Mitsubishi MELSEC-A Series Reference Manual page 211

7. DATA LINK SETTINGS
(1)
(2)
M
R1
L2
m
1
L3/m
r2
3
R4
Checking the operation mode to be used
(a) Operation mode of the second tier: MELSECNET
This is because the slave stations (local stations and remote I/O stations) are
connected to either MELSECNET mode-compatible station or MELSECNET
mode-compatible station.
(b) Operation mode of the third tier: MELSECNET
This is because the slave stations (local stations and remote I/O stations) are
connected to either MELSECNET mode-compatible station or MELSECNET
mode-compatible station.
Checking the range assigned to the master station for the third tier with the link
parameters for the second tier
(a) According to the number of assignment point in Table 7.6, 384 points for link
relay (B) and 384 points for Link registers (W) are required for the first half link
parameters, and 256 points for link relay (B) and 256 points for link register (W)
are required for the second half link parameters.
(b) 34 points for M
area.
At least 66 points for the empty area of link register (W) is required for the
assignment of the M/R area for the third tier with the first half link parameters for
the second tier.
In the system configuration shown in Fig 7.44, since M/R area for the
second tier also has 132 points, this range can also be used for assignment.
Table 7.6 Number of assignment point for each station
First half link parameter
M L
B W
256 256
128 128
128 128
128 128
128 128
R area and 32 points for M
7 - 73
Second half link
M R M R B
256
34 32
128
128
128
34 32
34 32
composite mode
composite mode
R area are required for the M/R
parameter
W
256
128
128
128