5 - 3 5 - 3
MELSEC-Q
5 DATA COMMUNICATION USING THE MELSEC COMMUNICATION
PROTOCOL
(2) System settings using the GX Configurator-SC
When it is necessary to change the default values registered in the Q series C24,
perform the settings as indicated in Chapter 8 and register these to the flash
ROM in the Q series C24.
โข MC protocol system setting
โข Transmission control and others system setting
POINT
To write from the external device to the intelligent function module installed in the
MELSECNET/H remote I/O station during communication using the MC protocol,
set the "Write allow/prohibit during PLC CPU RUN" in the GX Developer to enable.
5.1.4 Support of multiple CPU system or redundant system
When the external device accesses a QCPU in a multiple CPU system or redundant
system, it is possible to selectively access either a control or non-control CPU in the
multiple CPU system or a control or standby system CPU or System A or System B
CPU in the redundant system by specifying the target QCPU in "Requested module
I/O No." of the QnA compatible 4C frame for the MC protocol.
Refer to the Reference Manual for details.
Refer to Chapter 2 of this manual for the system configuration.
(Example) When multiple CPU No.1 is specified
Frame ID No.
46
H
05
H
Self-station No.
Command
Sub command
Device code
Head device
Number of device
points
Sum check code
38
H
30
H
33
H
30
H
33
H
45
H
30
H
30
H
30
H
30
H
30
H
30
H
34
H
30
H
31
H
30
H
30
H
30
H
31
H
58
H
2A
H
30
H
30
H
30
H
30
H
34
H
30
H
30
H
30
H
30
H
35
H
H
F
L
8
H
0
L
7
H
0
L
0
H
0
L
0
H
0
L
0
H
0
L
1
H
0
L
1
X
L
0
L
5
PC No.
โ
0
โ
0
H
0
โ
0
โ
4
H
0
โ
0
โ
0
โ
4
โ
3
โ
0
โ
0
โ
0
E
N
Q
Station No.
30
H
35
H
H
0
L
5
Network No.
30
H
37
H
H
0
L
7
โ
E
33
H
36
H
H
3
L
6
Requested module
station No.
Requested module
I/O No.
(Command massage of the QnA compatible 4C frame format 1)
REMARK
โข When using the Q series C24 in a multiple CPU system, it is necessary to specify
the QCPU that controls the Q series C24 (hereinafter referred to as the control
PLC) using GX Developer.
โข It is also possible to mount a Q series C24 of function version A in a multiple CPU
system. In this case, it is only possible to access the control PLC (PLC No.1).
โข It is only possible to access the control PLC if data is communicated by means of
frames other than the QnA compatible 4C frame.