Siemens SIMATIC ET 200AL, System Manual

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Functions
5.3 Shared device
PROFINET with STEP 7
168
Function Manual, 05/2021, A5E03444486-AL
The module-internal shared output (MSO) function allows an output module to make its
output data available to up to four IO controllers. An IO controller has write access to the
channels of the output module. Up to three IO controllers can additionally have read-access
to the channels.
The following figure shows the MSO functionality.
① CPU 1516-3 PN/DP as IO controller
② CPU 1511-1 PN as IO controller
③ Output module with MSO
④ Write access to the output channels of the output module
⑤ Read access to the output channels of the output module
Figure 5-32 Example configuration with MSO
Advantages of MSI/MSO
Module-internal shared input/shared output (MSI/MSO) offers the following advantages:
•
Real-time acquisition in multiple CPUs
• Lower costs due to saving on additional IO devices and modules
• Lower space requirements due to saving on additional IO devices and modules
• Reduced communication load because no CPU-CPU communication is needed
• No additional programming effort is needed for CPU-CPU communication