Interrupts, diagnostics, error, and system messages
5.3 Alarms
IM 155-6 PN ST interface module (6ES7155-6AU01-0BN0)
Equipment Manual, 10/2020, A5E03576904-AE
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5.2.2
Triggering a hardware interrupt
Triggering a hardware interrupt
If there is a process interrupt, the CPU interrupts user program execution and processes the
process interrupt block OB 40. The result that triggered the interrupt is added to the start
information of the hardware interrupt block.
Note
Diagnostics "Hardware interrupt lost" (from I/O module)
Avoid creating hardware interrupts cyclically.
If the hardware interrupt load is too high, hardware interrupts can get lost depending on the
number of I/O modules and the communication load.
5.2.3
Triggering a swapping interrupt
Triggering a swapping interrupt
If there is a swapping interrupt, the CPU interrupts user program execution and processes the
process interrupt block OB 83. The result that triggered the interrupt is added to the start
information of OB 83.
5.3
Alarms
5.3.1
Diagnostics alarms
Actions after a diagnostics alarm
There can be more than one diagnostic alarm at a given time. Each diagnostics alarm initiates
the following actions:
•
The ERROR LED of the interface module flashes.
•
Diagnostics are reported as diagnostic error interrupts to the CPU of the IO controller and
can be read via data records.
•
Incoming diagnostics alarms are saved to the diagnostics buffer of the I/O controller.
•
OB 82 is called. If OB 82 is not available, the I/O controller goes into STOP mode.
You can find more information in the STEP 7 online help.
