Rockwell Automation 20-COMM-ER 20-COMM-ER Dual-Port EtherNet/IP Communication Adapter User Manual - Manual (Page 229)

Rockwell Automation Publication 20COMM-UM015B-EN-P - July 2013 229
Glossary
T
TCP (Transmission Control Protocol)
EtherNet/IP uses this protocol to transfer Explicit Messaging packets using IP.
TCP guarantees delivery of data through the use of retries.
U
UDP (User Datagram Protocol)
EtherNet/IP uses this protocol to transfer I/O packets using IP. UDP provides a
simple, but fast capability to send I/O messaging packets between devices. This
protocol verifies that adapters transmit the most recent data because it does not
use acknowledgements or retries.
UDDT (User-Defined Data Type)
A structure data type that you define during the development of an application
(for example, to convert 32-bit REAL parameter data for written and read values
to correctly display them in human readable format).
Update
The process of updating firmware in a device. The adapter and its connected
PowerFlex 7-Class host drive and its peripherals can be updated using various
Allen-Bradley software tools. See
Updating the Adapter Firmware on page 44 for
more information.
Z
Zero Data
When communication is disrupted (for example, a cable is disconnected), the
adapter and drive can respond with zero data. Zero data results in the drive
receiving zero as values for Logic Command, Reference, and Datalink data. If the
drive was running and using the Reference from the adapter, it will stay running
but at zero Reference.