Emerson Rosemount 2230, Reference Manual

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Reference Manual
00809-0100-2230, Rev CA
Configuration and Operation
July 2017
Configuration and Operation
4.9 Device capabilities
4.9.1 Link Active Scheduler
The Rosemount 2230 can be designated to act as the backup Link Active Scheduler (LAS) in the event
that the LAS is disconnected from the segment. As the backup LAS, the Rosemount 2230 will take over
the management of communications until the host is restored.
The host system may provide a configuration tool specifically designed to designate a particular device
as a backup LAS. Otherwise, this can be configured manually.
4.9.2 Device addressing
Foundation fieldbus devices use addresses divided into four sub ranges as shown in Table 4-3 .
Table 4-3. Address Ranges for F
OUNDATION
fieldbus devices
The Link Active Scheduler device (LAS device) probes a list of addresses to allow devices to come online
during normal operation. The LAS can "skip" probing certain addresses in the range to speed up how long
it takes to detect new devices on the bus.
4.9.3 Capabilities
Virtual Communication Relationship (VCRs)
Table 4-4. VCR’s
Address range
(decimal) Address range
(hexadecimal)
Allocation
0 through 15 00 through 0F Reserved.
16 through 247 10 through F7
Permanent devices.
Address range 16 - 247 is subdivided into addresses
that are LAS capable (lower end) and not LAS capable
(upper end).
248 through 251 F8 through FB New or decommissioned devices
252 through 255 FC through FF
Temporary (“visitor”) devices. Example: 375/475
Field Communicator.
Item Number of VCR’s
Maximum number of VCR’s 38
Number of client and server VCR’s 20
Number of publisher VCR’s 20
Number of subscribers VCR’s 32
Number of source VCR’s 2
Number of sink VCR’s 0