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MELSEC-F
COMMUNICATION PROCEDURE5
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(2) Subnet mask pattern (BFM#512, 513)
(a) Set the subnet mask.
*1
(Setting range: C0000000 to FFFFFFFCH)
Consult the network administrator for the setting.
(b) When not using the subnet mask, set any of the following table values
according to the class.
*1 Ethernet networks include small-scaled network systems where multiple
devices are connected to one Ethernet hub along with medium and large-
scaled network systems where multiple small-scaled networks are
connected by routers, etc.
The subnet mask logically divides one network, where many devices are
connected, into multiple sub-networks to facilitate administration.
(3) Router IP address (BFM#514, 515)
Set the IP address of the router to be used when FX3U-ENET-L communicates
with the target device on another Ethernet network (refer to (4) below).
Set the value that satisfies the following conditions.
• Condition 1: The IP address class is either A, B or C.
• Condition 2: The sub-net address of the default router is the same as that of
the local station Ethernet module.
• Condition 3: The host address bits are not all "0" or all "1".
Class Mask value
Class A FF000000
H
Class B FFFF0000H
Class C FFFFFF00H
POINT
(1) All devices on the same sub-network must have a common subnet mask.
(2) When not administrated by the sub-network, the connected devices need not
have a subnet mask. (Set the network address of the corresponding class.)
10000001
81
H
00000101
05
H
00101111
2F
H
00000001
01
H
FF
H
00
H
FF
H
FC
H
11111111 0000000011111111111111 00
00000001100000010000010100101111
(Example) Class B
81
H
05
H
2F
H
01
H
IP address
Subnet mask
IP address
Network address
Subnet address Host address