Mitsubishi Electric Melsec Q Series User Manual page 151

6
FUNCTIONS
(7) DB buffering operation
The job data whose trigger condition has been met is processed as shown below
depending on the status of communication or DB buffering settings.
Communication
Transmission
impossible
Transmission
possible
Table 6.4 DB buffering operation
Data of
status DB buffer
Stored/ Invalid
Not stored Valid
Invalid
Stored
Valid
Not stored Valid/Invalid
Check the DB buffer status (No. of bufferings, utilization) and prevent the full
status of the DB buffer.
• Section 7.10.4 Setting items in DB Buffering
• Section 7.13.6 Operating the DB buffering
Processing content
1 When the job data cannot be sent to the database, one of the following
processing is performed after the detection of a timeout.
• DB buffering function is invalid : Job execution is cancelled.
• DB buffering function is valid : Job data is stored to DB buffer.
2 The content of DB buffer is resent after recovery.
• Automatically resend buffer : After recovery, the data is resent automatically.
• Manually resend buffer : After recovery, the data is resent when the resend
operation is performed.
Communication recovery
Job startup
After sending,
timeout detected
Stored to DB buffer
Figure 6.12 Processing content of DB buffering
The job processing which is started up while the data is being stored differs
depending on the settings of DB buffering.
(8) Operation while data is being stored to DB buffer in this section
DB buffering setting
Immediate sending
Adding to the buffered data Job data is stored to DB buffer.
Manual resend
Auto resend
operation
Resend Automatically Resend Manually
resend buffer data resend buffer data
6.1 DB Interface Function
6.1.10 DB buffering function
Operation
Job execution is cancelled.
Job data is stored to DB buffer.
Data is sent to database.
Data is sent to database.
Data is sent to database.
Job startup
Send
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