howto capturing edge until the last one

Post discussions on projects you are working on
Post Reply
pupillo
Newbie
Posts: 0
Joined: Wed Jan 27, 2016 9:13 pm

howto capturing edge until the last one

Post by pupillo »

Hi, I've a digital signal which at a certain point stops working (it doesn't change anymore) and I'd like to capture the latest period of time (let's say 10 microsec) until the last edge, in order to see what happened before it stopped. I tried with "repeat" trigger mode but I'm not sure it does what I need. I want to be sure that what I see in the waveform is the latest part, without missing anything.
How should I do?
Regards
Pupillo

Martyn
Site Admin
Site Admin
Posts: 4491
Joined: Fri Jun 10, 2011 8:15 am
Location: St. Neots

Re: howto capturing edge until the last one

Post by Martyn »

It would be helpful to see what the signal looks like, a sketch will do, if you can't capture with the scope.

Please let us know which scope you have as well.
Martyn
Technical Support Manager

pupillo
Newbie
Posts: 0
Joined: Wed Jan 27, 2016 9:13 pm

Re: howto capturing edge until the last one

Post by pupillo »

Hi,
it's a simple MOSI output from an SPI bus with a clk running at 12Mhz. So, 0 / 3.3v . Very good signal, no noise. As the clk is at 12mhz, my signal can change as often as 1/12Mhz.
Regards
Pupillo

pupillo
Newbie
Posts: 0
Joined: Wed Jan 27, 2016 9:13 pm

Re: howto capturing edge until the last one

Post by pupillo »

Sorry, I was forgetting, my scope is a 3206D
Regards
Pupillo

Martyn
Site Admin
Site Admin
Posts: 4491
Joined: Fri Jun 10, 2011 8:15 am
Location: St. Neots

Re: howto capturing edge until the last one

Post by Martyn »

Sounds like you need to use one of the two Dropout triggers from the Advanced Trigger menu.
Martyn
Technical Support Manager

Post Reply