User`s guide

44 Chapter 4 IA Profiles and Procedures
the attached device, which can be Modbus ASCII, Modbus RTU, DF1 Full-
Duplex, DF1 Half-Duplex, Omron Hostlink, Omron FINS, and Omron
CompoWay/F. It can also be a serial port protocol that meets Digi’s
definition of a “user defined” protocol, that is, one that has fixed header and
trailer strings that bound all message packets and where each protocol
request is followed by a single response.
For the network connection, Digi recommends TCP sockets, which works
regardless of the serial port protocol specified and provides an efficient and
reliable network service. Another option is UDP sockets, which also works
with all the serial port protocols, although it lacks TCP socket reliability. For
Modbus devices, Modbus/TCP is an option, and for DF1 Full-Duplex
devices, Allen Bradley Ethernet and Ethernet/IP are options.
Locating Setup Information: Slave Side
See "Configuring a Serial-Connected Slave: Generic Procedure" on page
49.
Locating Setup Information: Master Side
• To configure TCP socket or UDP socket communication, see
"Configuring a Serial-Connected Master: TCP/UDP Sockets" on
page 50.
• To configure any of the other network communication protocols, see
"Configuring a Serial-Connected Master: Generic Procedure" on
page 50.
Modbus Profile: Serial-Connected Slave
About This Profile
Use this profile to connect a slave device (or devices) using Modbus RTU
or Modbus ASCII. This profile is applicable to environments in which
multiple masters will control the slave or slaves.
Configuration Options
The serial port connection must be configured for the protocol required by
the slave, in this case Modbus RTU or Modbus ASCII.
The network connection usually does not require configuration. The only
exception is if the master requires COM port redirection. In this case, the
master is an application that resides on a PC, such as a Microsoft Windows