New, trying for a simple timer

Question

I'm new to Labview and I'm trying to make what should be a simple timer.
Specifications:
(1) A "Start" button starts the timer.
(2) A "Stop" button stops the timer.
(3) A knob controls the timer duration.
(4) Something (right now it's just a sine wave generator) runs while the timer is running.
(5) A status LED lights while the timer is running.
(6) The LED and the "something" in #4 turn off when the timer isn't running.
(7) The timer does not run when the VI starts up.
(8) The timer may be turned on or off multiple times while the VI runs.
I can't get #2 and #7 to work.  The Elapsed Time VI keeps running, so putting my Stop button together with the Time Has Elapsed wire on an "Or" operator doesn't work.  Further, upping the knob value (say, from 2 s to 7 s) after the timer runs out will turn everything back on (because the new, later time hasn't arrived yet).  As for #7, I'm not really sure what to do about that.
Here's a picture of my latest.  Edit: The True condition is nothing more than a False constant wired to the "Busy" LED.
Message Edited by DJDDA on 09-29-2007 11:24 AM
Message Edited by DJDDA on 09-29-2007 11:25 AM

Answer 1

Sorry, I misunderstood.
Here's one possible solution. Yes, the big loop currently runs at near infinite speed, consuming all CPU. Typically, you want to place a small wait (e.g.50ms) to make the loop time reproducible between machines and limit CPU use.
You are also generating 100 points, but you are only displaying one. Seems like a waste.
Why are you using tiny font on the front panel and arbitrary color distinction (everything is red!). Also, the classic controls are a bit ugly and outdated.
You should also remember that LabVIEW 8.5 is very new and most here don't have it. If you would convert your VI to 8.0 before attaching, many more can inspect it.
LabVIEW Champion . Do more with less code and in less time .
Attachments:
ScinPan1MOD.vi ‏57 KB