Write to Measurement File Express VI: file name prompt

[klara]

I am using the Write to Measurement File express VI to write some data.

Even though I have not selected "ask user to choose file" and have set a default filename, the vi still prompts me to choose a file. I tried restarting my pc and it used the default filename the first time and then went back to prompting me. I have set the default to overwrite my existing file each time, so I don't understand why I keep being prompted. If you look in the express VI the "ask only once" radio button is selected and greyed out, but I don't know why; I didn't select it.

(I have the express VI in a while loop and want it to write a line of data to the file each time the loop executes, so it's not convenient to be prompted for the filename each time)

I'm sure this is my own silly fault but would appreciate some advice

Thanks, klara

[Tobin]

Klara,

I've just tried your vi. I seems to work fine for me. The "Write to Measurement File" does its job as intended. While the loop is running, I get no prompt for a file name and the target lvm file continues to increase in size. After I click "Stop and Write Log File", the "Format into File" function executes and does prompt for a destination file. It does not have its "Input File" terminal wired to anything so it pops up a dialog box.

[JeffBoettcher]

I'd suggest changing the mechanical action of your stop button from "Switch When Pressed" to "Latch When Released".  This might be the only problem.  If you didn't manually change your stop button back to false before running again, your loop would run once and stop, and you'd immediately see the file dialog from the Format Into File function.  Changing the mechanical action would prevent you from needing to manually change it back to false before the next run.

Message Edited by Jeff B on 02-07-2008 08:48 AM

[klara]

I just wanted to say thanks for the help. The latch advice in particular looks like it will be helpful (I think I changed this recently, which could explain the problem).

Unfortunately all the people I borrowed bits of kit off have called them back for the next week or so, so I can't run my program at the moment! I will reply when I have my data acquisition cards back.