Siemens SIMATIC ET 200AL, System Manual

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Functions
5.4 Interrupts
PROFIBUS with STEP 7 V13
Function Manual, 12/2014, A5E03775446-AC
77
FREEZE control command
After receiving the FREEZE control command from the DP master, the DP slaves of a group
freeze the current status of their inputs. The DP slaves send these frozen input data to the
DP master with the following cyclical frames.
The DP slaves freeze the current state of their inputs again after each new FREEZE control
command.
The state of the DP slave inputs is only send to the DP master cyclically again when the DP
master sends the UNFREEZE control command.
5.4 Interrupts
Interrupts and interrupt OBs for DPV1
Interrupts can be set by a DPV1 slave which ensure handling of the interrupt-triggering event
in the master CPU. The interrupt data is evaluated in the CPU and the diagnostics buffer and
the module state are updated even in the "STOP" operating mode. The OB is not processed
in STOP.
The following DPV1 interrupts are supported:
●
Status interrupt
● Update interrupt
● Vendor-specific interrupt
Detailed information is available in the descriptions on the OBs. You can use the
corresponding OBs that are provided by the operating system of the S7 CPUs for diagnostic
interrupts, hardware interrupts, and pull/plug interrupts.
OB 55 interrupt - Status interrupt
The status interrupt can be triggered when the operating mode of a device or module
changes, for example, from RUN to STOP.
OB 56 interrupt - Update interrupt
An update interrupt can be triggered if the parameters of a slot were changed. This may be
caused by local access or partner access to the parameters.
OB 57 interrupt - Vendor-specific interrupt
The event that triggers the vendor-specific interrupt can be specified by the manufacturer of
a DPV1 slave.