Mitsubishi MELSEC-A Series Reference Manual page 164

7. DATA LINK SETTINGS
(1) Assignment of link relay (B)
(a) Fig 7.9 shows the case when assigning 256 points to the master station, 128
points to local station No.1, 128 points to local station No.2, and 128 points
empty area between local station No.1 and local station No.2.
Fig 7.9 Link relay (B) assignment example
(b) The empty area marked with *1 in the M/L area in Fig 7.9 cannot be used as a
substitute for internal relay (M) in the master station and all local stations.
The M/L area is the range (B0 to 27F) from the minimum device number to the
maximum device number assigned by the link parameters.
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