Table of Contents
Advertisement
ICC
13.2 EtherNet/IP
13.2.1 Overview
The EtherNet/IP protocol is an application-level protocol implemented on top of
the Ethernet TCP/IP and UDP/IP layers. It shares its object model with
ControlNet and DeviceNet through the common Control and Information
Protocol (CIP). This protocol allows the transfer of data and I/O over Ethernet.
EtherNet/IP incorporates both the TCP and UDP layers of Ethernet in the
transmission of data. Because TCP/IP is a point-to-point topology, EtherNet/IP
uses this layer only for explicit messaging; i.e. those messages in which the
data field carries both protocol information and instructions for service
performance. With explicit messaging, nodes must interpret each message,
execute the requested task and generate responses. These types of messages
can be used to transmit configuration, control and monitor data.
The UDP/IP protocol layer, which has the ability to multi-cast, is used for
implicit (I/O) messaging. With I/O messaging, the data field contains only real-
time I/O data; no protocol information is sent because the meaning of the data
is pre-defined at the time the connection is established, which in turn minimizes
the processing time of the node during run-time. I/O messages are short and
have low overhead, which allows for the time-critical performance needed by
controllers.
The interface card supports both explicit and I/O messaging. Further, two
different types of I/O messaging are supported. One type (invoked when the
client opens a connection to the interface using assembly instances 20 & 70 or
21 & 71) is included with the implementation of the AC/DC drive profile, and
requires no user configuration. The other type, however, is entirely user-
configurable, and is invoked when the client opens a connection to the interface
using assembly instances 100 and 150.
The following sections demonstrate specific examples of how to use
EtherNet/IP to transfer data between the drive and Allen-Bradley Logix-brand
PLCs.
Some other notes of interest are:
•
The interface card supports the EtherNet/IP protocol (release 1.0),
administered by the Open DeviceNet Vendor Association (ODVA).
•
This product has been self-tested by ICC, Inc. and found to comply with
ODVA EtherNet/IP Conformance Test Software Version A-5.
•
I/O connection sizes for assembly instances 100 and 150 are adjustable
between 0 and 64 bytes (32 registers max @ 2 bytes per register = 64
bytes). Because registers are 16-bit elements, however, connection sizes
cannot be odd (i.e. 1, 3, 5 etc.)
•
The interface card's product type code is 2 (AC drive.)
64
Advertisement
Table of Contents
