Counter/Timer

cancel
Showing results for 
Search instead for 
Did you mean: 

signalexpress

I am using a NI USB-6210 to perform digital freq measurements using SignalExpress.  The signals I am measuring may not exist for multiple minutes or even hours.  How (using Signal Express) can I extend the time out beyond 10 seconds or is this not possible.

 

I am using aquisition mode =  "1 Sample on demand" .  If I use any other mode I am not able to log the frequency data.

 

Please let me know if tehre is a solution using Signal Express.

 

Thank you...

0 Kudos
Message 1 of 8
(6,443 Views)

Hi CarbonGen,

 

I can get my counter frequency task to Run Continuously in 1 Sample (On Demand) mode for more than 10 seconds without timing out.  It reads a frequency of 0 for as long as I run it.  Have you selected the Record checkbox under Signal Selection in the Recording Options Tab?  Can you attach a screenshot of your application timing out?

 

 

Brian

Brian G.
0 Kudos
Message 2 of 8
(6,436 Views)

Brian... Thanks for the quick response.  I am workong on this part time Weds and Thursday evenings.  I will double check your recomend then and post screen shots if needed. 

0 Kudos
Message 3 of 8
(6,429 Views)

Brian,

 

 

I can confirm that under recording options I have checked the freq boxes. See screen shot.

 

I have tried to set the min freq as 0 with acquisition mode set to "1 sample on demand"

I get a new error when doing this. See screen shot..

 

Not sure if it is normal but the advanced timing settings are greyed. See screen shot.

0 Kudos
Message 4 of 8
(6,411 Views)

The error you are getting now is because your minimum frequency is set too low.  It needs to be greater than the number specified in the error description box.  

 

Right now you have two counter measurements set up, but each uses 2 counters (ctr0 and ctr1) to perform the measurement.  How many signals are you trying to measure?

 

 

Brian 

Brian G.
0 Kudos
Message 5 of 8
(6,398 Views)

Brian,

 

Yes I know that I need to set the freq to a value greater than the min value asyou state. I think I miss read your earlier email thinking you had suggested to try this.  In any event, even when I set the min freq to some acceptable value, the device still times out.

 

Yes I am reading 2 freq inputs. They are a slow signals but they both have high duty cycle resulting in a very short on time.  I am not abe to read any freq input unless I set the device up to read "2 counters (Large Range)" because of this. The good news is, I don't need to read these freq inputs very often.  Once per minute would actually be often enough.  So sequencing seems to be accurate enough for what I am doing. Despite this,  even when reading a single input the device was still timing out after ~10 seconds.

 

Is this a lmitation pf the 6210 device I'm using?

When you said you could get the device to read 0 Hz for an extended time, was this done on a 6210 as well ?

Do you have the "Advanced Timing" Section greyed out like I do ?  Is that normal ? 

Even if greyed out, does yours show 10 seconds as the timeout ?

 

Appreciate your feedback and dialog on this. 

 

 

 

0 Kudos
Message 6 of 8
(6,383 Views)

I plan to inject a fake signal at 1 cycle every 8 seconds.  Still would like answers to my questions if possible please....

0 Kudos
Message 7 of 8
(6,351 Views)

Your USB-6210 has two counters, so you can only perform a single 2 counter (large range) frequency measurement.  For two low frequency measurements, you can change your two tasks to each use the 1 counter (low frequency) mode on ctr0 and ctr1.  These will use the default gate terminals of the two counters.

 

6210 Counters.JPG 

 

For more information about configuring counter measurements, please see NI USB-621x User Manual:

http://digital.ni.com/manuals.nsf/websearch/5452CD6A491AC0288625757B0065EA32

 

 

Brian

Brian G.
0 Kudos
Message 8 of 8
(6,341 Views)