VISA Write/ Read Error

[xolox24]

Hi There,

From what I had seen this has not been posted before.

It seems that the VISA Read/Write error is quite common and after read through a few posts and trying the proposed solutions out I find that nothing works. I am trying to communicate with my motor controller. I have set up the correct COM port and the interface parameters (eg baud rate, parity etc). In the terminal program, Termite and the Measurement and Automation Explorer I can access and send commands to the controller, and it works (the read buffer returns an error but still returns the right reply).

The command format is /1 EN1\r where /1 is the header and address, EN1 enables the drive and \r is the carriage return. Sending the commands in that format works. BUT in the program I wrote I get the infamous timeout error as in the attached picture. I have tried removing the Read VI but nothing works.

Please any help would be appreciated.

Regards,

Richard

[RavensFan · Accepted solution]

I'm quite sure your error (-1073807339, timeout) as been posted thousands of times before.  So if you haven't seen it, you must not have searched.

The string constant in your diagram, what is the display mode for that?  Is it normal mode or \codes mode?  A common error is to have it in normal display and you are sending a backslash followed by an "r", rather than sending a carriage return character which shows up as "\r" when the string constant is shown in backslash mode.

[xolox24]

Yes I did see the 100000000 posts on that error with a fair amount of searching.

Thanks for your help, I didn't realise that the string block with "\r" required that it be set to codes mode. That fixed it.

Regards,

Richard