boolean troubleshooting

[vaib]

Hello every body I am trying to make a loop, and i got stuck at the following part. please suggest an appropriate solution: I want to make a loop which starts saving data when it recieves a 'True' from a boolean control and then bypasses the loop itself and keeps on collecting data irrespective of the boolean output. I am attaching my 'vi'

[lmtis]

You could make a flat sequence with the loop in frame 1, and your data collection code in frame 2. 

[vaib]

Thanks for replying however I would be obliged if you could explain this more elaborately. Actually if you have a look at my vi you would notice that there is only one while loop which contains both the daq and the operators, so i was wondering if i am better off with two loops or one. Vaibhav

[Dennis_Knutson]

To latch a Boolean, you just need a shift register as shown below. Also, from what I can tell, you have no way to stop the program unless you use the Abort Button on the toolbar. Wire a stop button to the stop input of the DAQ Assistant. For clarity, you might also want to convert the output of your Greater Than function to a single Boolean. I thoroughly despise dynamic data because it just makes it harder to see the actual data type.

Message Edited by Dennis Knutson on 06-13-2008 01:28 PM

Message Edited by Dennis Knutson on 06-13-2008 01:31 PM

[lmtis]

What is the purpose of the numeric greater than 1?

[vaib]

thanks a ton to everybody for replying. However..I am really sorry..coz. i am a rookie. I am not sure of the shift register option because i donot have a loop around my boolean control however the idea of making the two boolean controller a single one was great. I was thinking the abort button to be the stop so i think i note that point too. As for the 1 , actually i have a voltage channel number 3 in my daq which is measuring voltage from a source when it goes above 1 v i start the data writing process to my file. vaibhav

[Dennis_Knutson]

What do you mean you don't have a loop around the Boolean? It's there in the VI you posted. The while loop is that squarish object around all of your code.

Never use the abort button to stop a VI. See this.

[vaib]

Thanks a ton dennis, that was really helpful now the code is running just fine.

[vaib]

Hi I am just having a small problem executing Dennis's solution. The vi does not allow me to wire the boolean or function to the shift register saying that i am connecting a dynamic data source to a boolean sink Kindly advice me how to sort out this problem i am attaching a picture and a copy of the vi.

[Dennis_Knutson]

As I said above, 'convert the output of your Greater Than function to a single Boolean'. That is done with the Convert from Dynamic Data function. When you configure it, select Single Scalar and Boolean data type.