
: D100

The area enclosed with
in the program example should be used when
the [Open settings] Ethernet module parameters are not set for
FX Configurator-EN-L.
This part of the program is not required when the [Open settings] parameters
are used for FX Configurator-EN-L.

(2) Outline of the program example
(a) After each parameter is set in FX Configurator-EN-L or the sequence
program and written to the Ethernet module, re-initialize or power ON the
module again and confirm the completion of the initial processing via buffer
memory operations.
(b) The Ethernet module performs the open processing for connection No. 1 to
the external device set in the [Open settings] or control data.
(c) The close processing for connection No. 1 is performed according to the
close instruction to the Ethernet module or the close request from the
external device.

5 - 31

5 - 31

5

COMMUNICATION PROCEDURE

MELSEC-F

• Program example for the unit No. 1
M8000
[MOV
U1\
H1
G27
Initial
completion
signal

[=

X000

M0

M117

M103

Initial
Link
Open
request completion status
status
M100

Cancel
of selfholding
at close

U1\
G28
Status

]

K4M110 ]
Read of status
(M0
Initial
completion
status

(M100
)
Open request
(Self-holding)
U1\
[MOV
D100
]
G1602
OPEN instruction Reading value
transmission
of #1602
completed

Open request
(Self-holding)

[MOVP

H0

[MOVP

K4096

[DMOVP H0A6155DF

[=

D100
Reading
value
of #1602

H5

[MOV

K8192

[MOVP

H1

]

[=

D100
Reading
value
of #1602

H10

]

[=

D100
Reading
value
of #1602

H15

]

U1\
]
G32
Connection
No.1
application
U1\
]
G40
Host port
No.
U1\
]
G41
Target IP
address
U1\
G43
Target
port No.

]

U1\
]
G1602
OPEN
instruction
transmission
completed
(M101
)
Open
completed

[INCP

D0
]
Open
normally
completed

[INCP

D1
]
Open
abnormally
completed

X000
[MOVP

H8000

Open
request
M102

U1\
]
G1602
OPEN
instruction
transmission
completed

User applications are
described at the area
enclosed with
.

(M102
)
Closed
(Self-holding)

Closed
(Selfholding)
[=

D100
Reading
value
of #1602

H0

]

(M103
)
Cancel of
self-holding
at close
[INCP

D2
]
Close normal
completion
count
[END

5 - 32

The area inside
indicates a program example
when "Open settings" is not
provided in the parameter
settings for the Ethernet
module using FX ConfiguratorEN-L.

]

5 - 32

5

COMMUNICATION PROCEDURE

MELSEC-F

5.6.2 Passive open processing/close processing
This section explains the procedure for opening and closing a connection with the
Ethernet module via an external device.
The operations of Passive open processing/close processing differ depending on
whether "Always wait for OPEN" or "Do not wait for OPEN" is selected, as shown in
this section.

(1) When "Always wait for OPEN" is selected in the operational setting
This is an explanation of (BFM #24 b8: ON) open processing/close processing
when initial timing settings for Operational Settings are set to be always wait
OPEN (Communication Possible at STOP).
In this case, sequence programs for open processing and close processing are
not required because the Ethernet module keeps the connection in the always
wait for the OPEN status according to the [Open settings] parameter setting.
For detail on the [Open settings] parameter, see Section 5.5, "Open Settings".
Parameter
communication
Power-on completed 1)
Open status
Open allowed status
(Listen status)
(Active open acknowledge
enabled)
Close status

( *1 )

Initial normal completion
BFM#27="0001H"
4)

Open completion signal
BFM#20480
Open allowed status
BFM#20482

SYN + ACK
2)
SYN

*1

5 - 33

FIN + ACK
3)
FIN

An open request (SYN) received after the normal completion of an
initial processing and before the Ethernet module is placed in the
open acknowledge enabled status generates an error, and the
Ethernet module sends a connection forced close (RST).

5 - 33

5

COMMUNICATION PROCEDURE

MELSEC-F

1) After the parameters are sent, the normal completion of the Ethernet
module initial processing is confirmed (Initial normal completion signal
BFM#27 "0001H")
After the initial processing is normally completed, the connection is
placed in the open allowed status and the Ethernet module waits for an
open request from the external device.
2) The Ethernet module starts the open processing upon receiving the open
request (SYN) from the external device.
When the open processing is normally completed (Open/close status
(BFM#1602 "0005H")), the open completion signal (BFM#20480 b0) turns
on and data communication is enabled.
3) The Ethernet module starts the close processing upon receiving the
close request (FIN) from the external device.
When the close processing is completed (BFM#1602 "0000H"), the open
completion signal (BFM#20480 b0) turns off and data communication is
disabled.
4) After the Ethernet module's internal processing is Rissn/completed, the
connection returns to the open acknowledge enabled status.

NOTE
For Passive open connections for which [Always wait for OPEN (Communication
possible at STOP time)] is selected in [Operational settings], the connection open/
close processing of the Ethernet module side is performed according to the open/
close request from the external device.
When the close processing is performed from the Ethernet module (this station), the
applicable connection will not return to the open acknowledge enabled status after
the close processing, even if [Always wait for OPEN (communication possible at
STOP time)] is selected in [Operational settings].
(It requires the same open processing and close processing as the connection for
Passive open for which [Do not wait for OPEN (communication impossible at STOP)]
is selected.)

(2) When "Do not wait for OPEN" is selected in the operational setting
When initial timing settings of operational settings are at [Do not wait for OPEN
(communication impossible at STOP time)], the (BFM #24 b8: OFF) open
processing/close processing is performed as explained below.
Since open processing/close processing is executed by a sequence program, an
external device can be changed while the connection is established.

5 - 34

5 - 34

5

COMMUNICATION PROCEDURE

MELSEC-F

• Program example for the unit No. 1
X0:ON Open
X0:OFF Close
M8000
[MOV

U1\
G28
Status

U1\
G27
H1
Initial
completion
signal

[=

X000

M0

Open
Initial
request completion
status

]

K4M110 ]
Read of status

(M0
Initial
completion
status

M103
)
(M100
Open
request
(Selfholding)

Cancel of
selfholding
at close

M100

[MOV

Open request
(Self-holding)

[MOVP

U1\
G1602
]
D100
Reading
OPEN
instruction/ value
of #1602
status

U1\
G1602

H1

]
OPEN
instruction/
status

[=

D100
Reading
value
of #1602

H3

]

)
(M101
Rissn/Open
completed

[=

D100
Reading
value
of #1602

H5

]

[INCP
D0
]
Number of normal open completions

[=

D100
Reading
value
of #1602

H10

]

[=

D100
Reading
value
of #1602

H15

]

Normal open

[INCP

X000
[MOVP
Open
request

M102

H8000

D1
]
Number of
abnormal
open
completions

U1\
G1602

]
OPEN
instruction/
status

)
(M102
Closed
(Selfholding)

Closed
(Selfholding)
[=

D100
Reading
value
of #1602

H0

]

)
(M103
Cancel of
self-holding
at close

[INCP
D2
]
Close normal completion count
Close normal processing

[END
User applications are described at the area enclosed with

5 - 35

]

.

5 - 35

5

COMMUNICATION PROCEDURE

Power-on

Open status

MELSEC-F

Parameter
communication
completed
1)

Open allowed status (closed)
(Active open acknowledge
enabled)

(*1)

Closed status
Initial normal completion
BFM#27="0001H"

2)
8000H

0001H

OPEN/ CLOSE operation
TO BFM#1602

0001H

3)
OPEN/ CLOSE status
FROM BFM#1602

0000H

0003H

0005H

0009H

0000H

0003H

Open completion signal
BFM#20480
Open allowed status
BFM#20482

4)

SYN+ACK

SYN

*1

FIN+ACK
5)
FIN

If an open request (SYN) received after the normal completion of an
initial processing and before the Ethernet module is placed in the
open acknowledge enabled status, an error is generated, and the
Ethernet module sends a connection forced close (RST).

1) After communicating the parameter settings, confirm the normal
completion of the Ethernet module initial processing.
(Initial normal completion signal (BFM#27 "0001H":)
2) Start the open processing by writing "0001H" to the BFM#1602.
(Open request signal (BFM#20482 b0) : ON
3) OPEN possible (Listen status) from external device. (Open/close status
BFM #1602 "0003H")
4) The Ethernet module starts the open processing upon receiving the open
request (SYN) from the external device.
At normal completion
• Open completion signal (#BFM20480 b0)

: ON

• BFM#1602

: 0005H

Data communication is enabled.
At abnormal completion
• Open completion signal

: OFF

• The open error code is stored in the buffer memory
• Open abnormal detection signal (BFM28 b6)

: ON

• OPEN/CLOSE instruction status (BFM#1602 "0010H" or "0015H")
5) The Ethernet module starts the close processing upon receiving the
close request (FIN) from the external device.
When the close processing is completed, the open completion signal
turns off and data communication is disabled.
5 - 36

5 - 36

5

COMMUNICATION PROCEDURE

MELSEC-F

POINT
This example uses connection number 1 for explanation. Use the appropriate
BFM signals and bits for other connection numbers.

NOTE
(1) If the settings of the connection need modifying, the modifications should be
done before writing the open instruction to the buffer memory.
(2) Once open processing is executed, an open request cannot be canceled before
the open processing is completed.
Write the close instruction to the buffer memory after the open processing has
been completed.

5 - 37

5 - 37

5

COMMUNICATION PROCEDURE

MELSEC-F

Program example
This example explains a program for open processing/close processing when
Unpassive open is selected in the open system setting.

(1) Execution environment for the program example
(a) The Ethernet module is connected to the second special module. (The unit
number is setting 1)
(b) The unit number specified at the sequence program and in FX ConfiguratorEN-L is 1.
(c) Adjust Operation settings in the following manner.
Communication data code : Binary code (BFM#24 b1 : OFF)
Initial timing
: Do not wait for OPEN (Communications
impossible at STOP time) (BFM#24 b8 : OFF)
IP address
: 10.97.85.223 (0A.61.55.DFH) (BFM#106 to 107)
(d) Make open settings in the following manner.
Protocol
Open system
Fixed buffer
Fixed buffer
communication procedure
Pairing open
Existence confirmation
Local station Port No.

: TCP (BFM#32 b8 : OFF)
: Unpassive (BFM#32 b14, b15 : 10H)
: Send (BFM#32 b0 : ON)
: Procedure exist (BFM#32 b9 : OFF)
: Disable (BFM#32 b7 : OFF)
: No confirm (BFM#32 b1 : OFF)
: 8192 (BFM#40)

(e) The following contact signals are used in the program.
X000 Open instruction
M100 Open request self-hold
M101 Open complete
M102 Closed indicator self-hold
M103 Cancel self-hold when closed

(2) Outline of the program example
(a) The open processing for connection No. 1 of the Ethernet module is
performed.
After the completion of the open processing, connection No. 1 waits for the
open request from the external device.
(b) The close processing for connection No. 1 is performed according to the
close instruction (X000=OFF) to the Ethernet module.

5 - 38

5 - 38

5

COMMUNICATION PROCEDURE

MELSEC-F

• Program example for the unit No. 1
M8000
[MOV

U1\
H1
G27
Initial
completion
signal

[=

X000

M0

M103

Open
request

Initial
completion
status

Cancel of
selfholding
at close

U1\
G28
Status

]

K4M110 ]
Read status

(M0
Initial
completion
status

)
(M100
Open
request
(Selfholding)

M100

[MOV

Open request
(Self-holding)

[MOVP

U1\
D100
]
G1602
Reading
OPEN
instruction/ value
of #1602
status

H1

U1\
]
G1602
OPEN
instruction/
status
)
(M101
Rissn/Open
completed

[=

D100
Reading
value
of #1602

H3

]

[=

D100
Reading
value
of #1602

H5

]

[INCP

D0
]
Number of
normal
open
completions

[=

D100
Reading
value
of #1602

H10

]

[INCP

D1
]
Number of
abnormal
open
completions

[=

D100
Reading
value
of #1602

H15

]

X000
[MOVP

H8000

Open
request

M102

U1\
]
G1602
OPEN
instruction/
status

)
(M102
Closed
(Selfholding)

Closed
(Selfholding)

[=

D100
Reading
value
of #1602

H0

]

)
(M103
Cancel of
self-holding
at close

[INCP

D2
]
Close normal
completion
count
[END

User applications are described at the area enclosed with

5 - 39

]

.

5 - 39

5

COMMUNICATION PROCEDURE

MELSEC-F

5.6.3 UDP/IP open processing/close processing
The following explains the UDP/IP open processing.
The operations of the open processing/close processing in UDP/IP differ depending
on whether "Always wait for OPEN" or "Do not wait for OPEN" is selected in the initial
timing settings (BFM #24 b8) from operational settings.

(1) When "Always wait for OPEN" is selected in the operational
settings (Communications possible at STOP time)
According to the Open settings (BFM#32), a selected connection for the UDP/IP
communication is established automatically after the Ethernet module installed
station has been restarted, and data transmission/reception is enabled.
Sequence programs for open processing and close processing are not required.
For details on the [Open settings] parameter, see Section 5.5, "Open Settings".

NOTE
When performing the open and close processing by writing to the buffer memory
from the Ethernet module side, even if [Always wait for OPEN (Communications
impossible at STOP time)] is selected at [Operational settings], it is required to use
the sequence program to process all that follows the processing for the applicable
connection.
If "Do not wait for OPEN (Communication impossible at STOP time)" is selected,
open processing and close processing need to be done in the same manner as a
connection.

(2) When "Do not wait for OPEN" is selected in the operational settings
(Communications impossible at STOP time)
In this case, the open processing and close processing in the sequence program
shown in the next page are required. Data transmission and reception are
enabled after the open processing is normally completed.
Perform the open processing and close processing by writing "0001H" in
BFM#1602 to 1605.

5 - 40

5 - 40

5

COMMUNICATION PROCEDURE

MELSEC-F

• Program example for the unit No. 1
<>
M8000
[MOV

U1\
H1
G27
Initial
completion
signal

[=

X000

M0

Open
request

Initial
completion
status

U1\
G28
Status

]

K4M110 ]
Status
read value
(M0
Initial
completion
status

[MOVP

[MOV

H1

U1\
G1602
]
OPEN
instruction/
status

U1\
G1602
D100
OPEN
instruction/
status

]

[=

D100

H5

]

[INCP

D0
]
Open
normal
completion
signal

[=

D100

H10

]

[INCP

D1
]
Open
abnormal
processing

[=

D100

H15

]

<>
X001
[MOVP

H8000

Close
request

[=

U1\
H0
G1602
OPEN
instruction/
status

]

[INCP

U1\
G1602
]
OPEN
instruction/
status
D2
]
Closel
normal
processing
[END

User applications are described at the area enclosed with

5 - 41

]

.

5 - 41

5

COMMUNICATION PROCEDURE

Power-on

MELSEC-F

Parameter
update completed

Open status
1)

Closed status
Initial normal completion
BFM#27=001

2)
OPEN/CLOSE instruction
and status BFM#1602

Open completion signal
BFM#20480

R
0000H

W0001H

3)

R0005H

4)
Internal
processing

W
8000H

R
0009H

6)

R
0000H

7)
Internal
processing

1) After communicating the parameter settings, confirm the normal
completion of the Ethernet module initial processing.
(Initial normal completion signal (BEF#27) : 0001H)
2) Start the open processing by writing 0001H to the BFM#1602.
(Open request signal (BFM#20482 b0) : ON)
3) The Ethernet module executes the open processing.
(Internal processing only)
4) When the open processing completes normally
• Open completion signal (BFM#20482 b0)
• Reading value of BFM#1602

: ON
: 0005H

Data communication is enabled.
When the open processing completes abnormally
• Open status (BFM#1602)
• Open abnormal detection signal (BFM#28 b6)

: 0010H or 0015H
: ON

5) Start the close processing by writing 8000H to the BFM#1602.
6) The Ethernet module executes the close processing.
(Internal processing only)
7) When the close processing completes normally
• Open/Close instruction status (BFM#1602)

5 - 42

: 0000H

5 - 42

5

COMMUNICATION PROCEDURE

MELSEC-F

5.7 Pairing Open
The following explains communication using the paring open method via the Ethernet
module.

5.7.1 Pairing open
Pairing open is an opening method for establishing a connection in which the local
station and the external device use a single port for each, by pairing the receiving and
sending connections through fixed buffer communication (both the procedure exists
and no procedure are allowed) of the Ethernet module.
By designating the pairing open method, data communication can be performed with
two connections by performing open processing for only one port.
The procedure for performing the open/close processing for pairing open is explained
below.
[Example]
(TCP/IP or UDP/IP communication)

Ethernet module
Connection No. 1 fixed buffer (for receiving)

Send data
External device

Port
Receive data

Connection No. 2 fixed buffer (for sending)

POINT
(1) When setting the pairing open method, the fixed buffer of the applicable
connection number (for receiving only) and the fixed buffer of the next
consecutive connection number (for sending only) are paired in the order of
receiving, then sending.
For the applicable connection (for receiving only), choose connection No. 1.
(2) The range of external devices that can be communicated by the pairing open
method are limited to devices on the Ethernet to which the Ethernet module is
connected and devices connected with the router relay function (see Section
5.3, "Router Relay Parameter").
(3) By the open/close processing of the applicable connection (for receiving only)
for which the pairing open method has been set, the open/close processing of
the next connection (for sending only) will automatically be performed.

5 - 43

5 - 43

5

COMMUNICATION PROCEDURE

MELSEC-F

5.7.2 Example of pairing open settings
This section explains the settings in order to communicate in the pairing open method
by giving an example.
• Connection No. 1 and 2 are used.
(When connection No. 1 is specified at pairing open settings, connection No. 2 is
automatically used as pairing.
Therefore, connection No. 2 cannot be specified as pairing.)
[BFM#32 Connection usage setting area]

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

(1) Fixed buffer
(2) Existence confirmation

(3) Pairing open

(4) Protocol
(5) Fixed buffer communication

(6) Open system

(1) Fixed buffer (BFM#32 b0)
In the open pairing, the applicable connection No. and the subsequent
connection No. are paired. Set the applicable connection No. to "Receive" and
the next connection number to "Send".

(2) Existence confirmation (BFM#32 b1)
If existence confirmation is going to be executed, set the receiving connection to
"Confirm".
If existence confirmation is not going to be executed, select "No confirm".

(3) Pairing open (BFM#32 b7)
Set connection No. 1 as the receiving connection by selecting "Pairs", and set
connection No. 2 as the sending connection by selecting "No pairs".

(4) Protocol (BFM#32 b8)
Both "TCP/IP" and "UDP/IP" are allowed.

(5) Fixed buffer communication (BFM#32 b9, b10)
Both "Procedure exist" and "No procedure" can be selected.

(6) Open system (BFM#32 b14, b15)
All the open systems - "Active", "Unpassive", and "Fullpassive" - can be set.

5 - 44

5 - 44

5

COMMUNICATION PROCEDURE

MELSEC-F

(7) Local station Port No. (BFM#40, 47)
Set this for the receiving connection for receiving only. (Setting is not required for
the sending connection.)
Set the port number upon consulting a network administrator.

(8) Destination IP address (BFM#41 to 42, 48 to 49)
(a) If the setting is not required
• Open system: At [Unpassive] setting
(b) If the setting is required
Set for the receiving connection only upon consulting a network
administrator.
• Open system: At [Active] and [Fullpassive] setting
• Protocol: At [UDP/IP] setting

(9) Destination Port No. (BFM#43, 50)
(a) If the setting is not required
• Open system: At [Unpassive] setting
(b) If the setting is required
Set for the receiving connection only upon consulting a network
administrator.
• Open system: At [Active] and [Fullpassive] setting
• Protocol: At [UDP/IP] setting

NOTE
When making settings in the FX Configurator-EN-L, select [Open Settings] from the
initial screen and at the [Ethernet Open Settings] screen, set "Pairing Open" to
"Yes".

5 - 45

5 - 45

5

COMMUNICATION PROCEDURE

MELSEC-F

5.8 Hub Connection Status Monitor Function
The current connection status of the Ethernet module and hub, the transmission
speed, and the number of times the Ethernet module detected disconnection can be
checked at the following buffer memory addresses.

10BASE-T/100BASE-TX,
Full duplex/half duplex

Hub

Ethernet module

External device

(1) Hub connection status area (BFM#201)
Stores the current connection status of the FX3U-ENET-L and hub and the
transmission speed.

BFM#201

b15 b14 b13

b11 b10 b9

3)

2)

b8

b0

1)
1) Communication mode
0: Half duplex
1: Full duplex

*1

2) Hub connection status
0: Hub not connected/disconnected
1: Hub connected
3) Data transmission speed
0: Operating at 10BASE-T
1: Operating at 100BASE-TX
(Bits other than above are reserved for system use.)
*1 When a switching hub is used, it may not be displayed correctly.

(2) Disconnection detection count storage area (BFM#20995)
(a) Stores the number of disconnection detection times after initial processing is
completed.
Disconnection is detected in any of the following cases.
• Disconnection between Ethernet module and hub
• Cable removal from hub side connector
• Hub power-off
• Cable removal from Ethernet module side connector
(b) If an error has occurred 65536 times or more, a count stops at FFFFH
(65535).
Write "0" to this area using a sequence program to clear the stored value.

5 - 46

5 - 46

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6 FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)
This chapter explains how the PLC and external device communicate in a 1:1 mode
using the fixed buffers (with the procedure exist control method) of the Ethernet
module.

6.1 Control Method
The following explains how communication is performed using the fixed buffers and
the procedure exist control method.
In communication using the fixed buffers, data transmission from the PLC and the
external device is executed through handshaking.
(1) The data flow during communication is as follows.
(For sending)
TO instruction (Transmission request)

FX3U
main
unit

Fixed buffer

FROM instruction (Transmission complete)
(For receiving)

No.1
No.2

External device

FROM instruction (Reading the data received)

TO instruction (Reception complete)

(2) Data can be communicated with the following external devices.
• Device on the Ethernet to which the Ethernet module is connected.
• Devices connected with the router relay function (see Section 5.3)
As shown in the diagram below, when using each fixed buffer (No. 1, No. 2), the
destination devices and usage conditions (for sending/receiving, procedure exist/
no procedure, etc.) should be set when the connection via the Ethernet module is
opened to fix the external device for each buffer.
(a) At TCP/IP communication
It is allowed to change external devices only when the open completion
signal of the applicable connection is off.
(b) At UDP/IP communication
External devices can be changed regardless of the status of the applicable
connection.
("Destination IP address" and "Destination Port No." in the communication
address setting area can be changed. However, the "Local station Port No."
cannot be changed.)
When changing external devices, do not use the "Pairing open" and
"Existence confirmation" functions.

6-1

Fixed buffer No. 1

For sending to external device 1

Fixed buffer No. 2

For receiving from external
device 1

External device 1

6-1

6

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F

POINT
In communication where the procedure exist control method is selected, the data
can be communicated by the following methods after the open processing is
completed.
• Fixed buffer communication with the procedure exist control method (sending or
receiving)
(3) At data sending/receiving, the Ethernet module processes the following.
(a) When sending data
In response to the fixed buffer communication transmission request (write
"0001H" to BFM #1610, #1611), the Ethernet module sends the data of the
fixed buffer stored in the fixed buffer area (BFM #1664 to 3711) to the the
specified external device (BFM #40 to 53). (*1)
(b) When receiving data
The Ethernet module processes the received data if the data is received
from an external device set in the communication setting area that
corresponds to fixed buffer No. n. (*1)
If data is received from an external device not set in the connection
information area of the buffer memory, the Ethernet module ignores the
received data to the PLC side.

6

*1 In case of TCP/IP Unpassive open, data is communicated with an
external device stored in the connection information area corresponding
to fixed buffer No. n.

6-2

6-2

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.2 Sending Control Method
This section explains the control method when data is sent from the Ethernet module
to an external device using the fixed buffer No. 1 and the area corresponding to
connection No. 1 as an example.
• Program example for the unit No. 1
* <>
U1\
G28

M8000
[MOV

K4M300 ]
Initial
completed

* <>
X002

M300

M307
[=

Send
Initial
HUB
instruction completed connection
completed

U1\
G1602
H5
OPEN
instruction/status

M201
]

Transmission
M202 abnormally completed

(M200
)
Send
instruction
(Self-holding)

Transmission
normally
completed

M200
[MOVP

K32

Send instruction
(Self-holding)

U1\
G1664
]
Number of
send words
in the fixed
buffer No.1

U1\
G1665
[BMOVP D1000
K32
Head of
Fixed
send data buffer No.1

[MOVP

[MOV

H1

]

U1\
G1610
]
Transmission
request/status

U1\
G1610
D101
]
Transmission Value of
request/status BFM#1610

D101.2
Value of
BFM#1610

(M201
)
Transmission
normally
completed

D101.3
Value of
BFM#1610

(M202
)
Transmission
abnormally
completed
[END

6-3

]

6-3

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F

Initial
Open
Send data
processing processing writing
Initial processing normally
completed BFM#=0001H
HUB connection is signal
BFM #28 b7

OPEN/CLOSE instruction status
BFM#1602=0005H

Write the send data word
count and the send data
in BFM

Response
receiving

Data sending

1)
2)
3)
4)
TO

8)

5)

R
0004H(Success)/0008H(Error issued)

ACK (TCP only)

Response

6)

R
0002H

ACK (TCP only)

W
0001H

Data sending

Fixed buffer send instruction
and transmission completion
BFM#1610

7)

1) Confirm the normal completion of the initial processing.
2) Confirm that the link status is normal between the Ethernet module and
the connected HUB.
3) Confirm the normal completion of the open processing of connection
No. 1
4) Write the send data word count and the send data in the fixed buffer data
area (communication address setting area: BFM#1664 to 2687) by TO
instruction.
5) Write "0001H" in the fixed buffer communication transmission request
(BFM#1610).
6) The size of send data in the fixed buffer (No. 1) area designated by the
send data length is sent to the designated external device (set in the
open processing).
The value in BFM#1610 becomes "0002H".
7) Upon receiving the data from the Ethernet module, the external device
returns a "Response" to the Ethernet module.
8) Upon receiving the "Response" from the external device, the Ethernet
module ends the data transmission.
If the "Response" is not returned within the response monitoring time
values (see Section 5.2), a data send error occurs.
At normal completion
Fixed buffer transmission result (BFM#1610)

: 0004H

At abnormal completion
Fixed buffer transmission result (BFM#1610)
: 0008H
If the data transmission is abnormally completed, execute the send
process again writing "0001H" in BFM#1610.

6-4

6-4

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F

POINT
The destination setting (see Section 5.5) for a connection whose parameters are
set in FX Configurator-EN-L becomes valid when the open completion signal
(BFM#20480 corresponding bit) of the Ethernet module switches from off to on.
The setting also becomes valid when the each value in BFM#1602 to #1605 is
"0005H" for Connection No.1 to 4.

6-5

6-5

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.3 Receiving Control Method
This section explains the control method when the Ethernet module receives data
from an external device.

6.3.1 Receive processing with the main program
This section explains the receiving process to be performed with the main program,
using an example in which the fixed buffer No. 2 and the area corresponding to
connection No. 2.
• Program example for the unit No. 0
* <>
* 
D100

]

* 
U0
[MOV
D101
]
G2688

]

* 
]

* 

* 

[INCP

]

D102

]

]

Receive abnormal processing
[END
User applications are described at the area enclosed with

Initial
Open
processing processing

]

.

Response
sending

Data
receiving

Initial processing normal
completion

1)

Received word count and
received data written to PLC

FROM instruction

3)
Fixed buffer received status and
received completion message
BFM #1611

Data receiving

R
0001H

ACK
(only TCP)
2)

6-6

4)
6)

W
0002H

R
0004H (Success)/0008H (Error issued)

Response

OPEN/CLOSE instruction status
BFM #1602=0005H

ACK
(only TCP)
5)

6-6

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
1) Confirm the normal completion of the open processing of connection
No. 2.
2) Upon receiving data from the designated external device (set in the open
processing), the Ethernet module processes the following.
• Stores the received data to the fixed buffer (No. 2) area.
Receive data length

: The head address area of the target fixed
address

Receive data

: Area beginning from the head address of the
target fixed buffer + 1

• Fixed buffer receive status signal (BFM#20485 b1)

: ON

• Fixed buffer communication receive result (BFM#1611) : 0001H
3) Execute the FROM instruction to read the received word length and
received data to the PLC.
4) Execute the TO instruction to write "0002H" in the fixed buffer
communication receive result (BFM#1611).
5) Return "Response" to communication destination.
6) The receive processing is performed.
At normal completion
• Fixed buffer transmission results (BFM#1611)

: 0004H

At abnormal completion
• Fixed buffer transmission results (BFM#1611)

: 0008H

POINT
(1) The destination setting (see Section 5.5) for a connection whose parameters
are set with FX Configurator-EN-L becomes valid when the open completion
signal (BFM#20480 corresponding bit) of the Ethernet module switches from
off to on.
(2) Execute data receiving process when the corresponding connection's bit in
the fixed buffer receive status signal storage area (BFM#20485) of the buffer
memory switches from off to on or when the value "0001H" is stored in the
fixed buffer communication receive results (BFM#1610, 1611).
(3) At abnormal data receiving, each buffer memory status is shown in the
following.
(For connection No. 2)
• The fixed buffer receive completion signal (BFM#20485 b1) remains off.
• The fixed buffer communication receive result (BFM#1611) remains
"0008H".
• Data is not stored in the fixed buffer (No.2) area.

6-7

6-7

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.4 Data Format
When communicating between the Ethernet module and an external device, the data
format explained below is used.
The communication data consists of a "header" and "application data" as follows:
Header

Application data

Maximum of 2040 bytes

6.4.1 Header
The header for TCP/IP or UDP/IP is used. In case of the Ethernet module, the
Ethernet module adds and deletes the header. Thus, the user does not need to set it.
(Details of the size of the header section)
1) In case of TCP/IP

Ethernet
14 bytes

IP
20 bytes

TCP
20 bytes

2) In case of UDP/IP

Ethernet
(14 bytes)

6-8

IP
(20 bytes)

UDP
(8 bytes)

6-8

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.4.2 Application data
As shown below, the data code in the application data can be expressed in either
binary code or ASCII code. Switching between binary code and ASCII code is
performed via the communication data code setting (BFM #24 b1 OFF: binary code,
ON: ASCII code).
(When setting using the FX Configurator-EN-L, select [Operational Settings] from the
initial screen, and adjust the settings from the [Operational Settings] screen.)
For more details, see Section 4.6, "Operational Settings".

