topic Re: multiple timer+saving to file in LabVIEW

multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 17:12:32 GMT

Hi guys,

I'm new to here and LabVIEW, and I'm trying to design a program with multiple timers. The user clicks the first button to start the timer, and upon clicking the second button, it stops the first timer, logs it, and starts a second timer. And so on with the third and fourth buttons.

I have a VI designed, but it doesn't really work, and I'm not sure why. Could anyone suggest possible fixes? Thanks a lot.

Re: multiple timer+saving to file

Harold_Timmis — Tue, 10 Nov 2009 17:23:07 GMT

well, you only need one while loop and on event structure for your program

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 17:30:00 GMT

I'm not sure what you mean. How would it work with only one event structure? Could you be a little more specific? Thanks.

Re: multiple timer+saving to file

Harold_Timmis — Tue, 10 Nov 2009 17:38:44 GMT

the reason you are having errors is:

your events are not filled you have to chooses acontrol to go with a event such as:

ok button, value change

Re: multiple timer+saving to file

Harold_Timmis — Tue, 10 Nov 2009 17:45:20 GMT

this is an error:

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 18:01:42 GMT

of coarse, you could just use the elapsed time vi from the timing palatte, use property nodes to enable and disable the buttons, and avoid having all those pesky event structures run in series (by diabling the buttons until the prerquiste event occurs you can combine the structures into one.) makes for cleaner code-but comments should be used to clarify the vi function. Better yet- use the vi discription!

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 18:17:04 GMT

Thanks for the tip.

I filled in the empty event structures, but I think there's something wrong with the design of the program in general.

I'm getting 0.00 0.00 0.00 on the log, instead of actual times.

Is there something wrong with my timer design?

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 18:37:07 GMT

In case anyone wants to try running it, I have the "fixed" version attached.

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 18:37:25 GMT

Yep-

time isn't an integer its a number of mSec.

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 18:43:27 GMT

Woah!

OK- its not good to have the same event handled by two different loops and I cannot understand why you would change the timeout value when "Button" goes true. Back to the drawing board for this.

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 18:56:23 GMT

Sorry, let me start over:

I was browsing old threads and I found a VI to create a timer. Please see "before.vi" However, I didn't want it to output onto an indicator, instead, I wanted to output the total time onto a file, and I changed it to "after.vi".

However, that change doesn't work. Could you guys advise on what I should do to get it to work as I want it to? I think I can figure out the cascading thing in the OP after that.

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 19:01:58 GMT

See comments above

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 19:08:08 GMT

How would I get the values to "save" over to the stop event?

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 19:12:24 GMT

wire them

Re: multiple timer+saving to file

johndoe3344 — Tue, 10 Nov 2009 19:15:11 GMT

Got it!! Thanks!!!!

Re: multiple timer+saving to file

JÞB — Tue, 10 Nov 2009 19:19:01 GMT

Those tunnels set to use default if value if unwired can be a pain in the neck sometimes.

I've found its a good practice to use them sparingly and only for states that really don't matter. Glad to help!

Re: multiple timer+saving to file

GregFreeman — Tue, 10 Nov 2009 19:49:20 GMT

Jeff Bohrer wrote:
Those tunnels set to use default if value if unwired can be a pain in the neck sometimes.
I've found its a good practice to use them sparingly and only for states that really don't matter. Glad to help!

I knew my comment would be proven true eventually! Use default value takes down another!