Pepperl+Fuchs ICDM-RX/MOD User manual

MANUAL
ICDM-RX/MOD
Modbus Router User
FACTORY AUTOMATION

With regard to the supply of products, the current issue of the following document is applicable: The General Terms of
Delivery for Products and Services of the Electrical Industry, published by the Central Association of the Electrical Industry
(Zentralverband Elektrotechnik und Elektroindustrie (ZVEI) e.V.) in its most recent version as well as the supplementary
clause: "Expanded reservation of proprietorship".
ICDM-RX/MOD User Manual

ICDM-RX/MOD User Manual
Table of Contents
3
Table of Contents
1. Overview ......................................................................................................................... 5
1.1. Introduction ....................................................................................................................................... 5
1.2. Terms and Definitions ...................................................................................................................... 5
1.3. What is Modbus? .............................................................................................................................. 7
1.3.1. Modbus/RTU .............................................................................................................................. 7
1.3.2. Modbus/ASCII ............................................................................................................................ 7
1.3.3. Modbus/TCP .............................................................................................................................. 8
1.4. Modbus Router Functionality .......................................................................................................... 9
1.5. Multiple Gateway Modbus Networks ........................................................................................... 13
1.6. Modbus/RTU and Modbus/ASCII To-Slaves Interface................................................................. 16
1.6.1. Communication Methodology................................................................................................... 17
1.6.2. Local Public Modbus Slave Device Search Methodology......................................................... 18
1.7. Alias Device ID and Device ID Offset Functionality..................................................................... 18
1.7.1. Alias Modbus Device ID Functionality ...................................................................................... 20
1.7.2. Device ID Offset Functionality .................................................................................................. 20
1.8. Modus Master/Slaves Serial Port Mode (Private Serial Bus) ..................................................... 21
1.8.1. Master/Slaves Message Routing.............................................................................................. 22
1.8.1.1. Forward Broadcasts From Master Option....................................................................... 22
1.8.1.2. Private Device ID Range Setting .................................................................................... 23
1.9. Shared Memory Functionality........................................................................................................ 23
1.10. Remote Modbus Routing Capabilities ........................................................................................26
1.10.1. Serial Modbus Master(s) to Modbus/TCP Slave(s) ................................................................ 26
1.10.2. Modbus over Ethernet TCP/IP Master(s) to Modbus/TCP Slave(s) ........................................ 27
1.10.3. Modbus/TCP Master(s) to Modbus/TCP Slave(s) .................................................................. 28
1.10.4. Device ID Mapping to IP Address/Port/Slave Device IDs ....................................................... 29
2. Configuration Overview...............................................................................................33
2.1. Prerequisites ................................................................................................................................... 33
2.2. Configuration Overview.................................................................................................................. 33
2.3. Modbus Router Home .................................................................................................................... 34
3. Serial Menus.................................................................................................................35
3.1. Serial Port Overview Page ............................................................................................................. 35
3.2. Serial Port Configuration Page...................................................................................................... 35
4. Modbus Menus .............................................................................................................38
4.1. TCP/IP Configuration Pages .......................................................................................................... 38
4.1.1. Modbus over TCP Overview (not Modbus/TCP) Page ............................................................. 38
4.1.2. Modbus over TCP (not Modbus/TCP) Socket Configuration Page ........................................... 38
4.2. Modbus/TCP Configuration Page.................................................................................................. 39
4.3. Remote Modbus/TCP Device Configuration Page ....................................................................... 40
4.4. Modbus Alias Device ID Configuration Page ............................................................................... 41
4.5. Shared Memory Configuration Page............................................................................................. 41