(1) Format
(a) Communication using binary code
Application data section
(command message)

Communication
request
source side

Maximum
1017 words
(2 bytes used per word)

2 bytes

2 bytes

Subheader

Data length
setting

L

H

L

Text
(command)

H

Communication request
destination side

Subheader

End code

1 byte

1 byte
Application data section
(response)

(b) Communication using ASCII code
Application data section
(command message)

Communication
request
source side

Maximum
508 words
(4 bytes used per word)

4 bytes

4 bytes

Subheader

Data length
setting

H -

-

L

H

-

-

Text
(command)

L

Communication request
destination side

Subheader
H

L

2 bytes

End code
H

L

2 bytes

Application data section
(response)

6-9

6-9

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(2) Subheader
The format of the subheader is as shown below.
The user does not need to set the subheader when using the Ethernet module
since the Ethernet module adds and deletes it.
b7

b6

b5

b4

b3

b2

b1 b0

1

1

0

0

0

0

0

Command/response type
(The bit status indicated in the figure shows that
communication using fixed buffers is being performed.)
Command/response flag
At command
0
At response
1
Command
to

b7
0

1

1

0

Communication using
binary code

0

0

0

b0

b7

0

1

Response
to
1

1

0

60H 00H

0

"6"
Communication using
ASCII code

1
6H

0

0

0
"0"

36H 30H 30H 30H
Subheader

6 - 10

0

0

Subheader

to
1

0

E0H

Subheader
b7

0

b0

0
0H

b0

b7

0

1

b0

to
1
"E"

1

0

0

0
"0"

EH

45H

0

0

0H

30H

Subheader

6 - 10

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(3) Data length setting
This value indicates the data size of the text (command) section.

POINT
The data length can be designated in the following range:
• Communication using binary code
: Maximum of 1017 words
• Communication using ASCII code

: Maximum of 508 words (*1)

*1 Since data is sent/received as ASCII data, the communication data size is
approximately half of the data size when using binary code.

(4) Text (command)
The format of the command/response when communicating using fixed buffers is
configured as follows.
(a) Communication using binary code
Command format
Maximum of 1017 words

60H
Data designation/
storage device
for sending/
receiving instructions

(H)

(L)

(H)

(L)

(H)

(L)

(H)

(L)

(H)

Subheader

n

Send/
receive
data

00H (L)

Data length
setting

n+1

(H)

(L)

n+2

(H)

(L)

n+3

(H)

(L)

(H)

(L)

n+ Data length
setting

1 word (2 bytes)

6 - 11

6 - 11

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(b) Communication using ASCII code
Command format
Maximum of 1016 words

(H) to (L)

36H 30H 30H 30H

(H) to (L)

(H) to (L)

(H) to (L)

Subheader

Data designation/
storage device
for sending/
receiving instructions

Send/
receive
data
(Maximum of
508 words)

ASCII-BIN conversion

n

Data length
setting

n+1

(H)

(L)

n+2

(H)

(L)

(H)

(L)

n + data length
setting

1 word (2 bytes)

(Example)

36H

30H

30H

Subheader

n+1

12H

34H

n+2

56H

78H

30H

30H

30H

30H

Data length

32H

31H
(H)

32 H

33H
to

34H

35H

(L)

(H)

36H

37H
to

38H
(L)

(5) End codes
For more details on the end codes added to a response when communicating
using fixed buffers, see Subsection 11.4.1.
End codes are stored in the communication status storage area of the buffer
memory.

6 - 12

6 - 12

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.5 Programming
This section explains the programming method when the Ethernet module
communicates with an external device using fixed buffers and the procedure exist
control method.

6.5.1 Precautions when creating programs
(1) In order to communicate using the fixed buffer, the initial processing and the
connection open processing must be completed.
(2) The contents of the parameter settings have been loaded into the Ethernet
module when the Ethernet module open completion signal (BFM#20480
corresponding bit) switches from off to on.
(3) The data length (word count) is established using the instruction for procedure
exist communication control method.
If the send data length exceeds this range at data sending, a communication
error occurs and the data is not sent.
(4) Reading or writing to the buffer memory using fixed buffer communication.
• Data sending
Write the send data in the buffer memory (BFM#1664 to #3711).
Write "0001H" in BFM#1610, #1611 to send the data.
• Data receiving
Check the data received (BFM#1610, #1611: "0001Hs") and read the received
data to the PLC (BFM#1664 to #3711).
After reading out, write "0002H" in BFM#1610, #1611 to send the response.
(5) The following should be observed when using a connection opened by UDP.
External devices can be switched by modifying the setting values in the
communication address setting area of the communication parameter setting
area before sending/receiving data. Thus, data can be sent to multiple external
devices sequentially. When sending/receiving, make sure to switch between
external devices properly so that no communication problems occur.
(6) For data (command) transmission, the next data (command) should be after the
data commnication is complete (such as after receiving a response) for the
transmission of the previous data (command).

6 - 13

6 - 13

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
6.5.2 Fixed buffer communication program example (with the procedure exist control method)
This section explains the programming method in order to communicate data
(procedure exist control method) with an external device using the fixed buffers.

FX3U-1st station

FX3U-2nd station

(1) Execution environment for the program example
(a) Send program (FX3U-1st station)
1) Connection No. 1 is used for fixed buffer sending.
2) The unit number specified in the sequence program and
FX Configurator-EN-L is 0.
3) The communication parameter settings are assumed to have been set as
described in Subsection 5.6.1, "Active open processing/close
processing".
(see the table below)
4) Fixed buffer No. 1 send data
: Stored in D1000 to D1031
5) Fixed buffer No. 1 send instruction complete device
: M201
6) Fixed buffer No. 1 send instruction abnormal complete device
: M202
7) Fixed buffer No. 1 send instruction complete status
: D101
[Operational settings]
Setting name
Communication data code setting

Settings in FX Configurator-EN-L
Binary code
Do not wait for OPEN

Initial timing

(Communications impossible at STOP time)

Settings in the program
BFM#24 b1:OFF
BFM#24 b8:OFF

Local station IP address

10.97.85.222 (0A.61.55.DEH)

BFM#106 to 108

Send frame setting

Ethernet (V2.0)

BFM#24 b5:OFF

TCP Existence confirmation setting

Use the Ping

BFM#24 b4:OFF

[Open settings]
Setting name

6 - 14

Settings in FX Configurator-EN-L (No.1)

Settings in the program

protocol

TCP

BFM#32 b8:OFF

Open system

Active

BFM#32 b14,b15:00

Fixed buffer

Sending

BFM#32 b0:OFF

Fixed buffer communication

Procedure exist

BFM#32 b9:OFF

Paring open

No pairs

BFM#32 b7:OFF

Existence confirmation

No confirm

BFM#32 b1:OFF

Local station Port No.[Decimal]

4096

BFM#40

Destination IP address

10.97.85.223 (0A.61.55.DFH)

BFM#41,42

Destination Port No.[Decimal]

8192

BFM#43

6 - 14

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F

(b) Receive program (FX3U-2nd station)
1) Connection No. 1 is used to process the fixed buffer receiving in the main
program.
2) The unit number specified at the sequence program and
FX Configurator-EN-L is 0.
3) Make Operational Settings in the following manner.
Communication data code : Binary code (BFM#24 b1 : OFF)
Initial timing
: Always wait for OPEN (Communications
possible at STOP time) (BFM#24 b8 : ON)
IP address
: 10.97.85.223 (0A.61.55.DFH)
(BFM#106 to 107)
4) Adjust Open settings in the following manner.
Protocol
: TCP (BFM#32 b8 : OFF)
Open system
: Fullpassive (BFM#32 b14, b15 : 10H)
Fixed buffer
: Receive (BFM#32 b0 : ON)
Fixed buffer communication procedure
: Procedure exist (BFM#32 b9 : OFF)
Pairing open
: Disable (BFM#32 b7 : OFF)
Existence confirmation
: No confirm (BFM#32 b1 : OFF)
Connection No.1 Local station Port No.
: 8192 (BFM#40) (For use in main program)
5) Fixed buffer No. 1 receive data : Stored in D1000 to D1031
6) Fixed buffer No. 1 receive status : D100
[Operational settings]
Setting name
Communication data code setting

Settings in FX Configurator-EN-L
Binary code
Always wait for OPEN

Initial timing

(Communications impossible at STOP time)

Settings in the program
BFM#24 b1:OFF
BFM#24 b8:ON

Local station IP address

10.97.85.223 (0A.61.55.DFH)

BFM#106 to 108

Send frame setting

Ethernet (V2.0)

BFM#24 b5:OFF

TCP Existence confirmation setting

Use the Ping

BFM#24 b4:OFF

[Open settings]
Setting name
protocol

Settings in FX Configurator-EN-L (No.2)

Settings in the program

TCP

BFM#32 b8:OFF

Open system

Fullpassive

BFM#32 b14,b15:10

Fixed buffer

Receive

BFM#32 b0:ON

Fixed buffer communication

Procedure exist

BFM#32 b9:OFF

Paring open

No pairs

BFM#32 b7:OFF

Existence confirmation

No confirm

BFM#32 b1:OFF

Local station Port No.[Decimal]

8192

BFM#40

Destination IP address

10.97.85.222 (0A.61.55.DEH)

BFM#41,42

Destination Port No.[Decimal]

4096

BFM#43

POINT
Make sure to have sufficient device memory according to the maximum data
length sent in order to prevent device areas used for other purposes from being
overwritten by the received data.

6 - 15

6 - 15

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(2) Outline of the program example
(a) Send program (Ethernet module-1st station)
1) After setting each parameter with FX Configurator-EN-L or a sequence
program and writing to the Ethernet module, select re-initial, power ON
the module again, or confirm that the initial processing is completed via
buffer memory operations.
2) Perform open processing (Active open) of connection No. 1. (*1)
3) Communicate with the PLC using fixed buffer communication
(procedure exist sending).
4) After sending is complete, perform close processing of connection
No. 1. (*1)
*1 Use the program example described in Subsection 5.6.1, "Active open
processing/close processing" for the sequence program that executes
the open processing/close processing.
(b) Receive program (Ethernet module -2nd station)
1) After setting each parameter with FX Configurator-EN-L or a sequence
program and writing to the Ethernet module, select re-initial, power ON
the module again, or confirm that the initial processing is
completed via buffer memory operations.
If the initial processing is normally completed, connection No. 1 wait for
an Active open request from the external device.
2) Transfer data from the external device using fixed buffer communication
(procedure exist sending).
3) The data received by the corresponding fixed buffer data area in the
Ethernet module is read to the PLC.

6 - 16

6 - 16

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(Send program)

Open processing program

(See Subsection 5.6.1)

• Program example for the unit No. 0
* <>
M8000

* <>
U0\
X002
M300
M307
G1602
[=
H5
Send
Initial
HUB
OPEN
instruction completed connection
instruction/status
completed

U0\
G28

[MOV

M201

K4M300 )]
Initial
completed

Transmission
M202 abnormally completed

]

(M200
)
Send
instruction
(Self-holding)

Transmission
normally
completed

M200
[MOVP

K32

Send
instruction
(Self-holding)

U0\
G1664
]
Number of
send words
in the fixed
buffer No.1

U0\
G1665
[BMOVP D1000
K32
Head of
Fixed
send data buffer No.1

[MOVP

[MOV

H1

U0\
G1610
Send
request/
status

]

U0\
G1610
]
Send
request/
status

D101
]
Value of
BFM#1610

D101.2
Value of
BFM
#1610

(M201
)
Transmission
normally
completed

Normal completion
processing

D101.3
Value of
BFM
#1610

(M202
)
Transmission
abnormally
completed

Abnormal completion
processing

[END

6 - 17

]

6 - 17

6

FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)

MELSEC-F
(Receive program)
• Program example for the unit No. 0
* <>
* 
D100

* 
]
>
]
>
]

* 
[INCP
D102
]
Receive abnormal processing

]

User applications are described at the area enclosed with

]

]

.

6 - 18

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7 FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)
This chapter explains how the PLC and external device communicate using the fixed
buffers (with the no procedure control method) via the Ethernet module.

POINT
The following points describe the difference from the "Procedure exist" using fixed
buffer communication:
1)

It is possible to send and receive data which match the message format of the
external device.
At data sending, subheader, data length, etc. are not included in the
application data field of a message; only the data in the fixed buffer is sent.
Upon data reception, all the data in the message excluding the header is
stored in the fixed buffer.

2)

A response to data receiving is not sent.

3)

Communication is performed using binary code regardless of the
communication data code settings (see Section 4.6, "Operational Settings").
The maximum application data area is 2046 bytes per communication.

4)
5)

The applicable connection is dedicated to the no procedure fixed buffer
communication.
As with the procedure fixed buffer communication, and communication using
MC protocol cannot be performed at the same time as the no procedure fixed
buffer communication.

7.1 Control Method
The following explains how communication is performed using the fixed buffers and
the no procedure control method.
In communication using the fixed buffers, data transmission from the PLC and the
external device is executed using the no procedure control method.
(1) The data flow during communication is as follows.
(For sending)
TO instruction
(Sending request)

FX3U
main
unit

FROM instruction
(Transmission complete)

Fixed buffer

(For receiving)

No.1
No.2

External
device

FROM instruction
(Reading the received data)
TO instruction
(Reception complete)

7-1

7-1

7

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(2) Data can be communicated with the following external devices.
• Device on the Ethernet to which the Ethernet module is connected.
• Devices connected with the router relay function (see Section 5.3)
As shown in the diagram below, when using each fixed buffer (No. 1, No. 2), the
destination devices and usage conditions (for sending/receiving, procedure exist/
no procedure, etc.) should be set when the connection via the Ethernet module is
opened to fix the external device for each buffer.
(a) At TCP/IP communication
It is allowed to change external devices only when the open completion
signal of the applicable connection is off.
(b) At UDP/IP communication
External devices can be changed regardless of the status of the applicable
connection.
("Destination IP address" and "Destination Port No." in the communication
address setting area can be changed. However, "Local station Port No."
cannot be changed.)
When changing external devices, do not use the "Pairing open" and
"Existence confirmation" functions.
Fixed buffer No. 1
Fixed buffer No. 2

For sending to external
device 1
For receiving from external
device 1

External device 1

POINT
The connections for which no procedure is selected are dedicated to the fixed
buffer sending or receiving after the completion of open processing.

7

7-2

7-2

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(3) At data sending/receiving, the Ethernet module processes the following.
1) When sending data
The fixed buffer communication transmission request (writing "0001H " in
BFM#1610, #1611) allows the fixed buffer data stored in the fixed buffer
data area (BFM#1664 to #3711) to be sent to the specified external
device (BFM#40 to #53). (*1)
2) When receiving data
The Ethernet module processes the received data if it is received from an
external device set in the communication setting area that corresponds to
fixed buffer No. n. (*1)
Also, when the Ethernet module stores the received data in the
corresponding fixed buffer in the receive processing, it updates the
destination IP address and destination port No. in the corresponding
fixed buffer connection information area (BFM#120 to #139)
If data is received from an external device not set in the connection
information area of the buffer memory, the Ethernet module ignores the
received data.
*1 In case of TCP/IP Unpassive open, data is communicated with an
external device stored in the connection information area of the buffer
memory.

7-3

7-3

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7.2 Sending Control Method
This section explains the control method when data is sent from the Ethernet module
to an external device using fixed buffer No. 1 and the area corresponding to
connection No. 1 as an example.
• Program example for the unit No. 0
* <>
M8000
[MOV

U0\
G28

* <>
X002

M300

M307
[=

Send
Initial
HUB
instruction completed connection
completed
M200

U0\
G1602
H5
OPEN
instruction/status

M201
]

Transmission
M202 abnormally completed

Transmission
normally
completed
[MOVP

K32

Send instruction
(Self-holding)

K4M300 ]
Initial
completed

(M200
)
Send
instruction
(Self-holding)
U0\
G1664
]
Number of
send bytes
in the fixed
buffer No.1

U0\
G1665
[BMOVP D1000
K16
Head of
Fixed
send data buffer No.1
[MOVP

[MOV

H1

U0\
G1610
Send
request/
status

]

U0\
G1610
]
Send
request/
status
D101
]
Value of
BFM#1610

D101.2
Value of
BFM#1610

(M201
)
Transmission
normally
completed

D101.3
Value of
BFM#1610

(M202
)
Transmission
abnormally
completed
[END

7-4

]

7-4

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
Initial
Open
Write
processing Processing sent data
Initial processing normal
completion
BFM#27=0001H

Response
receiving

Data sending

1)

HUB connection is signal
BFM#28 b7

2)

OPEN/CLOSE instruction status
BFM#1602=0005H

3)
4)

Write sent byte count
and sent data to BFM

TO instruction

7)

5)
Fixed buffer send instruction
and send completion
BFM#1610

Data receiving

W
0001H

R
0002H

R
0004H (Success)/0008H (Failure)

ACK
(only TCP)
6)

1) Confirm normal completion of the initial processing.
2) Confirm that the Ethernet module is connected to the hub.
(BFM#28 b7:ON)
3) Confirm the normal completion of the open processing for connection No. 1.
4) Write the byte count for send data and the send data to the fixed buffer
data area (BFM#1664 to #2687) by TO instruction.
5) Write "0001H" in the fixed buffer transmission request (BFM#1610).
6) Only the size of the send data in the fixed buffer (No. 1) designated by
the send data length is sent to the designated external device.
The value of BFM#1610 becomes "0002H ".
7) The Ethernet module terminates the data transmission.
At normal completion
• Fixed buffer transmission results (BFM#1610)

: 0004H

At abnormal completion
• Fixed buffer transmission results (BFM#1610)

: 0008H

If the data transmission is abnormally completed, rewrite "0001H" in
BFM#1610 and execute the send processing again.

POINT
The following precaution should be observed when communicating using UDP/IP:
• When the Ethernet module's internal processing is normally completed, data
send processing ends even if the communication line between the PLC and an
external device is disconnected because of cable disconnection, etc. It is
recommended to send/receive data using a user defined communication
procedure.

7-5

7-5

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7.3 Receiving Control Method
This section explains the control method when the Ethernet module receives data
from an external device.

7.3.1 Receive processing with the main program
This section explains the receiving process to be performed with the main program,
using an example in which the fixed buffer No. 2 and the area corresponding to
connection No. 2.
• Program example for the unit No. 0
* <>

M8000
[MOV

U0\
G1611

D100

]

Receiving
Receiving
instruction/status status

[=

D100

H1

]

[MOV

Receiving
status

U0\
G2688

D101

Received
data count

Received
data count

]

* 
[ADD

D101

H1

Received
data count

D101

]

Received
data count

* 
[DIV

D101

H2

Received
data count

[BMOV

U0\
G2689

D103

]

Received
word count

D1000

D103

]

Fixed buffer Receive data Received
No.2
storage head word count

[MOV

H2

U0\
G1611

]

Receiving
instruction/
status

[=

D100

H8

]

[INCP

Receiving
status

D102

[END
User applications are described at the area enclosed with

7-6

]

Receive
abnormal
processing

]

.

7-6

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F

Data
receiving
Read the word count
for the received data
and receive data

FROM
instruction

2)

Notice the receive status
and receive completion
of the fixed buffer
BFM#1611

3)

W
0002H

R

4) 0004H(Success)

/0008H(Error issued)

ACK(only in TCP)

Data receiving

1)

R
BFM#1611=0001H

1) Upon receiving data from the designated external device (set in the open
processing), the Ethernet module processes the following.
• Stores the received data to the fixed buffer (No. 2) area.
(Area beginning from the head address of the target fixed buffer + 1)
• Stores the data length to the head address area of the target fixed
address (*1)
• Fixed buffer communication receive results (BFM#1611) : 0001H
• Fixed buffer receive status signal (BFM#20485 b1)
: ON
*1 The received data length is expressed by a byte count.
When an odd number of data bytes is received, the last byte of
received data is stored at the lower byte of the last data storage area.
(The higher byte becomes a non-constant value.)
2) Execute the FROM instruction to read out the receive byte length and
receive data to the PLC.
3) Execute the TO instruction to write "0002H" in the fixed buffer
communication receive results (BFM#1611).
4) Result of the receiving processing is indicated.

POINT
(1) The destination setting (see Section 5.5) for a connection whose parameters
are set in FX Configurator-EN-L becomes valid when the open completion
signal (BFM#20480 corresponding bit) of the Ethernet module switches from
off to on.
(2) When data is received and the data in the buffer memory's fixed buffer is set,
BFM #1610, #1611 is set to "0001H".
(3) At abnormal data receiving, each buffer memory status becomes as follows.
• Fixed buffer receive completion signal (BFM#20485 b1) remains off.
• Fixed buffer communication receive results (BFM#1611): 0008H
• Data is not stored in the fixed buffer (No.2) area.

7-7

7-7

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7.4 Data Format
When communicating between the Ethernet module and an external device, the data
format explained below is used.
The communication data consists of a "header" and "application data" as shown
below.
Header

Application data

(1) Header
The header for TCP/IP or UDP/IP is used. In case of the Ethernet module, the
Ethernet module adds and deletes the header. Thus, the user does not need to
set it.
(Details of the size of the header section)
1) In case of TCP/IP

Ethernet
14 bytes

IP
20 bytes

TCP
20 bytes

2) In case of UDP/IP

IP
20 bytes

Ethernet
14 bytes

UDP
8 bytes

(2) Application Data
The data code in the application data is expressed in binary code.
Communication is performed using binary code, regardless of the set
communication data (see Section 4.6).
Text (command)

Maximum of 2046 bytes

NOTE
The subheader and data length that are added for communications using the fixed
buffers in the procedure exist control method are not present for communications in
the no procedure control method. All data is treated as valid text.

7-8

7-8

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7.5 Programming
This section explains the programming method when the Ethernet module
communicates with an external device using fixed buffers and the no-procedure
control method.

7.5.1 Precautions when creating programs
(1) In order to communicate using the fixed buffers, the initial processing and the
connection open processing must be completed.
(2) The contents of the parameter settings have been loaded into the Ethernet
module when the Ethernet module open completion signal (BFM#20480
corresponding bit) switches from off to on.
(3) The data length (byte count) is established using the instruction for no procedure
communication.
If the send data length exceeds this range at data sending, a communication
error occurs and the data is not be sent.
(4) Reading or writing to the buffer memory using fixed buffer communication.
• When sending data
Write the send data to the buffer memory (BFM#1664 to #3711).
Write "0001H" in BFM#1610, #1611 before sending the data.
• When receiving data
Check that data has been received (BFM#1610, #1611: "0001H") and read out
the received data (BFM#1664 to #3711) to the PLC.
(5) The following should be observed when using a connection opened by UDP.
• External devices can be switched by modifying the setting values in the
communication address setting area of the communication parameter setting
area before sending/receiving data. Thus, data can be sent to multiple external
devices sequentially. When sending/receiving, make sure to switch between
external devices properly so that no communication problems occur.
(6) Message data length is not included in a packet when communicating with the no
procedure.
The Ethernet module stores the size of the received message (packet) in the
receive data length storage area and turns on the fixed buffer receiving status
signal (BFM#20485 corresponding bit).
It is recommended to employ a check system, such as including the data length
and data type code in the application data of a message, so that the byte count
and data type in the application data can be identified by the receiving side.

7-9

7-9

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
7.5.2 Fixed buffer communication program example (with the no procedure control method)
This section explains the programming method in order to communication data (through
the no procedure control method) with an external device using the fixed buffers.

FX3U-1st station

FX3U-2nd station

(1) Execution environment for the program example
(a) Send program (FX3U-1st station)
1) Connection No. 1 is used for fixed buffer sending.
2) The communication parameters settings are assumed to have been set
as described in Subsection 5.6.1, "Active open processing/close
processing" except the "Fixed buffer communication" parameter.
(see the table below)
3) Fixed buffer No. 1 send data
: Stored in D1000 to D1031
4) Fixed buffer No. 1 send Send instruction complete device
: M201
5) Fixed buffer No. 1 send Send instruction abnormal complete device
: M202
6) Fixed buffer No. 1 send Send instruction complete status
: D101
[Operational settings]
Setting name
Communication data code setting

Settings in FX Configurator-EN-L
Binary code
Do not wait for OPEN

Initial timing

(Communications impossible at STOP time)

Settings in the program
BFM#24 b1:OFF
BFM#24 b8:OFF

Local station IP address

10.97.85.222 (0A.61.55.DEH)

BFM#106 to 108

Send frame setting

Ethernet (V2.0)

BFM#24 b5:OFF

TCP Existence confirmation setting

Use the Ping

BFM#24 b4:OFF

[Open settings]
Setting name

7 - 10

Settings in FX Configurator-EN-L (No.1)

Settings in the program

protocol

TCP

BFM#32 b8:OFF

Open system

Active

BFM#32 b14,b15:00

Fixed buffer

Sending

BFM#32 b0:OFF

Fixed buffer communication

No procedure

BFM#32 b9:ON

Paring open

No pairs

BFM#32 b7:OFF

Existence confirmation

No confirm

BFM#32 b1:OFF

Local station Port No.[Decimal]

4096

BFM#40

Destination IP address

10.97.85.223 (0A.61.55.DFH)

BFM#41,42

Destination Port No.[Decimal]

8192

BFM#43

7 - 10

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(b) Receive program (FX3U -2nd station)
1) Connection No. 2 is used to process the fixed buffer receiving.
2) The unit number specified at the sequence program and
FX Configurator-EN-L is 0.
3) Make Operation settings in the following manner.
Communication data code : Binary code
Initial timing
: Do not wait for OPEN (Communications
impossible at STOP time)
Local station IP address : 10.97.85.223 (0A.61.55.DFH)
4) Adjust open settings in the following manner.
Protocol
: TCP
Open system
: Fullpassive
Fixed buffer
: Receive
Fixed buffer communication procedure
: No procedure exist (BFM#33 b9 : ON)
Pairing open
: Disable (BFM#33 b7 : OFF)
Existence confirmation
: No confirm (BFM#33 b1 : OFF)
Local station Port No.
: 8192 (BFM#47)
5) Fixed buffer No.1 receive data.
: Stored in D1000 to D1031
6) Fixed buffer No.1 receive instruction complete status.
: D100
[Operational settings]
Setting name
Communication data code setting

Settings in FX Configurator-EN-L
Binary code
Always wait for OPEN

Initial timing

(Communications impossible at STOP time)

Settings in the program
BFM#24 b1:OFF
BFM#24 b8:ON

Local station IP address

10.97.85.223 (0A.61.55.DFH)

BFM#106 to 108

Send frame setting

Ethernet (V2.0)

BFM#24 b5:OFF

TCP Existence confirmation setting

Use the Ping

BFM#24 b4:OFF

[Open setting]
Setting name
protocol

Settings in FX Configurator-EN-L (No.2)

Settings in the program

TCP

BFM#33 b8:OFF

Open system

Fullpassive

BFM#33 b14,b15:10

Fixed buffer

Receive

BFM#33 b0:ON

Fixed buffer communication

No procedure

BFM#33 b9:ON

Paring open

No pairs

BFM#33 b7:OFF

Existence confirmation

No confirm

BFM#33 b1:OFF

Local station Port No.[Decimal]

8192

BFM#47

Destination IP address

10.97.85.222 (0A.61.55.DEH)

BFM#48,49

Destination Port No.[Decimal]

4096

BFM#50

POINT
Make sure to have sufficient device memory according to the maximum data
length sent in order to prevent device areas used for other purposes from being
overwritten by the received data.

7 - 11

7 - 11

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(2) Outline of the program example
(a) Send program (FX3U-1st station)
1) After setting each parameter with FX Configurator-EN-L or a sequence
program and writing to the Ethernet module, power ON the module
again, or confirm that the initial processing is completed via buffer
memory operations.
2) Perform open processing (Active open) for connection No. 1. (*1)
3) Communicate data from the PLC using fixed buffer communication (no
procedure sending).
4) After data sending is complete, perform close processing for
connection No. 1. (*1)
*1 Use the program example described in Subsection 5.6.1, "Active open
processing/close processing" for the sequence program that executes
the open processing/close processing.
Make sure to change the "Fixed buffer communication" setting from
"Procedure exist" to "No procedure".
(b) Receive program (FX3U-2nd station)
1) After setting each parameter with FX Configurator-EN-L or a sequence
program and writing to the Ethernet module select re-initial and power
ON the module again, or confirm that the initial processing is completed
via buffer memory operations.
If the initial processing is normally completed, connection No. 2 waits for
an Active open request from the external device.
2) Transfer data from the external device using fixed buffer communication
(no procedure sending).
3) The data received by the corresponding fixed buffer data area in the
Ethernet module is read to the PLC.

7 - 12

7 - 12

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(Send program)
• Program example for the unit No. 0
* <>
M8000
[MOV

U0\
G28

* <>
X002

M300

M307
[=

Send
Initial
HUB
instruction completed connection
completed
M200

U0\
G1602
H5
OPEN
instruction/status

M201
]

Transmission
M202 abnormally completed

Transmission
normally
completed
[MOVP

K32

Send instruction
(Self-holding)

K4M300 ]
Initial
completed

(M200
)
Send
instruction
(Self-holding)
U0\
G1664
]
Number of
send bytes
in the fixed
buffer No.1

U0\
G1665
[BMOVP D1000
K16
Head of
Fixed
send data buffer No.1
[MOVP

[MOV

H1

U0\
G1610
Send
request/
status

]

U0\
G1610
]
Send
request/
status
D101
]
Value of
BFM#1610

D101.2
Value of
BFM#1610

(M201
)
Transmission
normally
completed

D101.3
Value of
BFM#1610

(M202
)
Transmission
abnormally
completed
[END

7 - 13

]

7 - 13

7

FIXED BUFFER COMMUNICATION (WITH THE NO PROCEDURE
CONTROL METHOD)

MELSEC-F
(Receive program)
• Program example for the unit No. 0
* <>

M8000
[MOV

U0\
G1611

D100

]

Receiving
Receiving
instruction/status status

[=

D100

H1

]

[MOV

Receiving
status

U0\
G2688

D101

Received
data count

Received
data count

]

* 
[ADD

D101

H1

Received
data count

D101

]

Received
data count

* 
[DIV

D101

H2

Received
data count

[BMOV

U0\
G2689

D103

]

Received
word count

D1000

D103

]

Fixed buffer Receive data Received
No.2
storage head word count

[MOV

H2

U0\
G1611

]

Receiving
instruction/
status

[=

D100

H8

]

[INCP

Receiving
status

D102

[END
User applications are described at the area enclosed with

7 - 14

]

Receive
abnormal
processing

]

.

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8 COMMUNICATION USING MC PROTOCOL
This chapter gives an overview of the MC protocol.

NOTE
The frame type of MC protocol (data communication messages) used by the
external device to access the PLC via this product is equivalent to A compatible 1E
frame.

IP

(14 bytes) (20 bytes)

TCP
/
UDP

Text (Command)
PC ACPU
Head device
No. monitoring
timer
L

00H

FFH

0AH

H

L

Number of
device points

Ethernet

Header

Subheader

(Example)

H

00H 64H 00H 00H 00H 20H 40H

0CH

00H

(Command message for the A compatible 1E frame)

8.1 Data Communication Function
The MC protocol is the abbreviated name of the MELSEC protocol that is a
communication system for the PLCs. Using this protocol, the external devices can
read or write device data from/to the PLC via the Ethernet module.
Any external devices on which application programs can be installed and which can
send and receive data in accordance with the MELSEC PLC protocol can access the
PLC using MC Protocol.

