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AWG only triggering once despite multiple trigger conditions
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anton-firmware
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- Joined: Wed Dec 20, 2023 1:17 pm
AWG only triggering once despite multiple trigger conditions
Hello lovely people,
Just wondering if I'm doing something wrong here - I've a Picoscope set up the AWG to trigger on the falling edge of an MCU pin, I expect it to trigger everytime this condition happens but it seems to only happen once (see attachment below), what am I doing wrong?
Just wondering if I'm doing something wrong here - I've a Picoscope set up the AWG to trigger on the falling edge of an MCU pin, I expect it to trigger everytime this condition happens but it seems to only happen once (see attachment below), what am I doing wrong?
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Re: AWG only triggering once despite multiple trigger conditions
Hi anton-firmware,
Here are some answers for you:
Practical answer
Your Capture period is too long for the period between Trigger events.
If you only need to see one generated waveform in your Captured data, and you have some way of verifying that you are generating waveforms for each trigger that doesn't require looking at the Captured data on the same Scope (e.g. if you have 2 scopes, so that you can set up long captures on the other scope, to see successively generated waveforms) then the easiest/quickest way to solve this is to just keep reducing the TimeBase (Total Capture Time) one step at a time until you get your successively generated waveforms.
If you don't have any way of verifying that you're generating waveforms for each Trigger, but you don't need to see successively generated waveforms in the same capture, then you could just set the capture period to between 1/2 to 3/4 of the Trigger period, and be safe in the knowledge that your waveforms are being generated on each Trigger.
If you need to see successively generated waveforms in the same capture and you only have the one Scope, then you could try increasing the number of waveforms generated, per Trigger, by the Sig Gen, and then adjusting the Waveform frequency to match the quantity and frequency of the Trigger events (assuming that they are occurring periodically).
Technical Answer
The issue is that when you set the AWG to use the Scope Trigger, you're synchronizing the Generation of a Waveform to a Trigger event that Triggers the capture of complete Timebase of data. There is only one Trigger that the Scope has and when that is used to capture a window of data, it can't be used again until all of the data for the window has been captured. So, although you may have additional Trigger events occurring during the Capture, they can't fire the Trigger until the Capture is complete, and the Trigger has been re-armed.
If you want the Waveform to be generated on every Trigger event, then you need to use a small enough Timebase, i.e. the following needs to be True:
Timebase < (Interval between Trigger edges - Trigger re-arm Time).
Regards,
Gerry
Here are some answers for you:
Practical answer
Your Capture period is too long for the period between Trigger events.
If you only need to see one generated waveform in your Captured data, and you have some way of verifying that you are generating waveforms for each trigger that doesn't require looking at the Captured data on the same Scope (e.g. if you have 2 scopes, so that you can set up long captures on the other scope, to see successively generated waveforms) then the easiest/quickest way to solve this is to just keep reducing the TimeBase (Total Capture Time) one step at a time until you get your successively generated waveforms.
If you don't have any way of verifying that you're generating waveforms for each Trigger, but you don't need to see successively generated waveforms in the same capture, then you could just set the capture period to between 1/2 to 3/4 of the Trigger period, and be safe in the knowledge that your waveforms are being generated on each Trigger.
If you need to see successively generated waveforms in the same capture and you only have the one Scope, then you could try increasing the number of waveforms generated, per Trigger, by the Sig Gen, and then adjusting the Waveform frequency to match the quantity and frequency of the Trigger events (assuming that they are occurring periodically).
Technical Answer
The issue is that when you set the AWG to use the Scope Trigger, you're synchronizing the Generation of a Waveform to a Trigger event that Triggers the capture of complete Timebase of data. There is only one Trigger that the Scope has and when that is used to capture a window of data, it can't be used again until all of the data for the window has been captured. So, although you may have additional Trigger events occurring during the Capture, they can't fire the Trigger until the Capture is complete, and the Trigger has been re-armed.
If you want the Waveform to be generated on every Trigger event, then you need to use a small enough Timebase, i.e. the following needs to be True:
Timebase < (Interval between Trigger edges - Trigger re-arm Time).
Regards,
Gerry
Gerry
Technical Specialist
Technical Specialist
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anton-firmware
- Newbie
- Posts: 0
- Joined: Wed Dec 20, 2023 1:17 pm
Re: AWG only triggering once despite multiple trigger conditions
Hi Gerry,
Thanks for the reply! That's very helpful.
Setting the time base lower did indeed achieve the effect I desired!
Have a lovely Christmas!
Thanks for the reply! That's very helpful.
Setting the time base lower did indeed achieve the effect I desired!
Have a lovely Christmas!