Addressing Digital Modules - Siemens SIMATIC S7-1500/ET 200MP System Manual

Configuring
8.1 Configuring the CPU
Hardware identifier
STEP 7 automatically assigns a hardware identifier (HW identifier) for identification and
addressing of modules and submodules. The HW identifier is used, for example, for
diagnostics alarms or for instructions, to identify the faulty module or the addressed module.
The "System constants" tab contains all hardware identifiers and their symbolic names (of HW
identifier) for the selected module.
The HW identifiers and names of all modules of a device are also available in the default tag
table on the "System constants" tab.
Figure 8-6
8.1.2.2

Addressing digital modules

Introduction
The following section describes the addressing of the digital modules. In your user program,
you require the addresses of the channels of the digital module.
Digital module addresses
The address of a digital module's input or output is composed of the byte address and the bit
address. The channels of the digital module are assigned bit addresses.
Example: I 1.2
The example consists of:
I
1
2
When you insert a digital module into a free slot, STEP 7 assigns a default address. You can
change the proposed default address in STEP 7.
198
Example of a default tag table from STEP 7
Input -
Byte address The byte address depends on the module start address
Bit address You read the bit address from the module
Automation system
System Manual, 01/2023, A5E03461182-AK