Mitsubishi QJ71C24N User Manual page 160

6 DATA COMMUNICATION USING THE NON PROCEDURE PROTOCOL
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The following is a program example of clearing the reception data by the
dedicated instruction "CSET."
(3) Receive data clear procedure using FROM/TO instruction
Write and read the receive data clear request (address: A8
procedure described below.
When resuming data communications with an external device, resume it after
completing the reception data clear processing with the Q Series C24.
Depending on the data communications system, it may be necessary to restart
data communications with the external device after notifying the external device
from the programmable controller CPU that resumption of communications is
possible.
(Clear Procedure)· ··When the CH1 side interface is used.
(1) While none of receiving, sending, and receive data clearing is being
performed, with the TO instruction, "1" is written to Receive data clear
request (address: A8
(2) Receive data clear processing is performed for the Q Series C24's OS area
(See Section 6.1.2).
(3) When receive data clear processing is completed, receive data clear request
(address: A8
H
The following page shows an example of a program to clear receive data with the
FROM/TO instruction.
Create a program that contains the contacts (user flags, etc.) indicating the
following statuses in the TO instruction.
• Contacts indicating that the reception data read request (X3/XA) and reception
abnormal detection (X4/XB) are OFF
• Contact indicating that no dedicated instruction (OUTPUT/PRR/INPUT) is
currently being executed
• Contact indicating that reception data clear processing is not currently being
performed
1 When the function version A Q Series C24 is used, resume data
communications a further 100 ms after the receive data clear request
(address: A8
).
H
) becomes "0."
/148 ) changes from a "1" to a "0."
H H
MELSEC-Q
Set the execution type
Set the request type
(Reception data clear)
Execute the reception
data clear
Normal completion
Abnormal completion
Reset the complete flag by
external command
/148 ) using the
H H
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