Running 5204 device, in PicoScope version 6.14.23 and 29 the External Trigger Level cannot be changed anymore, it's greyed out. In version 6.13.15.4081 it was possible to change it.
Looks like a bug introduced in 6.14 with 5204 device (at least).
I apologise for the delay in looking into this. Because of Covid and working from home, I would need to check this at the office, which I will do tomorrow.
I work from home too, if there's anything I can assist (remote session to my scope is possible), please let me know.
If you can also check zooming that looks weird to me, I would appreciate very much. Please see the screenshots. This's a zoom from the signle-shot. Is this an expected image? When there is a constant triggering, the zoomed image is OK.
Thanks for the offer. Unfortunately we can't use Remote sessions as part of our IT policy. Also, I'm going to have to delay my office visit until next week.
What I can tell you though is that what you are seeing in the blocky looking image is normally a view of zoomed in data that has been scaled for the zoom level, which is what you would expect to see in Slow Sampling mode until the capture is complete for a whole screen of data. But this is not what you would expect to see in Fast Sampling Mode (which is what you were using).
Hi Gerry,
Thanks for the support. Until you can check the External Trigger issue I can still use older version of the S/W where external trigger works fine.
I would like to show another screen shot for the issue with zooming. In this picture I have just moved the zoom rectangle in the Zoom Overview box to the right. Two issues:
1. The plots are not displayed correctly, they are terminated at their previous end position or discontinued when shifted to the left.
2. The position of the zoom rectangle is incorrect. It does not follow the mouse pointer.
All that gets fixed immediately after the next triggering occurs. Actually you can see these problems only in Repeat mode with somewhat rare bursts at the probe. Problem does not occur in a Single mode, though.
All the above is tested with 5204 running 2.1.47.2276
Regarding zooming with the Repeat Trigger I wasn't paying attention to your actual triggers for the Timebase setting that you have, when testing this out on another PicoScope.
In your setup with the one pulse displayed (in your original image) you can see that there is no second pulse. What is happening is that, as you have it on repeat trigger, there is still an active trigger on the scope that is waiting to fire, this means that if you move the zoom around, zoom in further etc the software can't get new aggregated data from the device to refresh the display. As soon as the trigger fires the software can get the new aggregated data and so the screen will update.
So, there actually is no issue with the your particular PicoScope when using Repeat Triggers. If you connect your Signal Generator to an input being used for the trigger, and use the default waveform frequency of 1kHz, you will see that you can zoom in and out without any blocky display effects. This because the triggers are occurring at a high rate so, as soon as you select a zoom level a trigger will fire and the aggregated data will be sent to update the display.
Thanks for clarification, Gerry,
As far as I understand, In the Single mode there's no such issue because trigger is not actually waiting, correct?
In both cases there's all the data the scope needs, as it can be seen in the "zoom overview" box, however in the Repeat mode it's not displayed because the trigger is busy waiting for the next pulse. Is this right?
Correct, except that, for Repeat Trigger Mode, if the time between the events that generate a trigger is too long, then it will be waiting for the trigger to fire (waiting for the next pulse). So, for instance with the following data file Brief_update_delay.psdata,I have created a pulse in the AWG. So, if you feed the Signal Generator output into a channel input, you should be able to see that, when you zoom in and out of different sections of the waveform, you can see brief periods of low resolution, where the updating is delayed.
In the following data file Longer_update_delay.psdata the low resolution persists for longer, as I've slowed the frequency of the SIgnal Generator by a factor of 100 (and reduced the width of the pulse).
Thanks, Gerry,
But why then the scope is able to display high resolution in the Single mode? Isn't it the same situation as when it is waiting for the next fire? I understand that in the Single mode the trigger is not waiting, it's finished, but I do not get why it should affect displaying.
Sorry, I didn't explain that well. In single Trigger Mode there IS the same issue, if there is a long delay before the capture, it's just that, IN YOUR CASE, it appears that there is no long delay before the first capture, so you don't see that.
Let me explain this in a better way. Think of 3 stages that the hardware PicoScope goes through, as follows:
1/ Not acquiring data
2/ Waiting for the trigger
3/ Waiting for the capture to complete
If you were to connect your PicoScope and start the PicoScope software, it starts in a mode that is automatically running and capturing data with timed triggers. So, if you switch it to Single Trigger Mode it will stop after the next Single Trigger has fired, and we will now be in Stage 1, i.e. Not acquiring data.
You will see that you can zoom in and out of the waveform right down to the smallest detail, with full screen resolution (no blocky images) because the software has all of the data to be able to display the data at different zoom levels in high detail.
So, if you were to now set the input range to ±2V, connect the Signal Generator output to the Channel A input, move the yellow Trigger diamond to the top of the screen, and then Press the green arrow head to start the capture, you now have a trigger set to fire when your signal is generated. The screen will be frozen, waiting for the trigger to fire, so you will have moved to Stage 2. THIS IS THE STAGE THAT YOU ARE NOT SEEING in Single Trigger Mode.
In Stage 2 the previous data has now been wiped from the screen memory, in preparation for the new data that will be arriving from the Hardware PicoScope (there is no point in showing old data that does not represent what you are capturing). All that is left is the data needed to be displayed for the zoom level that you have currently displayed (to show the software and hardware are still working). So, if you now zoom in you will notice that the display is again blocky, because there isn't any data that is more detailed. If you were to now open the Signal Generator and start it, the Trigger will fire (because the rising edge of the signal reaches the Trigger very quickly), and we would be briefly in Stage 3, waiting for the capture to complete, before we return to Stage 1, not acquiring data because the capture has completed. You would now again be able to zoom in and out with full detail being displayed.
If you now start the capture, you will go quickly to Stage 3, where you can again zoom in and out with full detail. THIS IS WHAT YOU ARE SEEING in Single Trigger Mode.
I performed some tests, and I have a simple conclusion for me now, please tell me if I'm wrong:
In whatever trigger mode, when the trigger is armed and waiting for the next fire, there will be bulky zoomed images.
If the trigger is stopped - no bulky images.
If the trigger is constantly running - virtually no bulky images (image is fixed on the next fire).
In the Single mode just arming the trigger somehow ruins data in the memory and the image becomes bulky if zoomed, till the next fire.
Yes, that is correct, but to clear up your statement "arming the trigger somehow ruins data" notice that in your last statement you are essentially describing the same thing as your 2nd statement, i.e. the trigger is armed and waiting for the first fire (also notice my last statement should have been "If you now start the capture, you will go quickly to Stage 3, and then quickly back to Stage 1, where you can again zoom in and out with full detail.").