2019-06
4
ICDM-RX/MOD User Manual
Table of Contents
5. Network Menu...............................................................................................................44
5.1. Network Configuration Page.......................................................................................................... 44
5.2. Password Page................................................................................................................................ 45
5.3. Security Page .................................................................................................................................. 45
5.4. Keys/Certs Page.............................................................................................................................. 46
6. Diagnostics Menu ........................................................................................................48
6.1. Serial Communication Statistics Page ......................................................................................... 48
6.2. Modbus RTU/ASCII over Ethernet TCP Statistics Page .............................................................. 49
6.3. Serial Interface Logs Page ............................................................................................................. 50
6.4. Known Modbus Slave Device List Page ....................................................................................... 50
6.5. Modbus/TCP and Serial Modbus Master Statistics Page ........................................................... 52
6.6. Modbus/TCP Connections Page.................................................................................................... 54
6.7. Modbus Alias Device ID Statistics Page....................................................................................... 55
6.8. Shared Memory Contents Page..................................................................................................... 55
6.9. Shared Memory Contents Page - Shared Coil Blocks................................................................. 56
6.10. System Log Page .......................................................................................................................... 57
7. System Menu ................................................................................................................58
7.1. Update Firmware Page ................................................................................................................... 58
7.2. Configuration File Page.................................................................................................................. 58
7.2.1. Saving a Configuration File....................................................................................................... 59
7.2.2. Loading a Configuration File..................................................................................................... 59
7.3. Device Snapshot Page ................................................................................................................... 59
7.4. Restore Defaults Page .................................................................................................................... 59
7.5. Reboot Page .................................................................................................................................... 59
8. Troubleshooting and Technical Support...................................................................60
8.1. Troubleshooting Checklist ............................................................................................................ 60
8.2. General Troubleshooting ............................................................................................................... 61
8.3. Daisy-Chaining ICDM-RX/MOD Units With Dual Ethernet Ports................................................. 61
8.4. Technical Support........................................................................................................................... 62

ICDM-RX/MOD User Manual
Overview
6/3/19
5
1. Overview
1.1. Introduction
This guide discusses ICDM--RX/MOD Industrial Gateway configuration for the ICDM--RX/MOD running the
Modbus Router application.
The Modbus Router application provides enhanced connectivity from a wide variety of Modbus masters to a
wide variety of Modbus slaves, advanced Master-to-Master connectivity, and connectivity from private Modbus
serial networks to public Modbus networks.
Supported Modbus masters include:
•Modbus/TCP
•Modbus/RTU serial
•Modbus/ASCII serial
•Modbus/ RTU
•Modbus/ASCII over Ethernet TCP/IP
Supported Modbus slaves include:
•Modbus/TCP
•Public and private Modbus/RTU serial
•Public and private Modbus/ASCII serial
Connectivity can be easily achieved between any master(s) and any public slave(s) anywhere on an Ethernet
network. Combined with a ICDM-RX/MOD running the Modbus/TCP application, both serial and Ethernet TCP/
IP Raw/ ASCII devices can be accessed anywhere on a network from any Modbus master.
Modbus Router was designed to greatly enhance system maintenance capabilities. Included are
comprehensive device and port specific diagnostic web pages that display status, message response timing,
time-outs, other error counts, and overall message statistics. A serial log is also included to provide message
level diagnosis for serial devices.
1.2. Terms and Definitions
This subsection defines terms and definitions used in this guide.
Te r m D e f i n i t i o n
Alias Device ID The device ID that the original received ID is changed to when an Alias Device ID is
configured.
Device ID
The Modbus device identification number. Device IDs include:
0= Broadcast
1-247 = Standard device IDs
248-255 = Reserved device IDs (generally used for vendor specific gateway functions)
Device ID Offset An offset applied at the slave serial port interface that changes the message device
ID range to match the serial device(s) device ID range.