8.1.1 Accessing the PLC using MC protocol
This section explains the main functions for accessing the PLC using MC protocol.
On the PLC side, the Ethernet module sends and receives data based on the
instructions (protocol) from the external devices, so the PLC side does not require
sequence programs for data communication.

(1) Data read/write
This function reads/writes data from/to the PLC device memory to which the
Ethernet module is connected.
By reading and writing data, the PLC operation monitoring, dzata analysis and
production management can be performed on the external device side.

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(2) Remote control of the PLC
This function executes remote RUN/STOP operations.
Remote operations of the PLC can be performed from the external device side.
Send frame
Communication
using MC protocol

*1

Communication data code

A compatible 1E
ASCII code or binary code *1
frame.

Function
Device memory read/
write

Batch read/write in bit/
word units

Remote control of the
PLC

Remote RUN
Remote STOP

Time required for communication in binary code is shorter because the amount of communication data is
approximately a half of what is required for communication in ASCII code data.

8.1.2 How to Read the Control Procedures of the MC Protocol
This section explains the control procedures when an external device accesses the
PLC using MC protocol.

(1) Transmission of command messages
Data communication through the MC protocol is performed using half-duplex
communication.
When accessing the PLC, send the next command message after receiving a
response message from the PLC side for the previous command message
transmission.
External device side

(Command message)

PLC side

(Command message)
(Response message)

(Response message)

(2) When a normal completion response message to a command
message cannot be received

8

1)
2)

8-2

If an abnormal completion response message is received
Handle the case according to the error code in the response message.
If the response message cannot be received or nothing can be received
Send the command message again after the monitoring time of the response
monitor timer.
* Modify the value of the monitoring time as needed.

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8.1.3 Access Timing on the PLC Side
The following diagram illustrates the access timing on the PLC side when an external
device accesses the PLC via the Ethernet module.
External device
Read/write command
(command)

Reply to the

(*1)

(*1) command (response)

ACK
1)

4)

2)

3)

ACK

Ethernet module

PLC

STEP 0

END

STEP 0

END processing

END

END processing

STEP 0

END

STEP 0

END

END processing

Processing of the command from the external device

1) A command message is transmitted from the external device to the PLC
side.
2) Upon receiving a command message from the external device, the
Ethernet module on the PLC side sends a data read/write request to the
PLC according to the content of the command.
3) The PLC reads/writes data according to the request from the external
device at the time of executing the sequence program's END instruction,
and passes the processing result to the Ethernet module.
4) Upon receiving the processing result from the PLC, the Ethernet module
sends a response message including the processing result to the
external device that originated the request.
*1 The ACK response shown in the diagram is sent/received between the
Ethernet module and the external device respectively when the access
via the Ethernet module is performed by TCP/IP communication.
It is different from the response to the processing requested by the
external device in the command message (the processing result).
When access via the Ethernet module is performed by UDP/IP, the ACK
response indicated by *1 is not sent.

NOTE
Regarding the scan time of the PLC
1) While the PLC is performed by required command, access command to the
Ethernet module and the PLC is processed during every END processing.
(The scan time becomes longer according to the amount of time it takes to
process the command.)
2) When multiple external devices issue access requests to the Ethernet module at
the same time, the processing requested from the external devices may have to
wait for multiple END processing executions depending on the timing of the
requests.

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8.1.4 PLC setting for performing data communication
Data communication via MC protocol is enabled by adjusting the following settings
using FX Configurator-EN-L and writing the parameters to the Ethernet module.
1)

Operational settings (see Section 4.6.)

2)

Initial settings (see Section 5.2)

3)

Open settings (see Subsection 5.5.2)

8.1.5 Precautions on Data Communication
This section explains some precautions that should be observed when performing
data communication between an external device and the Ethernet module.

(1) Precautions that should be observed when performing data
communication via the Ethernet module
(a) Perform read/write only when the buffer memory status of Ethernet module
is the following.
If the initial normal completion signal (BFM# 27 [0001H]) and the open
completion signal (BFM#20480 corresponding bit) of the used connection is
ON (open completion status), it is possible to communicate from an external
device using MC protocol without regard to the existence of a sequence
program. (Only connections No. 3 and 4 are available in communication
using MC protocol.)
(b) Use the UDP connection set to "Always wit for OPEN (BFM #24 b8: ON)" in
the initial timing setting in the operation settings. Or use the passive open
connection in the case of TCP.
(c) Communication using MC protocol is enabled only when the communication
parameter for an open connection is set to "MC protocol usable" in
"Connection usage" as described in the table in Subsection 5.5.2.
To set this using FX Configurator-EN-L, select the open settings from the
initial screen, and when a protocol is TCP, select [Unpassive(MC)] or
[Fullpassive(MC)] in [Open system].
(d) Replacing the Ethernet module
The Ethernet address (MAC address) differs depending on the device.
When the Ethernet module is replaced due to breakdown, reboot any
external devices also.
Similarly, reboot the Ethernet module even when an external device is
replaced (such as a personal computer).

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MEMO

8-5

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9 WHEN COMMUNICATING DATA USING THE MC PROTOCOL
This chapter explains the message format, how to designate data items in a message
and restrictions for data communication with an Ethernet module using MC protocol
with A compatible 1E frames.

9.1 Message Formats and Control Procedures
This section explains the message format and control procedure for each command
when data communication is performed using A compatible 1E frames.
The MC protocol for the Ethernet module is a subset of A compatible 1E frames.
Both TCP/IP and UDP can be used as lower layer protocol and support both ASCII
code and binary code.

9.1.1 How to read the command reference section
The following explains how to read the message explanation diagrams shown in each
of the command description Sections 9.3 through 9.5.

(1) When an external device reads data from the PLC

Area A

Header
Subheader
Complete code

PLC side

Monitoring
timer

External
device side

Header
Subheader
PC No.

(Command message)

Area B

(Response message)

1) Area A indicates transmission from the external device to the PLC.
2) Area B indicates transmission from the PLC to the external device.
3) The program of the external device is generated so that the data is
transmitted sequentially from left to right. (For example: in case of
area A, data should be sequentially sent from Header to the right.)

9

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(2) When an external device writes data to the PLC

PLC side

Complete code

Area C

Header
Subheader

Monitoring
timer

External
device side

Header
Subheader
PC No.

(Command message)

(Response message)

1) Area C indicates transmission from the external device to the PLC.
2) The program of the external device is generated so that the data is
transmitted sequentially from left to right. (For example: in case of
area C, data should be sequentially sent from Header to the right.)

POINT
When the PLC receives a command message from an external device, it
completes processing of the data in area A/C, then sends a response message
and waits for the next command message (neutral state).

9

9-2

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9.1.2 Message format and control procedure
This section explains the message format and control procedure.

(1) Message format
This section explains the message format for transmission between the Ethernet
module and an external device.
The communication data consists of "header" and "application data" as shown
below.
Header

Application data

(a) Header
The header for TCP/IP or UDP/IP is used. The user does not need to specify
it; the Ethernet module attaches it.
(b) Application data
The application data is largely divided into "subheader" and "text" as shown
below.
The subheader represents command/response and the setting value is
predetermined.
The text contains the request data (command) and response data
(response) for each function and this data is determined by the prescribed
format (for a more detailed description, see sections 9.3 and later).
(c) Format in the application data field
• Communication in ASCII code
Application data
External
device
side
PLC side

Subheader

Text (command)

2 bytes

Differs depending
on function

Differs depending on
function and
normal/abnormal
completion

2 bytes
Subheader

Text (response)

Application data

• Communication in binary code
Differs depending on
function and
normal/abnormal
completion

Application data
External
device
side

PLC side

Subheader

Text (command)

1 byte

Differs depending
on function

1 byte
Subheader

Text (response)

Application data

NOTE
When communicating in the MC protocol, the user does not need to specify a
response for a command from an external device; the Ethernet module generates it
and then responds.

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(2) Control procedure
The following diagrams illustrate the control procedure for communicating with
the MC protocol and the order of data items in the application data field.
The header section shown in the message explanation diagram of this section
corresponds to the portion of the message explanation diagrams indicated in
Subsection 9.3.2 and later.
See Subsection 9.1.3 regarding the content of data items in the message format
and data specification method.
(a) Communication in ASCII code
1) When reading data from the local station PLC at the external device side
External device side

PLC side (Command message)

(Example)

Monitoring
timer

PC No.

Subheader

(Data name)

Header

Text (Command)

The contents and arrangement of the data items in
the text differs according to the function to use.
See the sections explaining functions found in
Subsection 9.3.2 and after for details

H L H - L
0 0
F F 0 0 0 A
30H 30H 46H 46H 30H 30H 30H 41H
Character area A

External device side (Response message)
(Abnormal completion)

(Normal completion)

Text (Response)

H L
8 0 0 0
38H 30H 30H 30H

H L H L
8 0 5 B 1 2 0 0
38H 30H 35H 42H 31H 32H 30H 30H
Character area B

9-4

Complete code

When complete code
5BH is returned

Subheader

Header

Complete code

Subheader

Header

Text (Response)

Abnormal code

PLC side

Exists only when the complete code is "5B."

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2) When writing data to the local station PLC from the external device side
External device side

PLC side (Command message)

Monitoring
timer

PC No.

Subheader

(Data name)

Header

Text (Command)

The contents and arrangement of the data items in
the text differs according to the function to use.
See the sections explaining functions found in
Subsection 9.3.2 and after for details

- L
H L H 0 2 F F 0 0 0 A
30H 32H 46H 46H 30H 30H 30H 41H

(Example)

Character area C

External device side (Response message)

(Normal completion)

(Abnormal completion)
Text (Response)
Complete code

When complete code
5BH is returned

Subheader

Header

Complete code

Header

Subheader

Text (Response)

Abnormal code

PLC side

H L H L
8 2 5 B 1 2 0 0
38H 32H 35H 42H 31H 32H 30H 30H

H L
8 2 0 0
38H 32H 30H 30H

Exists only when the complete code is "5B."

(b) Communication in binary code
1) When reading data from the local station PLC at the external device side
External device side

PLC side (Command message)

Monitoring
timer

PC No.

Subheader

(Data name)

Header

Text (Command)

L

H

0AH

00H

The contents and arrangement of the data items in
the text differs according to the function to use.
See the sections explaining functions found in
Subsection 9.3.2 and after for details

(Example)
00H

FFH

Character area A

PLC side

External device side (Response message)

(Normal completion)

(Abnormal completion)
Complete code

Abnormal code

Header

80H

5BH

12H

When complete code
5BH is returned

00H
Character area B

9-5

Text (Response)
Subheader

80H

Complete code

Subheader

Header

Text (Response)

00H

Exists only when the complete code is "5B."

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2) When writing data to the local station PLC from the external device side
PLC side (Command message)

External device side

Monitoring
timer

PC No.

Subheader

(Data name)

Header

Text (Command)

L

H

0AH

00H

The contents and arrangement of the data items in
the text differs according to the function to use.
See the sections explaining functions found in
Subsection 9.3.2 and after for details

(Example)
02H

FFH

Character area C

PLC side

External device side (Response message)

(Normal completion)

(Abnormal completion)
Text (Response)
Abnormal code

Header

Complete code

00H

Subheader

82H

Complete code

Subheader

Header

Text (Response)

82H

5BH

12H

When complete code
5BH is returned

00H

Exists only when the complete code is "5B."

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9.1.3 Contents of data designation items
This section explains the data items of commands and responses when
communicating using MC protocol.
In the response that is returned by the Ethernet module to an external device, the
data is automatically specified by the Ethernet module; the user does not need to
specify it.

(1) Header
The header for TCP/IP or UDP/IP is used. The user does not need to specify it at
the PLC side; the Ethernet module attaches it.

(2) Subheader
The format of the subheader is configured as follows.
B7

B6

B5

B4

B3

B2

B1

B0

Command/response type
(This differs for each function. For details,
see Section 9.2 and later.)
Command/response flag
For command: 0
For response: 1

(3) PC number
The PC number is fixed at a value of "FFH".
(a) When communicating in binary code, the PC number is expressed in binary
value.
(b) When communicating in ASCII code, the PC number is expressed in
hexadecimal ASCII code.

(4) Monitoring timer
This is a timer for setting the period of time that the Ethernet module should wait
after outputting a read/write request to the PLC until the result is returned.
(a) Specify the value as shown below.
0000H (0):
0001 to FFFFH (1 to 65535)

:
:

Waits infinitely *1
Wait time (in units of 250 ms)

*1 It keeps waiting until a response is returned from the PLC.
(b) For normal data communications, using a value within the setting range of 1
to 40 (0.25 to 10s) is recommended.

(5) Character field (command)
This data contains the Ethernet module commands that indicate functions for
when an external device reads/writes data from/to the target PLC station.
The contents and order of data in the Character field (command) field differ
depending on the function used.
The order of data items for each function is explained in each function's reference
section in Subsection 9.3.2. and later.

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(6) Character field (response)
This data contains data read/processing result when an external device reads/
writes data from/to the target PLC station.
The contents and order of data in the Character field (response) differ depending
on the function used.
The order or data items at normal completion for each function is explained in
each function's reference section in Subsection 9.3.2. and later.

(7) Complete code
The result of processing when an external device reads/writes data from/to the
target PLC station is indicated by the following values.
00H
: Normal completion
Other than 00H : Abnormal completion (50 to 60H)
(a) When communicating in binary code, the complete code is expressed in
binary values.
(b) When communicating in ASCII code, the complete code is expressed in
hexadecimal ASCII code.
(c) When the complete code indicates abnormal completion, check the content
and take an action according to the troubleshooting section of Chapter 11.
When the complete code is 5BH/"5B," the abnormal code data (10 to 18H)
and 00H/"00" are included immediately after.

(8) Abnormal code
This value indicates the nature of the error when the processing result of reading/
writing data from/to the target PLC station by an external device is faulty and the
complete code is 5BH/"5B." (Abnormal code: 10 to 18H)
(a) When communicating in binary code, the abnormal code is expressed in
binary values.
(b) When communicating in ASCII code, the abnormal code is expressed in
hexadecimal ASCII code.
(c) Check the content and take an action according to the troubleshooting
section of Chapter 11.

POINT
The data code (ASCII/binary) when sending/receiving commands and responses
between the Ethernet module and an external device is determined in the
operation settings in FX Configurator-EN-L.
The external device communicating with Ethernet module should send the values
specified in each data item in the commands and responses in the above setting
using the code shown below. Also, it should receive the corresponding values in
the code shown below.
In the explanation hereafter in this section, the values specified in each item in a
command and response are shown in binary values.
(1) Communication in binary code
Unless specifically stated, the value shown in each explanation is sent/
received in the designated order (L to H) since it is in binary.
(2) Communication in ASCII code
Unless specifically stated, the value shown in each explanation is converted
to hexadecimal ASCII code and sent/received in the designated order (H to
L).
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NOTE
The following example shows the designation of the subheader to the monitoring
timer when communicating using MC protocol under the following conditions.
(Designated value)
• Target station

: FX3U/FX3UC series to which FX3U-ENET-L is connected

:

FFH

• Function used

:

Device memory batch read (bit units) :

00H

• Monitoring timer value

:

2500 ms

000AH

:

(1) Format when communicating in binary code
(a) The order when sending a command (external device

Ethernet module)

Application data
Subheader

PC number

Header

(L)
00H

Character field (command)
(Head device number)
(Device name) Number of
(H)
(L)
(L)
(H) device points

Monitoring
timer
(H)

00H
FFH
0AH
(Local station) (2500 ms)

64H

00H

00H

00H

20H

(100)

4DH

(M)

(b) The order when receiving a response (external device

08H
(8 points)

00H

Ethernet module)

Application data
Subheader
Header

80H

Complete
code

00H

Character field (response)
on/off status of the
designated device

10H

(Normal
completion)
M100(ON)
M101(OFF)
M102(ON)
M103(OFF)

9-9

10H

01H

10H

M107(OFF)
M106(ON)
M105(ON)
M104(OFF)

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(2) Format when communicating in ASCII code
(a) The order when sending a command (external device

Ethernet module)

Application data
Subheader

PC number
(H)

Header
"0"
30H

"0"
30H

Monitoring timer

(L)

(H)

"F"
"F"
"0"
46H
46H
30H
(Local station)

"D"
"2"
44H
32H
(M)

"0"
"0"
30H
30H
(2500 ms)

"A"
41H

Application data
Text (command)
(Head device number)

(Device name)
(H)
"4"
34H

(L)

(L)
"0"
30H

(H)
"0"
30H

"0"
30H

"0"
30H

"0"
"0"
30H
30H
(100)

"0"
30H

"6"
36H

(L)
"4"
34H

Number of
device points
(H)
(L)
"0"
"8"
30H
38H
(8 points)

(b) The order when receiving a response (external device

"0"
30H

"0"
30H

Ethernet module)

Application data
Subheader
Header
8
38H

"0"
30H

Text (response)
ON/OFF status of the designated device

Complete
(H)
(L)
"0"
"0"
30H
30H
(Normal
completion)
M100(ON)
M101(OFF)

(H)
"1"
31H

"0"
30H

"0"
30H

"0"
30H

"1"
31H

"1"
31H

(L)
"0"
30H

M107(OFF)
M106(ON)
M102(ON)
M103(OFF)

9 - 10

"1"
31H

M105(ON)
M104(OFF)

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9.1.4 Character area transmission data
This section explains how to transmit the bit device data and word device data
handled in the character areas, as well as the order of transmission when
communicating data between an external device and the PLC by each command.
The transmission data shown in the examples is contained in character area B when
reading, and in character area C when writing, testing.

(1) Data communication using ASCII code
(a) When reading to or writing from a bit device memory
The bit device memory can be read and written in bit units (one device point)
or word units (16 device points).
How data is transmitted in each case is explained below.
1) Bit units (one point)
In case of bit units, the bit device memory is handled from the designated
head device for the number of designated device points sequentially from
the left. They are expressed as "1" (31H) if the device is on or "0" (30H) if
the device is off.
(Example)
Indicating the ON/OFF status of five points from M10
Device
point

Head device

H
4

D

2

0

0

0

0

0

0

0

0

L
A

H
0

L
5

Data

1

0

1

1

0

34 H 44 H 32 H 30 H 30 H 30 H 30 H 30 H 30 H 30 H 30 H 41 H 30 H 35 H 31 H 30 H 31 H 30 H 31 H

Indicates that M14 is ON
Indicates that M13 is OFF
Indicates that M12 is ON
Indicates that M11 is OFF
Indicates that M10 is ON

2) Word units (16 points)
When the bit device memory is handled as word units, each word is
expressed in hexadecimal values in 4-bit units sequentially from the
higher bit.
(Example)
Indicating the ON/OFF status of 32 points from M16
The device point is "02" in 16-point units.
Device
point

Head device

H
4

D

2

0

0

0

0

0

0

0

1

L
0

0

2

Data

A

B

Data

1

2

3

4

C

D

34 H 44 H 32 H 30 H 30 H 30 H 30 H 30 H 30 H 30 H 31 H 30 H 30 H 32 H 41 H 42 H 31 H 32 H 33 H 34 H 43 H 44 H

A

B

1

2

3

4

C

D

B15 B14B13B12 B11B10B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B15B14B13B12 B11B10B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

1: Indicates ON

1 0 1 0 1 0 1 1 0 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 1 1 0 0 1 1 0 1

0: Indicates OFF

M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32

9 - 11

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(b) When reading from or writing to a word device memory
Each word of the word device memory is expressed in hexadecimal values
in 4-bit units sequentially from the higher bit.
(Example)
Indicating the storage contents of data registers D350 and D351

H
4

4

2

0

0

0

0

Data

Device
point

Head device

0

0

1

5

L
E

H
0

L
2

H
5

6

A

Data

L
B

H
1

7

0

L
F

34 H 34 H 32 H 30 H 30 H 30 H 30 H 30 H 30 H 31 H 35 H 35 H 30 H 32 H 35 H 36 H 41 H 42 H 31 H 37 H 30 H 46 H

5

6

A

B

1

7

0

F

B15 B14B13B12 B11B10B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B15B14B13B12 B11B10B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

1: Indicates ON

0 1 0 1 0 1 1 0 1 0 1 0 1 0 1 1 0 0 0 1 0 1 1 1 0 0 0 0 1 1 1 1

The content of D350 indicates 56ABH
(22187 in decimal)

0: Indicates OFF

The content of D351 indicates 170FH
(5903 in decimal)

POINT
(1) When designating alphabet letters in the character area, use upper case
code.
(2) When data other than an integer value (real number, character string, etc.)
was stored in a word device memory to be read, the stored value is read as an
integer value.
(Example 1)
When the real number (0.75) is stored in D0 and D1, it is read as the
following integer values:
D0 = 0000H, D1 = 3F40H
(Example 2)
When the character string ("12AB") is stored in D2 and D3, it is read as the
following integer values:
D2 = 3231H, D3 = 4241H

9 - 12

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MELSEC-F

(2) Data communication using binary code
(a) When reading to or writing from the bit device memory
The bit device memory can be read and written in bit units (one device point)
or word units (16 device points).
How data is transmitted in each case is explained below.
1) Bit units (one point)
In case of bit units, four bits designate one point and the bit device
memory is handled from the designated head device for the number of
designated device points sequentially from the left. They are expressed
as "1" if the device is ON or "0" if the device is OFF.
(Example)
Indicating the ON/OFF status of five points from M10

L

H

Device point

Head
device

Data

0AH 00 H 00 H 00 H 20 H 40 H 05 H 10 H 10 H 10 H

Expressed by dummy when the point is
an odd number
Indicates that M14 is ON
Indicates that M13 is OFF
Indicates that M12 is ON
Indicates that M11 is OFF
Indicates that M10 is ON

2) Word units (16 points)
In case of word units, one bit designates one point and the bit device
memory is handled from the designated head device for the number of
designated device points sequentially from the left. They are expressed
in 16-point units in the order, low byte (L: bits 0 to 7) to high byte (H: bits
8 to 15).
(Example)
Indicating the ON/OFF status of 32 points from M16
The device point is "02" in 16-point units.
Device point

Data

Data

L

L

H

AB12H

H

34CD H

02 H 12 H ABH CDH 34 H

1

2

A

B

C

D

3

4

B7 B6 B5 B4 B3 B2 B1 B0 B15 B14 B13 B12 B11B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B15 B14 B13 B12 B11 B10 B9 B8

0 0 0 1 0 0 1 0 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 1 0 0 1 1 0 1 0 0

1: Indicates ON
0: Indicates OFF

M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M M
23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24 39 38 37 36 35 34 33 32 47 46 45 44 43 42 41 40
Head

9 - 13

End

9 - 13

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(b) Reading from or writing to a word device memory
Each word of a word device memory is designated by 16 bits and the
designated number of points from the designated head device are
sequentially expressed in one-point units in the order, low byte (L: bits 0 to 7)
to high byte (H: bits 8 to 15).
(Example)
Indicating the storage contents of data registers D350 and D351
Device point

Data

Data

L

L

H

56AB H

H

170FH

02 H ABH 56 H 0FH 17 H

(L)
(H)
(L)
(H)

A

B

5

6

0

F

1

7

B7 B6 B5 B4 B3 B2 B1 B0 B15 B14 B13 B12 B11B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B15 B14 B13 B12 B11 B10 B9 B8

1 0 1 0 1 0 1 1 0 1 0 1 0 1 1 0 0 0 0 0 1 1 1 1 0 0 1 1 0 1 1 1

5

6

A

B

1

7

0

1: Indicates ON
0: Indicates OFF

F

B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

0 1 0 1 0 1 1 0 1 0 1 0 1 0 1 1 0 0 0 1 0 1 1 1 0 0 0 0 1 1 1 1

The content of D350 indicates 56ABH
(22187 in decimal)

The content of D351 indicates 170FH
(5903 in decimal)

POINT
(1) When data other than an integer value (real number, character string, etc.)
was stored in a word device memory to be read, the module reads the stored
value as an integer value.
(Example 1)
When the real number (0.75) is stored in D0 and D1, it is read as the
following integer values:
D0 = 0000H, D1 = 3F40H
(Example 2)
When the character string ("12AB") is stored in D2 and D3, it is read as the
following integer values:
D2 = 3231H, D3 = 4241H

9 - 14

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MELSEC-F

9.2 List of Commands and Functions for The MC protocol
The following table lists the commands and functions when an external device
accesses the PLC.
Command/response type

Processing

Function
Bit units
Batch read

Batch write
Device
memory

PLC control

Loop test

*1

Word units

01H

Bit units

02H

Word units

03H

Bit units
Test
(Random write)

00H

Word units

04H

05H

Reads bit devices (X, Y, M, S, T, C) in 1-point units.
Reads bit devices (X, Y, M, S, T, C ) in 16-point units.

Number of points
processed per
communication
256 points
32 words (512 points)

Reads word devices (D, R, T, C ) in 1-point units. (*1)

64 points

Writes to bit devices (X, Y, M, S, T, C ) in 1-point units.

160 points

Writes to bit devices (X, Y, M, S, T, C ) in 16-point units.

10 words (160 points)

Writes to word devices (D, R, T, C ) in 1-point units.

64 points

Sets/resets bit devices (X, Y, M, S, T, C) in 1-point units
by arbitrarily designating the devices and device number.

80 points

Sets/resets bit devices (X, Y, M, S, T, C) in 16-point units
by arbitrarily designating the devices and device number.

10 words (160 points)

Sets/resets word devices (D, R, T, C) in 1-point units by
arbitrarily designating the devices and device numbers.
Not applicable for 32 bit devices from C200 to C255.

Remote RUN

13H

Remote STOP

14H

PLC model name read

15H

Reads PLC model name code.

16H

Returns the character received from the other node to
that node with the data as it is.

10 points

Requests the remote RUN/STOP to PLC.

254 bytes

When the double word data is read using the user program, etc., read out the 32bit data at once.

9 - 15

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MELSEC-F

9.3 Device Memory Read/Write
This section explains the designations in the control procedure when reading from
and writing to the device memory by providing an example.

9.3.1 Commands and device range
(1) Commands used for reading from and writing to the device memory
Item

Command/response type

Bit units

00H

Word units

01H

Batch read

Bit units

02H

Word units

03H

Batch write

Bit units

04H

Test
(random write)
Word units

9 - 16

05H

Processing

Number of points processed per
communication

Reads bit devices (X, Y, M, S, T, C) in 1-point units.

256 points

Reads bit devices (X, Y, M, S, T, C) in 16-point units.

32 words (512 points)

Reads word devices (D, R, T, C) in 1-point units.

64 points

Writes to bit devices (X, Y, M, S, T, C ) in 1-point
units.

160 points

Writes to bit devices (X, Y, M. S, T, C) in 16-point
units.

10 words (160 points)

Writes to word devices (D, R, T, C ) in 1-point units.

64 points

Sets/resets bit devices (X, Y, M, S, T, C ) in 1-point
units by arbitrarily designating the devices and
device number.

80 points

Sets/resets bit devices (X, Y, M, S, T, C ) in 16-point
units by arbitrarily designating the devices and
device numbers.

10 words (160 points)

Writes to word devices (D, R, T, C, etc.) in 1-point
units by arbitrarily designating the devices and
device numbers.
Not applicable for 32 bit devices from C200 to C255.

10 points

9 - 16

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MELSEC-F

(2) Designation method and accessible range of devices.
(a) In device read/write, each device is set by a device code and number as
shown in the diagram below.
B15

B0 B31

to

to

B0

Device number (Set in hexadecimal)

Device code

[Example] In case of D100
D100 = 4420 00000064H
Device number (hexadecimal)
Device code

(b) The following table outlines the device codes and numbers.

Device list
Device

Device code

Device range

Data register

D
(44H, 20H)

D0 to D7999

0000 to 1F3FH

D8000 to D8511

1F40 to 213FH

Extension register

R
(52H, 20H)

R0 to R32767

0000 to 7FFFH

Current value

TN
(54H, 4EH)

T0 to T511

0000 to 01FFH

Contact

TS
(54H, 53H)

T0 to T511

0000 to 01FFH

Current value

CN
(43H, 4EH)

C0 to C199

0000 to 00C7H

C200 to C255

00C8 to 00FFH

Contact

CS
(43H, 53H)

C0 to C199

0000 to 00C7H

C200 to C255

00C8 to 00FFH

Timer

Counter

Device number

Input

X
(58H, 20H)

X0 to X377

0000 to 00FFH

Output

Y
(59H, 20H)

Y0 to Y377

0000 to 00FFH

Internal relay

M
(4DH, 20H)

State

S
(53H, 20H)

9 - 17

M0 to M7679

0000 to 1DFFH

M8000 to M8511

1F40 to 213FH

S0 to S4095

0000 to 0FFFH

9 - 17

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MELSEC-F

POINT
(1) Bit devices and word devices are classified according to the following.
Bit devices
: X, Y, M, S, T (contact), C (contact)
Word devices : T (current value), C (current value), D, R
(2) When word units are designated, always make the head device number of a
bit device a multiple of 16 (0, 16... in decimal representation).
For X and Y is expressed in octadecimal, the device numbers that can be
designated are X00, X20, X40,,, or Y00, Y20, Y40,,,.
Also, special M relays M8000 or later can be specified (8000 + multiples of
16).
(3) The special relays (M8000 to M8511) and special registers (D8000 to D8511)
are divided into read only, write only and system use registers.
If writing takes place outside the writing enabled range, a PLC error may
occur.
See the Programming Manual for detailed descriptions of the special relays
and the special registers.

9 - 18

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MELSEC-F

9.3.2 Batch read in bit units (command: 00)
The examples shown in this section explain the command/response format when
batch-reading the bit device memory.
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Reading the on/off status of M100 to M111 of the PLC on which the FX3U-ENET-L is
loaded.

Head device

External device
side
(Example)

L

H

L

-

-

-

-

H

Number of device points

Monitoring
timer

PC No.

(Data name)

Subheader

(1) Communication in binary code

(Data name)
PLC side

Complete code

Subheader

00H FFH 0AH 00H 64H 00H 00H 00H 20H 4DH 0CH 00H
Data for the number
of designed device
points
Characters for the
number of device
points

(Example)
80H 00H 10H 10H 10H 10H 10H 10H

1 0 1 0 1 0 1 0 1 0 1 0
Status

Status

Status

Status

Status

Status

of M101

of M103

of M105

of M107

of M109

of M111

Status

Status

Status

Status

Status

Status

of M100

of M102

of M104

of M106

of M108

of M110

NOTE
Use the designation "00H" when the number of device points is 256 points.

9 - 19

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MELSEC-F

Number of
device points

Head device

(Data name)

PLC side

Complete code

H L H - - L H - - - - - - - - - - L H L
0 0 F F 0 0 0 A 4 D 2 0 0 0 0 0 0 0 6 4 0 C 0 0
30H 30H 46H 46H30H 30H 30H 41H 34H44H 32H 30H 30H 30H 30H 30H 30H 30H 36H 34H 30H 43H 30H 30H
Subheader

(Example)

Monitoring
timer

External device
side

PC No.

