GW-7553-B / GW-7553-M PROFIBUS/Modbus TCP Gateway User Manual
(Version 1.35, May/2017)
PAGE: 56
DA: Device Address-0x01
FC: Function Code-0x02:read DI
SA(Hi): Start Address(Hi byte)-0x00
SA(Lo): Start Address(Lo byte)-0x00
NO(Hi): No. Of points(Hi byte)-0x00
NO(Lo): No. Of points (Lo byte)-0x10
BC: Byte Count-0x02
4.9 Data exchange example—Modbus TCP
In this example a Modbus master device simulated by a PC program sends query
message and receives response message from a Profibus master via the GW-7553-
B gateway.
In the following example the SIEMATIC S7-300 CPU313C-2 DP and GW-7553-
B are used. The configuration and communication is done by the program “Step 7
Manager” provided by SIEMENS.
Step 1: Copy the GSD file and assign the GW-7553-B a valid station
address (Please refer to the section 4.2 GSD file).
Step 2: Connect GW-7553-B and PC ,PLC below.