Mitsubishi MELSEC-A Series Reference Manual page 184

7. DATA LINK SETTINGS
(5) Assignment of inputs (X) and outputs (Y)
In this system example, inputs (X) and outputs (Y) are not to be used because there
is an empty area in the link relay (B) assignment. However, to simplify the
explanation, 128 input (X) points and 128 output (Y) points each are assigned to local
stations No.1 and No.3.
(Inputs (X) and outputs (Y) are not set for local station No.2.)
(a) Range used for data link by master station
The master station uses the X/Y0 to 14F range as I/O of host station.
For data link, the X/Y150 to 7FF range can be used.
(b) Input and output range used for data link by local station No.1
The local station No.1 uses the X/Y0 to 7F range as I/O of host station.
For the data link, the X/Y80 to 1FF range can be used.
(c) Input and output range used for data link by local station No.3
The local station No.3 uses the X/Y0 to FF range as I/O of host station.
For the data link, the X/Y100 to 7FF range can be used.
Fig 7.23 Input (X) and output (Y) assignment example
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