6/3/19
6
ICDM-RX/MOD User Manual
Overview
Ethernet TCP/IP
A form of Ethernet connectivity that provides a level of guaranteed delivery and data
verification.This is used for many upper layer protocols such Modbus/TCP and can
be also used for transferring Modbus/RTU and Modbus/ASCII messages.
Local Slave Device A local slave device is one that is connected directly to a serial port on the gateway.
Master (or Client)
Mode
The method of operation when a PLC, a gateway, or an application is operating as a
Master or the message originator.
Modbus/ASCII An ASCII, or character based, form of Modbus.The base message is the same as
Modbus/RTU, but the format is somewhat different.
Modbus/RTU
The standard Modbus messages, in hexadecimal format, that are typically
transmitted over serial lines but can also be transmitted over other communication
methods such as wireless or Ethernet TCP/IP socket connections.
Note: Modbus/RTU over Ethernet TCP/IP is not the same as Modbus/TCP.
Modbus/TCP
An Ethernet based form of Modbus communication. The base message is the same
as Modbus/RTU, but a special Modbus header is included for packet identification
and routing purposes.
Polling
The process where a PLC or Application requests data on a continual basis. In this
operation the Master sends the request messages while the Slave responds to the
messages.
Public Slave
Device
A public slave device is one that can communicate to all master(s) on the Modbus
network.
Note: If a device is not specifically specified as a “public” or “private” slave device,
then it can be assumed to be a public device.
Private Slave
Device
A private slave device is one that can only communicate to a master that is connected
on the same serial bus, such as RS-485 or RS-422. Private slave device cannot
communicate to other masters on the Modbus network.
Received Device
ID The original device ID received in the Modbus message from a Modbus master.
Remote Slave
Device
A remote slave device is either a slave Modbus/TCP device or a serial slave device
attached to another gateway and accessed as a remote Modbus/TCP device.
Slave (or Server)
Mode
The method of operation when a PLC, a gateway, or an application is operating as a
Slave or the message receiver.
Sockets The method used to communicate between devices while communicating over
Ethernet TCP/IP.
Term Definition

ICDM-RX/MOD User Manual
Overview
6/3/19
7
1.3. What is Modbus?
This subsection discusses:
•Modbus/RTU
•Modbus/ASCII on Page 7
•Modbus/TCP on Page 8
1.3.1. Modbus/RTU
Modbus/RTU is native Modbus in hexadecimal format.These are the base Modbus messages that contain
simple read and write requests.The format is as follows:
Where:
•The terms Master or Client are used to identify the sender of the message.
•The terms Slave or Server are used to identify the devices responding to the message.
Modbus/RTU is used primarily for:
•Serial port connectivity
RS-485 is the most common serial mode, but RS-232 and RS-422 are also widely used. Commonly used
by both Master and Slave devices.
•Ethernet TCP/IP socket connections
This is not the same as Modbus/TCP on Page 8, but does provide a very simple method of interfacing to
remote devices. It is used by many applications and some OPC servers.
Note: This communication method typically is not supported by PLCs.
1.3.2. Modbus/ASCII
Modbus/ASCII is native Modbus in ASCII format. This protocol is used primarily by legacy devices and is no
longer supported as widely as Modbus/RTU.
Like Modbus/RTU, Modbus/ASCII contains the base Modbus messages that contain simple read and write
requests.The differences between Modbus/ASCII and Modbus/RTU are:
1. The message data is sent in ASCII format, so the message length is twice as long. It requires two ASCII
characters for each byte of data.
2. An 8-bit LRC is attached to verify the message instead of a 16-bit CRC.The LRC is also transmitted in
ASCII format.
3. There are defined starting and ending characters to determine a Modbus/ASCII messages.

6/3/19
8
ICDM-RX/MOD User Manual
Overview
The format is as follows:
Where:
•The terms Master or Client are used to identify the sender of the message.
•The terms Slave or Server are used to identify the devices responding to the message.
Modbus/ASCII is used primarily for:
•Serial port connectivity
RS-485 is the most common serial mode, but RS-232 and RS-422 are also used. Used primarily by legacy
Slave devices.
•Ethernet TCP/IP socket connections
This is not the same as Modbus/TCP, but does provide a very simple method of interfacing to remote
devices. It is used by some applications and some OPC servers.
Note: This communication method typically is not supported by PLCs.
1.3.3. Modbus/TCP
Modbus/TCP is an Ethernet network based protocol that contains a Modbus/RTU message, with the exception
of the 2-byte CRC. The Modbus/TCP message contains a header with information designed to provide
message identification and routing information. The format is as follows:
Where:
•The terms Master or Client are used to identify the sender of the message.
•The terms Slave or Server are used to identify the devices responding to the message.
•Modbus/TCP messages are typically sent to and received on a defined Ethernet TCP/IP socket of 502.
•Modbus/TCP implementations provide more capability, but also require more processing than simpler
Modbus/RTU implementations.
Modbus/TCP is used for connecting advanced Ethernet based devices, such as PLCs, HMIs, SCADA Systems,
and most OPC Servers to:
•Other Ethernet devices supporting Modbus/TCP.
•Remote serial Modbus/RTU and/or Modbus/ASCII devices through gateways (such as the ICDM-RX/MOD
running the Modbus Router or Modbus/TCP applications).
•Remote serial or Ethernet TCP/IP ASCII devices (barcode scanners, printers, RFID readers, visions
systems, etc) through a gateway (such as the ICDM-RX/MOD running the Modbus/TCP application).

