User Manual

Rockwell Automation Publication 1756-UM005B-EN-P - January 2013 145
Glossary
Broadcast Data transmissions to all addresses.
Communication format Format that defines the type of information transferred between an I/O module
and its owner controller. This format also defines the tags created for each I/O
module.
Compatible match An electronic keying protection mode that requires the physical module and the
module configured in the software to match according to vendor, catalog number
and major . In this case, the minor of the module must be greater than or equal to
that of the configured slot.
Connection The communication mechanism from the controller to another module in the
control system.
ControlBus The backplane used by the 1756 chassis.
Coordinated System Time (CST) Timer value that is kept synchronized for all modules within a single ControlBus
chassis. The CST is a 64-bit number with μs resolution.
Direct connection An I/O connection where the controller establishes an individual connection
with I/O modules.
Disable keying Option that turns off all electronic keying to the module. Requires no attributes
of the physical module and the module configured in the software to match.
Download The process of transferring the contents of a project on the workstation into the
controller.
Electronic keying A system feature that makes sure that the physical module attributes are
consistent with what was configured in the software.
Exact match An electronic keying protection mode that requires the physical module and the
module configured in the software to match identically, according to vendor,
catalog number, major and minor .
Field side Interface between user field wiring and I/O module.
Inhibit A ControlLogix process that lets you to configure an I/O module but prevent it
from communicating with the owner controller. In this case, the controller does
not establish a connection.
Interface module (IFM) A prewired removable terminal block (RTB).
Listen-only connection An I/O connection that allows a controller to monitor I/O module data without
owning the module.
Major A module that is updated any time there is a functional change to the module
resulting in an interface change with software.