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AS-i Gateway with Profinet device interface
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Step7 programmer's notes
41706
Diagnostics alarm procedure:
1. As soon as a device has detected a diagnostics alarm, the alarm is automatically forwarded to the
fieldbus controller.
2. When a diagnostics alarm arrives in the fieldbus controller, an interrupt of the cyclic program
(OB1) processing is automatically generated.
3. In this case the Simatic operating system calls the OB82 (diagnostics alarm OB) which allows
specific alarm processing.
The incoming and outgoing diagnostics alarms are signalled via OB82.
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Create OB82 (can be empty).
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If OB82 does not exist, the S7 goes into the STOP state at each alarm.
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The LED [SF] on the S7 starts to light at the first incoming alarm and goes out with the last outgoing alarm.