Siemens Simatic 6ES7 157-0AC80-0 A0 Series, Manual

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Diagnostics Using the User Program
10-6
DP/PA Link and Y Link Bus Couplings
A5E00193841-011
Device identifier
The device identifier is a code that uniquely identifies the DP slave (PROFIBUS ID
number).
Table 10-6 Structure of the device identifier
Byte 4 Byte 5 Designation
80
H
52
H
IM 157
10.2.2 Module diagnosis
The module diagnosis identifies the IM 157 slots for which there is a diagnosis.
The terms slave, module and slot
A slave is a bus node that can be accessed via a separate PROFIBUS address. It
can physically or logically consist of one or more modules. The slaves and their
modules are depicted in the module diagnosis in virtual slots:
A non-modular slave always occupies two slots.
The first slot represents a “virtual header module” and the second a “virtual
module”.
A modular slave that consists of x modules occupies x+1 slots.
The first slot is assigned to the header module; the remaining slots are
assigned in ascending order to the individual modules.
Example of a slot assignment
Underlying PROFIBUS
IM157 IM157
Coupler
Link
Slot
PROFIBUS address
1st slave
1 2
3
2nd slave
3 4
4
5 6
3rd slave
7 8
5
4th slave
9 10
7
11 12
Figure 10-2 Example of a slot assignment