Siemens S7-1200 Manual page 23

4 Configuration/Engineering
Wrong decoding of the Connection Point or Instance IDs can occur.
NOTICE
As the byte ordering is "big endian" in the EDS file, the numbers may be
mistakenly ordered in "little endian" and therefore decoded wrong. This may end
up addressing the wrong connection points causing non-functional behavior of
the LCCF_EnetScanner block.
Make sure the byte ordering is adjusted.
As example the instance segment's value is 25 00 07 03, where
•
25 00 is the segment identifier for the instance segment.
•
07 03 is the value for the instance. Here the bytes must be swapped
otherwise the decimal representation of 07 03hex is 1795dec.
This would address a different instance instead of the correct instance 775.
NOTE The direction can also be derived from the EDS file as it is described there in the
correct order.
The O->T direction is listed before the T->O direction.
Do not assume, that the numbers in the Paramxxx or Assemxxx name always
indicate the Connection Point identifier. Here this is the case, however this is not
always like this, as these numbers are arbitrary numbers.
Now that the connection point identifier and the assembly identifier are known, they
can be transferred into the EnetIoSystem data block for the adapter as shown
below.
NOTE The AssemblyIDs or connection point identifiers are specific for each device
type. They may be different for different devices. This means ET200SP MF
always use, 775, 768 and 769 for their identifiers. A F6Nano motion controller
uses the identifiers 1, 100 (64hex) and 101 (65hex).
EtherNet/IP Scanner
Entry-ID: 109782314, V1.1.0, 04/2021
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