Java and Labview

[sganap]

Hi,

I have a java program that I want to send a signal to Labview to activate one of the sensors. I have not worked with LabView, do you have a sample code for the TCP/IP how to connect to java?

Any help will be greatly appreciated

Regards

-Sganapat

[Yair]

I haven't done any LV<->Java communication, but using the LV TCP functions is simple and you can find several examples in the example finder (Help>Find Examples).

Basically, you get a byte stream which is represented as a string. Normally, in the LV implementation, the sender calculates the size of the data and sends a 4 byte string (an I32) which tells the reciever exactly how much data it's going to get. That way, you can always read 4 bytes to get the size of the data and then ask for that size. You can do a similar implementation in your code, where you would (for example) always send x ASCII characters representing the length of the data.

You can convert the string to a U8 array using one of the functions from the string palette and (if necessary) you can reverse the endianess of the bytes by using the VIs in the Advanced palette.

I would advise that you stick to sending simple ASCII characters and not try to format more complex data into something that LV will understand.

[sganap]

Thanks that was helpful. That leads me to another question:

If I want to send a digital signal from java to Labview VI to trigger a DAQmx device, that takes in I/O from dev1/port0/line:7.

Any insight will be greatly appreciated.

-Sganapat