reseeting data from daq every second

[.aCe.]

Do you have the details of the error by any chance? Also it would be useful to know the model number of the counter you are using.

[richardmp]

the part number is 995-0104 issue D turbine flow rate sensor ft 110 series

[.aCe.]

Part number of the counter (DAQ device)

[richardmp]

I havn't the foggiest idea of how to find the daq device number. I just can't get my head around why it wont work. The timing progam works fine with sending out the pulse every second. My thought is that it must be a issue with the shift register as it is minusing the value in the now from the value from one iteration previous which is negligable.

[.aCe.]

In the DAQ assistant setting, if you click on the >> button you should see the details of the device.

Also make sure that you select a clock source in the advanced timing tab. THIS SHOULD NOT BE THE SAME CHANNEL as before, for example if you chose Ctr0 above, you cant chose Ctr0InternalOutput.

Try running this, if you are getting an error click on the details button and post the contents.

[richardmp]

i am unable to select ctrlinput 1 as the source. instead i get "pf10." i try running with that and get the error

Error -200077 occurred at DAQ Assistant



Possible Reason(s):

Requested value is not a supported value for this property.

Property: SampTimingType
You Have Requested: Sample Clock
You Can Select: On Demand

[SimonH]

Richard,

I was off the mark on my last post -- I didn't catch that you were doing a counter measurement.  If the VI you posted was giving you good counter readings then I think this might be along the lines of what you are looking for:

I didn't understand what your additional logic was doing -- to me it appeared you were checking to see if the time had changed or not and selecting either the current or the previous reading based on that check.  This seemed unnecessary since you know the loop is iterating once per second so this check will never evaluate to be true.

~Simon

[richardmp]

unfortunatly i have an older version of labview so i couldn't access the VI you uploaded. I was considering the problem last night and i thought..is there a way of building up a data table based on the boolean false/true sent from the timer program?

The idea being that as the dq continues to count up and up and each time the timer progam sends [false] it would record the current value. i would just be able to subtract the present value from the previous second ( and repeat for length of experiment) in excel. Or would there be a way to have this process run in labview itself?Heres a rudimentry flowchart to help illustrate

DAQ [COUNT]------[has a timer sent false]- <Y>-------[log result]

                                          ^                     |

                           [has a timer sent false]-<N>                           

[is there a previous value in the array] <Y>-[subtract previous result from current]---[log result]

[SimonH]

What is the timer for in your logic?  The loop will only iterate once per second -- it seems to me that you want to log a data value on every iteration.  The code you posted previously checks to see if the current time is equal to a past time which will never be true.

The code in the screenshot I posted will build a data table with the time (in seconds) in the first column and the amount the acquired counter signal has changed since the previous second in the second column.  I didn't change any of the settings in the DAQ Assistant so you should be able to recreate the VI from the screenshot.