Easy programming for the DSO Quad

I have made a scripting language environment for the DSO Quad:

http://essentialscrap.com/dsoquad/pawn.html







There is something for the non-programmers also; the example programs include a servo tester, voltage meter and a new version of the frequency response app.

That’s the coolest thing I ever saw on a DSO! I wonder if it could be ported to the DSO Nano as well, although RAM is more tight there. And the sampling HW is completely different, but I still think it would be possible to make some compatible applets. And the Nano is not limited to a 32k slot for its runtime library…

Yeah, I have been thinking about that also. I see no reason why, it would just have a few limitations for the applications (like wavein_samplerate(72000000) will fail etc.), but simple applications like voltage meter and similar should be portable.

Great job!

I’ve found minor bug in calibtarion app. Do You want to be informed about that? (and where?)

Here: https://github.com/PetteriAimonen/QuadPawn/issues

Brilliant.

Thank you.

I love pawn :slight_smile: keep up the good work :slight_smile:

I have just got my DSO Quad and the ability to load new firmware and functionality was one of the major factors why I chose this. The hardware with the metallic case I got actually performs very well and seems to calibrate well and have good bandwidth.



The Pawn scripting method for enhancing further is definitely an area I will be exploring.

Petteri, your development is great, thank you!



A small bug and a little technical question:

  • on my DSO203, the battery symbol is not displayed correctly (the contents of the battery is shifted half out of the shelf)
  • why do we have to push two keys to quit an application (one to close and one to quit)?



    Is there anywhere a description about how the whole thing works:
  • the programs reside on the flash memory and remain only there?
  • what is the limitation on the number of programs on flash, only flash capacity (which is how big)?
  • is a program completely loaded in RAM at runtime? is it compiled, interpreted, or does it use something like p-code which is then interpreted by the PAWN_APP.HEX?
  • what is the limitation on the size of a single program?
  • is there somewhere a list of all functions calls and all parameters which can be used?



    Regards

    Patrick

This scripting add on is going to be great for the Quad. I’ve got my dev environment set up and have a few ideas to try out and will post further hopefully when I have progressed a bit more.



The next bit is just pure speculation to see what the longer term possibilities of this environment are.



I am running the Community main app which seems to take APP1 and a bit of APP2. I am wondering what the technical feasibility of integrating the PAWN environment into the same build with the idea of making it even easier to switch back and forth between them and even potentially allow PAWN scripts to work directly with data gathered from the main host app and enhance that further. I could imagine a loose integration where a key or menu item would allow switching between the two environments. I guess a tighter integration where a PAWN script could be running in parallel may be harder to achieve as the PAWN interpreter would need to be running at the same time as the main app. Apart from making it easier to add specialised measurement calculations, it might be possible to have scripts doing further management functions like battery monitoring.



A variant on this would be whether it would be feasible to create the environment where a PAWN front end gave similar functionality to the community scope app.

Good question (i haven’t noticed it;-)

There’s 2MB flash (spec)

Program have to be compiled (the compiler is included in git repo), you should look at Getting started page.

AFAIK there is no documentation (jet?) but there are few examples (especially Volt Meter) and includes (commented).

I fixed the battery icon bug now. I had forgot to test it with less than full battery :slight_smile:



I guess I could get rid of the second keypress. It’s there because e.g. hello world and other simple applications exit immediately, and I want to see the screen after they exit.

The programs are on the 2MB flash memory. There can be as many as can fit, probably about 20-40 because each app is about 50-100kB.



The programs are in the pawn bytecode. Pawn has a p-code interpreter for ARM that is written in assembler (written by someone else, not me). It is quite fast, only about 5-10 instructions per one emulated instruction.



The programs are loaded to RAM at runtime. However, Pawn has an ‘overlay’ mechanism that is kind of swap. It allows to load programs larger than 32kB. The interpreter will then reload functions from flash as needed, always keeping the most recent functions in RAM.



The program size is kind-of limited by the data size - because data memory is never swapped, you can only have about 20kB of data in order to leave enough space for functions. Of the programs I have done so far, only frequency response app requires the overlays. So I guess programs larger than frequency response have to be a bit careful about memory use.



Only list of functions so far is the .inc files here:

<LINK_TEXT text=“https://github.com/PetteriAimonen/QuadP … er/include”>https://github.com/PetteriAimonen/QuadPawn/tree/master/Compiler/include</LINK_TEXT>

They do have comments, though.

Indeed, that is a possibility worth considering. It may be too tight on the RAM memory, though. Both the main app and pawn require quite much all the available RAM on the device, so it is difficult to make them run at the same time. One could make a key that easily switches between them, though.



Processing data from main app is already possible by reading the files it creates. I have been thinking that a BMP viewer application would be useful if one wants to use the Quad completely stand-alone :slight_smile:

I just finished a simple Spectrum Analyzer using Petteri’s implementation of PAWN and all I can say is that Petteri has provided a great tool. I have started from scratch on many small platforms over the years and this has been the quickest and easiest experience I have ever had in doing this. My little app is called spec_an and can be found with Petteri’s examples at <LINK_TEXT text=“https://github.com/PetteriAimonen/QuadP … r/Programs”>https://github.com/PetteriAimonen/QuadPawn/tree/master/Programs</LINK_TEXT>. Based on what I did I think the very best way to get on top of this is to study a few of the posted programs and then browse through the include files.

Is there possibility to turn off the screen? I haven’t found anything in includes.

I would like to analyse battery discharging process. It takes a lot of time. I suppose backlight use a lot of energy, so if I could turn off the screen I could longer measure.

Not right now. Should be easy enough to add support in runtime once I get around to it (also missing beeper support currently). You can keep the DSO connected through USB if you worry about battery running empty.


I’d add controlling RTC to wishlist - of course if there is RTC on board. Setting time only (without date) would be useful for me, even if I have to set after every power on (or even after application start). I’m working on project (for now “secret” :wink: where I’d like to synchronize asynchronous (user triggered) data dumps with position (from GPS).


Yes, I know. I’m going to check “2xAA USB charger” so for now it’s no problem :wink:

There is RTC, but it doesn’t have backup battery so you’d have to reset it after power-on, just like you guessed.



The get_time() function (which gives millisecond timestamps since power-on) should be accurate.


This is what I’m using as workaround. But this gives me timestamp relative to power on - every time is similar. Of course using “select_filename” I have files in chronological order.



btw. I’m impressed how easy you can write an application. You don’t have to learn PAWN - just use it.

Hmm yeah, I wonder if there is any reasonable solution to this. One common way to easily set RTC of USB devices is to monitor timestamp on files written to USB drive. Then just sync the time right after the write.



Also if I added proper power saving support to the Pawn runtime, it could possibly be left on for a long time. Most power-consuming parts of the system (ADC, FPGA, switching regulator) can be switched off and MCU could go into standby. The standby current consumption should be less than 1mA, giving a few weeks of standby time.



Too bad that they didn’t make use of the RTC in the microcontroller. Would have required just two diodes (to drop 4.2V -> less than 3.6V) if one is happy with LSI oscillator accuracy (can calibrate it right before sleep).