(Data name)

Subheader

(2) Communication in ASCII code

Data for the number
of designed device
points
Characters for the
number of device
points

H L H L H L H L H L H L H L
8 0 0 0 1 0 0 0 1 0 1 1 0 0 0 0
38H 30H 30H 30H 31H30H 30H 30H 31H 30H 31H 31H 30H 30H 30H 30H

(Example)

8 0 0 0 1 0 0 0 1 0 1 1 0 0 0 0
38H 30H 30H 30H 31H 30H 30H 30H 31H 30H 31H 31H 30H 30H 30H 30H
(80H)

(00H)
Status of
M101
(OFF)
Status of
M100
(ON)

Status of
M103
(OFF)

Status of
M102
(OFF)

Status of
M105
(OFF)

Status of
M104
(ON)

Status of
M107
(ON)

Status of
M106
(ON)

Status of
M109
(OFF)

Status of
M108
(OFF)

Status of
M111
(OFF)

Status of
M110
(OFF)

NOTE
(1)
(2)

9 - 20

Use the designation "00H" when the number of device points is 256 points.
If the number of device points designated is an odd number, one byte of
dummy data (30H) will be added to the response data. For example, if three
points are read, data for four points is returned. The last byte is dummy data.

9 - 20

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MELSEC-F

9.3.3 Batch write in bit units (command: 02)
The examples shown in this section explain the command/response format when
batch writing to the bit device memory.
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Writing the on/off status of M50 to M61 of the PLC on which the Ethernet module is
loaded.

Head device

External device
side
(Example)

L

H

L

-

-

-

-

H

Number of device points

Monitoring
timer

PC No.

(Data name)

Subheader

(1) Communication in binary code
Data for the number
of designed device
points
Characters for the
number of device
points
L

H

L

H

L

H

Subheader

(Data name)
PLC side

Complete code

02H FFH 0AH 00H 32H 00H 00H 00H 20H 4DH 0CH 00H 01H 11 H 01H 00H 00H 01H

(Example)
82H 00H

0 1 1 1 0 1 0 0 0 0 0 1
M51
(ON)
M50
(OFF)

9 - 21

M53
(ON)

M52
(ON)

M55
(ON)

M54
(OFF)

M57
(OFF)

M56
(OFF)

M59
(OFF)

M58
(OFF)

M61
(ON)

M60
(OFF)

9 - 21

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WHEN COMMUNICATING DATA USING THE MC PROTOCOL

MELSEC-F

Head device

External device
side

H L H - - L H - - - - - - - - - - L H L
0 2 F F 0 0 0 A 4 D 2 0 0 0 0 0 0 0 3 2 0 C 0 0 1 1
30H 32H 46H 46H30H 30H 30H 30H 34H 44H 32H 30H 30H 30H 30H 30H 30H 30H 33H 32H30H 43H 30H 30H 31H 31H

-

-

-

-

0 1
30H 31H
Subheader

(Example)

Data for the number
of designed device points
Characters for the
number of device points

(Data name)

PLC side

This designates to turn M50 ON
This designates to turn M51 ON

(Example)
This designates to turn M60 OFF

Complete code

Monitoring
timer

Number of
device points

PC No.

(Data name)

Subheader

(2) Communication in ASCII code

H L
8 2 0 0
38H 32H 30H 30H

This designates to turn M61 ON

NOTE
If the number of device points to be set is an odd number, add one byte of dummy
data (30H) at the end of data written. For example, when writing three points, add the
dummy data (30H) at the end.

9 - 22

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MELSEC-F

9.3.4 Test in bit units (random write) (command: 04)
The examples shown in this section explain the command/response format when
writing data by designating bit device memories arbitrarily.
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Specifying Y45 to ON, M60 to OFF, and S38 to ON at the PLC on which the Ethernet
module is loaded.

H

L

-

-

-

-

H

L

-

-

-

-

H

Designated device

L

-

-

-

-

H

ON/OFF designation

L

Designated device

ON/OFF designation

(Example)

Designated device

ON/OFF designation

External device
side

Number of device points

PC No.

Monitoring
timer

(Data name)

Subheader

(1) Communication in binary code

Y45
(Octadecimal)

PLC side
(Example)

M60

S38

Subheader

(Data name)

Complete code

04H FFH 0AH 00H 03H 00H 25H 00H 00H 00H 20H 59H 01H 3CH 00H 00H 00H 20H 4DH 00H 26H 00H 00H 00H 20H 53H 01H

45 (Octadecimal) = 25 (Hexadecimal)
84H 00H

Designates to turn Y45 ON.
Designates to turn M60 OFF.
Designates to turn S38 ON.

9 - 23

9 - 23

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MELSEC-F

(Example)

Designated device

Designated device

ON/OFF
designation

ON/OFF
designation

Monitoring
timer

Number of
device points

External device
side

PC No.

(Data name)

Subheader

(2) Communication in ASCII code

H L H - - L H L
H - - - - - - - - - - L H L H - - - - - - - - - - L H L
0 4 F F 0 0 0 A 0 3 0 0 5 9 2 0 0 0 0 0 0 0 2 5 0 1 4 D 2 0 0 0 0 0 0 0 3 C 0 0
30H 34H 46H 46H 30H 30H 30H 41H 30H 33H 30H 30H 35H 39H 32H 30H 30H 30H 30H 30H 30H 30H 32H 35H 30H 31H 34H 44H 32H 30H 30H 30H 30H 30H 30H 30H 33H 43H 30H 30H
Y45

M60
OFF M60

ON Y45

Designated device

ON/OFF
designation

45 (Octadecimal) = 25 (Hexadecimal)

S38
ON S38

PLC side

(Example)

9 - 24

Complete code

(Data name)

Subheader

H - - - - - - - - - - L H L
5 3 2 0 0 0 0 0 0 0 2 6 0 1
35H 33H 32H 30H 30H 30H 30H 30H 30H 30H 32H 36H 30H 31H

H L
8 4 0 0
38H 34H 30H 30H

9 - 24

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MELSEC-F

9.3.5 Batch read in word units (command: 01)
The examples shown in this section explain the command/response format when
batch reading the word device memory and the bit device memory (16 point units).
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Reading the on/off status of Y100 to Y137 (32 points) of the PLC on which the
Ethernet module is loaded.

Head device

External device
side
(Example)

L

H

L

-

-

-

-

H

Number of device points

PC No.

Monitoring
timer

(Data name)

Subheader

(1) Communication in binary code

Subheader

(Data name)
Y100 (Octadecimal) = 40 (Hexadecimal)
PLC side

32/16 = 2 points

Complete code

01H FFH 0AH 00H 40H 00H 00H 00H 20H 59H 02H 00H
Data for the
number of designed
device points
Characters for the
number of device
points

(Example)
L

H

L

H

81H 00H 9DH 82H 3EH 55H

1 0 0 1 1 1 0 1 1 0 0 0 0 0 1 0 0 0 1 1 1 1 1 0 0 1 0 1 0 1 0 1
Y107

9 - 25

to

Y100 Y117

to

Y110 Y127

to

Y120 Y137

to

Y130

9 - 25

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MELSEC-F

Number of
device points

Head device

H L H - - L H - - - - - - - - - - L H L
0 1 F F 0 0 0 A 5 9 2 0 0 0 0 0 0 0 4 0 0 2 0 0
30H 31H 46H 46H 30H 30H 30H 41H 35H 39H 32H 30H 30H 30H 30H 30H 30H 30H 34H 30H 30H 32H 30H 30H

PLC side

Subheader

Y100
(Data name)

32/16 = 2 points
Y100 (Octadecimal) = 40 (Hexadecimal)

Data for the number
of designed device
points
Characters for the
number of device
points

H L H - - L H - - L
8 1 0 0 8 2 9 D 5 5 3 E
38H 31H 30H 30H 38H 32H 39H 44H 35H 35H 33H 45H

(Example)

"8"
1

Y117

9 - 26

Complete code

(Example)

Monitoring
timer

External device
side

PC No.

(Data name)

Subheader

(2) Communication in ASCII code

0

"2"
0

0

0

to

0

"9"
1

0

1

0

Y110 Y107

"D"
0

1

1

to

1

"5"

0

1

0

1

Y100 Y137

"5"
0

1

0

to

1

"3"
0

1

0

0

Y130 Y127

"E"
1

1

1

to

1

1

0

Y120

9 - 26

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NOTE
C200 to C255 (Current Values) Batch Read
Since C200 to C255 are 32 bit devices, the device points should be specified as
twice as much as the points actually read.
Also, make sure that the device points are specified by an even number.
If they are specified by an odd number, the batch read cannot be performed. (Error
code 57H will be stored)
Example) When 32 devices are read at one access from C220 to C251 in the PLC
on which the Ethernet module is mounted.

H

L

-

-

-

-

H

Number of
device points

L

Head device

4 bytes x 32=128 bytes

CN220

(Data name)
PLC side
(Example)

32 points x 2 = 64 word

*

Subheader

01H FFH 0AH 00H DCH 00H 00H 00H 4EH 43 H 40 H 00 H

Complete code

(Example)

*

Monitoring
timer

External
device side

PC No.

(Data name)

Subheader

(1) When communicating in binary code

Head data
Low
16bit

High
16bit

L - H

L -H

81 H 00 H 4E H 61 H BCH 00 H

12345678=00BC614EH

9 - 27

Last data
Low
16bit

High
16bit

L - H

L - H

40 H 01 H B9H 02 H

45678912=02B90140H

9 - 27

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MELSEC-F

Monitoring
timer

Head device

H
L
H
L
H - - - - - - - - - - L H L
0
1
F
F
0
0
0
A
4 3 4 E 0 0 0 0 0 0 D C 4 0
0 0
30H 31H 46 H 46 H 30 H 30 H 30 H 41H 34H 33 H 34 H 45 H 30H 30H 30H 30H 30H 30H 44H 43H 34 H 30H 30H 30H

(Data name)
PLC side
(Example)

*

Complete
code

(4 bytes x 2) x 32=256bytes

Subheader

(Example)

*

Number
of device
points

External
device side

PC No.

(Data name)

Subheader

(2) When communicating in ASCII code

Head data
Low 16bit

H 6 1

L
H
8
1
0
0
38 H 31 H 30H 30 H 36 H 31

H

34

Last data

High 16bit

4

L
E
H

45

Low 16bit

H - 0 0 B
H

30

H

30

H

42

L
C
H

12345678=00BC614EH

9 - 28

43

H 0 1
H

4

High 16bit

L
0

H - 0 2 B

30 H 31 H 34 H 30 H 30

H

32 H 42

L
9
H

39 H

45678912=02B90140H

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9.3.6 Batch write in word units (command: 03)
The examples shown in this section explain the command/response format when
batch writing to a word device memory and bit device memory (16 point units).
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Writing data to D100 to D102 of the PLC on which the Ethernet module is loaded.

(Example)

PC No.

L

H

Head device

L

-

-

-

-

H

Number of device points

External device
side

Monitoring
timer

(Data name)

Subheader

(1) Communication in binary code
Data for the number
of designed device
points
Characters for the
number of device
points
L

H

L

H

L

H

D100
Data to be written to D100

PLC side

Data to be written to D101
Data to be written to D102

Subheader

(Data name)

Complete code

03H FFH 0AH 00H 64H 00H 00H 00H 20H 44H 03H 00H 34H 12H 76H 98H 09H 01H

(Example)

83H 00H

9 - 29

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Monitoring
timer

Data for the number of
designed device points
(Characters for the number of device points)

H L H - - L H - - - - - - - - - - L H L
H - - L H - - L H - - L
0 3 F F 0 0 0 A 4 4 2 0 0 0 0 0 0 0 6 4 0 3 0 0 1 2 3 4 9 8 7 6 0 1 0 9
30H 33H 46H 46H 30H 30H 30H 41H 34H 34H 32H 30H 30H 30H 30H 30H 30H 30H 36H 34H 30H 33H 30H 30H 31H 32H 33H 34H 39H 38H 37H 36H 30H 31H 30H 39H
Subheader

D100
(Data name)
PLC side

Complete code

(Example)

Head device

Number of
device points

External device
side

PC No.

(Data name)

Subheader

(2) Communication in ASCII code

H L
8 3 0 0
38H 33H 30H 30H

(Example)

Data to be written to D100
Data to be written to D101
Data to be written to D102

9 - 30

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NOTE
C200 to C255 (Current Values) Batch Write
Since C200 toC255 are 32 bit devices, the device points should be specified twice
as much as the points actually read.
Also, make sure that the device points are specified by even number.
If they are specified by odd number, the batch read cannot be performed. (Error code
57H will be stored)
Example) When 32 points are written at one access from C220 to C251 in the PLC
on which the Ethernet module is mounted.

(1) When communicating in binary code

PLC side
(Example)

9 - 31

L

-

Head device
-

H

03H FFH 0AH 00 H DCH 00H 00H 00H 4EH 43H

Number of
device points

H

High
16bit
L - H

40H 00H 4EH 61H BCH 00H

Last data
Low
16bit
L - H

High
16bit
L - H

40H 01H B9 H 02H

CN220
32 points x 2 = 64word 12345678=00BC614EH 45678912=02B90140H

*

Subheader

(Data name)

L

Head data
Low
16bit
L - H

Complete code

(Example)

Monitoring
timer

External
device side *

PC No.

(Data name)

Subheader

(2 bytes x 2) x 32 = 128 bytes

83H 00H

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(2) When communicating in ASCII code

Head device
- - - 0 0 0 0

H
L
H
L
H - - 0
3
F
F
0
0
0
A
4 3 4 E
30H 33H 46H 46H 30H 30H 30H 41H 34 H 33 H 34 H 45 H 30 H 30

H

30 H 30

0
H

30

0
H

30

D
H

L H L
C 4 0

Head data
Low16bit

0 0

H 6 1

4

44 H 43 H 34 H 30 H 30 H 30 H 36 H 31 H 34

L
E
H

Last data

High16bit

45

Low16bit

H - - L
0 0 B C
H

30 H 30 H 42

H

43

H
0
H

1

4

High16bit

L
0

30 H 31 H 34 H 30

H - 0 2 B
H

30 H 32

H

42

L
9
H

39

H

(Data name)
PLC side
(Example)

9 - 32

32 points x 2 = 64word

12345678=00BC614EH

45678912=02B90140H

*

Complete
code

Monitoring
timer

Subheader

(Example)

*

Number
of device
points

External
device side

PC No.

(Data name)

Subheader

(4 bytes x 2) x 32 = 256 bytes

H
L
0
0
8
3
38 H 33 H 30 H 30 H

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9.3.7 Test in word units (random write) (command: 05)
The examples shown in this section explain the command/response format when
writing data by designating word device memories and bit device memories (16 point
units) arbitrarily. These examples are not applicable for writing the current values of
C200 to C255 (32-bit devices).
For more details on the order and contents of data items of the areas marked by " "
shown in the control procedure diagram, see Subsection 9.1.2.
[Control procedure]
Specifying Y20 to Y37 to on/off, R26 to "1234H," and the current value of C18 to "50H"
at the PLC on which the Ethernet module is loaded.

Designated device

Designated device

Device data

Device data

Device data
(ON/OFF designation)

PC No.

Designated device

Y20

R26

1234H

Current value of CN18

(Data name)

PLC side

50H

Subheader

L H
L - H L H L - H L H L - H L H
05H FFH 0AH 00H 03H 00H 80H 00H 00H 00H 20H 59H 29H 7BH 1AH 00H 00H 00H 20H 52H 34H 12H 12H 00H 00H 00H 4EH 43H 50H 00H
Complete code

(Example)

Number of device points

External device
side

Monitoring
timer

(Data name)

Subheader

(1) Communication in binary code

(Example)
85H 00H

0

Y27

9 - 33

0

1

0

1

to

0

0

1

0

Y20 Y37

1

1

1

1

to

0

1

1

1....ON
0....OFF

Y30

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(Data name)

External device
side

Monitoring
timer

Number of
device points

Subheader

PC No.

(2) Communication in ASCII code
Designated device

Device data
(ON/OFF
designation)

Designated device

Device data

H - - - - - - - - - - L H - - L H - - - - - - - - - - L H - - L
H L H - - L H L
0 5 F F 0 0 0 A 0 3 0 0 5 9 2 0 0 0 0 0 0 0 1 0 7 B 2 9 5 2 2 0 0 0 0 0 0 0 1 A 1 2 3 4
30H 35H 46H 46H 30H 30H 30H 41H 30H 33H 30H 30H 35H 39H 32H 30H 30H 30H 30H 30H 30H 30H 31H 30H 37H 42H 32H 39H 35H 32H 32H 30H 30H 30H 30H 30H 30H 30H 31H 41H 31H 32H 33H 34H

(Example)

Y20

R26

1234H

Y20 (Octadecimal) = 10 (Hexadecimal)

Designated device

Device data

PLC side

(Example)

0

Y37

9 - 34

1

1

1

1

to

0

1

1

0

Y30 Y27

0

1

0

1

to

0

0

Current value of CN18

50H

Complete code

(Data name)

Subheader

H - - - - - - - - - - L H - - L
4 3 4 E 0 0 0 0 0 0 1 2 0 0 5 0
34H 33H 34H 45H 30H 30H 30H 30H 30H 30H 31H 32H 30H 30H 35H 30H

H L
8 5 0 0
38H 35H 30H 30H

1

Y20

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9.4 Remote RUN/STOP, PLC model name code read
This function is used to remotely RUN/STOP a PLC and read the model name of a
PLC from an external device.

9.4.1 Commands and control contents
This section describes the commands and control contents of the control procedure
when controlling the status of the PLC.

(1) Commands
Function

Command / Response type

Remote RUN

13H

Requests remote RUN (execute operation)
Executes a forced RUN regardless of the RUN/STOP switch status of PLC.

Remote STOP

14H

Requests remote STOP (stop operation)
Executes a forced STOP regardless of the RUN/STOP switch status of PLC.

PLC model name read

15H

Request to read the model name of the PLC.

9 - 35

Processing

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9.4.2 Remote RUN (command: 13) / Remote STOP(Command: 14)
The examples shown in this section explain the control procedure of remote RUN.
The order and content of data items of the areas marked by " " shown in the control
procedure diagram differ depending on the module used as well as the frame and
format used for communication.
See the detailed information described in Subsection 9.1.2.
[Control procedure]

(1) Executing remote RUN while communicating in binary code

Monitoring
timer

(Data name)
PLC side

*

Complete code

L
H
13 H
/14 H FFH 0A H 00 H

Subcommand

(Example)

*

PC No.

(Data name)
External device
side

Subcommand

For remote RUN 13H
For remote STOP 14H

(Example)
93 H
/94 H 00 H

For remote RUN 93H
For remote STOP 94H

(2) Executing remote RUN while communicating in ASCII code

PLC side
(Example)

Monitoring
timer

Complete code

(Data name)

H
L
H
L
1
3
F
F
0
0
0
A
31 H 33 H 46 H 46 H 30 H 30 H 30 H 41 H

Subcommand

(Example)

PC No.

(Data name)
External device
side

Subcommand

For remote RUN 3133H (13H)
For remote STOP 3134H (14H)

H
L
9
3
0
0
39 H 33 H 30 H 30H

For remote RUN 3933H (93H)
For remote STOP 3934H (94H)

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POINT
• When executing the remote RUN/STOP using other external devices or
computer link, the remote RUN/STOP is executed in the order of execution.
• When the power of PLC is turned on, then off, and then on again with the
remote RUN/STOP executed, the remote RUN/STOP status is canceled and
the setting of the PLC's RUN/STOP switch becomes valid.

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9.4.3 PLC model name read (command: 15)
The examples shown in this section explains the control procedure for reading the
model name of the PLC.
The order and content of data items of the areas marked by " " shown in the control
procedure diagram differ depending on the module used as well as the frame and
format used for communication.
See the detailed information described in Subsection 9.1.2.
[Control procedure]

Monitoring
timer

(Data name)
External device
side

PC No.

Subcommand

(1) Data communication in binary code

L

(Example)

H

PLC model name

PLC side

Subcommand

(Data name)

Complete code

15 H FFH 0A H 00 H

95 H 00 H

F3 H 00 H

(Example)

Model name of
FX3U/FX3UC

(Example)

1

Monitoring
timer

(Data name)
External device
side

PC No.

Subcommand

(2) Data communication in ASCII code

5

H
F

L
F

H
0

0

0

L
A

PLC side

Complete code

(Data name)

PLC model name

Subcommand

31 H 35 H 46 H 46 H 30 H 30 H 30 H 41 H

H
L
9
5
0
0
F
3
0
0
39 H 35 H 30 H 30 H 46 H 33 H 30 H 30 H

(Example)

Model name of
FX3U/FX3UC

POINT
Distinguish the PLC model name by the model name code.
"F3H", which is the model code of FX3U/FX3UC, is read as the PLC model name.

9 - 38

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9.5 Loopback Test
A loopback test checks whether or not the communication function between an
external device and the Ethernet module operates normally. The examples show the
control procedure using this function.

POINT
(1) A loopback test checks whether or not the connection between the external
device and the Ethernet module is correct and that the data communication
function operates properly when the FX3U-ENET-L is started up or when a
problem occurs.
(2) Use the following data for loopback tests.
Send the head part first.
• When communicating in binary code
Maximum of 254 bytes of numerical values (00 to FFH).
• When communicating in ASCII code
Maximum of 254 single-byte characters ("0" to "9", "A" to "F").

9.5.1 Loopback test (command: 16)
The examples shown in this section explain the control procedure for an external
device performing a loopback test with the Ethernet unit.
The order and content of data items of the areas marked by " " shown in the control
procedure diagram differ depending on the module used as well as the frame and
format used for communication.
See the detailed information described in Subsection 9.1.2.
[Control procedure]

(1) Performing a loopback test while communicating in binary code

(Example)

Last send data

Head send data

Second send data

Monitoring
timer
L

Data length
(1 to 254 bytes)

External device
side

PC No.

(Data name)

Subcommand

Designated byte length+5bytes

H

Last send data

Second send data

Head send data

Complete code

PLC side

Data length
(1 to 254 bytes)

(Data name)

Subcommand

16 H FFH 0A H 00 H

(Example)
96 H 00 H

Designated byte length+3bytes

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(2) Performing a loopback test while communicating in ASCII code

H

F

0

Last send data

Second send data

Head send data

L
0

0

A
H

L

H

L

H

L

H

L

Subcommand

31H 36H 46 H 46 H 30 H 30 H 30 H 41 H

(Data name)
PLC side

(Example)
9

6

H

L

0

0

39 H 36 H 30 H 30 H

H

L

H

L

H

Last send data

L

F

Second send data

H

Head send data

6

Data length
(1 to 254 bytes)

1

Complete code

(Example)

Data length
(1 to 254 bytes)

External device
side

Monitoring
timer

(Data name)

PC No.

Subcommand

(Designated byte length 2)+10bytes

L

H

L

(Designated byte length 2)+6bytes

POINT
The number of the loopback data transmitted by an external device is returned to
the external device it is.
9 - 40

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10 USING THE E-MAIL FUNCTION

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10 USING THE E-MAIL FUNCTION
This chapter explains e-mail functions of the Ethernet module.

10.1 E-mail Function
The e-mail function sends e-mails to PCs or PLCs at a remote location using the
network (via the mail server).
The PLC sends e-mails using sequence programs and buffer memory.

10.1.1E-mail send by the PLC
(1) Sending e-mail by the PLC
When sending an e-mail, the PLC sends the PLC information of a station
connected to an Ethernet module as a file attached to the e-mail or in the text of
the e-mail to an external device such as a PC.
External device
Portable terminal
Sending e-mail by the PLC

PC

(device that

Remark

cannot handle
attached files)

Subject
Attached
file
Main text

—

Binary format
Binary to ASCII conversion

*1

Maximum 2k words

*1

Maximum 256 words.

Binary to CSV conversion
Designating using ASCII data

*1 It is not possible to send an attached file and main text at the same time.

(a) Sending e-mail from the PLC
Data is transmitted via the main text or attached file of an e-mail.
1) For an attached file, device data and other information is sent by
converting into binary/ASCII/CSV data format.
2) For the main text, ASCII code data (character string data) created by a
sequence program is sent.

10

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10 USING THE E-MAIL FUNCTION

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(2) Data conversion method used by the Ethernet module
The following shows the data conversion method used by the Ethernet module.
When sending e-mails

Operation for sending e-mails
(FROM/TO instruction)

PLC

Subject
(ASCII data)

Encode
(Base64/7bit)

Main text
(ASCII data)

Encode
(7bit)

Mail
server

(Binary data)
Attached file
(binary data)

(ASCII data)

Encode
(Base64)

(CSV data)

(3) Flow of the e-mail
The following diagram illustrates the flow of e-mail sent by the PLC to the
external device:
PLC

Ethernet
module

FROM/TO
instruction
(Mail send)

Mail server

1)

Mail server

2)

Mail send

PC
3)

[When sending by the Ethernet module]
1) Send an e-mail to the mail server of the local station's Ethernet module.
2) The mail server of the local station's Ethernet module sends the e-mail to
the receive mail server of the send destination device.
[When receiving by a PC]
3) Mails can be received using applications such as e-mail software.

10

10 - 2

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10 USING THE E-MAIL FUNCTION

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10.2 Configuration and Environment of the Applicable System
This section explains the environment and system configuration for using the e-mail
function from the Ethernet module.
Internet
(Public line)

Internet service provider

Internet service provider
Public line

Router

Proxy server

Access range of Ethernet module
Ethernet

DNS server

Router

TA/modem

SMTP/POP3
(Mail server)

Ethernet

Proxy server

Ethernet

Access range of Ethernet module

DNS server

SMTP/POP3
(Mail server)

Ethernet
Ethernet module

External device

Ethernet module

External device

(1) E-mails can be sent in an environment where the Internet service is available as
shown above. (Ethernet modules do not send e-mails directly via the internet
connection. The mail server sends e-mails.)
(2) Set each Internet mail setting value for the Ethernet module and PC following the
directions from the system administrator.
(3) Each of the Ethernet module parameters for using the e-mail function is set with
FX Configurator-EN-L or a sequence program.

POINT
The module operation is not guaranteed if any of the following connection is
used. Check the module operation on the user side.
• Connections using the Internet (general public line) (Connections using
Internet connection service provided by Internet service providers and
telecommunications carriers)
• Connections using devices in which a firewall is installed
• Connections using broadband routers
• Connections using wireless LAN

10 - 3

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10 USING THE E-MAIL FUNCTION

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10.3 Precautions for Using the E-mail Function
The following explains precautions when using the e-mail function of the Ethernet
module.
(1) Precautions regarding the system
(a) Design the system so that the entire system operates normally at all times
when sending e-mails to/from a running system and controlling the PLC.
(2) Precautions regarding the external device
(a) E-mails can be sent to PLC stations in which Q series Ethernet modules are
installed.
(b) To send files to the Ethernet module as attachments to e-mail, specify the
encoding method (Base 64/7 bits/Quoted Printable) of the attached files.
(3) Common precautions
(a) The maximum sizes of data that can be sent by the Ethernet module are as
follows:
• Data size of attached files: Up to 2048 words
• Data size of main text: Up to 256 words (Sending only)
(b) Mail that is sent do not support encrypted data, compressed data, and data
conversion.
(c) If the external device cannot be found when sending an e-mail from the
Ethernet module, the user can check the error code in the buffer memory.
* If an external device cannot be found when sending e-mail using the
operation of buffer memory, failure of e-mail transmission may not be
recognized, depending on the operation of the mail server. Be sure to
verify the receiver's e-mail address in advance.
* Error codes are stored within BFM#10335. (For details on error codes,
refer to section 11.4.)
(d) The e-mail function is supported for SMTP.
(e) When e-mail communication errors occur, check the error codes stored in
the mail send error log area of the buffer memory.
(f)

When the receive data of an e-mail sent is abnormal (garbled characters,
etc.), review the transmission data format (binary/ASCII/CSV) designated
with BFM#10338.
* The Subject should be in ASCII code data format. (It is not converted to
ASCII format.)

(g) Confirm with a system administrator regarding the minimum time intervals
for accessing the mail server when sending e-mail, reading received e-mail,
and inquiring whether or not there is any received e-mail.
Depending on the mail server's security setting, frequent access may be
prohibited.

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10 USING THE E-MAIL FUNCTION

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10.4 E-mail Specifications
The following table lists the specifications of the e-mail function.
Item
Data size

Specification
Attached file

2048 words

1

256 words

1

Main text

When sending: Sends either a file as attachment or main text (select one).

Data transfer method
Subject

US-ASCII format or ISO-2022-JP (Base 64)

Attached file format

MIME format

MIME

Version 1.0
Binary/ASCII/CSV can be selected.

Data of attached file format

File name: XXXX.bin (binary), XXXX.asc (ASCII), XXXX.csv (CSV)
(CSV: Comma Separated Value)

Transmission

Division of attached file

Cannot be divided (only one file can be sent)
Subject: Base 64/7 bits

specifications
Transmission

When sending (encode)

Main text: 7 bits
Attached file: Base 64

data
Encryption

No

Compression

No
Port number

Communication with mail
server

SMTP

POP
Operation check mailer

Authentication
method
Port number

1 to 65535 No authentication, POP before SMTP: 25 (initial)
SMTP-AUTH: 587
• No authentication
• SMTP-AUTH (PLAIN, LOGIN, CRAM-MD5)
• POP before SMTP
1 to 65535

Microsoft

POP3: 110 (initial)

Corporation Outlook

Express 6

NOTE
Mail terminology list:
DNS server: Server that manages networks
SMTP server: Server that delivers (transfers) e-mail between mail servers
POP3 server: Server that transfers received e-mail addressed to subscribers to
the corresponding subscribers

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10 USING THE E-MAIL FUNCTION

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10.5 Processing Procedure of the E-mail Function
The following flowchart illustrates the procedure that is required before sending
e-mails:

Start
When DNS is not used
When DNS is used

Register the DNS server
See Section 10.6 (1)

Register the mail address of the local station's Ethernet module

Register the mail address of
the external device
See Section 10.6 (3)

Setting the email parameters using FX Configurator-EN-L or the
ladder and re-initialize the Ethernet module.

1
Send data as
an attached file
of an e-mail

See Section 10.7

1

Send data as
main text of e-mail
See Section 10.8

1 The open and close processing of
the communication line for
sending e-mails is automatically
executed by the Ethernet module.

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10.6 E-mail Settings
This section explains the settings required to send e-mails.
(1) DNS settings
Specify the IP address of the DNS server when setting the mail server name
using the domain name from the e-mail settings (see (2)).

BFM number

Setting name

DNS setting

[Decimal]

Description of setting

Setting range/options

IP address of DNS server 1 20505 to 20506 Set IP address of DNS server 1.

—

IP address of DNS server 2 20507 to 20508 Set IP address of DNS server 2.

—

IP address of DNS server 3 20509 to 20510 Set IP address of DNS server 3.

—

IP address of DNS server 4 20511 to 20512

—

Set IP address of DNS server 4.

