Direct Data Exchange; Introduction - Siemens SIMATIC ET 200AL System Manual

5.8

Direct data exchange

5.8.1

Introduction

This section describes the direct data exchange function.
Principle of operation
Starting with firmware version V2.8, the S7-1500 CPU supports direct data exchange (cross
data traffic) with other S7-1500 CPUs.
In the case of direct data exchange, an S7-1500 CPU provides cyclic user data from the
I/O area to one or more partners. The direct data exchange is based on PROFINET with IRT and
isochronous mode.
The data exchange takes place via transfer areas.
Direct data exchange between two S7-1500 CPUs (1:1)
The figure below shows the direct data exchange between two S7-1500 CPUs. The output
transfer areas of the sending S7-1500 CPU correspond to the input transfer areas of the
receiving S7-1500 CPU.
① Transfer relation between the user program and the transfer area. The user program and the transfer areas ex-
change input and output data via this path.
② Communication relation for direct data exchange You configure the communication relations in STEP 7. You create
transfer areas for direct data exchange in the properties of the communication relations.
Figure 5-78 Direct data exchange between two S7-1500 CPUs (1:1)
PROFINET with STEP 7
Function Manual, 05/2021, A5E03444486-AL
Functions
5.8 Direct data exchange
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