Siemens SIMATIC S7-1500 Automation System System Manual page 86

Configuring
7.1 Address assignment
Example for the assignment of channel addresses (digital module)
The following figure shows how the addresses of the individual channels of the digital input
module (e.g., 6ES7521-1BL00-0AB0) are determined.
Figure 7-8
Note
You can also assign symbolic names to the addresses in STEP 7's PLC tag table.
Reference
Additional information on addressing and address allocation with value status can be found
in the manuals of the digital modules, and in the online help for STEP 7.
86
Example for the assignment of channel addresses (digital module)
S7-1500 Automation System
System Manual, 01/2013, A5E03461182-01