Siemens Simatic ET 200MP Manual page 47

Structure of a data record in the DI mode
The example in the following figure shows the structure of data record 0 for channel 0. The
structure of channels 1 to 31 is identical. The values in byte 0 and byte 1 are fixed and may
not be changed.
Enable a parameter by setting the corresponding bit to "1".
Figure B-1
DI 32x24VDC HF digital input module (6ES7521-1BL00-0AB0)
Manual, 09/2016, A5E03485935-AF
Structure of data record 0: Bytes 0 to 3
B.2 Structure of the parameter data records DI mode
Parameter data records
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