Modbus over Ethernet/TCP

[xjDu]

Thank you very much, now I have found the problem, but my equipment can only smooth connection for a while unless I keep clicking the OK button at the execution procedures, I think it should be the modbus TCP commands no continuous transmission of reason, I'll try to solve it.

[holly7787]

when i have a device to communicate, usually, i create a separated thread and use a producer consumer loop in this way, if the event queue is empty i process a reading, if it's not empty i process the request, usually a writing. you will not have keepalive problem in this way.

if you have labview installed you can see the pattern http://www.ni.com/white-paper/3023/en/ and try to convert it in labwindows writing your code, is a good programming exercise and will be very useful to write good devices driver

[holly7787]

Hello Jattie, maybe it's too old this thread and you cannot help me.

in your example I don't find the file shared memory, do you remember where to find it?

[Mehmmrsly]

Hi Jattie,

I know that it has been a while for your Modbus TCP project which I just ran across in my search for a Labwindows Modbus library. I opened the zip file that you had attached but it was missing 3 files as follows:

1. Sharedmem.c

2. MATr192.ini

3. WS2_32.lib

Do you still have these files, and if you do, could you share them with me?

Thanks,

Mike Hammersley

[rolfk]

WS2_32.lib is simply the import library for the ws2_32.dll from Windows. You need to install the Microsoft Windows SDK support to get that.