<Appendix 4. Link Master Functions>
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IM 01E21A02-03EN
A4.3 Transition of LM Function
There are the following procedures for an LM device to become the LAS:
(1) If the LM device judges that there is no LAS on the link, in such a case as when the link
starts up or when the LAS fails*, the LM declares itself as the LAS, and then becomes the
LAS.* Backup for LAS (Figure A4.2)
(2) The LM device requests the LAS on the link to transfer the right of being the LAS, and then
becomes the LAS.
In either case, if there are multiple LM devices on the link, the LM device which has the smallest
V(ST) x V(TN) value becomes the LAS.
LM
Node address:
0x15
SlotTime = 5
LM
Node address:
0x16
SlotTime = 5
Node address: 0x14
SlotTime = 5
Basic device
Node address:
0xF1
Basic device
Node address:
0xF2
Basic device
Node address:
0xF3
Basic device
Node address:
0xF4
LAS
LAS
In the event that the current LAS in
this segment (node address 0x14)
fails, the LM with the address of 0x15
takes its place to become the LAS.
LM
FA0402.EPS
Figure A4.2 Backup of LM Function