TCP Server in Halcon example errors after client disconnects

2020-02-27T13:48:47.045000Z

Hello,

Setup: Schneider Electric TM251MESE running the TCP-Server code
With putty I connect to this plc with raw tcp communication on port 4711.

The plc response is Hello World: 100
When I response with Hello World: 100 the response is Hello World: 99 etc.
As expected the value decrements every time the correct response is send back to the plc
The eState variable is switching from Init to Send to Read, Send, Read...

After I close the putty window the state switches to Error then to Init, assuming this is expected behaviour.

When I try to connect again the connection is made, the Hello World: __ string is returned and eState switches to Read.
The next cycle handling this state fails:
The putty window closes.

Setting breakpoints: after executing

TCPRead(xEnable:= TRUE, hConnection:= Connection, szSize:= SIZEOF(sReceived), pData:= ADR(sReceived));

TCPRead.xError is true, eState switches from Error into Init.

Every time I connect again the Hello World: __ string is send again but every attempt to receive (TCPRead) results in an Error then Init.

Only by a cold reset I can connect again and send data back to the plc.

What is happening?
Is there a method to reset the functionblocks in this example?

I tried this example as I need to implement a connection from a robot to this plc.

Are there any other examples of a simple tcp-server arround with some error handling?

Thanks in advance!
Best regards,
Onno

Recent posts to TCP Server in Halcon example errors after client disconnects

TCP Server in Halcon example errors after client disconnects