Rockwell Automation 20-COMM-ER 20-COMM-ER Dual-Port EtherNet/IP Communication Adapter User Manual User Manual
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Rockwell Automation Publication 20COMM-UM015B-EN-P - July 2013
Glossary
IP Addresses
A unique IP address identifies each node on an EtherNet/IP network. An IP
address consists of 32 bits that are divided into four segments of one byte each. It
appears as four decimal integers separated by periods (xxx.xxx.xxx.xxx). Each
‘xxx’ can have a decimal value from 0 to 255. For example, an IP address could be
192.168.0.1.
An IP address has two parts: a network ID and a host ID. The class of network
determines the format of the address.
The number of devices on your EtherNet/IP network will vary depending on the
number of bytes that are used for the network address. In many cases you are
given a network with a Class C address, in which the first three bytes contain the
network address (subnet mask = 255.255.255.0). This leaves 8 bits or 256
addresses on your network. Because two addresses are reserved for special uses (0
is an address for the network usually used by the router, and 255 is an address for
broadcast messages to all network devices), you have 254 addresses to use on a
Class C address block.
To ensure that each device on the Internet has a unique address, contact your
network administrator or Internet Service Provider for unique fixed IP addresses.
You can then set the unique IP address for the adapter by using a BOOTP server
or by manually configuring parameters in the adapter. The adapter reads the
values of these parameters only at powerup.
L
Logic Command/Logic Status
The Logic Command is used to control the PowerFlex 7-Class drive (for example,
start, stop, and direction). It consists of one 16-bit word of output to the adapter
from the network. The definitions of the bits in this word depend on the drive,
and are shown in
The Logic Status is used to monitor the PowerFlex 7-Class drive (for example,
operating state and motor direction). It consists of one 16-bit word of input from
the adapter to the network. The definitions of the bits in this word depend on the
drive, and are shown in
.
0 1
7
15
23
31
Class A 0 Network ID
Host ID
0 1
7
15
23
31
Class B 1 0 Network ID
Host ID
0 1 2
7
15
23
31
Class C 1 1 0 Network ID
Host ID