Interrupts; Evaluating Interrupts; Trigger A Diagnostics Interrupt; Triggering A Hardware Interrupt - Siemens SIMATIC ET 200AL Equipment Manual

5.2

Interrupts

5.2.1

Evaluating interrupts

Introduction
With certain process statuses/errors, the DP slave in each case creates an interrupt block with
the corresponding information in the diagnostics frame (DPV1 interrupt mechanism).
Regardless of this, the diagnostic status of the DP slave is displayed in the identifier-related
diagnostics, in the module status, and in the channel diagnostics.
Interrupts in DPV1 mode
The ET 200AL distributed I/O system supports the following interrupts:
• Diagnostics interrupts
• Hardware interrupts
• Pull/plug module interrupt
5.2.2

Trigger a diagnostics interrupt

For an incoming or outgoing event (for example, wire break on a channel of an I/O module),
the interface module triggers a diagnostics interrupt if the I/O modules were configured
accordingly and "Enable:diagnostics interrupt" is set.
The CPU interrupts user program execution and processes the diagnostics interrupt OB
(OB 82). The event that triggered the interrupt is entered in the start information of the
diagnostics interrupt OB.
5.2.3

Triggering a hardware interrupt

When a hardware interrupt occurs, the CPU interrupts execution of the user program and
processes the hardware interrupt OB, for example OB 40. The event that triggered the
interrupt is entered in the start information of the hardware interrupt OB.
Note
Diagnostics "Hardware interrupt lost" (from I/O module)
Do not use hardware interrupts for technological purposes (e.g., cyclical generation of
hardware interrupts).
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.
IM 157-1 DP (6ES7157-1AA00-0AB0)
Equipment Manual, 08/2021, A5E32100641-AE
Interrupts, error messages, diagnostics and system alarms
5.2 Interrupts
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