Save file on trigger

Save file on trigger, a forum discussion on Cleverscope. Join us for more discussions on Save file on trigger on our Questions forum.

Back to Forum Index : Back to Questions   RSS

2 Oct 2009
Posts:

Hello folks,

I´m quite new using clever scope but I´me really interested in using it with my application prototype. I have here with me an 100MHz and 12-bit model.

As I work with doppler ultrasound signals, one of the features that I really need to work properly is the save on trigger feature. I setup an experimento to evaluate it performance and configurate my ultrasound card do generate pulses with a rate of 1KHz. I have one signal line conected do channel A and the triggering line with the 1KHz trigger conecter to external trigger. I successely saved 5000 files using the save on trigger features. My questioning is about the files saved. I´m worried because it took me like 20 minutes to save all the files, but as my trigger happens with a frequency of 1KHz it should take just 5 seconds to buffer the signal.

I´m not sure if all the files represents continuous triggers with out missing any triggers. Can anyone tell me exactly how does it work?
In my application I need to be sure I didn´t missed any triggers. I would appreciate if anyone could explain me how could I check if the files were saved one for each trigger without missing any.

If you need any other information please let me know.

Sorry about the poor english.

Thanks.

2 Oct 2009
Posts: 401

Hello Bruno,
if you have saved on trigger, and the trigger is running at 1 kHz, you will most certainly be losing triggers. The transport system, and the file saving system are much slower than this.
If you want to save a sequence of triggers a better way is to save multiple frames. You can have up to 2998 triggered frames capture as part of one sequence. The approach is to:
1. Use Settings/Acquisition settings, and set the number of frames to 2999. Just for the moment, leave Frames Per Capture as 1.
2. Set up the Cleverscope the way you want it to capture one triggered capture. The total scope graph duration must be less than 800us to allow for the 200us frame-to-frame setup time. If you make it longer than 800us, you may either get two events in one frame, or miss a trigger.
3. Now use Settings/Acquisition Settings, and set the Frames per Capture to 2998.
4. Now click on the 'Single' trigger button. Your acquisition unit will now automatically capture 2998 triggered frames one after the other. If you have less than 2998 triggers available, use a lower number. The acquisition unit will wait until all triggers are captured. If you want to abort the capture, hit single again, and only frames captured so far will be in the acquisition unit.
5. You can now review each frame captured if you wish, by either clicking the Current Frame number up or down (a smaller number is older frames, the highest number is the most recent frame), or type in a number directly.
6. If you are happy with the capture, click the drop down menu to the right of the 'Get Frame' button on the Cleverscope Control Panel, and select 'Seq'.
7. Click 'Get Frame', and all the whole captured sequence will be transferred to PC memory.
8. Now you probably want to save them for export. Do a 'Save As Text', and the save will save all the frames to a text file, with a header that tells you the number of samples per frame, and number of frames. You can do the same for binary.

Good luck!

The Save on Trigger feature you have been using waits till a newly captured frame is captured and transferred and then does the save. This takes many milliseconds, and therefore cannot support a 1 kHz save rate.

6 Oct 2009
Posts:

Thank you very much for your help. It was exactly what I needed and luckly 2998 frames are enough for a prototype.

I tested it today and it solved my problem.

Thanks again.
Bruno
Back to Forum Index : Back to Questions   RSS
You must be logged in to post a reply



You need to Register or Log In before posting on these forums.

×

Your shopping cart is empty.