UDP Read error

[trillianguy]

I have an application talking to a camera via UDP using the UDP library from the NI site. I am using LabWindows 7.1 without the patch. The camera has a command port and a data port. I can send and receive from the command port, but get timeout error when receiving on the data port. The application does not send any data to the data port, merely receives image data on that port.

The sequence is:

open command port

Send connect and Play command (includes the data port address)

Listen on data port.

Any reason why the receive port should timeout? I can see the camera sending the data (LED indicator). The camera works with other application software provided by the vendor, so the problem must be in my application.

[Wendy L]

Hello Trillianguy,

You mentioned that you are doing UDP in CVI.  Are you using the Winsock example to perform UDP?  If so, the problem probably lies in the structure of your application or at the Winsock layer.  First, if you are using the example linked above, can you run the UDPRead program and read information from your data port, or do you still get a timeout error?

Thanks.

[trillianguy]

I was able to resolve the problem by including the UDP.c in the code and removing the DLL. The DLL and lib are probably not compatible with version 7.1. The additional benefit is I can modify the read calls add parameter to return the number of bytes as well.

Thanks.