Pegaia

Hi,

Here there are a sample project and some tips for implementation of MODBUS TCP with S7-1200:

1 - Pre requisites: STEP 7 >= V11 SP1 and S7-1200 FW >=2.1

2 – Documentation: the help on line of the blocksMB_SERVER and MB_CLIENTare the best way to get information about these blocks.

3 – Programming:

3.1 – On MODBUS TCP server

Use MB_SERVER instruction on the server:

Ports: as default you can use 502, however it is possible to use any ELSE ports already
used by S7-1200 (20, 21, 25, 80, 102, 123, 5001, 34962, 34963 and 34964).

Each connection needs a block call (with different instance DB, ID and port)

3.2 – On MODBUS TCP client:

Use MB_CLIENT instruction on the client:

Each connection need a block call (with different instance DB). ID and port must match with the server).

4- Status 7002 = meaning that there is no client connected.
Attachment:MODBUSTCP.zip (2281 Downloads)

How do you program the TSEND_C and TRCV_C instructions for open user communication over the integrated PROFINET interface of the S7-1200 CPU?

New question published by vaggmin is split to a separate thread with the subject Connect three s71200.

Best regards
Min_Moderator