(a) DNS settings
Set the IP addresses of the domain name system (DNS) servers designated
by a system administrator.
1) Designate the IP addresses of the DNS servers 1 to 4.

POINT
(1) The DNS servers manage networks.
DNS settings are required to allow search for the SMTP server or POP3
server from a domain name.
(2) Adjust the DNS settings when the mail server name shown in item (2) is
specified with a domain name.
Setting is not required when it is specified with an IP address.
(3) When obtaining the IP addresses from a domain name, the DNS servers are
searched sequentially starting from the first DNS server.

NOTE
To adjust settings using FX Configurator-EN-L, select [Initial Settings] from the initial
screen and adjust the settings at the initial settings screen.

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10 USING THE E-MAIL FUNCTION

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(2) E-mail settings
Set in order to use the e-mail function.
[Setting item]
BFM number

Setting item

General setting

Password

9913 to 9920

Mail address

9856 to 9887

Specification

9921

method
SMTP
setting

STMP server
name / IP address

number

name

*1

Specification

setting*1

24320

POP server name
/ IP address

number*1
SMTP authentication method

24388

24321

SMTP
setting

SMTP login ID

24324 to 24355

SMTP password

24356 to 24387

—

module (64 characters or fewer)
Select send mail server specification
method

name (64 characters or less) or IP
Set port numbers of the outgoing mail
server. (initial: 25)
Select receive mail server specificastion method

server domain name (64 characters or
less)

POP3 server port

authentication

Set the mail address for the Ethernet

Set the IP address or receiving mail
9955 to 9986

—

(16 characters or fewer)

address

9954

method
POP

9922 to 9953

Setting range/option

Set the password to the POP3 server

Set the sending mail server domain

SMTP server port
Mail server

Description of setting item

[Decimal]

Set port numbers of the incoming mail
server. (initial: 110)
Set the authentication method for the
outgoing mail server.

0: Domain name specification
1: Decimal
2: Hexadecimal
IP address setting :
00000001 to FFFFFFFEH
1 to 65535
0: Domain name specification
1: Decimal
2: Hexadecimal
IP address setting :
00000001 to FFFFFFFEH
1 to 65535
0: No authentication
1: SMTP-AUTH
2: POP before SMTP

Set the login ID of the outgoing mail
server (64 characters or fewer)
Set the password of the outgoing mail
server (64 characters or fewer)

—
—

*1 The setting is required only when "POP before SMTP" is selected in the SMTP authentication method.

(a) General settings
Designate the mail setting values that have been registered with the mail
registration information designated by the system administrator.
1) Password:
Designate the mail password of the local station's Ethernet module.*1
2) Mail address:
Designate the mail address of the local station's Ethernet module.
(b) Mail server name
Set the IP addresses or domain name of the mail servers designated by the
system administrator.
1) Select the input format (decimal/hexadecimal) of the IP addresses.
2) Set the IP address or sending mail server (SMTP) domain name.
3) Set the IP address or receiving mail server (POP3) domain name.*1
4) Set port numbers of the outgoing mail server (SMTP).
5) Set port numbers of the incoming mail server (POP3).*1
*1 The setting is required only when "POP before SMTP" is selected in the
SMTP authentication methed.
10 - 8

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10 USING THE E-MAIL FUNCTION

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POINT
• The mail server must be designated in order to use the e-mail function. (See
POINT of (1).)
(c) SMTP authentication setting
1) Set the authentication method for the outgoing mail server (SMTP).
The steps 2) and 3) below are required when "SMTP-AUTH" is selected in
the SMTP authentication method.
2) Set the login ID of the outgoing mail server (SMTP).
3) Set the password of the outgoing mail server (SMTP).

NOTE
To adjust the settings in FX Configurator-EN-L, select [Email Settings] from the initial
screen and adjust the settings from the email settings screen.

(3) Send mail address setting
Register the e-mail address of the external devices where e-mail is to be sent.
[Setting item]
BFM number

Setting Item name

[Decimal]

Send mail address 1

9987

to

to

Send mail address 10

10306

Description of setting
Set the mail address of the transmission
destination (1 to 10)

Setting
range/Selections
—

(a) Send mail address
1) Designate the mail addresses of a maximum of 10 external devices to
which mail is being sent from the local station's Ethernet module. (Only
one e-mail address can be specified for each area.)
2) When sending e-mail by the Ethernet module, specify the send e-mail
address by the bit 0 to 9 of BFM#10337.

NOTE
To adjust the settings in FX Configurator-EN-L, select [Email Settings] from the initial
screen and adjust the settings from the email settings screen.

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10 USING THE E-MAIL FUNCTION

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10.7 Sending E-mail (Attached Files) by the PLC
This section explains how to send attached files when sending e-mails.

10.7.1When sending data as an attached file
The following explains the buffer memory addresses and program for sending e-mail.
The following instruction shows how to store data in an attached file and send it to an
external device.
1) Check whether mail can be sent or not.
(BFM#10334 b15: OFF)
2) Designate the destination of the mail.
Turn the bit corresponding to the e-mail destination address to ON in BFM#10337.
To send to all of the mail addresses registered, write to "3FFH".
3) Write the mail data to the following buffer memory addresses.
(Subject:
BFM#10339 to 10402)
(Attached file format:
BFM#10338)
(Word count of attached file:
BFM#10403)
(Contents of main text or attached file: BFM#10404 to 12451)
4) Write "0001H" in BFM#10333 to send the mail.
5) Read BFM#10334 to check if mail was correctly sent.

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10 USING THE E-MAIL FUNCTION

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The table below shows the buffer memory to be used for sending mail.
BFM number
Items

Decimal

Contents

(Hexadecimal)
10333
(285DH)
10334
(285EH)

10335
(285FH)

10336
(2860H)

Mail sending command

Mail sending status

Error codes when sending
e-mail

Start mail sending (0001H)
Ignore (0000H)
Initial status (0000H)
Mail sending normally completed (0001H)
Mail sending abnormally completed (0002H)
Mail being sent (8000H)
When sending mail, the error code is cleared by the mail sending command (BFM
#10333: 0001H), and error code is stored if an error occurs.
When sending mail to multiple addresses, the first error code found is stored, even
after other errors.
The second error and later errors are not stored.
Sending destination address 1

Result of sending e-mail

Success (b0: ON) / Failure (b0: OFF)
to

Sending destination address 10

10337

Designation Address

(2861H)

of e-mail

Success (b9: ON) / Failure (b9: OFF)

Turns the bit of the e-mail destination address to ON.
Sending destination address 1
Enable (b0: ON) / Disable (b0: OFF)
to
Sending destination address 10
Enable (b9: ON) / Disable (b9: OFF)
Sends the attached file in binary format (0000H)

10338
(2862H)

Attached file format

Sends the attached file in ASCII format (0001H)
Sends the attached file in CSV format (0002H)
Sends the attached file as a text mail (0004H)
Stores a subject (maximum 128 characters)
Subject consists of the send destination number and the character data designated by

10339 to 10402
(2863 to 28A2H)

the sequence program.
Subject

(It is not converted to ASCII format.)
* The Subject should be designated in ASCII characters in the sequence program.
* When the subject consists of less than 128 characters, write "\0" at the end of the
subject

10403
(28A3H)
10404 to 12451
(28A4 to 30A3H)

Word count of attached file

Designates the word count of attached file (0 to 2048)

Main text or attached file

Stores a main text or an attached file

(1) Send using the sequence program
The following explains how an e-mail is sent by the sequence program.
See (3) sending data for detail.

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10 USING THE E-MAIL FUNCTION

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• Program example for the unit No. 1
X000

Mail
sending
instruction

M102

Mail abnormally

M103 completed

(M100

)

Mail sending
request
(Self-holding)

Mail
normally
completed

M100
[MOV

Mail sending
request
(Self-holding)
M101
[MOV

Mail
sending
(Selfholding)

U1\
G10334

D100

Mail
sending
status

Mail
sending
status

U1\
G10336

D101

]

]

Individual Individual
success
success
and failure and failure
D100.0
[PLS

Mail
sending
status

M102

]

Mail
normally
completed
K1000
(C0

)

Success
count
D100.1
[PLS

Mail
sending
status

M103

]

Mail
abnormally
completed
K1000
(C1

)

Failure
count
D100.F
[MOVP

H3

U1\
G10337

]

Setting
of send
destination
bit

Mail
sending
status

[$MOVP "testmail msend"

U1\
G10339

]

Subject

[MOVP

H1

U1\
G10338

]

Mail
sending
format
[CALLP

P0

]

Creates
text data

[MOVP

K3

U1\
G10403

]

Attachment
size
[WBFM

K1

K10404

R1000

K2048

K32

]

H1

U1\
G10333

]

Head of
attached
data
M8029
[MOVP

Write of
attached
data
completed

Mail
sending
instruction

M101
(M101

Mail
sending
(Self-holding)

10 - 12

)

Mail
sending
(Selfholding)

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[FEND

]

P0

M8000
[ZRST

Creates
text data

R1000

R1002

]

R1000

]

Head of
attached
data

M8000
[MOV

R1234

Head of
attached
data

10 - 13

[MOV

H5678

R1001

]

[MOV

R9ABC

R1002

]

[SRET

]

[END

]

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10 USING THE E-MAIL FUNCTION

MELSEC-F

(2) Execution timing of the instruction
Initial
processing
Initial processing
normal completion

Mail sending
completed

Mail
sending start

1)
2)

Writing the necessary data
for sending a mail to BFM
Mail sending request
BFM#10333

Writing the mail
data to BFM
3)
0000H

0000H

0001H

4)
Mail sending status
BFM#10334

8000H

0001H (Normally completed)
0002H (Abnormally completed)

Communication
with a SMTP
server

0000H

1)
2)

3)
4)

Check whether the initial processing has been completed normally.
Write mail data to the buffer memory.
(Mail sending destination: BFM#10337 b0 to b9)
(Subject: BFM#10339 to 10402)
(Attached file format: BFM#10338)
(Word count of attached file: BFM#10403)
(Contents of main texts or attached files: BFM#10404 to 12451)
Write "0001H" in BFM#10333.*1
The e-mail is sent to the mail server.
When sending to the mail server is complete, the result is stored in
BFM#10334.*2
*1 Specify the attached file format by writing a parameter in BFM#10338
before sending e-mail.
0000H: Sends the attached file in binary format
0001H: Sends the attached file in ASCII format
0002H: Sends the attached file in CSV format
0004H: Sends the attached file as a text mail
*2 For details on causes of errors, see "Troubleshooting" in Chapter 11.

(a) Designate binary format when communicating between Ethernet modules.
The name of the attached file is mmddhhss.bin (system date.bin).
mm: Month dd: Date hh: Hour ss: minute
(b) Designate either binary format, ASCII format or CSV format when a PC/UNIX
receives e-mail sent from an Ethernet module.
1) When binary format is designated
The name of the attached file is mmddhhss.bin (system date.bin).
mm: month dd: day hh: hour ss: minute
2) When ASCII format is designated
The name of the attached file is mmddhhss.asc (system date.asc).
mm: month dd: day hh: hour ss: minute
3) When CSV format is designated
The name of the attached file is mmddhhss.csv (system date.csv).
mm: month dd: day hh: hour ss: minute
* For details on how to receive e-mails, see (3).
* The system date for the file name is the data managed by the PLC in
which the Ethernet module is installed.

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10 USING THE E-MAIL FUNCTION

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(3) Receiving with a personal computer
The following explains how a PC/UNIX receives e-mails sent from the Ethernet
module.
After setting an environment with application software that processes e-mails,
e-mails can be received on a receive message screen as shown below.
(Example) The following shows an example of the received e-mail.
(The screen display shows Microsoft Corporation's Outlook
Express 6.)

Mail address of Ethernet module

(a)

Mail address of external device
"No.00001 testmail msend"

(b)
(c)


123456789abc

(a) From
Displays the mail address of the Ethernet module.

NOTE
By entering the mail addresses of the send destination devices in the address book,
the registered names (display names) can be displayed and makes management
easier.
(b) Subject
This indicates the transmission destination No. (*1) and the Subject
written by a sequence program.
*1 The Ethernet module automatically adds this number, sequentially
starting from 00001.
(After the maximum number (99999) is reached, the number starts from
00000.)
(c) Attached file
This indicates the name of the attached file sent by the Ethernet module.

POINT
Data in the attached file in CSV format can be read in cell units in Excel, etc., for
each word of data.
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10 USING THE E-MAIL FUNCTION

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10.7.2Contents of the attached files
The following explains the contents of the attached file data.
The data format of the attached file is ASCII code (ASCII format, CSV format) or
binary code (binary format).
The following example shows the transmission contents for each data format (binary/
ASCII/CSV) when the Ethernet module sends the data register value as an attached
file.
(1) When sending from the Ethernet module
Ethernet module
In case of binary

BFM#
10404

1234H

10405

5678H

BFM#
10413
9AH BCH

BFM#
BFM#
10405
10404
56H 78H 12H 34H

External device

In case of ASCII
BFM#
10413
BIN ASCII
conversion

"C"

BFM#
10405

"B" "A" "9"

"8"

"7"

"6"

"5"

BFM#
10404
"4"

"3"

"2"

"1"

In case of CSV
BFM#
10413
10413

9ABCH

BIN CSV
conversion

"C"

BFM#
10405
, "8"

"B" "A" "9" ,

"7"

"6"

"5"

,

"4"

"3"

BFM#
10404
"2" "1"

(2) Data configuration in CSV format
Data in CSV format can be used as control data for the cell units in Excel, etc.
Data in CSV format handled by the Ethernet module is the data expressed as
follows.
• 1 word (16 bits) binary data is converted to four digit ASCII code when
expressed as a hexadecimal. (4 bytes of ASCII code)
• When handling multiple word data, insert comma data between each word
(4 bytes of ASCII code).
Data is sent in the following arrangement.
Arrangement of data
1) In addition to the data conversion and insertion described above, CR
(code: 0DH) and LF (code: 0AH) are inserted for each 8 words of data.
2) The arrangement of data sent in CSV format is shown below.
D0
D8
D16
D24

,
,
,
,

D1
D9
D17
D25

,
,
,
,

D2
D10
D18
D26

,
,
,

D7

[CR + LF]

D15

[CR + LF]

D23

[CR + LF]

[CR + LF]

8 device
(8-word unit)

10 - 16

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10 USING THE E-MAIL FUNCTION

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10.8 Sending E-mail (Main Text) by the PLC
This section explains how to send the main text of e-mail.

10.8.1When sending data as main text of e-mail
The following explains the buffer memory address and sequence program for sending
e-mail.
This section explains how to store the data in main text and send it to the external
device.
1) Check whether mail can be sent or not.
(BFM#10334 b15: OFF)
2) Destination of the mail.
Turn the bit corresponding to the e-mail destination address to ON in
BFM#10337.
To send to all of the mail addresses registered (maximum 10 addresses),
write 3FFH.
3) Write the mail data to the following buffer memory addresses.
(Subject: BFM#10339 to 10403)
(Attached file format: Set "0004H" : BFM#10338)
(Mail text/word count of attached file : BFM#10403)
(Contents of main text: BFM#10404 to BFM#12451)
4) Write "0001H" to BFM#10333 to send the mail.
5) Read the value in BFM#10334 to check if mail was correctly sent.

10 - 17

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10 USING THE E-MAIL FUNCTION

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The table below shows the buffer memory to be used for sending mail.
BFM number
Item

Decimal

Description

(Hexadecimal)
10333
(285DH)

Mail sending command

Start mail sending (0001H)
Ignored (0000H)
Initial status (0000H)

10334
(285EH)

Mail sending status

Mail sending normal completed (0001H)
Mail sending abnormal completed (0002H)
Mail being sent (8000H)
When sending mail, the error code is cleared by the mail sending command (BFM

10335
(285FH)

Error codes when sending
e-mail

#10333: 0001H), and error code is stored if an error occurs.
When sending mail to multiple addresses, the first error code found is stored, even
after other errors.
The second error and later errors are not stored.

10336
(2860H)

Sending destination address 1
Sending result of e-mail

Success (b0: ON) / Failure (b0: OFF)
to

Sending destination address 10

Success (b9: ON) / Failure (b9: OFF)

Turns the bit of mail destination address to ON.
10337
(2861H)

Destination Address of e-mail

Sending destination address 1

Enable (b0: ON) / Disable (b0: OFF)
to

Sending destination address 10
10338
(2862H)

Attached file format

Enable (b9: ON) / Disable (b9: OFF)

Write 0004H for sending the attached file as main text.
Stores a subject (maximum 128 characters)
Subject consists of the send destination number and the character data designated

10339 to 10402
(2863 to 28A2H)

by the sequence program.
Subject

(It is not converted to ASCII format.)
*The Subject should be designated in ASCII characters in the sequence program.
*When the subject consists of less than 128 characters, write "\0" at the end of the
subject.

10403
(28A3H)

Word count of attached file

Designates the word count of main text (0 to 256)
Stores a main text or an attached data
Main texts are not converted to ASCII format by the Ethernet module.
*It should be designated in ASCII characters in the sequence program.

10404 to 12451
(28A4 to 30A3H)

Main text data

*The following binary code data is processed as control codes:
0D0AH: Line feed code CR + LF
00H: End of main text
*It is recommended to use 78 characters or less in a single line of main text.
(Be sure to add a line feed code CR + LF (0D0AH) at the end of the main text lines.)

10 - 18

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10 USING THE E-MAIL FUNCTION

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(1) Send using the sequence program
Method for sending e-mails by the sequence program is similar to the one by an
attached file.
See Subsection 10.7.1 for sample programs for sending e-mail from PLC.
(2) Receiving by a personal computer
The following explains how a PC/UNIX/portable terminal receives e-mail sent
from the Ethernet module.
After setting an environment for using the Internet with application software that
processes e-mails, e-mails can be received on a receive message screen as
shown below.
(Example) The following shows an example of a received e-mail.
(The screen display shows Microsoft Corporation's Outlook
Express 6.)

Mail address of Ethernet module

(a)

Mail address of external device
"No.00001 testmail msend"

(b)
(c)

(a) From
Displays the e-mail address of the Ethernet module.

NOTE
By entering the mail addresses of the send destination devices in the address book,
the registered names (display names) can be displayed and makes management
easier.
(b) Subject
This indicates the transmission destination No. (*1) and the Subject written
by a sequence program.
*1 The Ethernet module automatically adds this number, sequentially,
starting from 00001.
(After the maximum number (99999) is reached, the number starts again
from 00000.)
(c) Main text of e-mail
This indicates the main text of the e-mail sent by the Ethernet module.

10 - 19

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11 TROUBLESHOOTING

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11 TROUBLESHOOTING
This section explains the contents of the errors that may occur during communication
between the Ethernet module and an external device as well as the troubleshooting
procedures.
The following are methods for checking if there is an error on the Ethernet module
side and the contents of the error.
Use one of the following methods to check if there is an error and its content, then
take corrective actions.

(1) Check using the display LED on the front of the Ethernet module
(See Section 11.1.)
The display LED on/off status can be used to check if an error is occurring in the
Ethernet module.

(2) Check through FX Configurator-EN-L
FX Configurator-EN-L can be used to check various conditions of the Ethernet
module as well as the error code corresponding to the contents of the error
occurring and to perform tests.
(a) Ethernet diagnostics (See Subsection 11.2.2.)
1) PING test (See Subsection 5.4.1.)
2) COM. ERR off (See Subsections 11.1.2 and 11.2.1.)

(3) Check through GX Developer
(a) Buffer memory batch monitor
The error code can be checked by monitoring the buffer memory of the
Ethernet module.

(4) Check the contents of the error using the error code (See Section
11.4.)
The contents of the error can be checked using the error code confirmed on the
dedicated screen above or by monitoring the buffer memory by referring to
Section 11.4.

NOTE
If line errors and other errors occur when connecting devices of multiple
manufacturers, the users needs to isolate the malfunctioning parts using line
analyzers, etc.

11 - 1

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11 TROUBLESHOOTING

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11.1 How to Check Errors Using LED Displays

11

This section describes the errors that can be checked with the LED displays on the
front of the Ethernet module.

11.1.1 Checking error display
The following can be checked with the LED displays on the front of the Ethernet
module.


LED name

Status to check

Cause/corrective action

1

RUN

Turns off after powering on
the Ethernet module.

1) Watchdog timer error
• A watchdog timer (approximately 600 ms) error is detected by the self diagnosis
function of the Ethernet module.
2) Base module power is OFF, or the extension cable is not connected.

2

INIT.

Off

1) Failed to re-initialization due to a parameter error
• Check/correct the parameter setting values for the Ethernet modules using a sequence
program or the FX Configurator-EN-L and re-download.
2) Base module power is OFF, or the extension cable is not connected.

Does not turn on

1) Using 10Mbps HUB
• Initial processing.
• Replace with 100Mbps HUB.
2) Does not turn on using 100Mbps HUB
• Check the connection of the connectors on the Ethernet side and the HUB side.
• Replace the cable.

Turns on after powering on
the Ethernet module.

1) Module parameter setting error
• Check/correct the parameter setting values for the Ethernet modules using the
sequence program or the FX Configurator-EN-L and re-download.
2) PLC error
• When the PLC [RUN] LED is off/flashing, or the [ERR.] LED is on, check the content of
the error occurring in the PLC and correct the problem.
3) Ethernet module error (H/W error)
4) Base module power is OFF, or the extension cable is not connected.

Turns on after powering on
the Ethernet module.
Or turns on temporarily

1) Check the contents of the error using the error codes stored by the error detection of the
following processing and remove the causes.
• Initial processing
• Fixed buffer send processing
• E-mail send processing
• Open processing
• MC protocol communication processing
• Other processing (processing for which error codes are stored in the error log area)
2) For a list of error codes, see Section 11.4.

3

4

5

100M

ERR.

COM.ERR.

(Continues on the following page)

11 - 2

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11 TROUBLESHOOTING

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(Continued from the previous page)

LED name

6

SD

Status to check
The [SD] LED does not flash
at data sending.

Cause/corrective action
1) [ERR.] or [COM.ERR] LED turns on.
Remove the factors that turn on the [ERR.] or [COM.ERR] LED.
2) Program reviewing is required
Review the sequence program for sending.
1) [ERR.] or [COM.ERR] LED turns on.
Remove the factors that turn on the [ERR.] or [COM.ERR] LED.
2) Poor cable connection

7

8

RD

C1 to C4

[RD] LED stays off and data
cannot be received.

Check the connection of the cable. (*1)
3) Local station IP address setting error
If the cable connection is all right, review each setting value of the local station IP
address, router setting, and sub-net mask settings using FX Configurator-EN-L.
4) Program reviewing is required
Review the sequence program for sending.
1) Poor cable connection
Check the connection of the cable.
2) Program or parameter reviewing is required
• Check the program or parameter.
• Check error contents with the diagnosis function of FX Configurator-EN-L.

Does not turn on

*1 Confirm the completion for the initial processing and check whether or not there is any problem in the cable
connection and the Ethernet lines.
See Section 5.4, "Confirming the completion of the Initial Processing" for details on confirming the
completion for the initial processing. (Perform either one of the "Confirming the completion of the initial
processing completion" actions described in Section 5.4.)

POINT
The on/off status of the [INIT], [OPEN], [ERR.] and [COM.ERR] LEDs is stored in
the module status area (BFM#28) of the buffer memory.
For more details, see Section 3.6, "List of Applications and Assignments of the
Buffer Memory".

11 - 3

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11 TROUBLESHOOTING

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11.1.2 How to turn off COM.ERR LED and to read/clear error information
This section explains how to turn off [COM.ERR] LED and to read/clear error
information using a sequence program.

(1) How to turn off [COM.ERR] LED using buffer memory
The [COM.ERR] LED on the front of the Ethernet module is turned on when a
communication error occurs in an external device. (BFM#28...b4: ON)
(a) The [COM.ERR] LED is turned off by writing "0001H" to the off request signal
(BFM#1601).
[COM.ERR] LED off request signal
BFM#1601=0001H

W
0001H

R
0000H

(LED on)

R
0002H

W
0001H

(LED off)

(LED off)

R
0002H

(LED on)

(LED on)

[COM.ERR] LED on
BFM#28, b4

Error occurrence

Error
occurrence

Error
occurrence

Error
occurrence

(b) The off processing is performed by writing "0001H" to BFM#1601.
(c) The error information in the error log area of the buffer memory is not cleared
(deleted) even if "0001H" is written to BFM#1601.

(2) How to turn off [COM.ERR] LED on the "Ethernet diagnostics"
screen of FX Configurator-EN-L (See Subsection 11.2.2.)
(a) Clicking on the COM.ERR off button turns the [COM.ERR] LED off.
(b) The error information in the error log area of the buffer memory is not cleared
(deleted).

(3) Reading buffer memory to read error information
Read the error information stored in the buffer memory of Ethernet module.
The "Initial alarm code" and each connection's "Open alarm code" are stored in the
following buffer memory.

11 - 4

Initial error code

BFM#105

Error code for connection 1

BFM#124

Error code for connection 2

BFM#134

Error code for connection 3

BFM#144

Error code for connection 4

BFM#154

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(4) How to clear error information by writing to buffer memory
Writing to BFM#31800 to 31802 allows clearing the error information and turning
off COM.ERR.

MOV

HFFFF

U \
G31800

Set error information to clear

MOV

H0000

U \
G31801

Error log and LED off instruction

MOV

H0001

U \
G31802

Error clear execution processing

SET

M100

Set a flag that indicates that the
error is being cleared

RST

M100

Reset a flag that indicates that the
error is being cleared after the error
has been cleared.

M100
=

U \
H0002
G31802

corresponds to the module number.

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11.2 How to Check an Error Through FX Configurator-EN-L
The status of the various settings for the Ethernet module can be checked using the
FX Configurator-EN-L functions.

(1) Ethernet diagnostics (See Section 11.2.2.)
The block status of an Ethernet module, parameter settings, communication
status, error log and others can be checked using the diagnostic function.
The following are the functions of the diagnostics.
Diagnostics

Parameter status
Checks the stored parameters after the
initial processing for the Ethernet module.
(See Section 5.2.)
Error log
Checks the error stored in the error log area.
(See Section 11.4.)
Status of each connection
Checks the status of each connection after the
connection to the external device is established
with the open processing. (See Section 5.6.)
Status of each protocol

Send e-mail information
Checks the information for sent e-mail.
(See Section 11.4.)
PING test

See Section 5.4

Checks the completion of the initial processing
with the issuance of the PING command.

COM.ERR. off

See Subsection 11.1.2

Turns off the [COM.ERR.] LED on the front
of the Ethernet module.

Checks the communication status of each
protocol supported by the Ethernet module.
LED status
Checks the on/off status of the LED on the
front of the Ethernet module. (See Section 11.1.)

(2) Buffer memory batch monitor (See Section 11.3.)
The buffer memory of an Ethernet module is monitored.

POINT
See Subsection 11.2.1 for the buffer memory that can be checked on the
"Ethernet diagnostics" screen.

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11.2.1 Buffer memory that can be monitored with the FX Configurator-EN-L diagnostic
function
The following is a list of the buffer memory addresses that can be displayed on the
"Ethernet diagnostics" screen of FX Configurator-EN-L.
BFM address
Decimal
(hexadecimal)

32 (20H)

33 (21H)

D Destination existence
confirmation (b1)
Pairing open (b7)
Connection No.1
Communication system (protocol)
(b8)
Open system (b15, b14)
Connection No.2 (same as connection No.1)
Connection No.3

Protocol

Open system
Unpassive

34 (22H)

TCP
Fullpassive
UDP

35 (23H)
105 (69H)
106 to 107
(6A to 6B H)
108 to 110
(6C to 6E H)
120 (78 H)
121 to 122
(79 to 7A H)
123 (7B H)
124 (7C H)

200 (C8 H)
227 (E3 H)
229 (E5 H)
230 (E6 H)
231 (E7 H)
232 (E8 H)
233 (E9 H)
234 to 235
(EA to EB H)
236 (EC H)
238 to 372
(EE to 174 H)
376 to 377
(178 to 179 H)
378 to 379
(17A to 17B H)
380 to 381
(17C to 17D H)

—

Existence
confirmation

Setting value

Performed

8403H

Not performed

8401H

Performed

C403H

Not performed

C401H

Performed

0503H

Not performed

0501H

Local station IP address

Display contents
Existence confirmation
Connection No.1

Open system
Connection No.2 (same as connection No.1)

Status of each
connection
Connection No.3 (same as connection No.1)

Connection No.4 (same as connection No.1)
Initial error code
Parameter status

Module information

Local station Ethernet address

Connection No.1

IP address
Ethernet address

Local station Port No. (Decimal)

Local station Port No.

Destination IP address

Destination IP address

Destination Port No.
Open error code
Fixed buffer sending error code*1
Connection end code

Status of each
connection

Connection No.2 to 4 (same as connection No.1)
[INIT.]LED (b0)
[C1] to [C4] LED (b8 to b11)
LED on/off status
[ERR.]LED (b3)
[COM.ERR.] LED (b4)
Number of error occurrence
Error code/End code
Subheader
Command code
Connection No.
Error log block 1
Local station Port No. (Decimal)

Connection No.1

Connection No.2 to 4 (same as connection No.1)

LED status

LED display status

Latest
Error log

Destination Port No.
No.2 to 16 (same as the latest error log block)
Total number of echo reply sends

Received IP packet count
Status of each
Received IP packet count
discarded due to sum check error protocol

INIT.
C1 toC4
ERR.
COM.ERR.
Number of error occurrences
Error code/End code
Subheader
Command code
Connection No.
Local station Port No.
Destination IP address

Destination Port No.
Error log block 2 to 16 (same as error log block 1)

Sent IP packet total count

Destination Port No.
Open error code
Fixed buffer transfer error code*1
Connection end code

Destination IP address

IP

Paring open
Protocol

Connection No.4 (same as connection No.3)
Initial error code

125 (7D H)
126 (7E H)
130 to 159
(82 to 9F H)

Ethernet diagnostics
display screen

Applicable buffer memory

IP packet

Total number echo request sends
Total number echo reply receives

*1 Supported in the connections No. 1 and 2 only.

