Mitsubishi MELSEC-A Series Reference Manual page 200

7. DATA LINK SETTINGS
(2)
Link with inputs (X) and outputs (Y) in only the
third tier
(3)
Third tier operation
mode
MELSECNET mode
MELSECNET mode
MELSECNET
composite mode
The input (X) and output (Y) range that can be assigned to the master station for the
third tier can use the area starting from the I/O use range of host station. This is the
same range as assignment range of the master station for the second tier.
If inputs (X) and outputs (Y) are used to establish data link between the master
station for the third tier and the master station for the second tier, the assignment
range of the master station for the third tier should exclude this range.
Fig 7.31 Assignment of inputs (X) and outputs (Y) (When A3NCPU is used)
Table 7.4 lists the nine types of combinations ((1) to (9)) depending on the operation
modes set for the second tier and the third tier.
Table 7.4 Operation mode combinations for second/third tier
MELSECNET mode
1)
2)
3)
Link with inputs (X) and outputs (Y) in the second and
third tiers
Second tier operation mode
MELSECNET mode
4)
5)
6)
7 - 62
MELSECNET
composite mode
7)
8)
9)