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Siemens AG
Entry type: Application example, Entry ID: 40622389, Entry date: 10/18/2010

Ethernet Communication: Data Exchange S7-1200 <-> S7-200 (CE-X20)

  • Entry
  • Associated product(s)

Automation task:
Deterministic data exchange (e.g. for time synchronization) shall be enabled between an S7 200 master controller and several S7-1200 slave controllers.

Figure 01

The S7-200 controller is configured using the STEP 7 Micro/WIN V4.0 SP7 programming user interface.
The S7-1200 compact controllers are configured using the STEP 7 Basic V10.5 SP2 programming user interface.

Automation solution:
Common basis for data exchange between S7-1200 and S7-200 via Industrial Ethernet is the S7 communication protocol. For the S7 communication the S7-1200 offers the passive server functionality which provides read or write access to data. In S7-200 the configuration process occurs as a client via the Ethernet wizard in STEP 7 Micro/WIN V4.0. With the Ethernet wizard the respective connection partner as well as the exchanged data is established for both sides (client and server). A maximum number of 8 simultaneous connections can be configured with the Ethernet wizard. The deterministic data exchange with clock time synchronization for maximal 8 server is shown.

Figure 02

Client and server have one send and one receive area. For S7-200 these areas are created in the V-memory (VB_Send and VB_Receive). For the S7-1200 the data blocks are used (Receive_DB and Send_DB). At a synchronization request the client reads the system time and sends it to the first server together with the user data. This server synchronizes its system time with the received clock time of the client. The user data of server 1 is then received. This user data of server 1 is then saved at a given location in the variable buffer of the client. This procedure is repeated with the subsequent server. After the data exchange between client and the last server the client starts the data exchange with server 1.

Startup Code
For the startup we offer you software examples with test code and test parameters as download. These software examples support you in the first steps and tests of the configuration examples. They enable a quick test of hardware and software interfaces of the products described in the configuration example.


Content of the downloads


Configuration Example 20 V1.0 (Description) 40622389_CE-X20_v1d0_en.pdf ( 2358 KB )
Startup Code V1.0 with control program for the client controller (necessary software: STEP 7 Mircro/WIN V4.0 SP7) CE-X20_Client_v1d0.zip ( 11 KB )
Startup Code V1.0 with control program for the server controllers (necessary software: STEP 7 Basic V10.5 SP2) CE-X20_Server_v1d0.zip ( 1430 KB )


Contents of the links


S7-1200 System manual 36932465
STEP 7 Basic V10.5 Service Pack 2 39741113
STEP 7 Micro/WIN V4.0 Service Pack (SP7) 33005232





October 2010 First publication