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11 TROUBLESHOOTING

BFM address
Decimal
(hexadecimal)
408 to 409
(198 to 199 H)
410 to 411
(19A to 19B H)
412 to 413
(19C to 19D H)
414 to 415
(19E to 19F H)
416 to 417
(1A0 to 1A1 H)
418 to 419
(1A2 to 1A3 H)
420 to 421
(1A4 to 1A5 H)
440 to 441
(1B8 to 1B9 H)
442 to 443
(1BA to 1BB H)
444 to 445
(1BC to 1BD H)
472 to 473
(1D8 to 1D9 H)
474 to 475
(1DA to 1DB H)

Applicable buffer memory

ICMP

Ethernet diagnostics
display screen

Display contents

Received ICMP packet count

Total number of receives

Received ICMP packet count
discarded due to Sum check error

Total number of Sum check error
annulments

Sent ICMP packet total count

Total number of sends

Echo request total count of received
ICMP packets
Echo reply total count of sent ICMP
packets
Echo request total count of sent
ICMP packets
Echo reply total count of received
ICMP packets

ICMP packet

TCP

UDP

23358 (5B3E H)
23359 (5B3F H)
23361 (5B41 H)
23362 (5B42 H) Send
23363 to 23370
(5B43 to 5B4A H)
23371 to 23374
(5B4B to 5B4E H)
23375 to 23404
(5B4F to 5B6C H)
23405 to 23712
(5B6D to 5CA0 H)

Total number echo request
receives
Total number of echo reply sends
Total number of echo request
sends
Total number of echo reply
receives

Status of each
protocol

Received TCP packet count

476 to 477
(1DC to 1DD H)
23355 (5B3B H)
23356 (5B3C H)
23357 (5B3D H)

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MELSEC-F

Received TCP packet count
discarded due to Sum check error

Total number of receives
TCP packet

Total number of Sum check error
annulments

Sent TCP packet total count

Total number of sends

Received UDP packet total count

Total number of receives

Received UDP packet count
discarded due to Sum check error

UDP packet

Sent UDP packet total count
Number of mails normally completed
Number of attached file sends
Number of sends to the server
Number of mails abnormally
completed
Number of error log writes
Error code
Send e-mail
Command code
information
To
Error log block 1
Send date
Subject
Error log block 2 to 8
(same as error log block 2 to 16)

Total number of Sum check error
annulments
Total number of sends

Number of mails normally completed
Number of attached file sends
Number of sends to the server
Number of mails abnormally completed
Number of error log writes
Error code
Command code
To
Latest error log
Send date
Subject
Error log block 2 to 8
(same as error log block 1)

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11.2.2 Ethernet diagnostics
[Purpose]
The block status of an Ethernet module, parameter settings, communication status,
error log and others can be checked using the Ethernet diagnostic function of
FX Configurator-EN-L.
[Operating procedure]
FX Configurator-EN-L

Diagnostics

Diagnostics

[Ethernet diagnostics screen]

1)
2)

7)
3)
4)
5)
6)

[Explanation of items]
No.

Item

Description

1

Change IP address display

Switches the IP address display between decimal and hexadecimal.

2

Selection from the various
information monitors

Various types of information for the Ethernet module can be monitored.
(See Subsection 11.2.1 for the buffer memory corresponding to the display contents.)

3

PING test

Performs the PING test on the external device. (See Subsection 5.4.1, Subsection
5.4.2.)

4

COM. ERR off

Clicking this button turns the [COM.ERR.] LED off. (See Subsection 11.1.2.)

5

Start monitor

Clicking this button executes the Ethernet diagnostics.
The display is updated during monitoring.

6

Stop monitor

Clicking this button stops the Ethernet diagnostics.
The display is retained while monitoring is stopped.

7

Clear history

Clicking this button executes the clears the log.

11 - 9

Setting range
Decimal/hexadecimal

—

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11.3 Checking the error information by the buffer memory batch monitoring function
It is explained here how the Ethernet module errors can be checked from GX
Developer.
Error codes stored in the buffer memory of the Ethernet module can be monitored
using the "Buffer memory batch monitoring" function of GX Developer.
[Operating procedure]
(Step 1) Select [Online] - [Monitor] - [Buffer memory batch] from the GX Developer
menu bar, and start the "Buffer memory batch monitoring" screen.
(Step 2) Enter [Module start address:].
Assign a special module number to each base module following the order
that 0 is assigned to the rightmost module, 1 to the second rightmost module,
and goes same up to 7.
However, for FX3UC-32MT-LT(-2) which incorporates the CC-Link/LT
function, the first special module will be assigned with No.1.
(Step 3) Enter [Buffer memory start address:].
Enter the buffer memory address to be monitored, using the selected input
format (decimal/hexadecimal).
For a list of the buffer memory addresses where error codes are stored, see
Section 11.4, "Error Code List".
(Example)
When monitoring the initial abnormal code (BFM #105):
Enter "105" + "decimal"
(Step 4) Click the Start Monitor button.
The contents of the buffer memory after the specified address are displayed.
(In case of the above example, the contents of 105H and succeeding
addresses are displayed.)

POINT
To see if the PLC base module recognizes the FX3U-ENET-L or not, monitor BFM
#30.
If BFM #30's value is K7132, the FX3U-ENET-L is being recognized.

NOTE
The display format can by modified as follows:
Monitor format

: Bits & words/ Multiple bit points/ Multiple word points

Display

: 16-bit integer/32-bit integer/real number/ASCII character

Numerical value

: Decimal/hexadecimal

For details, refer to the "Operating Manual" for GX Developer.

11 - 10

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11.4 Error Code List
This section explains the error codes (abnormal codes) for the errors that may occur
in each processing when communicating data between the Ethernet module and an
external device as well as those generated by processing requests from the local
station's FX series PLC.

11.4.1 Type of error incident
The details of errors and error handling procedures are described.
Type of error

Description

Error code storage buffer memory
BFM#105............. Initial error code
(Communication status storage area)

1

Errors occurring in initial processing

• Setting value error
• Initial processing error

2

Errors occurring in open processing

• Setting value error
• Open processing error

BFM#124............. Open error code
(Communication status storage area)

3

Errors occurring in fixed buffer
sending to an external device

• Designated data error
• Sending error

BFM#125..............Fixed buffer sending error code
BFM#126..............Connection end code
(Communication status storage area)

4

Errors occurring in fixed buffer
communication with an external
device

• Designated data error
• Communication error
(exclude 3 above)

BFM#126...............Connection end code
(Communication status storage area)

• Errors returned in fixed buffer communication (end code)
5

Errors returned to an external device
when communicating with the
external device

• Error returned in communication
using MC protocol

Explanation

Subsection
11.4.4

Subsection
11.4.2

End codes when A compatible 1E frame commands
are used

Subsection
11.4.2

Error codes when A compatible 1E frame commands
are used

Subsection
11.4.3

6

Errors occurring while
communicating with an external
device (including the causes shown
in the description column), and
whose error codes are stored in the
error log area.

• Designated data errors
• Errors whose source cannot be
confirmed
• Errors that occurred while
communicating using MC protocol

BFM#229
(Error log area)

Subsection
11.4.4

7

Errors occurring when sending e-mail

• Setting data error
• Sending error

BFM#23355 Send
(E-mail status storage area)

Subsection
11.4.4

* For error codes sent back by data communication using MX Component, refer to the MX Component Programming Manual.

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(1) Initial error code (BFM#105)
(a) This address stores the error codes generated when the initial processing is
executed.
(b) Error codes are stored as binary values when the initial abnormal completion
signal (BFM#28...b5) is on.
(c) An error code is cleared when the initial normal completion signal
(BFM#27"0001H", BFM#28...b0: ON) is turns on, but can also be cleared by
the following operations.
1) Writing the value in BFM#1600 to perform re-initialization or turning off
the PLC and Ethernet module
2) Re-downloading the parameter with FX Configurator-EN-L or sequence
pragram

(2) Open error code
(connection numbers: 1 to 4; BFM#124 to 154)
(a) These addresses store the result of the open processing for the applicable
connections.
(b) The results of the open processing are stored in binary values.
0
: Normal completion
Other than 0 : Abnormal completion (BFM#28 b6: ON)
(c) An error code is cleared by the following operations.
1) Reopening the connection that caused an open error
2) Performing the re-initial processing by writing the value to BFM#1600

(3) Fixed buffer sending error code
(connection numbers: 1 to 2; BFM#125 to 135)
(a) These addresses store error codes generated when an error in data sending
to an external device occurs during fixed buffer communication using the
applicable connection.
(b) A sending error code is cleared when the next data sending is normally
completed.

(4) Connection end code
(connection numbers: 1 to 2; BFM#126 to 136)
(a) These addresses store end codes returned from an external device as a
response during the fixed buffer communication using the applicable
connection.
(b) Determine how to handle the end codes in the responses by arranging with
the particular external device.

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(5) Error log area (BFM#227 to 372)
This area stores the following errors.
• Errors whose source cannot be confirmed
• Errors that occurred during communications using the random access buffer
• Errors that occurred during communications using MC protocol
(a) Number of error occurrences (BFM#227)
1) This address stores the number of errors registered in the error log block
area.
2) When errors occur more than 65536 times, the count is stopped at
FFFFH (65535).
(b) Error log write pointer (BFM#228)
1) This address stores the error log block number where the latest error
logging is registered.
0
: No error. (No registration of error log)
1 or more : Error log block number where the latest error logging is
registered
* If the pointer value is "16", it means that the latest error logging is
registered in the error log block 16 area.
2) When 17 or more errors occur, the registration of error logging starts from
error log block 1 area again.

POINT
(1) An error log block area consists of sixteen error log blocks that have the same
data order.
(2) The error information continues to be stored into the following areas even if
the count of the error occurrences is stopped and no longer stored:
• Error log write pointer storage area
• Error log block
(c) Error log block - Error code/end code (starting from BFM#229)
1) In the error code/end code area, error codes are stored that indicate error
content. (See Section 11.3.)
(d) Error block - Subheader (starting from BFM#230)
1) The subheader code of a faulty message is stored in bits 0 to 7 of the
corresponding area. ("0" is stored in bits 8 to 15).
2) For errors below the TCP and UDP levels, "0" is stored.
(e) Error log block - Command code (starting from BFM#231)
1) This block stores the command code of a errors message.
b15

to

b0

Command code

2) "0" is stored in the following case.
• For messages not containing a command code
• For errors below the TCP and UDP levels (because their commands
are unknown)

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11 TROUBLESHOOTING

(f)

MELSEC-F
Error log block - Connection No. (starting from BFM#232)
1) The faulty connection No. is stored in bits 0 to 3 of the corresponding
area. ("0" is stored in bits 4 to 15).
2) For errors below the TCP and UDP levels, "0" is stored.

(g) Error log block - Local station Port No. (starting from BFM#233)
1) This block stores the local station's port No. when an error occurred.
2) "0" is stored for errors below the TCP and UDP levels.
(h) Error log block - Destination IP address (starting from BFM#234)
1) This block stores the IP address of an external device when an error
occurred.
2) "0" is stored in the following cases.
• For errors below the IP level
• When an error response was relayed through the PLC.
(i)

Error log block - Destination Port No. (starting from BFM#236)
1) This block stores the external device's port No. when an error occurred.
2) "0" is stored for errors below the TCP and UDP levels.

(j)

Status for each protocol (BFM#376 to 511)
1) This address stores the count of the occurrence for the applicable
contents of each protocol's condition.
(The value counted by the Ethernet module.)
2) When the count value exceeds two words, the count stops at
FFFFFFFFH (4294967295).

POINT
Values stored in the buffer memory are cleared when the Ethernet module's local
station is powered on. (They are not cleared during the initial processing.)
Normally, it is not necessary to read this area; so, read it as needed during
maintenance.

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(6) E-mail status storage area (BFM#22640 to 24575)
* When the storage count exceeds FFFFH times, the count starts from 0H again.
(a) E-mail status storage area for sending (BFM#23355 to 23712)
1) Number of mails normally completed (BFM#23355)
• This address stores a cumulative count of how many times the
Ethernet module transferred send mails to the Send mail server.
0

: No mail was sent.

1 or more : The number of normal completions of mail sending
2) Attached file sending count (BFM#23356)
• This address stores a cumulative count of how many times the
Ethernet module sent mails with files attached.
0

: No mail with files attached has been sent.

1 or more : The number of normal completions of mail sending with
files attached
3) Sending to the server count (BFM#23357)
• This address stores a cumulative count of sending to the send mail
server.
0

: No mail was sent to the server.

1 or more : Cumulative count of sending to the server
4) Number of mails abnormally completed (BFM#23358)
• This address stores a cumulative count of communication error
occurrences that are returned when requesting sending to the
transmitting mail server.
0

: No communication error between servers, or no
transmission has been made

1 or more : Cumulative count of communication error occurrences
5) Error log write count (BFM#23359)
• This address stores a cumulative count of registrations made to the
sending error log block area.
0

: No error, or no inquiry has been made to the server.

1 or more : Cumulative count of registrations made to the error log
block area

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6) Sending error log write pointer (BFM#23360)
• This address stores the error log block area number where the latest
sending error logging is registered.
0

: No error. (No registration of sending error log)

1 or more : Error log block number where the latest sending error
logging is registered
* If the pointer value is "8", it means that the latest error logging is
registered in the sending error log block 8 area.
• When 9 or more sending errors occur, the registration of sending error
logging starts from sending error log block 1 area again.

POINT
The sending error log block area consists of eight error log blocks that have the
same order of data items.

7) Error log block - Error code (BFM#23361 onwards)
• This block stores the error codes that indicate the contents of errors.
(See Section 11.4.)
8) Error log block - Command code (BFM#23362 onwards)
• This block stores the system command codes for the error causing
messages.
9) Error log block - To (BFM#23363 onwards)
• This block stores eight words from the beginning of the sending source
mail address of an error causing e-mail during communication with the
mail server, in ASCII code characters.
(Example)
If the sending source mail address was
"use@from.add.sample.co.jp",
"use@from.add.sam" is stored as ASCII code characters.
10)Error log block - Date (BFM#23371 onwards)
• This block stores the time and date on which the e-mail is sent in BCD
code.
• The order of date and time to be stored is the same as for the date and
time of e-mail reception shown in (a) 11).
11) Error log block - Subject (BFM#23375 onwards)
• This block stores 30 words from the beginning of the Subject of the
e-mail.
• A Subject is not stored successfully if it contains characters other than
alphanumeric and ASCII code.

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11.4.2 End codes (Complete codes) returned to an external device during data
communication
This section explains the end codes (complete codes) that are added to responses
when communicating using the fixed buffer or the MC protocol.
For more details on the error codes that are added to responses during
communication using A compatible 1E frames through the MC protocol, see
Subsection 11.4.3.
For more details on the end codes (error codes) that are stored in the buffer memory
of the Ethernet module, see Subsection 11.4.4.

End code
00H

Description
• Normal completion

Processing

Communication function
Fixed

MC

-

• Codes for command/response type of subheader are not within the
specifications.

50H

• Check and correct command/
response type set by an
external device.
Command/
Communication processing
(The Ethernet module
response type
automatically adds command/
Communication using fixed buffer
60H
response type; the user does
00 to 05 H
not need to set these.)
Communication using MC protocol
13 to 16 H
See NOTE in Subsection
11.4.4.
• In communication using the fixed buffer, if the data length setting is less than the
• Check and correct the data
actual data count, the remaining data is determined as the second data and
length.
processed. In this case, a subheader undefined command type error may occur.

54H

• When "ASCII code communication" is selected (BFM #24b1: ON) in the
[Communication data code settings] of operational settings parameters of
• Check and correct the send
FX Configurator-EN-L, ASCII code data that cannot be converted to binary code
data of the external device.
was received from an external device.

56H

• Device designation from an external side is incorrect.

57H

• Correct the device designated.

• The number of points for a command designated by an external device exceeds
the maximum number of processing points for each processing (number of
processes that can be executed per communication).
• Head device number to the designated points exceeds the maximum addresses • Correct the designated points
(device number).
or device number.
• When performing batch read/write operations on C200 to C255, the address
(device numbers), which was designated with the odd number of points, is
exceeded.
• Byte length of a command does not conform to the specifications.
• When writing data, the set number of data points written is different from the
value of the designated number.

• Check the data length of the
command and redo the data
setting.

• Head device number of a command designated by an external device is set
outside the range that can be designated.

• Designate the appropriate
values within the range that
are allowed for each
processing.

58H

• A word device is designated in a command for bit devices.
• Correct the command or the
• The head number of bit devices is designated by a value other than a multiple of
designated device.
16 in a command for word devices.
• Fix the faulty parts by referring
to the abnormal codes
appended to the end codes
(see Subsection 11.4.3).

5BH

• The PLC and the Ethernet module cannot communicate.
• The PLC cannot process requests from an external device.

60H

• Communication time between the Ethernet module and the PLC exceeded PLC • Increase the monitoring timer
monitoring timer value.
value.

Fixed

11 - 17

: Fixed buffer communication

MC

: Communication using MC protocol

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11.4.3 Abnormal codes returned during communication using MC protocol
This section explains the abnormal codes (error codes) that are added to responses
when communicating using MC protocol (An abnormal code is added only when an
end code is "5B".)
For more details on the end codes (error codes) that are added to responses, see
Subsection 11.4.2.
For more details on the end codes (error codes) that are stored in the buffer memory
of the Ethernet module, see Subsection 11.4.4.
Response format

Subheader

End code

Abnormal code

00H

When an abnormal code is stored, the end code is "5BH."
Error code
(hexadecimal)

Error

Description of error

Corrective action

PC number error

The PC number designated was not "FF".

11H

Mode error

Poor communication between the Ethernet module and the PLC
(1)Communicate again. If an error occurs again,
(1)After the Ethernet module receives a request successfully from an
check noise, etc. and replace the Ethernet
external device, the Ethernet module and the PLC could not
module, then communicate again.
communicate for some reason (noise, etc.).

18H

Remote error

Remote RUN/STOP not accessible.
The PLC base module status is CPU ERR or PROG ERR.

10H

11 - 18

(1)Set the PC number to "FF"..

(1)Check whether or not the base module has a
CPU ERR (light on) or PROG ERR (flashing
light).

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11.4.4 Error codes stored in the buffer memory
When an error occurs at each data communication processing between the Ethernet
module and an external device, the error code (abnormal code) is stored in the buffer
memory of the Ethernet module. This section explains the contents of this type of
errors and error handling procedures.
The "Storage destination" column in the error code list indicates the buffer memory
where the applicable error code is stored.
The names used for the explanation indicated in the "Storage destination" column
corresponding to the buffer memory error code storage areas shown in the table
below. (Error codes whose storage destination is not written are returned to the
external device.)
Note that the buffer memory may store error codes of the messages returned from the
external device. For error codes not shown in this manual, refer to the manual of the
external device and check the returned messages.
Name used for explanation

Buffer memory

Buffer memory address

Initial

Initial abnormal code area

BFM#105

Open

Open abnormal code area

BFM#124...

Fixed sending

Fixed buffer sending abnormal code area

BFM#125...

Connection

Connection end code/error log area

BFM#126...

Error code

Error code/end code area

E-mail log

E-mail error log area

BFM#229...
BFM#23361...

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
0050H
0051H
0052H
0054H
0055H

The content of these errors and the error handling for each error code is the same as the end
codes (0050 to 0060H) returned to the external device.
Check the explanation of the applicable code shown in Subsection 11.4.1, and take actions
accordingly.

0056H
0057H
0058H
0059H
005BH

Read and handle the error code and end code
area.

0060H

11 - 19

11 - 19

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361

C001H

• At initial processing, the IP address setting
value of the Ethernet module is incorrect.
• When using the router relay function, the
setting value of the sub-net mask field is
incorrect.

• Correct the IP address.
Set the class to A/B/C.
• Correct the sub-net mask.

C002H

At initial setting, some of the various timer
setting values are outside the allowable range.

• Review and correct the necessary timer
values at initial processing.

C004H

The setting value of the sub-net mask field is
incorrect.

• Correct the sub-net mask and execute the
initial processing again.

C005H

• The setting value of the default router IP
address for the router relay function is
• Correct the default router IP address and
incorrect.
execute the initial processing again.
• Network address (network address after sub- • Set the network address to the same network
net mask) of the default router IP address is
address as the local station's Ethernet
different from the network address of the local
module IP address.
station's Ethernet module IP address.

C006H

The setting value of the sub-net address for the • Correct the sub-net address and execute the
initial processing again.
router relay function is incorrect.

C007H

• The setting value of the router IP address for
• Correct the router IP address and execute
the router relay function is incorrect.
the initial processing again.
• Network address (network address after sub• Set the network address to the same network
net mask) of router IP address is different
address as the local station's Ethernet
from the network address of the local station's
module IP address.
Ethernet module IP address.

C010H

At open processing, the setting value of the
Ethernet module port number is incorrect.

• Correct the port number.

C011H

At open processing, the setting value of an
external device's port number is incorrect.

• Correct the port number.

C012H

The port number set is used in a connection
already opened by TCP/IP.

• Review and correct the port numbers of the
Ethernet module and external device.

C013H

The port number used in a connection already
opened is set in UDP/IP open processing.

• Review and correct the port number of the
Ethernet module.

C014H

Initial processing and open processing of the
Ethernet module is not completed.

• Execute the initial processing and open
processing.

C015H

At open processing, the setting value of an
external device's IP address is incorrect.

• Correct the IP address.
Set the class to A/B/C.

C016H

The pairing open processing of the connection
(or the next connection) designated for pairing
open has already been completed.

• Check that the open processing of both of
the target connections for pairing open is not
executed.
• Review the combination for pairing open.

C017H

A connection could not be established during
the open processing of a TCP connection.

• Check the operation of the external device.
• Check the open processing of the external
device.
• Correct the open settings of the
communication parameters.
• Review the Ethernet module's port number
and the IP address/port number and open
system of the external device.
• Check that the connection cable is not
dislocated.

C018H

The setting value of an external device's IP
address is incorrect.
* When TCP is used, FFFFFFFFH
cannot be set as an IP address.

• Correct the IP address.

11 - 20

11 - 20

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C020H

Data length exceeds the allowable range.

• Correct the data length.
• If the data transmitted is larger than the
allowable size, divide and then send it.

C021H

An abnormal end response was received after a
transmission using fixed buffers.

• Read the end code of the response from the
connection end code/error log area, and
handle as needed.

C022H

• A response could not be received within the
response monitoring timer value.
• The applicable connection was closed while
waiting for a response.

• Check the operation of the external device.
• Review and correct the response monitoring
timer value.
• Check the open status of the applicable
connection.

C023H

• The open processing for the applicable
connection is not completed.
• The applicable connection is closed.

• Execute the open processing of the
applicable connection.

A sending error occurred.

• Check the operation of the external device.
• Send after an arbitrarily selected time has
elapsed because packets may be congested
on the line.
• Check that the connection cable is not
dislocated.

C032H

A TCP ULP timeout error occurred in the TCP/
IP communication.
(An external device does not return ACK.)

• Check the operation of the external device.
• Correct the TCP ULP timeout value and
execute the initial processing again.
• Send after an arbitrarily selected time has
elapsed because packets may be congested
on the line.
• Check that the connection cable is not
dislocated.

C033H

• Review and correct the external device's IP
address and the Ethernet address.
• If the external device has the ARP function,
set the initial value. If not, set the Ethernet
address of the external device.
• Check the operation of the external device.
• Send after an arbitrarily selected time has
An external device side with the set IP address
elapsed because packets may be congested
does not exist.
on the line.
• Check that the connection cable is not
dislocated.
• Just after powering ON, there are cases
when the connected hub is not booted, so
send will occur after an arbitrary time period
has elapsed.

C035H

The existence of an external device could not
be confirmed within the response monitoring
timer value.

C040H

• Not all the data could be received within the • Review and correct the data length of the
response monitoring timer value.
communication data.
• Sufficient data for the data length could not
• Review and correct each setting value at the
be received.
initial processing because the packets may
• The remaining part of a message divided at
be congested on the line.
the TCP/IP level could not be received within • Send the same data from the external device
the response monitoring timer value.
again.

C030H

11 - 21

• Check the operation of the external device.
• Review and correct each setting value for the
existence confirmation.
• Check that the connection cable is not
dislocated.

11 - 21

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C041H
C042H
C043H
C044H
to
C048H

When TCP is used, the checksum of the receive
• Review the checksum on the external device
data is incorrect.
side and send the correct value.
When UDP is used, the checksum of the
• Investigate the conditions of the line (noise,
receive data is incorrect.
distance between the line and power line,
The checksum in header of IP packet received
contact of each device, etc.)
is incorrect.
An error packet of ICMP was received.

C049H

An error packet of ICMP was received.

C04AH

An error packet of ICMP was received.
(An IP assembly timeout error occurred in an
external device.)

• Check the operation of the external device.
• Check that the connection cable is not
dislocated.
• Check the operation of the external device.
• Send after an arbitrarily selected time has
elapsed because packets may be congested
on the line.
• Check that the connection cable is not
dislocated.
• Correct the IP assembly timer value of the
external device existence timer timeout.

• Check the operation of the external device.
• Send after an arbitrarily selected time has
elapsed because packets may be congested
An IP assembly timeout error occurred.
on the line.
*1 (The remaining part of divided data could not be
C04BH
• Check that the connection cable is not
received and a timeout occurred.)
dislocated.
• Correct the IP assembly timer value and
execute the initial processing again.
C04CH

Cannot send because there is no space in the
internal buffer, e.g. the IP header buffer.

C050H

• Select binary code communication in the
ASCII code data that cannot be converted to
operational settings, and restart the Ethernet
binary code is received when ASCII code
module.
communication is set in the operational settings
• Correct the data sent from the external side
of the Ethernet module.
and send again.

C051H
to
C054H

The number of read/write points is outside the
allowable range.

• Correct the number of read/write points and
send to the Ethernet module again.

C056H

• Read/write request exceeds the maximum
address.
• Address is 0.

• Correct the head address or the number of
read/write points and send to the Ethernet
module again.
(The maximum address must not be
exceeded.)

C059H

Incorrect designation of command and
subcommand.

• Review the content of the request.

The Ethernet module cannot read from/write to
the designated device.

• Examine the device to be read/written.

C05CH

The content of a request is incorrect.
(Requesting read/write in bit units to word
devices.)

• Correct the content of the request and send
to the Ethernet module again.
(Correction of subcommand, etc.)

C05EH

Communication time between the Ethernet
module and PLC exceeded the monitoring
timer.

• Increase the monitoring timer value.
• Check whether or not the PLC operates
normally.

C05AH
C05BH

*1

• Send the same data again and check that the
response is received.

When this error occurs, the COM.ERR light turns on, but turns off again about one second later.

11 - 22

11 - 22

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C05FH

The request could not be executed on the target • Correct the network number and PC number.
• Correct the content of the read/write request.
PLC.

C060H

The content of a request is incorrect.
(Incorrect data was designated for bit devices,
etc.)

• Correct the content of the request and send
to the Ethernet module again.
(Correction of data, etc.)

C072H

The content of a request is incorrect.
(Requested read/write in bit units to word
devices.)

• Check whether the content can be requested
to the target PLC.
• Correct the content of the request and send it
to the Ethernet module again.

C073H

Request was not supported by the Ethernet
module of the target PLC.

• Review the content of the request.

C086H

A message exceeding the receive message
size was received.

• Correct the send message size from the
requesting source.

C091H

System Error
(Flash ROM write error)

(*1)

C093H

System Error
(The parameters written to flash ROM are
abnormal.)

(*1)

C0B5H

Data that could not be processed by the PLC/
Ethernet module was designated.

• Review the content of the request.
• Cancel the current request.

C0B9H

The open processing of the applicable
connection is has not been completed.

• Execute the open processing.
• Check the operation of the external device.

C0BAH

Cannot acknowledge sending request since the
• Execute the open processing and make a
close processing is being executed via the
sending request.
CLOSE instruction.

C0BBH

System error
• The OS detected any error.

C0BCH

Designated communication line is closed.

• Open the communication line.
• Review the target connection number.

C0BDH

Cannot send by acknowledging continuous
requests.

• Check whether or not requests are made
continuously without waiting for responses.

C0BEH
C0BFH

System error
• The OS detected any error.

(*1)

(*1)

C0C0H

The receiving completion confirmation signal
was turned on when the receiving completion
signal was not on.

• Review and correct the program.

C0C1H

The transmission interval of UDP is too short.

• Check whether or not sending requests are
repeated.
• Make the sending interval longer.

C0C2H
to
C0C3H

Systevm error
• The OS detected any error.

C0C4 H

Re-initialization was started during
communication

• Execute re-initialization after closing all
connections.

C0C5 H

• A sending request was made to an external
device whose class/network address are
different from those of the local station when
the router relay function is not used.
• The setting of the router relay parameter is
incorrect.

• Execute the initial processing by setting that
the router relay function should be used.
• Set the correct data for the router relay
parameter.
• Correct the IP address of the external device
and execute the open processing.
• Check that the network address is correct.
When it is changed, execute the initial
processing again.

C0C6H

System error
• The OS detected any error.

11 - 23

(*1)

(*1)

11 - 23

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C0C7H

An Ethernet module system error occurred.

C0C8H
to
C0CAH

System error
• The OS detected any error.

C0CBH

Another sending request was made when the
sending processing has not been completed.

C0CCH

• Execute the initial processing again.
• Execute the processing by referring Section
11.5 POINT (3).
(*1)
• Make the next sending request after the
previous sending is completed.

C0CFH

System error
• The OS detected any error.

C0D9H

Incorrect subcommand value was designated.

• Correct the designated value for the
subcommand.

C0DAH

A response to the PING test could not be
received within the time of the communication
time check.

• Review the IP address/host name of the
Ethernet module for the PING test.
• Change the status of the Ethernet module for
the PING to allow communication (to the
status after the initial processing is
completed).

C0DBH

There is an error in the IP address/host name of • Review the IP address/host name of the
Ethernet module for the PING test.
the Ethernet module for the PING test.

C0DCH
to
C0DDH

System error
• The OS detected any error.

(*1)

(*1)

C0DFH

C0E0H
to
C0EFH

An error was detected in the PLC.

• Check the connection cables between the
PLC, extended I/Os or special module.
• Check that no error has occurred in the PLC.
If an error is found, take corrective actions
according to error description of the PLC.
• Replace the PLC and/or special function
block.

C0F0H

An Ethernet module RAM abnormality was
detected in the hardware test.

• Conduct a hardware test again. If an
abnormality is detected again, the Ethernet
module hardware may be faulty.
Consult your nearest branch office or dealer
with the details of the errors.

C0F1H

An Ethernet module ROM abnormality was
detected in the hardware test.

• Conduct a hardware test again. If an
abnormality is detected again, the Ethernet
module hardware may be faulty.
Consult your nearest branch office or dealer
with the details of the errors.

C0F4H
to
C0F6H

System error
• The OS detected any error.

C0F8 H

• Check the sequence program again.
• Check whether or not there is a contact
failure on the extension connector.
• Check whether or not there are any factors
Attempted to access to a buffer memory No. for
possibly causing noise.
which no base module of the PLC exists.
• The Ethernet module hardware may be
faulty.
Consult your nearest branch office or dealer
with the details of the errors.

11 - 24

(*1)

11 - 24

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361

Handshake error on TO instruction with a base
module

• Check whether or not there is a contact
failure on the extension connector.
• Check whether or not there are any factors
possibly causing noise.
• The Ethernet module hardware may be
faulty.
Consult your nearest branch office or dealer
with the details of the errors.

Base module 5V error
• There is no power to the base module
• The extension connector is not connected
• The Ethernet module was turned on before
the base module.

• Check that power to the base module is ON.
• Check that there are no connection errors on
the extension connector.
• Turn on the base module and Ethernet
module at the same time.
• There may be a hardware problem with the
Ethernet module or the base module.
Consult your nearest branch office or dealer
with the details of the errors.

