Mitsubishi MELSEC QJ71C24, User Manual

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MELSEC-Q
6 DATA COMMUNICATION USING THE NON PROCEDURE PROTOCOL
(2) Setting values that can be changed
Of the initial settings from GX Configurator-SC stored in the buffer memory, only
the following setting values can be changed after data communication has
started.
• Received data count designation (addresses: A4
H
/144
H
)
• Receive complete code designation (addresses: A5
H
/145
H
)
(3) Timing and procedure for changing the setting values
1) Timing of change
To change the receive complete code and received data count after data
communication has started, change the setting when the status of the I/O
signals relating to the reading of receive data is as follows.
• Reception data read request (X3/XA) or reception abnormal detection
(X4/XB): ON
• Reception data read completion (X1/Y8): OFF
2) Change procedure
When data reception from an external device causes the reception data read
request (X3/XA)/reception abnormal detection (X4/XB) to turn ON, turn ON
the reception data read completion (Y1/Y8) after performing the following.
• Read the receive data.
• Change the setting values for the receive complete code and the received
data count.
(Example) When reading data received in the CH1 side interface
External
device side
Data 1 Data 2
Programmable
controller
CPU side
(X3)
Reception data read
completion
Received data count designation
(address: A4
H
)
Receive complete code designation
(address: A5
H
)
Setting value-A
1)
2)
3) 5)
4)
Reads
receive data
Data read request using
setting value -A/-1 Data read request using
setting value -B/-2
Reads
receive data
Setting value-1
Setting value-B
Setting value-2
(Y1)
Reception data read
request
(Program example: I/O signals for the Q series C24 are from X/Y00 to X/Y1F)
Reads the data that is equal to the receive
data count.
Change the setting value for the received
data count as needed.
Change the setting value for the receive
complete code as needed.
Reads receive data count.
Turns ON the reception data read
completion (Y1).
( 1)
1 When unit is in bytes
Read request
1)
2)
2)
3)
4)
5)