Modbus/Tcp - Communication Protocol; Contents Of This Chapter; Modbus/Tcp - ABB FENA-01 User Manual

Modbus/TCP – Communication protocol 99
8
Modbus/TCP –
Communication protocol

Contents of this chapter

This chapter describes the Modbus/TCP communication protocol
for the adapter module.

Modbus/TCP

Modbus/TCP is a variant of the Modbus family of simple, vendor
neutral communication protocols intended for supervision and
control of automation equipment. Specifically, it covers the use of
Modbus messaging over TCP connection on an IP network.
The FENA adapter module acts as a Modbus/TCP server with
support for the ABB Drives and Transparent profiles. The adapter
module also supports Modbus over UDP. The only difference
between Modbus/TCP and Modbus/UDP is that in Modbus/UDP
the transport layer protocol is UDP instead of TCP.
The supported Modbus commands are listed in section Function
codes on page 100. Two simultaneous Modbus/TCP connections
are supported, that is, two clients can be connected to the adapter
module at a time.
For information of the port used with Modbus/TCP or Modbus/UDP,
see TCP and UDP service ports on page 417.