C0FBH

Error detected at base module
• An error is occurring at the base module
• The extension connector is not connected

• Review the sequence program.
• Check that there are no connection errors
with the extension connector.
• There may be a hardware problem with the
Ethernet module or the base module.
Consult your nearest branch office or dealer
with the details of the errors.

C100H

System error
• The OS detected any error.

C101H

• Check the address of the DNS server.
• Check whether or not it is possible to
communicate with the DNS server using the
A response could not be received from the DNS
Ping command.
• Check that the IP addresses of the local
client.
station and DNS server are in the same
class. (If the class is different, check the
router setting.)

C102H

A response from the SMTP layer could not be
received.

• Check that the SMTP server name is
registered in DNS.
• Delete the SMTP server name, change to the
IP address setting, and check the operation.
• Check whether or not it is possible to
communicate with the SMTP server using
the Ping command.

C103H

DNS settings incorrect.

• Check the DNS mail address.
• Check the content of the DNS setting.

C104H
to
C106H

System error
• The OS detected any error.

C0F9 H

C0FAH

(*1)

(*1)

C110H

C111H

• Check cable, hub, etc.
A response could not be received from the DNS • Check whether or not it is possible to
communicate with the DNS server using the
client.
Ping command.

C112H

• Check that the POP3 server name is
registered in DNS.
• Delete the POP3 server name, change to the
IP address setting, and check the operation.
• Check whether or not it is possible to
communicate with the POP3 server using the
Ping command.

11 - 25

A response from the POP3 layer could not be
received.

11 - 25

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C115H
to
C118H

System error
• The OS detected any error.

(*1)

C11CH

Mail address not found.

• Check whether the mail setting of the
parameter setting is correct or not.
• When the mail server and Ethernet module
are connected via the router, check whether
the router setting is correct or not.
• Test-send a mail to the address where it will
be received without fail. When the test is
normally completed, recheck whether the
domain name after "@" is correct or not.

C11DH

The size of the attached file exceeded the
allowable size.

• Check that the attached file is less than
2 k word.
• Check that the sending side did not divide
the file.

C120H

Could not open the SMTP server.

• Check the port number of the SMTP server
setting.
• Check whether or not it is possible to
communicate with the SMTP server using
the Ping command.

C121H

Cannot communicate with the SMTP server.
(Error response)

• Check the port number of the SMTP server
setting.
• Check if the SMTP server is busy.

C122H

Cannot communicate with the SMTP server.
(Abort)

• Check if the SMTP server is busy.

C123H

Cannot communicate with the SMTP server.
(Reset response)

• Check if the SMTP server is busy.

C124H

A response from the SMTP server timed out.

• Check whether or not the SMTP server is
faulty.
• Check whether or not there is too much load
on the network.

C125H

Forcefully disconnected from the SMTP server.

• Check whether or not the SMTP server is
faulty.

C126H

Could not close the SMTP server.

• Check whether or not the SMTP server is
faulty.
• Check whether or not there is too much load
on the network.

C127H

Closing the SMTP server gave an error
response.

• Check whether or not the SMTP server is
faulty.

C130H

Communication channel is closed because the
service is not available.

• Check the status of the SMTP server.

C131H

The SMTP server was performing processing
and an error response was received.

• Check if a user name not registered in the
server was designated.
• Send again after arbitrary set time has
passed.

C132H

The SMTP server was performing processing
and an error response was received.
(Local error)

• Check the status of the SMTP server.

C133H

The SMTP server was performing processing
and an error response was received.
(Insufficient memory area)

• Check the status of the SMTP server.

C134H
to
C137H

System error
• The OS detected any error.

C138H

The SMTP server was performing processing
and an error response was received.
(Mailbox not found)

11 - 26

(*1)

• Check that the Ethernet module's mail
address is set correctly.

11 - 26

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C139H

System error
• The OS detected any error.

C13AH

The SMTP server was performing processing
and an error response was received.
(Exceeded the allocation of memory area)

• Check the status of the SMTP server.

C13BH

The SMTP server was performing processing
and an error response was received.
(Illegal mail box name)

• Check that the Ethernet module's mail
address is set correctly.

C13CH

System error
• The OS detected any error.

C13DH

SMTP server authentication error.

• Check whether the SMTP login ID and SMTP
password are correct.
• Check the SMTP server status.

SMTP server authentication nonsupport error

• Check whether the SMTP server supports
authentication.
• Set [SMTP authentication method] to [No
authentication] or [POP before SMTP].

C140H

Could not open the POP3 server.

• Check the port number of the POP3 server
setting.
• Check whether or not it is possible to
communicate with the POP3 server using the
Ping command.

C141H

Cannot communicate with the POP3 server.
(Error response)

• Check the port number of the POP3 server
setting.
• Check if the POP3 server is busy.

C142H

Cannot communicate with the POP3 server.
(Abort)

• Check if the POP3 server is busy.

C143H

Cannot communicate with the POP3 server.
(Reset response)

• Check if the POP3 server is busy.

C144H

Could not receive a response from the POP3
server.

• Check whether or not the POP3 server is
faulty.
• Check whether or not there is too much load
on the network.
• Check that the correct password is being
sent to the POP3 server.

C145H

Forcibly disconnected from the POP3 server.

• Check whether or not the POP3 server is
faulty.

C146H

Could not close the POP3 server.

• Check whether or not the POP3 server is
faulty.
• Check whether or not there is too much load
on the network.

C147H

Closing the POP3 server gave an error
response.

• Check whether or not the POP3 server is
faulty.

C150H

POP3 server authentication error

• Check the status of the POP3 server.

C151H

The Ethernet module's mail address (e-mail
• Check the account name in the mailbox on
address setting parameter) is different from the
the server side and correct the mailbox
account set for the Ethernet module.
account name in the mailbox on the server side.

C152H

The Ethernet module's password (e-mail setting • Check the password on the server side and
parameter) is different from the password on the
correct the password set for the Ethernet
module.
server side.

C153H

An error occurred when getting the received
mail list.
(Failed to obtain the list of arrived mail at the
POP3 server.)

C13EH

11 - 27

(*1)

(*1)

• Check the status of the POP3 server.
• Send again after arbitrary set time has
passed.

11 - 27

11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23361
C160H
C161H

Received a response from the DNS server after
• Check whether or not there is too much load
timeout.
on the network.
Could not receive a response from the DNS
• Check the status of the DNS server.
server.

C162H

An error is returned from DNS server.

• Check if the DNS server's IP address setting
is correct or not.
• Check if the mail server name setting (SMTP
server name, POP server name) is correct or
not.
• Check with the network administrator or
similar person that the DNS function of the
server set in the DNS setting" is being
performed.

Multiple instructions for e-mail sending
• Mail sending instruction was issued while
sending a mail.

• Issue the instruction for sending a mail after
checking the mail send status.

C1A0H

An illegal request was made.

• Execute again.
If the same error occurs, the Ethernet
module's hardware may be faulty.
Consult your nearest branch office or dealer
with the details of the errors.

C1A2H

A response to a request could not be received.

• Review and correct the response wait time.

C1A5H

The designation of the target station or clear
target were incorrect.

• Correct the designated value of the target
station or clear target.

C1A6H

Incorrect connection number was designated.

• Designate the connection number within the
range of 1 to 4.

C1A7H

Incorrect network number was designated.

• Correct the designated value of the network
number.

C1ACH

Incorrect resent count was designated.

• Correct the designated value of the resent
count.

C1ADH

Incorrect data length was designated.

• Correct the designated value of the data
length.

C1AEH

Incorrect mail sending data length and header
length were designated.

• Correct the designated values of sending
data length and header length.
• Sending data length should be equal or
longer than the header length.

C1AFH

Incorrect port number was designated.

• Correct the designated value of the port
number.

C1B0H

The open processing of the designated
connection is already completed.

• Execute the open processing after executing
the close processing.

C1B1H

The open processing of the designated
connection has not been completed.

• Execute the open processing.

C1B2H

The OPEN/CLOSE instruction is being
executed in the designated connection.

• Execute after the OPEN/CLOSE instruction
is completed.

C1B3H

Another sending/receiving instruction is being
executed on the designated channel.

• Change the channel number.
• Execute after the sending/receiving
instruction is completed.

C1B6H

Incorrect mail destination number was
designated.

• Review the designated value of the mail
designation number.
• Review the sending mail address setting
parameter.

C203H

System error
• The OS detected any error.

(*1)

C206H

System error
• The OS detected any error.

(*1)

C163H

C171H
to
C17FH

C180H

11 - 28

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11 TROUBLESHOOTING

MELSEC-F

E-mail log

Error code

Connection

Error handling

Fixed
sending

Description of error

Open

Error code
(abnormal
code)

Initial

Storage destination

BFM# BFM# BFM# BFM# BFM# BFM#
105
124
125
126
229 23661
C281H

Improper usage setting of connections for fixed • Review and correct the set value for usage of
connections No. 1 and 2.
buffer

C282H

Improper usage setting of connections for
MELSOFT connection/MC protocol

• Review and correct the set value for usage of
connections No. 3 and 4.

C300 H

A response could not be received within the
response monitoring timer value.

• Check the operation of the external device.
• Review and correct the response monitoring
timer value.

*1

Take corrective action using the following procedure.
1) Check whether the expansion connectors are connected correctly.
2) Check whether the operating environment of the Ethernet module is within the general
specifications range of the module.
3) Check whether the power supply capacity is sufficient or not.
4) Check whether the hardware of the Ethernet module, power supply block and PLC are normal
according to the manuals of the corresponding modules.
If any module is faulty, please request your local Mitsubishi service center or representative to
have it serviced.
5) If the problem cannot be solved through the above steps, please consult your local Mitsubishi
service center or representative, explaining the operation/communication conditions at the time of
error occurrence and the information stored in the error log area within the buffer memory of the
Ethernet module.

NOTE
Depending on the restrictions of the buffers of the local station and external device,
data may be divided for communication.
Data received separately is restored (reassembled) by the Ethernet module to be
communicated using the fixed buffer, etc. The received data is restored
(reassembled) based on the data length in the communication data.
The Ethernet module performs the following processing if data among the
communication data is incorrect.

11 - 29

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11 TROUBLESHOOTING

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(1) When communication is performed using fixed buffer (with procedure)
(a) If the data length specified immediately after the subheader is smaller than
the amount of text data received
1) The data immediately following the part of the text data equivalent to the
data length specified immediately after the subheader will be regarded as
the next message.
2) Since the header of each message will be a subheader, the Ethernet
module performs processing according to the code in the subheader.
3) If the subheader contains a code that is not recognized by the Ethernet
module, the Ethernet module will send a response to the external device
notifying it of abnormal completion.
Data sent by an external device

Data determined by the Ethernet module
(First data)

Sub
Header

(Second data)

Sub
Header

This section is processed as a subheader.

At this point, the Ethernet module returns a response containing a code
obtained by changing the most significant bit of the code processed as
subheader to 1.
For example, if the subheader field of a command is 65H, the subheader of
the response will become E5H.
(b) If the data length specified immediately after the subheader is larger than the
amount of text data received
1) The Ethernet module waits for the reception of the remaining missing
data.
2) If the remaining data could be received within the time allotted by the
response monitoring timer, the Ethernet module performs processing
according to the code in the subheader.
3) If the remaining data could not be received within the time allotted by the
response monitoring timer, the Ethernet module performs the following
processing.
• Sends the ABORT (RST) instruction to the external device and closes
the line.
• Notifies the PLC side about occurrence of an open error via the open
error detection signal (BFM#28.b6=ON)
• Stores the error code in the open error code storage area. (The error
code is not stored in the error log storage area.)

POINT
Designate the actual data size of the text field for "data length" specified in the
application data field of a message sent from the external device to the Ethernet
module.
The Ethernet module never sends text whose size is different from the specified
data length to the external device.

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(2) When communication is performed using fixed buffer (non-procedure)
Since no message data length is specified in non-procedure communication, the
data received is stored in the receive buffer area as is.
It is recommended to set up some method of checking that the data is received
correctly. This can be achieved for instance by including the data length and data
type code in the application data of the message, so that the number of bytes and
type of application data can be identified on the receiving side.

11 - 31

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11 TROUBLESHOOTING

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11.5 Troubleshooting Flowchart
This section explains some simple troubleshooting procedures when the Ethernet
module and an external device have communication problems in a flowchart format. (*1)

POINT
If trouble occurs when using the Ethernet module, check the block status, error
status and others for the Ethernet module using the Ethernet diagnostic function of
FX Configurator-EN-L described in Subsection 11.2.2.
Data cannot be communicated.

Check whether or not an error
occurred in the PLC base unit to
which the Ethernet module is installed.

Did an error
that makes the PLC
stop processing
occur?

YES

Refer to the troubleshooting section
in the applicable PLC ’s user’s
manual and fix the problems.

NO
Check the status of the applicable
Ethernet module.

NO

Turn on the PLC and Ethernet module
again.
If the [RUN] LED does not turn on
even after resetting, the Ethernet
module’s hardware may be faulty.
Replace the Ethernet module and
restart all the external devices that
communicate with the local station.

Is the Ethernet module’s
[ERR.] LED on?

NO

Check whether or not a parameter
error occurred. If an error is found,
first correct it and then re-download.

Is the Ethernet module’s
[COM.ERR.] LED on?

NO

Is the connection cable
securely connected?

NO

Is the Ethernet module’s
[RUN] LED on?
YES

Is the data code
(binary/ASCII) setting of the
communication data
correct?
YES
1)

11 - 32

NO

Check the error contents using the
diagnostics function of
FX Configurator-EN-L.

Lock the cable securely.

Data cannot be sent/received
because the data code is different in
sending node and receiving node
and the command can therefore not
be successfully decoded.
Change the setting in
[Communicational data code] of
[Operational settings] using
FX Configurator-EN-L.
(See Section 4.6.) (*2)

11 - 32

11 TROUBLESHOOTING

MELSEC-F

1)

Is initial
processing normally completed
(BFM#27=
"0001H")

NO
(BFM#27=
"0001H")

YES

Perform initial processing.
(See Subsection 5.2.1.)
If the initial processing parameters set
with FX Configurator-EN-L and the
sequence program for initial processing
overlap, delete the sequence program
for initial processing.

Check and fix the faulty part for each
communication processing.

Sending error in fixed buffer communication
Receiving error in fixed buffer communication
Error in the MC protocol communication
Send error during communication by e-mail

See Subsection 11.5.1.
See Subsection 11.5.2.
See Subsection 11.5.3.
See Subsection 11.5.4.

*1 See Section 11.1 when the value of BFM#27 is "0000H" or when the display LED COM.ERR (communication error
detection display) lights up.
(Check an error code that is stored in the buffer memory in reaction to an error occurrence, then check the contents
of the error and take corrective actions by referring to Section 11.4.)
*2 Error codes not found in the error code list may be returned to the external device side if the communication data
settings on the Ethernet module side (see Section 4.6) and the data code settings on the external device side are
different.
The Ethernet module cannot decode commands correctly if data with different data codes is received. The Ethernet
module returns error responses according to the communication data code settings.

[example] When communication is performed using a fixed buffer.
Subheader

External device side
(Set to binary code)

Ethernet module side

Data length

The external device side
receives this portion
as an end code.

Subheader
Text

60H 00H
45H 30H 35H 34H

(Set to ASCII code)
Subheader

End code

*3 If the FG (
)terminals of the Ethernet module are not set, the communication line is closed (disconnected) due to
the effects of noise, and as a result communication with an external device may not be performed.

11 - 33

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11 TROUBLESHOOTING

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POINT
(1) When the Ethernet module is replaced due to an error, reboot the following
external devices and restart data communication:
(If the external device retains the Ethernet address, it may be impossible to
continue communication because when a module is replaced the Ethernet
address changes.)
In the same way, when the external device (personal computer, etc.) is
replaced, restart the Ethernet module.
• All external devices that communicated with the station whose Ethernet
module was replaced.
• All external devices that communicated with other station's PLC via a
station whose Ethernet module was replaced.
(2) When connecting a device to the Ethernet module, see the following sections
for the required devices and connection method:
Section 2.2: Devices Required for Network Configuration
Section 4.4: Connecting to the Network
(3) If the Ethernet module could not receive messages sent from external
devices frequently, check the values stored in the following buffer memory.
(a) Simultaneous transmission error detection count storage area (BFM#398
to 399) and Error/End code storage area for each error log block
(BFM#229...)
When the error detection count number is high or when the error code
C0C7H has been stored, high load may be applied to the Ethernet
connection line to transfer data among connected devices.
To reduce the load to the Ethernet line, it is necessary to take corrective
measures such as dividing the network or reducing the data transmission
frequency.
Consult your network administrator and take appropriate measures.

11 - 34

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11 TROUBLESHOOTING

MELSEC-F

11.5.1 Sending errors during fixed buffer communication
(common to procedure exist and no procedure)

Sending error

Check the open status of the
connection with an external device.

Are the
corresponding connection
LEDs (C1-C2) lit?

NO

Execute the open processing of the
applicable connection. (For details,
see Section 5.6.)

NO

Fix the error according to the error
code (see Section 11.4).

NO

Fix the error according to the error
code (see Section 11.4).

YES
If so, modify the program.
Read the open abnormal code (BFM
#229...) of the error log area and
check that no errors have occurred.

Have parameter
errors occurred?
YES
Read the content of the communication
abnormal code storage area (BFM
#125, 135) corresponding to the
fixed buffer of the buffer memory and
check whether or not a communication
error has occurred.

Has a communication
error occurred?
YES

Check that "send" is set in the
parameter open settings.

Are the open
1) settings
set to "send"?

NO

Change parameters to "send".

YES

Is the parameter,
IP address of the external device,
correct?

NO

Correct the IP address of the external
device.

YES
1)

11 - 35

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11 TROUBLESHOOTING

MELSEC-F

1)

Does the
communication protocol
(TCP/UDP) match that of
the external device?

NO

Match the protocol with the
communication protocol (TCP/UDP) of
the external device. (For details, see
Section 5.5.)

YES

Was the "0001H" written to
from BFM#1610, 1611?

NO

Correct the write condition of
BFM#1610, 1611.

NO

Check the fixed buffer transfer error
code of BFM#125, 135

YES
Is the read value of
BFM#1610, 1611 "0004H"?

YES
Is the word
count (procedure) or byte
count (non-procedure) set at the
head of the fixed
buffer?

NO

Write the data length.

YES
Check the communication status of
the external device.

Does the external
device operate normally?

NO

Fix the faulty part of the external
device. (If the receiving side is also an
Ethernet module, see Section 11.4.)

YES
Are there any
open errors or initial errors
in the error log area?

NO

Check and fix the faulty part.

YES
The Ethernet module hardware on the
sending side may be faulty.
Consult your nearest branch office or
dealer with the details of the errors.

POINT
If the external device communicates normally, the following conditions occur.
For TCP communication
When the external device's open status is complete, LEDs C1, C2, which are in
correspondence with connections 1, 2, turn on.
For UDP communication
When external device communication is possible, LEDs C1, C2, which are in
correspondence with connections 1, 2, turn on.
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11 TROUBLESHOOTING

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11.5.2 Receiving errors during fixed buffer communication
(common to procedure exist and no procedure)
POINT
Perform error code reading while the connection is open.

Receiving error

Do the expected length
of data to be received and
the amount of data actually
received match?

NO

If the amount of actually received data is
smaller than the length of data expected to
be received, the subsequent processing
must allow reception of the remaining data.
If the amount of actually received data is
larger than the length of data expected to
be received, the subsequent data should
be treated as the next request message or
as unnecessary data.
(See NOTE in 11.4.4 section for further
details.)

YES
Check the open status of the
connection with an external device.

Are the corresponding
connection LEDs (C1, C2 ) lit?

NO

Execute the open processing of the
applicable connection.
(For details, see Section 5.6.)

YES
Read the open abnormal code (BFM
#124, 134) of the communication status
storage area and check that no errors
have occurred.

Have parameter errors
occurred?

NO

Fix the error according to the parameter
error code (see Section 11.4).

NO

Fix the error according to the
communication error code in the error log
area (see Section 11.4).

YES
Read the content of the communication
abnormal code storage area (BFM #125,
135) corresponding to the fixed buffer
of the buffer memory and check whether
or not a communication error has occurred.

Has a
communication error occurred in the
error log area?
YES
Check that "receive" is set in the parameter
open settings.

1) is set
Receive

NO

Change parameters to "receive".

YES

1)

11 - 37

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11 TROUBLESHOOTING

MELSEC-F

1)

Is the parameter
for IP address of the
external device correct?
Is each Port No.
of the local and the
external station
correct?

NO

Correct the IP address of the external
device.

YES
Does the communication
protocol (TCP/UDP) match with that
of the external device?

Match the protocol with the
communication protocol (TCP/UDP)
of the external device.
(For details, see Section 5.5.)

NO

YES
Is the receive
completion signal
(corresponding bit of BFM#20485)
of the applicable fixed buffer on?
Is the value of BFM#1610,
1611 set to
0001H?

NO

YES

Data may not have been set from the
external device.
Check the sending side.
(If the sending side is also an
Ethernet module, see Section 11.4.)

Did the error
occur in the device on the
sending side?

YES

NO
Fix the faulty part of the device on
sending side.

The Ethernet module on receiving
side may be faulty. Consult your
nearest branch office or dealer with
the details of the errors.
NO

Is "0002H" written to
BFM#1610, 1611?

YES

Change the condition for writing
"0002H" to BFM#1610, 1611.

Check the communication status
of the device on the sending side.

NO

Does the external device
operate normally?

YES

Check the device on the sending
side. (If the sending side is also an
Ethernet module, see Section 11.4.)

The Ethernet module hardware on
the sending side may be faulty.
Consult your nearest branch office or
dealer with the details of the errors.

11 - 38

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11 TROUBLESHOOTING

MELSEC-F

POINT
If the external device communicates normally, the following conditions occur.
For TCP communication
When the external device's open status is complete, LEDs C1, C2, which are in
correspondence with connections 1, 2, turn on.
For UDP communication
When external device communication is possible, LEDs C1, C2, which are in
correspondence with connections 1, 2 turn on.

11 - 39

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11 TROUBLESHOOTING

MELSEC-F

11.5.3 Errors in communication using MC protocol
Communication error

Check the open status of the
connection with the external device.

Are the corresponding connection LEDs
(C3, C4) lit?

NO

Execute the open processing of the
applicable connection. (For details,
see Section 5.6.)

NO

Send the command to the Ethernet
module.

YES
Was a command sent
form the external device?
YES
Was a response
returned to the device that sent
the command?

NO

Is the IP address
designation of the command
correct?

YES

NO

Correct the IP address and send
the command again.

NO

Match the communication protocol
(TCP/UDP) with the external device.
(For details, see Section 5.5.)

YES
Does the
communication protocol
(TCP/UDP) match with that of the
external device?
YES
The command may not be sent to the
Ethernet module from the external
device on the command sending
side. Check the sending side.

Is the end code of
the response "0"?

NO

Fix the faulty part according to
the description of the end and
abnormalcodes (see Section 11.4).

YES
1)

11 - 40

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11 TROUBLESHOOTING

MELSEC-F

1)

Is the IP address of the
command correct?

NO

Correct the IP address and send the
command again.

YES

Are the
command formats,
such as command type, device
designation, and address
designation, designated
correctly?

NO

Correct the command format.

YES
Are there any open
errors or initial errors in the error
log area?

NO

Check and fix the faulty part.

YES
The Ethernet module hardware may
be faulty. Consult your nearest dealer
with the details of the errors.

POINT
• If the external device communicates normally, the following conditions occur.
For TCP communication
When the external device's open status is complete, LEDs C3, C4, which are
in correspondence with connections 3, 4, turn on.
For UDP communication
When external device communication is possible, LEDs C3, C4, which are in
correspondence with connections 3, 4, turn on.
• In connections used for communication using MC protocol, it is necessary to set
the communication parameter to "MC protocol usable" in "Connection usage" as
described in the table in Subsection 5.5.2, or select "Unpassive open (MC)" or
"Fullpassivel open (MC)" in the open system settings in FX Configurator-EN-L .

11 - 41

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11 TROUBLESHOOTING

MELSEC-F

11.5.4 Sending errors during e-mail communication

Sending error

Is "0001H" written to
BFM#10333?

NO

Correct the condition for writing to
BFM#10333.

YES

Is the value of
BFM#10334 set to "0001H"?

NO

YES
Are the mail server
port numbers set correctly in
BFM#24320 and 24388?

NO

Set the server port numbers correctly.
YES

Is the SMTP authentication
setting used?

NO

YES
When "SMTP-AUTH" is selected,
check whether the SMTP login ID and
password are set correctly.
When "POP before SMTP" is selected,
check whether the POP password and
local mail address are set correctly.

Can the error
response be received from
the mail server using the mail
receiving operation?

NO

YES

Confirm with the system administrator
that the following are set correctly:
DNS settings
E-mail settings

Modify the contents of error based on
the e-mail sending error log
(Refer to Section 11.4).

Check the following items.
E-mail parameter settings of the
Ethernet module
Whether or not the mail server's
system is down
Whether or not there is an error
on the communication path

11 - 42

11 - 42

APPENDIX

MELSEC-F

APPENDIX
Appendix 1 Processing Time
Calculate the minimum processing time for each function using the expressions below.
Note that the processing time may become longer depending on the load factor on the
network (how congested the line is), the window size of each connected device, the
number of connections used concurrently, and how the system is configured. Use the
values obtained from the expressions below as a guideline for the processing time
when communication is performed using only one connection.

(1) Minimum processing time of communication using the fixed buffer
(communication between the Ethernet module)
(a) Communication using the fixed buffer (Procedure exist)
Tfs = St + Ke + (Kdf

Df) + Sr

Tfs

: Time from the start of sending to the completion of sending
(unit: ms)

St

: Sending station scan time

Ke, Kdf

: Constant (see the table below)

Df

: Word count of send data

Sr

: Receiving station scan time
Communication using TCP/IP

Communication using UDP/IP

Ke

Kdf

Ke

Kdf

Data communication using binary code

12

0.0065

10

0.0069

Data communication using ASCII code

12

0.030

10

0.029

(b) Communication using the fixed buffer (No procedure)
Tfs = St + Ke + (Kdf Df)
Tfs

: Time from the start of sending to the completion of sending
(unit: ms)

St

: Sending station scan time

Ke, Kdf

: Constant (see the table below)

Df

: Byte count of send data
Communication using TCP/IP

Data communication using binary code

Communication using UDP/IP

Ke

Kdf

Ke

Kdf

7

0.0018

4

0.0014

[Calculation example]
Calculate the time from the start of sending to the completion of sending
(unit: ms) when the FX3U-ENET-L communicate using TCP/IP and send
32 words of binary code data using fixed buffer communication
(procedure exist).
• Assume that the scan time on the receiving side is 30 ms and the
scan time on the transmission side is 25 ms:
67 (ms) 30 + 12 + (0.0065 32) + 25

App - 1

App - 1

App

APPENDIX

MELSEC-F
(2) Minimum processing time of communication using MC protocol
(batch read and batch write)
Tfs = Ke + (Kdt Df) + Scr number of scans required for processing +
ACK processing time of external device
Tfs

App

: Time from when Ethernet module receives request data
from personal computer until it completes processing (unit:
ms) *1

*1

Ke, Kdt

: Constant (refer to the table below)

Df

: Number of request data words + number of response data
words (Application data part)

Scr

: Scan time

The timing sequence from when the Ethernet module receives the
request data from the personal computer until it completes processing is
shown below.
External device
(personal computer)
Command
message

Response
message

ACK
(TCP only)

ACK
(TCP only)

Ethernet module
END

Step 0

Step 0

END

PLC scan time
Tfs

Communication using TCP/IP

Communication using UDP/IP

Ke

Kdt

Ke

Kdt

Batch
read

Data communication using binary code

14

0.009

13

0.008

Data communication using ASCII code

18

0.015

13

0.017

Batch
write

Data communication using binary code

14

0.009

13

0.008

Data communication using ASCII code

16

0.027

14

0.027

App - 2

App - 2

APPENDIX

MELSEC-F
[Calculation example 1]
Calculate the required time (unit: ms) to complete the processing of a
data request from a PC after receiving it, when the Ethernet module and
the PC perform TCP/IP communication and read 32 points of ASCII
code data from the data register (D) in the PLC using MC protocol
communication.
• Assume that the scan time of the FX3U-ENET-L installed station is 40
ms:
59.17 + ACK processing time of the external device (ms)
18 + (0.015 (12 + 66)) + 40 1 + ACK processing time of the
external device
Command data length = 12 words
Response data length = 66 words
[Calculation example 2]
Calculate the required time (unit: ms) the FX3U-ENET-L takes to
complete the processing of a data request from a PC after receiving it,
when the Ethernet module and the PC performs TCP/IP communication
and writes 32 points of ASCII code data to the data register (D) in the
PLC using MC protocol communication.
• Assume that the scan time of the FX3U-ENET-L installed station is 40
ms:
58.11 (ms) 16 + (0.027 (76 + 2)) + 40 1
Command data length = 76 words
Response data length = 2 words

App - 3

App - 3

APPENDIX

MELSEC-F

Appendix 2 ASCII Code List
MSD
LSD

0

1

2

3

4

5

6

7

000

001

010

011

100

101

110

111

0

0000

NUL

DLE

(SP)

0

@

P

`

p

1

0001

SOH

DC1

!

1

A

Q

a

q

2

0010

STX

DC2

“

2

B

R

b

r

3

0011

ETX

DC3

#

3

C

S

c

s

4

0100

EOT

DC4

$

4

D

T

d

t

5

0101

ENQ

NAK

%

5

E

U

e

u

6

0110

ACK

SYN

&

6

F

V

f

v

7

0111

BEL

ETB

’

7

G

W

g

w

8

1000

BS

CAN

(

8

H

X

h

x

9

1001

HT

EM

)

9

I

Y

i

y

A

1010

LF

SUB

:

J

Z

j

z
{

B

1011

VT

ESC

+

;

K

[

k

C

1100

FF

FS

,

<

L

\

l

|

D

1101

CR

GS

—

=

M

]

m

}

E

1110

SO

RS

.

>

N

^

n

~

F

1111

SI

US

/

?

O

_

o

DEL

Appendix 3 References
For details on TCP/IP, refer to the DDN Protocol Handbook (3 volumes).
Publisher
DDN Network Information Center
SRI International
333 Ravenswood Avenue, EJ291
Menlo Park, California 94025
RFC Number
TCP
RFC793
UDP
RFC768
IP
RFC791
ICMP RFC792
ARP
RFC826

App - 4

App - 4

APPENDIX

MELSEC-F

Appendix 4 Program Examples
The program examples presented in this section test the connection between the
Ethernet module and an external device (personal computer) that is connected to the
same Ethernet.
For each program, only the minimum programming that is required to perform the
communication test is done. Modify the IP address, port number and other values
according to your system configuration. In addition, abnormal handling may be added.

