Chained Multicast Messaging - ABB ACSM1 Firmware Manual

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Follower-to-follower(s) broadcasting
Token
Master Follower Follower Follower
Dataset table Dataset table Dataset table Dataset table
Target Grp = 255
(LocalDsNr)
(RemoteDsNr) (RemoteDsNr)

Chained multicast messaging

Chained multicasting is supported only for drive-to-drive reference 1 by the firmware.
The message chain is always started by the master. The target group is defined by
parameter 57.13 NEXT REF1 MC GRP. The message is received by all followers
that have parameter 57.12 REF1 MC GROUP set to the same value as parameter
57.13 NEXT REF1 MC GRP in the master.
If a follower has parameters 57.03 NODE ADDRESS and 57.12 REF1 MC GROUP
set to the same value, it becomes a submaster. Immediately after a submaster
receives the multicast message, it sends its own message to the next multicast
group defined by parameter 57.13 NEXT REF1 MC GRP.
The duration of the entire message chain is approximately 15 microseconds
multiplied by the number of links in the chain (defined by parameter 57.14 NR REF1
MC GRPS in the master).
Appendix B – Drive-to-drive link