Continuous Serial signal

[Dynamik]

Hi Mlws,

      When I read your post, it sounds like the problem is that the serial output buffer can't be filled during the output operation.  Output stops because the serial-output buffer is empty, then waits some [varying amount of] time for the application to realize the output has finished and to send more data.

What's wanted (?) is to send bytes, continuously and indefinately - with no pause/waiting for the application to re-fill the buffer.  With buffered analog or digital output, NIDAQ makes this easy - the output buffer can be filled during the output operation - but is it possible when using VISA to do serial output?  Is it possible in LabVIEW using some other serial-IO mechanism?

If that's the question, I'd like to know the answer too!

(If that IS the question, I'd look for solutions in other languages, then port the solution to LabVIEW (usually possible) or maybe web-research what kind of serial-buffer control you can obtain through the Win API. (maybe the only solution is not a VISA solution.))

 (causing unacceptable, fluctuating-length pause.)   another you can't keep the serial-output buffer from being emptied, at which point seru" was/is that the Serial output stops

[Dynamik]

... on second thought, it should  be possible, using VISA, to keep the buffer full, no? 

[Mlws]

Chilly Charlie,

Thanks for the Continuous break vi. I tested it and it works perfectly! That was really the answer to all my questions! Checked it with the oscilloscope my self, it does work and sends a continuous signal thus not needing the trouble to send in bit form. It was more than i expected. Now i can get a fixed signal to operate my relay well. Btw, the serial port voltage is enough to power up my 5V relay. It's a reed relay able to withstand 300Vdc switching voltage. 🙂

Thanks again guys.