Instructions

4.3. How the Data Exchange Works
Figure 9. The Communicator internal memory areas
The data exchanged between the Communicator and the serial subnetwork and the high level network resides in
the Communicator internal memory buer.
To exchange data with the serial subnetwork, the high level network reads and writes data to the Communicator
internal memory buer.
The same memory locaons are exchanged on the serial subnetwork.
The memory locaons are specied when conguring the Communicator, using the Communicator built-in web
interface.
The Communicator internal memory buer is divided into two areas: Input data and Output data.
Input Data
This Input data area is read by the high level network.
The Communicator can handle up to 244 bytes input data.
Output Data
The Output data area is read/wrien by the high level network.
The Communicator can handle up to 244 bytes output data.
4.4. Data Integrity
A snapshot of the process data buer between the Modbus Client and the server interface is used during the
operaon of execung all the transacons within one cycle.
When the cycle is completed, the process data available on the server interface is updated and a new snapshot is
created for the next cycle.
Anybus
®
Communicator
™
- PROFIBUS to Modbus RTU/Serial How the Data Exchange Works
Page 12 of 134 SCM-1202-177 1.2