Addressing - Siemens SIMATIC ET 200SP System Manual

7.2.2

Addressing

Introduction
In order to address the automation components or I/O modules, they have to have unique
addresses. The following section explains the various address areas.
I/O address
I/O addresses (input/output addresses) are required in the user program to read inputs and
set outputs.
STEP 7 automatically assigns input and output addresses when you connect the modules.
Each module uses a continuous area in the input and/or output addresses corresponding to
its volume of input and output data.
Figure 7-5 Example with input / output addresses from STEP 7
STEP 7 assigns the address areas of the modules by default to the process image partition 0
("Automatic updating"). This process image partition is updated in the main cycle of the CPU.
Device address (e.g. Ethernet address)
Device addresses are addresses of programmable modules with interfaces to a subnet (e.g.,
IP address or PROFIBUS address). They are required to address the various devices on a
subnet, for example, to download a user program.
Distributed I/O system
System Manual, 09/2019, A5E03576849-AJ
Configuring
7.2 Configuring the CPU
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