Data Interchanger With The Dp Master; Principles Of Data Transfer Between The Dp Master And The Et 200S - Siemens SIMATIC ET 200S Manual

Advantages
Advantages of user-defined address allocation:
S Optimum utilization of the address areas available, since "address gaps"
between the modules do not occur.
S When creating standard software, you can specify addresses that are
independent of the configuration of the ET 200S station.
3.3

Data interchanger with the DP Master

User data transfer via an intermediate memory
The user data is located in an intermediate memory in the IM 151-7 CPU. This
intermediate memory is always used when user data is transferred between the
IM 151-7 CPU and the DP master. The intermediate memory consists of a
maximum of 32 address areas.
DP master

Data transfer between the DP master and the ET 200S via an intermediate memory in the
IM 151-7 CPU
 Data transfer between the IM 151-7 CPU and I/O modules
Figure 3-5 Principles of data transfer between the DP master and the ET 200S with the IM 151-7 CPU
Address areas for user data transfer with the DP master
The ET 200S provides the PROFIBUS-DP with a maximum of 244 bytes of input
data and 244 bytes of output data. This data can be addressed in the intermediate
memory of the IM 151-7 CPU in up to 32 address areas.
An address area contains a maximum of 32 bytes. A maximum of 244 bytes is
available for input and output data.
The address area begins at 128 by default. The data is entered with "address
gaps" starting at address 128.
ET 200S IM 151-7 CPU Interface Module
A5E00058783-04


PROFIBUS-DP
ET 200S as DP slave
IM 151-7 CPU I/O modules

Intermediate memory
Addressing
3-5