Global Function (Gw Command); Control Specification And Example Of Global Function - Mitsubishi Electric MELSEC FX Series User Manual

FX communication
8.9

Global Function (GW command)

This function is to turn on and off the global operation flag at all stations in the multidrop link.
For an FX series programmable controller this is special auxiliary M8126, and for an A series
programmable controller, it is Xn2 of the computer link unit.
This function can be used for initialization, resetting or simultaneous star t/stop of all
programmable controller stations.
8.9.1

Control Specification and Example of Global Function

The global function is to turn on or off the special auxiliary relay M8126 (global operation flag) at
all stations in the multidrop link.
• The station number specified in the control protocol must indicate all stations, and is hence
specified as FFH ("FF"). If other than FFH is specified as the station number, the special
auxiliary relay M8126 of the specified station is turned on/off.
• No reply is given by the programmable controller to this command.
• If the programmable controller power is turned off, the communication format changed, or the
programmable controller is stopped, the special auxiliary relay M8126 of that station is turned
off, and the global function operation is cleared.
1 ) Control specification
Protocol format 1 is shown.
Global function command
Computer
Programmable
controller
Notes
• The station number, PC (PLC) number, number of devices, and sum check code are
expressed in hexadecimal.
2 ) Specification example
To turn on the global operation flag at all programmable controller stations in the computer link;
auxiliary relay M8126 in an FX series PLC station, and Xn2 in an A series programmable
controller station.
Character area A
The sum check is
calculated over
this range
E
N F F
Q
Computer
46H 46H 46H
05H
Prpgrammable
controller
Indicates that the global operation flag is turned ON.
"FF" is specified to indicate all stations.
For a specific station, specify the station number between "00" to "0F"
("00" to "1F" for A series).
Control flag
(1 characters)
When data value is "1" (31H), global operation flag is tumed on.
When data value is "0" (30H), global operation flag is tumed off.
F F G W 0 1 1 7
46H 47H 57H 30H 31H 31H 37H
Commands 8
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