(1) Receive processing of target device
A receive processing example on the target device side is shown below.
Communication processing
on the external device side

Request message/transmission processing

Response message/reception processing

The TCP connection is closed
Is the TCP connection open?

Receive remaining
response messages

Was the reception data
received within the time allotted
by the monitoring timer?

Timeout of monitoring timer

Insufficient size
of data received
Check the size of the received data

If a response message to the
next request was received
Response message processing

Have all the received
messages been processed?

End

Error handling

Background
For Ethernet communications, the TCP socket functions are used inside the
personal computer. However, these functions do not have any limits. Therefore,
when the "send" function is executed once to transmit data, the receiving end (node)
needs to execute the "recv" function once or more in order to read the data ("send"
and "recv" is not proportional to 1:1 execution). For this reason, the receiving
procedure explained above, is required.
App - 5

App - 5

APPENDIX

MELSEC-F

Appendix 4.1 Program example for communication using MC protocol -1
The following explains a program, its execution environment and the contents of data
communication .

(1) Execution environment of the program example
(a) PLC side
1) Base module of the Ethernet installed station

: FX3U/FX3UC

2) Ethernet module No.

: No.1

3) Ethernet module IP address

: 172.16.56.99 (AC.10.38.63H)

4) Ethernet module port number

: 10000

5) FX Configurator-EN-L setting
• Operational settings

: See "(3) FX Configurator-EN-L setting
(a)" on the next page

• Open settings

: See "(3) FX Configurator-EN-L setting
(b)" on the next page

(b) External device side
1) Operation environment

: Microsoft Windows 2000
Operating system

2) Ethernet interface board model name

: WINSOCK compatible board

3) Library

: WSOCK32.LIB

4) Software development environment

: Microsoft Corporation Visual
C++ .NET

5) Ethernet address

: Setting not required because
the ARP function is available

6) IP address

: Receive at Active open

7) Port number

: Receive at Active open

(c) Communication protocol

: TCP/IP

(2) Outline of the program example
(a) Sequence program on the PLC side
Parameters are set from FX Configurator-EN-L.
(Sequence program is not required)
(b) Program on the external device side
Executes the following read/write data communication with the PLC using
the library mentioned above.
• Write in word units (for 5 points from D0 to D4)
• Read in word units (for 5 points from D0 to D4)

App - 6

App - 6

APPENDIX

MELSEC-F
(3) FX Configurator-EN-L settings
Set the PLC parameters as follows.
(a) Operation settings
Communication data code

: ASC II

Initial timing

: Always wait for OPEN (Communication
possible at STOP time)

IP address

: 172.16.56.99 (AC.10.38.63H)

(b) Open settings

App - 7

Protocol

: TCP

Open system

: Unpassive (MC)

Existence confirmation

: No confirm

Local station Port No.

: 10000

App - 7

APPENDIX

MELSEC-F
(4) Program on the external device side
The program example of the external device shown below accesses the FX3U of
the station in which the Ethernet module is installed.
When this program is executed, the contents of the following communication
messages are displayed in sequence:
1) Batch write command message in word units
2) Batch write response message in word units
3) Batch read command message in word units
4) Batch read response message in word units

REMARK
(1) The following explains an outline of the compiling procedure for a program
created using Microsoft Corporation Visual C++ .NET
1) Start Visual C++ .
2) Prepare for program creation.
Select "New Project" from the project tab, select "Win32 console project",
and create an empty project with the name "ENETSAMP".
3) Add ENETSAMP.C to the project and create a program.
(See the program example on the next page.)
4) Compile the created file from the compile screen of the build menu.
5) From the project menu property setting screen, add WSOCK32.LIB to the
linker addition dependency files.
6) Create an executable file (ENETSAMP.EXE) on the build screen of the build
menu.
7) End Visual C++ .NET.
8) Execute ENETSAMP.EXE.

(2) Outline of the procedure for calling the socket routine
Start

(Create socket)

socket()

bind()
(Bind)

(Open)

Passive open

Active open

listen()

UDP

connect()

accept()

(Communicate)

(Disable sending/receiving)
(Close)

send()/recv()

sendto()/recvfrom()

shutdown()
closesocket
Complete

App - 8

App - 8

APPENDIX

MELSEC-F

/ ***************************************************************** /
** /
/ **
/ **
** /
Sample program
/ **
** /
/ **
** /
This program is a sample program to conduct a ** /
/ **
connection test between the Ethernet block and ** /
/ **
/ **
** /
target device.
/ **
** /
This program accesses the data register (D) of
/ **
** /
the Base Module installed together with the
/ **
** /
Ethernet block.
/ **
** /
/ **
** /
** /
/ **
Copyright(C) 2009 Mitsubishi Electric
** /
/ **
Corporation
** /
/ **
All Rights Reserved
** /
/ **
/ ***************************************************************** /

#include 
#include 
#define FLAG_OFF 0
// Completion flag OFF
#define FLAG_ON 1
// Completion flag ON
#define SOCK_OK 0
// Normal completion
#define SOCK_NG -1
// Abnormal completion
#define BUF_SIZE 4096
// Receive buffer size
#define ERROR_INITIAL 0
// Initial error
#define ERROR_SOCKET 1
// Socket creation error
#define ERROR_BIND 2
// Bind error
#define ERROR_CONNECT 3
// Connection error
#define ERROR_SEND 4
// Send error
#define ERROR_RECEIVE 5
// Receive error
#define ERROR_SHUTDOWN 6
// Shutdown error
#define ERROR_CLOSE 7
// Line close error
//Definitions for checking the receiving sizes
//#define RECV_ANS_1 4
// Receiving size of response message in reply to device write (1E frame)
//#define RECV_ANS_2 24
// Receiving size of response message in reply to device read (1E frame)
typedef struct sck_inf{
struct in_addr my_addr;
unsigned short my_port;
struct in_addr FX_IP_addr;
unsigned short FX_port;
};
int nErrorStatus;
int Dmykeyin;
int Closeflag;
SOCKET socketno;

App - 9

// Error information storage variable
// Dummy key input
// Connection completion flag

App - 9

APPENDIX

int main()
{
WORD wVersionRequested=MAKEWORD(1,1);
WSADATA wsaData;
int length;
unsigned char s_buf[BUF_SIZE];
unsigned char r_buf[BUF_SIZE];
int rbuf_idx;
int recv_size;
struct sck_inf sc;
struct sockaddr_in hostdata;
struct sockaddr_in FX3UENET_L;
void Sockerror(int);
unsigned long ulCmdArg ;

MELSEC-F

// Winsock Ver 1.1 request
// Communication data length
// Send buffer
// Receive buffer
// Receive data storage head index
// Number of receive data
// External device side data
// Ethernet block side data
// Error handling function
// Non-blocking mode setting flag

sc.my_addr.s_addr=htonl(INADDR_ANY);
sc.my_port=htons(0);
sc.FX_IP_addr.s_addr=inet_addr("172.16.56.99");

// External device side IP address
// External device side port number
// Ethernet block side IP address
// (AC103863h)
sc.FX_port=htons(10000);
// Ethernet block side port number
Closeflag=FLAG_OFF;
// Connection completion flag off
nErrorStatus=WSAStartup(wVersionRequested,&wsaData); // Winsock Initial processing
if (nErrorStatus!=SOCK_OK) {
Sockerror(ERROR_INITIAL);
// Error handling
return (SOCK_NG);
}
printf ("Winsock Version is %ld.%ld\n",HIBYTE(wsaData.wVersion),LOBYTE(wsaData.wVersion));
printf ("FX3U-ENET-L Test Start\n");
socketno=socket(AF_INET,SOCK_STREAM,0);
// Create socket for TCP/IP
if (socketno==INVALID_SOCKET){
Sockerror (ERROR_SOCKET);
// Error handling
return(SOCK_NG);
}
hostdata.sin_family=AF_INET;
hostdata.sin_port=sc.my_port;
hostdata.sin_addr.s_addr=sc.my_addr.s_addr;
if(bind(socketno,(LPSOCKADDR)&hostdata,sizeof(hostdata))!=SOCK_OK){
// Bind
Sockerror(ERROR_BIND);
// Error handling
return(SOCK_NG);
}
FX3UENET_L.sin_family=AF_INET;
FX3UENET_L.sin_port=sc.FX_port;
FX3UENET_L.sin_addr.s_addr=sc.FX_IP_addr.s_addr;
if(connect(socketno,(LPSOCKADDR)&FX3UENET_L,sizeof(FX3UENET_L))!=SOCK_OK){
// Connection (Active open)
Sockerror(ERROR_CONNECT);
// Error handling
return(SOCK_NG);
}

App - 10

App - 10

APPENDIX

MELSEC-F

Closeflag=FLAG_ON;
// Connection completion flag ON
// Go to non-blocking mode
ulCmdArg = 1;
ioctlsocket(socketno, FIONBIO, &ulCmdArg);
// Set to non-blocking mode
strcpy(s_buf, "03FF000A4420000000000500112233445566778899AA");
// D0 to D4 batch write request (1E frame)
length=(int)strlen(s_buf);
if(send(socketno,s_buf,length,0)==SOCKET_ERROR){
// Data sending
Sockerror(ERROR_SEND);
// Error handling
return (SOCK_NG);
}
printf("\n send data\n%s\n",s_buf);
// Perform receiving size check and receiving processing simultaneously
rbuf_idx = 0;
// Receive data storage head index initialization
recv_size = 0;
// Initialize the number of receive data
while(1) {
length = recv(socketno, &r_buf[rbuf_idx], (BUF_SIZE - rbuf_idx), 0);
// Response data receiving
if(length == 0) {
// Is connection cut off?
Sockerror(ERROR_RECIEVE);
// Error handling
return (SOCK_NG);
}
if(length == SOCKET_ERROR) {
nErrorStatus = WSAGetLastError();
if(nErrorStatus != WSAEWOULDBLOCK) {
Sockerror(ERROR_RECIEVE);
return (SOCK_NG);
} else {
continue;
}
} else {
rbuf_idx += length;
recv_size += length;
if(recv_size >= RECV_ANS_1)
break;
}
}
r_buf[rbuf_idx] = '\0' ;
printf("\n receive data\n%s\n",r_buf);
strcpy(s_buf, "01FF000A4420000000000500");

// Error handling
// Repeat until messages are received
// Update the receive data storage
// position
// Update the number of receive data
// Have all response messages been
// received?
// Stop repeating as messages have
// been received
// Set NULL at the end of receive data
// D0 to D4 batch read request
// (1E frame)

length=(int)strlen(s_buf);
if(send(socketno,s_buf,length,0)==SOCKET_ERROR){
// Data sending
Sockerror(ERROR_SEND);
// Error handling
return (SOCK_NG);
}
printf("\n send data\n%s\n",s_buf);
// Perform receiving size check and receiving processing simultaneously
rbuf_idx = 0;
// Receive data storage head index
// initialization
recv_size = 0;
// Initialize the number of receive data

App - 11

App - 11

APPENDIX

MELSEC-F

while(1) {
length = recv(socketno, &r_buf[rbuf_idx], (BUF_SIZE - rbuf_idx), 0);
// Response data receiving
if(length == 0) {
// Is connection cut off?
Sockerror(ERROR_RECIEVE);
// Error handling
return (SOCK_NG);
}
if(length == SOCKET_ERROR) {
nErrorStatus = WSAGetLastError();
if(nErrorStatus != WSAEWOULDBLOCK) {
Sockerror(ERROR_RECIEVE);
return (SOCK_NG);
} else {
continue;
}
} else {
rbuf_idx += length;
recv_size += length;
if(recv_size >= RECV_ANS_2)
break;
}
}
r_buf[rbuf_idx] = '\0' ;
printf("\receive data\n%s\n", r_buf);
if(shutdown(socketno,2)!=SOCK_OK){
Sockerror(ERROR_SHUTDOWN);
return(SOCK_NG);

// Error handling
// Repeat until messages are received
// Update the receive data storage
// position
// Update the number of receive data
// Have all response messages been
// received?
// Stop repeating as messages have
// been received
// Set NULL at the end of receive data
// Processing to disable
// sending/receiving
// Error handling

}
if(closesocket(socketno)!=SOCK_OK){
// Close processing
Sockerror(ERROR_CLOSE);
// Error handling
return(SOCK_NG);
}
Closeflag=FLAG_OFF;
// Connection completion flag off
WSACleanup();
// Release Winsock.DLL
printf("\nFX3U-ENET-L Test End.\n\n Normally completed. \n");
printf("Press any key to exit the program.\n");
Dmykeyin=getchar();
// Wait for key input
return(SOCK_OK);
}
void Sockerror(int error_kind)
{
if(error_kind==ERROR_INITIAL){
printf("Initial processing is abnormal.");
}
else{
nErrorStatus=WSAGetLastError();
switch(error_kind){
case ERROR_SOCKET:
printf("Failed to create socket.");
break;
App - 12

// Error handling function

App - 12

APPENDIX

MELSEC-F
case ERROR_BIND:
printf("Failed to bind.");
break;
case ERROR_CONNECT:
printf("Failed to establish connection.");
break;
case ERROR_SEND:
printf("Sending failed.");
break;
case ERROR_RECIEVE:
printf("Receiving failed.");
break;
case ERROR_SHUTDOWN:
printf("Failed to shutdown.");
break;
case ERROR_CLOSE:
printf("Failed to close normally.");
break;
}

}
printf("Error code is %d.\n", nErrorStatus);
if(Closeflag==FLAG_ON){
nErrorStatus=shutdown(socketno,2);
nErrorStatus=closesocket(socketno);
Closeflag=FLAG_OFF;
}
printf("Press any key to exit the program.\n");
Dmykeyin=getchar();
WSACleanup();
return;

// Shutdown processing
// Close processing
// Connection completion flag off
// Wait for a key input
// Release Winsock.DLL

}

App - 13

App - 13

APPENDIX

MELSEC-F

Appendix 4.2 Program example for communication using MC protocol -2
This section explains an example of an external device program that reads/writs data
from the PLC.
A sample program, its execution environment and contents of data communication
are shown below.

(1) Execution environment of the program example
1) The settings of the PLC side are the same as those of the execution
environment described in Section 4.1 (1) (a) and (3) of Appendix.
2) The settings of the external device side are the same as those of the
execution environment described in Section 4.1 (1) (b) of Appendix,
except for the following including the software development:
• Software development environment:Microsoft Corporation Visual
Basic .NET
• Arbitrary numbers are assigned for the IP address and port number.
3) The communication protocol is TCP/IP

(2) Outline of the program example
With the A-compatible 1E frame command (01: batch read in word units), this
program reads data from D0 to D4 (five points) of the PLC of the station on which
the Ethernet module is mounted.

(3) Outline of the sample program
(a) Create a new project and form.
(b) Create the (example) window shown in (4) below using " Button" and "List
Box" in the toolbox.
(c) Create the program shown in (5).

App - 14

App - 14

APPENDIX

MELSEC-F
(4) Window example (Form 1)
(Object name)
Start
Connect to the Ethernet module
and perform communications
1st Output
Display data that was read from
the Ethernet module

(5) Sample program (Form 1)
Parts in italic are created automatically by Visual Basic .NET, so no input is required.
Only input where written in bold.
Option Explicit On
Option Strict On
Imports System.Net.Sockets
Public Class Form1
Inherits System.Windows.Forms.Form
#Region " Windows Code created by Form Designer "
Public Sub New()
MyBase.New()
' This call is necessary for Windows Form Designer.
InitializeComponent()
' InitializeComponent() Initialization is added after the call.
End Sub
' The Form overwrites dispose to execute after-processing in the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
' Necessary for Windows Form Designer.
Private components As System.ComponentModel.IContainer

App - 15

App - 15

APPENDIX

MELSEC-F

Memo: The following procedure is necessary for Windows Form Designer.
Change by using Windows Form Designer.
Do not use code editor to change.
Friend WithEvents Start As System.Windows.Forms.Button
Friend WithEvents lstOutput As System.Windows.Forms.ListBox
 Private Sub InitializeComponent()
Me.Start = New System.Windows.Forms.Button
Me.lstOutput = New System.Windows.Forms.ListBox
Me.SuspendLayout()
'
'Start
'
Me.Start.Location = New System.Drawing.Point(16, 16)
Me.Start.Name = "Start"
Me.Start.Size = New System.Drawing.Size(88, 32)
Me.Start.TabIndex = 0
Me.Start.Text = "Start"
'
'lstOutput
'
Me.lstOutput.ItemHeight = 12
Me.lstOutput.Location = New System.Drawing.Point(16, 64)
Me.lstOutput.Name = "lstOutput"
Me.lstOutput.Size = New System.Drawing.Size(264, 196)
Me.lstOutput.TabIndex = 1
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 12)
Me.ClientSize = New System.Drawing.Size(296, 273)
Me.Controls.Add(Me.lstOutput)
Me.Controls.Add(Me.Start)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
#End Region
Private Sub Start_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
Start.Click
Dim IpAddress As String
Dim PortNum As Integer
Dim Client As TcpClient
Dim Buffer() As Byte
Dim InBuff(1532) As Byte
Dim TxCommand As String

App - 16

App - 16

APPENDIX

MELSEC-F

Dim RxResponse As String
Dim Temp As String
Dim j As Integer
Dim Dreg(5) As Double
Dim DregStr$
Dim SubHeader$
' IP Address specification
IpAddress = "172.16.56.99"
' Port Number specification
PortNum = 10000
Client = New TcpClient
'Line connection processing
Try
Client.Connect(IpAddress, PortNum)
Catch ex As Exception
MsgBox("Connection with the server failed, and the following code was returned:
"& ex.Message, 0, "connection error")
Exit Sub
End Try
'Read D0 to D4 (5 points) with the A-compatible 1E frame command.
TxCommand = "01ff000a4420000000000500"
Buffer = System.Text.Encoding.Default.GetBytes(TxCommand.ToCharArray)
'Sending a read command
Client.GetStream().Write(Buffer, 0, Buffer.Length)
'Waiting for a response from an Ethernet block
While Not Client.GetStream().DataAvailable()
Application.DoEvents()
End While
If Client.GetStream().DataAvailable() Then
Client.GetStream().Read(InBuff, 0, InBuff.Length)
RxResponse = System.Text.Encoding.Default.GetString(InBuff)
SubHeader = Mid$(RxResponse, 3, 2)
If SubHeader = "00" Then 'Normal response
Temp = ""
'Initialization of an output character string
For j = 0 To 4
DregStr$ = Mid(RxResponse, j * 4 + 5, 4)
Dreg(j) = Val("&H" + DregStr$)
Temp = Temp + Format(Dreg(j), "#####0") + " "
Next
lstOutput.Items.Insert(lstOutput.Items.Count, Temp)
ElseIf SubHeader = "5B" Then
' In an abnormal response, an abnormal code is added.
Temp = "Terminate Code = " & SubHeader & " Error Code = " & Mid$(RxResponse, 5, 2)
lstOutput.Items.Insert(lstOutput.Items.Count, Temp)
Else
Temp = "Terminate Code = " & SubHeader
lstOutput.Items.Insert(lstOutput.Items.Count, Temp)
App - 17

App - 17

APPENDIX

MELSEC-F

End If
lstOutput.SelectedIndex = lstOutput.Items.Count - 1
End If
' Line disconnection processing
Client.GetStream().Close()
Client.Close()
End Sub
End Class

App - 18

App - 18

APPENDIX

MELSEC-F

Appendix 5 Differences between the Ethernet and the IEEE802.3
The following shows the Ethernet header in the data link layer supported by the
Ethernet module.
Ethernet data link layer header

Ethernet module

Ethernet frame (V 2.0) specification
IEEE802.3 (ISO/IEC8802.3) frame specification

(1) Ethernet

Destination address

Source address

Type

Data (46 to 1500 bytes)

FCS

Source address

Length

Data (46 to 1500 bytes)

FCS

(2) IEEE802.3

Destination address

Appendix 6 ICMP Protocol Supported by the Ethernet Module
The following table outlines the types of ICMP supported by the Ethernet module and
the processing performed by the Ethernet module.
ICMP Type

ICMP name/description

0

Echo Reply
Result of IP packet loopback

8

Echo Request
Requests loopback of IP packet

Others

—

Processing by the Ethernet module
Upon receiving an Echo Request, the Ethernet module
sends this message.
If destination existence confirmation is set in the buffer
memory, the Ethernet module sends this message when
attempting to confirm the existence of the target. (*1)
Ignored by the Ethernet module. (Not supported)

*1 The Ethernet module can simultaneously receive two ICMP ECHO requests (type 8, Ping message), which are used for
existence confirmation, etc., and handles them accordingly.
When three or more ICMP ECHO requests are received at the same time, the third and succeeding requests will be
ignored.
If a response is not returned to the external device when an ICMP ECHO request is sent to the Ethernet module, send
an ICMP ECHO request to the Ethernet module again.
The Ethernet module is able to receive a maximum of 1460 bytes ICMP message at one time.
Do not send an ICMP message request exceeding 1460 bytes to the Ethernet module.

App - 19

App - 19

APPENDIX

MELSEC-F

Appendix 7 Setting Value Recording Sheets
This section provides setting value recording sheets for parameters set with
FX Configurator-EN-L Make copies as needed.
Setting value recording sheet No.

FX Configurator-EN-L setting screen

Recording sheet 1

Ethernet operations

Recording sheet 2

Ethernet initial settings

Recording sheet 3

Ethernet open settings

Recording sheet 4
Recording sheet 5

Setting the Ethernet relay parameter
Ethernet E-mail settings
Ethernet mail address settings

Recording sheet 1
[Block number

]

FX Configurator-EN-L
setting screen

Setting data

Data item

Setting value

Communication data code setting

Initial Timing

Ethernet Operations

IP address
setting

Send frame setting
TCP Existence
Confirmation setting

App - 20

ASCII code communication
Do not wait for OPEN (Communications impossible at
STOP time)
Always wait for OPEN (Communication possible at STOP
time)
Decimal

Input format

IP address

Remark

Binary code communication

IP address
Input format

Hexadecimal

.

.

.

Adjust to input format

Ethernet (V2.0)
IEEE802.3
Use the KeepAlive
Use the Ping

App - 20

APPENDIX

MELSEC-F

Recording sheet 2
[Block number

]

FX Configurator-EN-L
setting screen

Setting data

Data item

Timer setting

Ethernet Initial settings

Setting value

TCP ULP Timer

initial: 60 (unit: 500 ms)

TCP zero
window Timer

initial: 20 (unit: 500 ms)

TCP resend timer

initial: 20 (unit: 500 ms)

TCP end timer

initial: 40 (unit: 500 ms)

IP assembly timer

initial: 10 (unit: 500 ms)

Response monitoring
timer

initial: 60 (unit: 500 ms)

Destination existence
confirmation
starting interval

initial: 1200 (unit: 500 ms)

Destination existence
confirmation
Interval timer

initial: 20 (unit: 500 ms)

Destination existence
confirmation resend
timer

initial: 3 (times)
Decimal

Input format

DNS setting

App - 21

Remark

DNS server IP address
Input format

Hexadecimal

DNS server 1
IP address

.

.

.

DNS server 2
IP address

.

.

.

DNS server 3
IP address

.

.

.

DNS server 4
IP address

.

.

.

Adjust to input format

App - 21

APPENDIX

MELSEC-F

Recording Sheet 3
[Block number

]

FX Configurator-EN-L
setting screen

Setting data

Data item

Setting value

Remark

TCP

Protocol

UDP
Active
Setting not required if
UDP is selected.

Unpassive

Open system

Fullpassive
Send

Fixed buffer

Receive
Procedure exist

Fixed buffer
communication
Connection
No.

No procedure
No pairs

Paring open

Pairs
No confirm

Existence confirmation

Confirm

Local station Port No.

Input format: Hexadecimal
Decimal

Destination IP address
input format

Hexadecimal

Destination
IP address
.

.

.

Destination Port No.

Adjust to input format

Input format: Hexadecimal

Ethernet open settings

TCP

Protocol

UDP
Active

Open system

Unpassive
Fullpassive
Send

Fixed buffer

Receive
Procedure exist

Fixed buffer
communication
Connection
No.

No procedure
No pairs

Paring open

Pairs
No confirm

Existence confirmation

Confirm

Local station Port No.

Input format: Hexadecimal
Decimal

Destination
IP address
.
Destination Port No.

App - 22

Destination IP address
input format

Hexadecimal

.

.

Adjust to input format

Input format: Hexadecimal

App - 22

APPENDIX

MELSEC-F

Recording sheet 4
[Block number
FX Configurator-EN-L
setting screen

]

Sub-net mask pattern
Setting the Ethernet
relay parameter

Default router IP address

Input format

App - 23

Setting data

Data item

Setting value

Remark

.

.

.

.

.

.

Decimal
Hexadecimal

Adjust to input format

Adjust to input format
Router information Input
format

App - 23

APPENDIX

MELSEC-F

Recording sheet 5
[Block number

]

FX Configurator-EN-L
setting screen

Setting data

Data item

General
settings

Setting value

Remark

Password

Mail address
SMTP
Server name
Decimal

IP address input format

Hexadecimal

IP address

Adjust to input format
.
SMTP
setting

.

.

SMTP
server port
number

Setting range: 1 to 65535
Initial value: 25

SMTP
authentication
method

Ethernet e-mail settings
Mail
Server
name

SMTP
login ID
SMTP
Password
POP
Server name
Decimal
POP setting

IP address input format

Hexadecimal

IP address

Adjust to input format
.
POP3
server port
number

Ethernet send mail
address settings

App - 24

No.1

Send mail address

No.2

Send mail address

No.3

Send mail address

No.4

Send mail address

No.5

Send mail address

No.6

Send mail address

No.7

Send mail address

No.8

Send mail address

No.9

Send mail address

No.10

Send mail address

.

.
Setting range: 1 to 65535
Initial value: 110

App - 24

APPENDIX

MELSEC-F

Appendix 8 Versioin Information
Ethernet Module version is shown as "VERSION" on the label attached to the right
side of the module as seen from the front.

Right side

Version

App - 25

App - 25

APPENDIX

MELSEC-F

MEMO

App - 26

App - 26

Warranty
Please confirm the following product warranty details before using this product.

1. Gratis Warranty Term and Gratis Warranty
Range
If any faults or defects (hereinafter "Failure") found to be
the responsibility of Mitsubishi occurs during use of the
product within the gratis warranty term, the product shall
be repaired at no cost via the sales representative or
Mitsubishi Service Company. However, if repairs are
required onsite at domestic or overseas location,
expenses to send an engineer will be solely at the
customer's discretion. Mitsubishi shall not be held
responsible for any re-commissioning, maintenance, or
testing on-site that involves replacement of the failed
module.

[Gratis Warranty Term]
The gratis warranty term of the product shall be for one
year after the date of purchase or delivery to a
designated place. Note that after manufacture and
shipment from Mitsubishi, the maximum distribution
period shall be six (6) months, and the longest gratis
warranty term after manufacturing shall be eighteen (18)
months. The gratis warranty term of repair parts shall not
exceed the gratis warranty term before repairs.

[Gratis Warranty Range]
1)

2)

The range shall be limited to normal use within the
usage state, usage methods and usage
environment, etc., which follow the conditions and
precautions, etc., given in the instruction manual,
user's manual and caution labels on the product.
Even within the gratis warranty term, repairs shall
be charged for in the following cases.
a) Failure occurring from inappropriate storage or
handling, carelessness or negligence by the
user. Failure caused by the user's hardware or
software design.
b) Failure caused by unapproved modifications,
etc., to the product by the user.
c) When the Mitsubishi product is assembled into
a user's device, Failure that could have been
avoided if functions or structures, judged as
necessary in the legal safety measures the
user's device is subject to or as necessary by
industry standards, had been provided.
d) Failure that could have been avoided if
consumable parts (battery, backlight, fuse, etc.)
designated in the instruction manual had been
correctly serviced or replaced.
e) Relay failure or output contact failure caused by
usage beyond the specified Life of contact
(cycles).
f) Failure caused by external irresistible forces
such as fires or abnormal voltages, and Failure
caused by force majeure such as earthquakes,
lightning, wind and water damage.
g) Failure caused by reasons unpredictable by
scientific technology standards at time of
shipment from Mitsubishi.
h) Anyother failure found not to be the
responsibility of Mitsubishi or that admitted not
to be so by the user.

2. Onerous repair term after discontinuation of
production
1)

Mitsubishi shall accept onerous product repairs for
seven (7) years after production of the product is
discontinued.
Discontinuation of production shall be notified with
Mitsubishi Technical Bulletins, etc.

2)

Product supply (including repair parts) is not
available after production is discontinued.

3. Overseas service
Overseas, repairs shall be accepted by Mitsubishi's local
overseas FA Center. Note that the repair conditions at
each FA Center may differ.

4. Exclusion of loss in opportunity and secondary
loss from warranty liability
Regardless of the gratis warranty term, Mitsubishi shall
not be liable for compensation of damages caused by
any cause found not to be the responsibility of
Mitsubishi, loss in opportunity, lost profits incurred to the
user or third person by Failures of Mitsubishi products,
special damages and secondary damages whether
foreseeable or not , compensation for accidents, and
compensation for damages to products other than
Mitsubishi products, replacement by the user,
maintenance of on-site equipment, start-up test run and
other tasks.

5. Changes in product specifications
The specifications given in the catalogs, manuals or
technical documents are subject to change without prior
notice.

6. Product application
1)

In using the Mitsubishi MELSEC programmable
logic controller, the usage conditions shall be that
the application will not lead to a major accident
even if any problem or fault should occur in the
programmable logic controller device, and that
backup and fail-safe functions are systematically
provided outside of the device for any problem or
fault.

2)

The Mitsubishi programmable logic controller has
been designed and manufactured for applications in
general industries, etc. Thus, applications in which
the public could be affected such as in nuclear
power plants and other power plants operated by
respective power companies, and applications in
which a special quality assurance system is
required, such as for Railway companies or Public
service purposes shall be excluded from the
programmable logic controller applications.
In addition, applications in which human life or
property that could be greatly affected, such as in
aircraft, medical applications, incineration and fuel
devices, manned transportation, equipment for
recreation and amusement, and safety devices,
shall also be excluded from the programmable logic
controller range of applications.
However, in certain cases, some applications may
be possible, providing the user consults their local
Mitsubishi representative outlining the special
requirements of the project, and providing that all
parties concerned agree to the special
circumstances, solely at the users discretion.

Revised History
Date

Revision

10/2009

A

Description
First Edition

FX3U-ENET-L
USER’S MANUAL

HEAD OFFICE: TOKYO BULDING, 2-7-3 MARUNOUCHI, CHYODA-KU, TOKYO 100-8310, JAPAN
HIMEJI WORKS: 840, CHIYODA CHO, HIMEJI, JAPAN

MODEL

FX3U-ENET-L-U-E

MODEL CODE

09R722

JY997D38001A
(MEE)

Effective Oct. 2009
Specifications are subject to change without notice.
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Author                          : MITSUBISHI ELECTRIC CORPORATION
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Title                           : FX3U-ENET-L USER'S MANUAL
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