Serial VIs

[Satiro]

Hi!!
I'm working with serial VIs to operate a step motor. I test the communication with a simple serial interface (PROCOMM) and the step motor works fine. But when I use LabVIEW it doesn't work. The configuration is the same, and I can write and read correctly, but the step motor just don't move as when I use PROCOMM. Anybody have a idea of what could be wrong?? The VI I'm using goes atached.
Thanks!

[Rob Cole]

Your program looks quite servicable. Have you tried the program with a loopback adapter? Did you remember that COM1 is port 0? Have you tried it on different ports? Is your output string properly terminated? Procomm may output your string with and EOL on the end. Add an EOL in your program and see what happens.
Just a few thoughts on what could be happening. With the information I have so far, I would suggest checking the port number and the termination character. Then try with a loopback adapter to make sure that data is being sent correctly.
Let us know what you find out.

Rob

[aderogba]

I ran your vi as it is on my system without any problem. In addition to Rob's suggestions, consult the step motor manual for the terminating character (EOL, CR, etc.). Anytime your hit the "return" key in the "string to write" control, a LF is added, to prevent this from happen, I'll suggest you change the display to Hex until you resolve the problem.

[Satiro]

Thanks for the help!!

The problem was just that it needs a 'carriage return' constant after all commands to properly end the line. It seams that procomm automatic insert that character.

Problem solved! 🙂