D-82
FX Series PLC User's Manual - Data Communication Edition
Computer Link
7 Commands
7.13 On-demand Function
7.13.3 On-demand function specification method and specification examples
This subsection explains the on-demand function specification method and specification examples.
When using ch2 in an FX
3G
, FX
3GC
, FX
3U
or FX
3UC
Series PLC, exchange special auxiliary relays (M) and
special data registers (D) according to the table below.
*1.
FX
0N
, FX
1S
, FX
1N
and FX
1NC
PLCs do not support this device.
1. Specification method
The specification method in the control procedure format 1 is shown below:
1) Specify the data quantity specification range while satisfying the following condition:
- Amount of data
40H (= 64 in decimal)
2) The PLC adds "FE" as the PLC number.
3) Express the station number, PLC number, number of device points and sum check code in hexadecimal.
IMPORTANT
Do not use the on-demand function when the system configuration is not 1-to-1 type.
If the on-demand function is used in the multi-drop link system in which the computer and PLC CPUs have
the 1-to-N configuration, the transfer data and on-demand send data in the control procedure format 1 or 4
are destroyed, and normal data sending is not possible.
All PLCs except FX
3G
, FX
3GC
, FX
3U
and FX
3UC
PLCs
FX
3G
, FX
3GC
,
FX
3U
and FX
3UC
PLCs (ch1)
FX
3G
, FX
3GC
, FX
3U
and FX
3UC
PLCs (ch2)
M8127
*1
M8427
M8128
M8428
M8129
M8429
D8127
D8427
D8128
D8428
PLC
On-demand send processing
M8127
Writes data to be sent and
amount of data to be sent.
ON
S
T
X
Data to be
sent
Added by PLC
E
T
X
OFF
Write the head device number (data register)
storing the data to be sent to the special data
register D8127.
Write the amount of data to the special data
register D8218.
Computer side
PLC side
P
LC No.
Sta
tio
n
No.
S
um check
code
Summary of Contents for FX-485ADP
Page 2: ......
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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