Mitsubishi MELSEC-A Series Reference Manual page 214

7. DATA LINK SETTINGS
(4) Assignment of link registers (W)
(a) An empty area in the W0 to 5F range is used to assign an M/R area for the third
Fig 7.46 Link registers (W) assignment example
tier with the link parameters for the second tier.
The assignment can also be made by using the M/R area for the second tier
W360 to 3E3.
7 - 76
Master station (M)
station No. 1(R1)
*1 *2 *3 *4
Remote I/O
*5