Rockwell Automation 1203-EN1 EtherNet/IP-to-SCANport Module - Manual (Page 173)

Glossary G-5
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 module by
using a BOOTP server or by manually configuring parameters in the
module. The module reads the values of these parameters only at
power-up.
L
Logic Command/Logic Status
The Logic Command is used to control the drive (e.g., start, stop,
direction). It consists of one 16-bit word of input to the module from the
network. The definitions of the bits in this word depend on the drive.
The Logic Status is used to monitor the drive (for example, operating
state, motor direction). It consists of one 16-bit word of output from the
module to the network. The definitions of the bits in this word depend on
the drive.
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