Hi users

 i want to count something by image processing.

 image processing program use c language.i connect plc s7_400 to opc. 

How can i send or recive data from opc and c language?

Hello Poryabaghal;

You are using an OPC server on the S7-400, from Simatic Net or a 3rd-party provider? And you want to use an OPC client to read data from the PLC to write in a PC?

There are many available sample programs to develop an OPC client in C on the web, one thing you must determine is what "flavor" of OPC you are using for the server: OPC DA, OPC UA, OPC XML..  One example:

https://www.opclabs.com/products/quickopc/languages-and-tools/c-cpp

Hope this helps,

Daniel Chartier

Thanks so lot

I just want to to connect "imageprocessing software" to opc as a therdparty.

 i nedd an simple example for c languege

Hello

for AnsiC you will not find an example on Siemens sites, there is only one for C#:

https://support.industry.siemens.com/cs/de/en/view/109737901

And for a OPC UA Client in C you can search at google

Bye Murof