Rockwell Automation Publication 750COM-UM009A-EN-P - May 2017 187
Glossary
devices. This protocol verifies that adapters transmit the most recent data
because it does not use acknowledgments or retries.
UDDT (user-defined data type) A structure data type that defines the development of an application, (for
example, to convert 32-bit REAL parameter data for write and read values then
display them in human readable format).
Update The process of updating firmware in a device. The device can be updated using
various Allen-Bradley software tools. See Updating the Interface Firmware on
page 47 for more information.
Zero Data When communication is disrupted (for example, a cable is disconnected), the
interface 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 by using the reference from the interface, it stays
running but at zero reference.