ICDM-RX/MOD User Manual
Overview
6/3/19
9
1.4. Modbus Router Functionality
The Modbus Router application provides the following functionality:
•Provides robust connectivity from all supported master devices to all supported slave devices:
-Supported Masters:
-Modbus/TCP Master - accepts Modbus/TCP messages on up to eight TCP/IP ports. This includes
502 and seven configurable ports.
-Modbus/RTU Serial Master
-Modbus/ASCII Serial Master
-Modbus/RTU over Ethernet TCP/IP Master
-Modbus/ASCII over Ethernet TCP/IP Master
-Supported Slaves:
-Modbus/RTU Serial Slaves
-Modbus/RTU ASCII Slaves
-Remote Modbus/TCP Slaves (addressable to device ID and IP address/port)
-Remote Modbus/RTU Serial Slaves (via Modbus/TCP using another gateway)
-Remote Modbus/ASCII Serial Slaves (via Modbus/TCP using another gateway)
•Multiple ICDM-RX/MOD chassis can be used together to form a Modbus network.
•Supports up to 255 public Modbus devices per gateway and/or Modbus network. Both standard, (1-247),
and reserved, (248-255), device IDs are supported.
•All Modbus devices not configured remotely are assumed to be locally connected to the gateway.
•The locations of all local Modbus devices are determined automatically.
•Modbus Device ID Aliasing. Modbus message device ID can be aliased when messages are received from
a Modbus master.
•Device ID Offset. At the serial port interface, device IDs can have a positive or negative offset applied to
change the device ID range.
•Supports up to 96 Modbus/TCP connections. This can include any combination of slave and master
connections.
•Modbus/RTU and Modbus/ASCII over Ethernet TCP/IP Master specific:
-Can support up to six TCP/IP connections per serial port configuration.
-All messages received from any Ethernet TCP/IP Master connection enter the routing functionality and
can be routed to any local or remote device.
-Combined with a serial port redirector, such as the Pepperl+Fuchs Comtrol Secure Port Redirector, can
provide COM port functionality from a computer to the Modbus network.
•Supports connectivity to private Modbus serial buses, such as a serial master and slave(s) on a RS-485
loop:
-The Modbus master is provided connectivity to the public Modbus network.
-Only the master has direct access to the serial devices on the private serial network.
-Private slaves are protected from intrusion by other master(s).
-Both slave device specific and port level diagnostics are provided for private network communication.
•Advanced Master-to-Master connectivity is provided via the Shared Memory sub-system. Features are:
-Eight Holding Register blocks containing 200 registers each.
-Eight Coil blocks containing 160 coils each.
-Read access to all master(s) on the Modbus network.

6/3/19
10
ICDM-RX/MOD User Manual
Overview
-Block-specific configurable write-access control. For each block, writes can be enabled for all
master(s) or restricted to a specific serial, Modbus/TCP, or Ethernet TCP/IP master.
-Web pages provide configuration, diagnostics, display of block contents and shared memory clearing
capabilities.
•Modbus specific message handling:
-CRC verification of all messages received on the TCP/IP and serial Modbus/RTU interfaces.
-LRC verification of all messages received on the TCP/IP and serial Modbus/ASCII messages.
-Timing out of responses from slave Modbus devices.
-Transfer ID verification of all remote Modbus/TCP messages.
-Parameter checking of all slave responses.
-Broadcast message handling.
•System monitoring to ensure gateway operation:
-Gateway busy.
-Application message time-outs
-Message validity checking.
•Advanced diagnostics web pages:
-Modbus device specific statistics, response timing, and status. Up to 255 Modbus devices, both
attached and remote, can be monitored simultaneously.
-Modbus/TCP diagnostics, connection(s) status, error messages
-Serial port specific statistics and status.
-Serial port message logging.