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Rockwell Automation 25-COMM-E2P PowerFlex 25-COMM-E2P Dual-Port EtherNet/IP Adapter User Manual

Page 164

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164

Rockwell Automation Publication 520COM-UM003A-EN-E - June 2013

Glossary

I/O Data

I/O data, sometimes called “implicit messages” or “input/output,” is time-critical
data such as a Logic Command and Reference. The terms “input” (To Net) and
“output” (From Net) are defined from the controller’s point of view. Output is
produced by the controller and consumed by the adapter. Input is produced by
the adapter and consumed by the controller.

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 power-up.

Logic Command/Logic Status

The Logic Command is used to control the PowerFlex 520-series drive (for
example, start, stop, direction). It consists of one 32-bit word of output to the
adapter from the network. The definitions of the bits in this word are shown in

Appendix D

.

The Logic Status is used to monitor the PowerFlex 520-series drive (for example,
operating state, motor direction). It consists of one 32-bit word of input from the
adapter to the network. The definitions of the bits in this word are shown in

Appendix D

.

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