Suggestions for improvements to the Propscope
waltsailing
Posts: 40
Hi Hanno,
The propscope is really interesting device, very nice job. I was wondering if a couple of changes could be made. I think these might be able to be implemented within the framework of the existing Propscope.
It would be great if the Propscope had a delayed trigger mode. This would be a new dial that would allow one to put in a value with and set the trigger point well before the actual signal you want to look for. Sometimes in looking at signals you need to trigger on a known event and then delay way out to look at some other event of importance.
This might be implemented as a two part scope display where the first part is around the trigger, and the second is around the delayed section. To implement it, it would require a counter to hold off between the two sections. From what I can tell you sample 1k points to memory. It might be possible to put the hold off at 256 points in, and then just have a counter delay out to then start collecting again for the remainder of the 1k points.
For the Dac, a repeated burst mode would be a great addition. The ability to specify a burst length, and a duration between bursts would be great. For example put out a 100KHz burst of 100 cycles every 500 msec or what every you dream up. Something that might get N 600 point sections out, with a delay starting in the beginning or after the last value by M cycles (M being a large value) and then repeat. Or repeat for K bursts. Or using an external trigger then burst, or maybe even output a trigger pulse on the TV output.
Ideally these two types of functions should be able to be run together so one can see the delayed pulse, but not always as there may be other items of interest inbetween these two.
Could you put in a accumulate mode for the plot. This would be like a persistance where there is a button that gets pushed on the display to enable or clear the persistance, otherwise the clear screen is not called for each new trace. this would allow one to look at an accumulation of signals. Really useful feature. Ideally it would be in both the LSA and the Scope.
Are these types of improvement possible or out of scope from what it practical with this? Maybe they already have been requested.
Thanks,
Walt,
The propscope is really interesting device, very nice job. I was wondering if a couple of changes could be made. I think these might be able to be implemented within the framework of the existing Propscope.
It would be great if the Propscope had a delayed trigger mode. This would be a new dial that would allow one to put in a value with and set the trigger point well before the actual signal you want to look for. Sometimes in looking at signals you need to trigger on a known event and then delay way out to look at some other event of importance.
This might be implemented as a two part scope display where the first part is around the trigger, and the second is around the delayed section. To implement it, it would require a counter to hold off between the two sections. From what I can tell you sample 1k points to memory. It might be possible to put the hold off at 256 points in, and then just have a counter delay out to then start collecting again for the remainder of the 1k points.
For the Dac, a repeated burst mode would be a great addition. The ability to specify a burst length, and a duration between bursts would be great. For example put out a 100KHz burst of 100 cycles every 500 msec or what every you dream up. Something that might get N 600 point sections out, with a delay starting in the beginning or after the last value by M cycles (M being a large value) and then repeat. Or repeat for K bursts. Or using an external trigger then burst, or maybe even output a trigger pulse on the TV output.
Ideally these two types of functions should be able to be run together so one can see the delayed pulse, but not always as there may be other items of interest inbetween these two.
Could you put in a accumulate mode for the plot. This would be like a persistance where there is a button that gets pushed on the display to enable or clear the persistance, otherwise the clear screen is not called for each new trace. this would allow one to look at an accumulation of signals. Really useful feature. Ideally it would be in both the LSA and the Scope.
Are these types of improvement possible or out of scope from what it practical with this? Maybe they already have been requested.
Thanks,
Walt,
Comments
Great ideas! Some I've already implemented-
The PropScope always takes 2 screens worth of data in sample mode- and lets you position the trigger at any point. For example, you can set the trigger at the very beginning and display samples taken between 10 and 20 divisions later. Or set the trigger at the end, and watch samples taken 20..10 divisions BEFORE the event. You can click the "run" button to pause the sampling and then scroll the data back/forth or zoom in/out. It's not possible to look more than 20 divisions before the trigger- but I could add an advanced parameter to delay even more than 10 divisions- but one of my main goals is to keep the PropScope super easy to use.
The function generator firmware already has an option to pause for an arbitrary time between outputting a 600 sample pattern- this would get you pretty close to your goal. Again, I need to expose that functionality so it's easy to use.
I have a prototype of an accumulate mode- would be a different "view"
I'm quite busy with consulting projects and my other products, so I would need to figure out how to make the work worth my time...
Hanno
Thank you for reading the requests,
The ability to keep the propscope simple, but useful is a good goal. As for the need for a delay knob, this is important when one might be looking at serial data with the scope, for example. And lots of other things. I think the ability to trigger the scope and then dial in a delay would be really useful, because you can have the sampling speed up where you need it, but have it delayed from the trigger so you can look at what you are interested in.
If you have a known trigger, such as a discrete bit from a basic stamp, and then want to look at a serial word way out in time, the delay lets you walk the 'view' out to where it is visible. Just changing the time base is not sufficient because you can no longer decode what you are looking for. You could have a 'enable' on a pull down to put up the 'delay view' dial up for this to work. This would be a great feature, and is something that is found in other low end scopes. This is not a very advanced feature found on most scopes, so hopefully you can easily implement it.
Where can I find the instructions to use the N blocks for the 600 sample delay. That might solve my problem. I am using the latest downloaded version from Parallax. I am running PropScope v2.0.2.
I look forward to seeing the accumulate/persist mode.
Thanks,
Keep up the good work,
Regards,
Walt,