Post trig acquisition (external trig)
Post trig acquisition (external trig), a forum discussion on Cleverscope Mixed Signal USB Oscilloscopes. Join us for more discussions on Post trig acquisition (external trig) on our Other Issues forum.
You must be logged in to post a reply
 Back to Forum Index : Back to Other Issues |
 |
Harold
1 Mar 2008
Posts: 4
I am working with Labview CScope driver.
With an external trig, how can I set a delay time before capturing signal?
I want to trig the CScope 320 externally, wait 10 usec, start to capture signal for 50 usec and transfer the catured signal (50 usec).
This a standard feature on digitizer board. (GAGE, Alazar, National Instruments, Aquitek, ZTEC Instruments. . . )
Need help.
With an external trig, how can I set a delay time before capturing signal?
I want to trig the CScope 320 externally, wait 10 usec, start to capture signal for 50 usec and transfer the catured signal (50 usec).
This a standard feature on digitizer board. (GAGE, Alazar, National Instruments, Aquitek, ZTEC Instruments. . . )
Need help.
bartschroder
18 Mar 2008
Posts: 477
Hello Harold,
We covered this point in an email to you. The start and stop times define the capture period relative to the trigger. So if you set start at 104.2ms and stop at 104.6ms you will capture 400us of signal, with a 104.2ms post trigger delay. Similarly if you used start = -8.6ms and stop = -7.2ms you are capturing 1.4ms of signal, starting 8.6 ms before the trigger. Note that for post triggered situations, we have a 10ns counter counting the post trigger delay, which means you can get use the whole frame for capturing just the bit you want. However for the pre trigger scenario we must capture samples all the way to the trigger so the frame that is captured actually goes from the start time to 0 secs.
Hope this helps!
We covered this point in an email to you. The start and stop times define the capture period relative to the trigger. So if you set start at 104.2ms and stop at 104.6ms you will capture 400us of signal, with a 104.2ms post trigger delay. Similarly if you used start = -8.6ms and stop = -7.2ms you are capturing 1.4ms of signal, starting 8.6 ms before the trigger. Note that for post triggered situations, we have a 10ns counter counting the post trigger delay, which means you can get use the whole frame for capturing just the bit you want. However for the pre trigger scenario we must capture samples all the way to the trigger so the frame that is captured actually goes from the start time to 0 secs.
Hope this helps!
| Back to Forum Index : Back to Other Issues |
|