Addressing Digital Modules - Siemens SIMATIC S7-1500 Automation System System Manual

7.1.2

Addressing digital modules

Introduction
The addressing of digital modules is described below. 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.
If you enable the value status for a digital module, then additional bytes are allocated in the
input address area. Each bit is assigned to a channel and returns information about the
validity of the digital value (0 = incorrect value).
The value status is a binary additional information of a digital input signal. The value status is
entered simultaneously with the process signal in the process image input and provides
information about the validity of the signal.
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.
S7-1500 Automation System
System Manual, 01/2013, A5E03461182-01
Input -
Byte address The byte address depends on the module start address
Bit address You read the bit address from the module
Configuring
7.1 Address assignment
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