M340/Communication/Modbus-TCP/

[Lyapunov 0]

Hi, I have a problem with my communication, i have a PLC M340 with a communication module NOE0100. I used commands like Read_Var and Write_Var to read and write in registers. The communication works well, but my only problem is when i put the power off and then i restart the system again, the communication is not working, and i have to push the reset button wich is situated in the front of the NOE0100 communication module, then i get my communication like before. I used a timout parameter and i used a cold-start procedure (as i know) but any of them are not working. Any one can give me a simple solution or perhaps the main problem is specifically the card is not working well (the hardware)... Thanks

[billysmithde2 1]

I doubt it is the hardware, more likely user code on startup. However, is all the firmware up to date? It is possible there are firmware bugs. There are a number of selections available for startup checking - may I suggest Automatic Start in RUN and also a test of %S21? If you have done these and it still does not work, can you post your program?

[Pipe 0]

I have had a similar problem using the Read_Var command to solve it I had to downgrade the firmware in the CPU to 1.0 . The problem seems to be confined to programs that were done under UP 3.0 and reused under later versions we are going to rewrite one of our programs using UP 6.1 and see if we still have problems with the 2.0 firmware. I have never had to change the NOE firmware. Edited 9 Sep 2011 by Pipe