Siemens SIMATIC C7-613, Manual

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Operating the C7-613
5-28
C7-613 Control System
A5E00138934-03
5.6.7 Number of Messages in the Event Buffer (Quantity)
Overview
You determine the number of messages in the event buffer as follows:
• By selecting the special screen “Messages > Quantity”
• By means of the user program by calling the “HMI API” FB
This ensures that you can carry out a backup in case of an imminent overflow of
the event buffer.
Selecting the Special Screen “Messages > Quantity”
Select the special screen Messages > Quantity . This provides you with an
overview of the following:
•
The number of messages that are still pending
• The total number of messages in the buffer.
Calling the “HMI API”FB
If a message is indicated on the display (OBJ_TYPE parameter on the “HMI API”
FB has the value “2”), the “ADDINFO” parameter on “HMI API” FB indicates the
current number of messages in the event buffer. This ensures that you can carry
out a backup in case of an imminent overflow of the event buffer.
Since the operational messages are not output directly to the display, the filling
level of the event buffer cannot be shown either. Proceed as follows in order to
see the filling level of the message buffer nevertheless:
1. Trigger a fault message specially created to this purpose at specific intervals.
2. Call up the “HMI API” FB.
3. Wait until the fault message is displayed (“HMI API” FB, parameter
OBJ_TYPE = 2).
4. Read out the filling level from the “ADDINFO” of the called “HMI API” FB.
5. Acknowledge the fault message.