B-40
FX Series PLC User's Manual - Data Communication Edition
N:N Network
7 Creating Programs
7.4 Cautions on Program Creation
7.4
Cautions on Program Creation
1. Effect on the operation cycle
When the N:N Network is used, the operation cycle in each PLC becomes longer by about 10% regardless of
the number of linked stations and adopted communication patterns.
2. Program for setting the N:N Network
1) Make sure to create a program for setting the N:N Network from step 0 using M8038 (drive contact).
Otherwise, the N:N Network is disabled.
2) Do not set M8038 to ON using a program or programming tool.
3) Set station numbers consecutively. If a station number that is used twice or more is skipped, link will not
be achieved normally.
4) Pay close attention when setting up the N:N Network for the master station in a program using Structured
Ladder, FBD or ST programming in the FX
1S
, FX
1N
, FX
1NC
, FX
2N
or FX
2NC
PLC.
For details, refer to Section 7.2.
3. Program for reading link devices
Do not change the contents of link devices at other stations.
1) When a link error (data transfer sequence error) occurs, the link device information is held in the status
just before occurrence of the link error.
Create a fail-safe program which does not cause abnormality even if a link error occurs.
4. Cautions on using FX
0N
/FX
1S
PLCs
1) Link pattern when FX
0N
/FX
1S
PLCs are used or included
When FX
0N
/FX
1S
PLCs are included in the system, make sure to set pattern 0 in D8178 (refresh range
setting).
If any other pattern is set, data transfer error occurs in all FX
0N
/FX
1S
PLCs included in the system, and
the link time becomes longer.
2) When user devices are occupied as system devices
In FX
0N
/FX
1S
PLCs, M503 to M511 and D201 to D255 are handled as devices dedicated to the N:N
Network, and cannot be handled as general devices any more. Do not set these devices to ON or OFF
using a user program, display unit or programming tool.
If these devices are set to ON or OFF, the N:N Network may malfunction.
5. Cautions on using FX
3G
/FX
3GC
/FX
3U
/FX
3UC
PLCs
1) Only ch 1 or ch 2 can be set in the N:N Network.
2) Do not use the N:N Network and parallel link at the same time.
(For example, it is not allowed to use ch1 for the N:N Network and use ch2 for parallel link.)
6. Link device update timing
Link device update in N:N network is executed in the interrupt processing.
Because the interrupt processing is generated asynchronously from operations of the sequence program, it
may be performed during ladder operation.
Summary of Contents for FX-485ADP
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Page 120: ...B 2 FX Series PLC User s Manual Data Communication Edition N N Network ...
Page 188: ...C 2 FX Series PLC User s Manual Data Communication Edition Parallel Link ...
Page 244: ...D 2 FX Series PLC User s Manual Data Communication Edition Computer Link ...
Page 344: ...E 2 FX Series PLC User s Manual Data Communication Edition Inverter Communication ...
Page 700: ...H 2 FX Series PLC User s Manual Data Communication Edition Programming Communication ...
Page 752: ...I 2 FX Series PLC User s Manual Data Communication Edition Remote Maintenance ...
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