Siemens Simatic S7-1500 CPU 1512C-1 PN User Manual page 167

Data record structure
The example in the figure below shows the structure of data record 0 for channel 0. The
structure is identical for channels 1 to 4. The values in byte 0 and byte 1 are fixed and must
not be changed.
You enable a parameter by setting the corresponding bit to "1".
Figure B-1
CPU 1512C-1 PN (6ES7512-1CK01-0AB0)
Manual, 12/2017, A5E40898741-AA
B.2 Structure of a data record for input channels of the analog on-board I/O
Structure of data record 0: Bytes 0 to 6
Parameter data records
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