Rockwell Automation 1788-CN2FFR EtherNet/IP and ControlNet to FOUNDATION Fieldbus Linking Device - Manual (Page 95)

Rockwell Automation Publication 1788-UM057B-EN-P - September 2014 93
Glossary
host Control system that has FOUNDATION fieldbus capabilities to configure and
operate FOUNDATION fieldbus segments. There are several classes of Host
systems:
• Class 61 - Integrated Host - Primary, or process Host that manages the
communication and application configuration of all devices on the
network.
• Class 62 - Visitor Host - Temporary, on process Host with limited access to
device parameterization.
• Class 63 - Bench Host - Primary, off process Host for configuration and
setup of a non-commissioned device.
• Class 64 - Bench host - Primary, off process Host with limited access to
device parameterization of an off-line, commissioned device.
• Class 71 - Safety Integrated Host - Primary, on-process Host that manages
the communication and application configuration of all safety and control
and monitoring devices on a network.
LAS See link active scheduler .
link A logical link is a connection between function blocks; a physical link is a
connection between fieldbus devices.
linking device As a bridge, enables peer-to-peer communication between H1 devices without
the need for host system intervention. As a gateway, connects the H1 network to
other plant control and information networks, such as EtherNet/IP and
ControlNet.
link active scheduler Abbreviated as LAS, this scheduler is responsible for coordinating all
communication on the fieldbus; maintaining a list of transmission times for all
data buffers in all devices that need to be cyclically transmitted. The LAS
circulates tokens, distributes time, probes for new devices, and removes
non-responsive devices from the link.
link master An LM is a device that contains LAS functionality that can control
communication on a FOUNDATION fieldbus H1 fieldbus link.
There must be at least one LM on the H1 link; one of those LM devices is
chosen as the LAS.
macrocycle A calculated time for a fieldbus device to send and receive data. The AOP can
automatically generate the value, or the value can be manually entered. The LAS
is responsible for scheduling of the segment macrocycle.
mode Control block operational condition, such as manual, automatic, or cascade.
network A network as applied in this document is the termination of one or more fieldbus
segments into an interface card of the Host system.
node The connection point at which media access is provided.
offline Perform tasks while the Host system is not communicating with the
field devices.