Propeller 2 Live Forum - Display, GUI, and Multimedia Options with Raymond Allen -Screen Shot
Bob Lawrence (VE1RLL)
Posts: 1,720
in Propeller 2
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I thought maybe one of the cameras was on...
I'm just glad Ken knows how to do Zoom and got me set up before the meeting...
I thought it was unusual that you had turned your camera off as the speaker. However because your presentation was a tour-de-force of professional looking slides it probably helped us to focus on the material and listen. When I'm viewing a share screen I will shrink the speaker/gallery view to maximize the share screen anyway.
I find that as the speaker you are usually the last person to know that you have audio or sharing problems, or even that your camera is off. This is where it is helpful for the host to interject with a short prompt, just in case it wasn't intentional.
I realized my video was off for the whole presentation. Only the second time for a Zoom for me.
We learn every time.
Got confused and thought it was tonight 1:00am
Well, at least I can watch it via the link
Great presentation Ray! Really enjoyed it!
Mike
Thank you Raymond for taking the time to organize this presentation. I was unaware of the EVE protocols.
Regarding the question posed by @"Ken Gracey" about what types of peripherals/displays people are using:
TLDR: "SPI or I2C based OLED displays with integrated display controllers". Read further for details.
My current designs are based on some of the small OLED panels of various sizes which support 2 or 4 wire interfaces.
I want to reserve as much of the processing power of the P2 for signal processing (It is available canvas for audio algorithms), so using hub ram or LUT for coordinating HID data is unsavory.
I'll instead be writing "direct mode" drawing routines for the tiny OLED panels which feed pixel commands directly out, rather than buffering images locally.
Because the controllers coupled to these tiny OLED screens come with their own display RAM, I only have to worry about state changes, so juggling user output can be "light touch" on resources.
Now, if I had an option to just plug one of these in with a nice little library for font rendering, line drawing etc, I'd probably do that rather than write it myself so I could focus more on the core of my projects.
My selection of low-memory display solutions may be unusual in that I'm avoiding taking advantage of one of the big benefits of having 8+ cogs.
(You don't have to generally worry about not having enough real-time cores for any given application.)
So what's the big deal about dedicated VRAM?
Because I'm looking at the P2 as a user-programmable DSP for audio/music applications in this case, I'm intentionally stepping lightly around resource usage.
This is so that more advanced algorithms can be run, or algorithms can be run with higher resolution, more layers of real-time+parallel processing, or with more sample space, for example.
Adding larger displays would mean stealing some of this away from the sound, as well as adding higher current requirements, which I don't want to do.
I plan on dedicating 1 COG to "OS" level concerns, and keeping 6 fully free for audio processing. The other is there for that inevitable thing that I forgot I'll need it for.
Just some context, hope this helps sort out the accessory plans!
Matrix Orbital has a few: https://www.matrixorbital.com/display-technology/oled
EVE2 also opens up larger displays over SPI...
One thing I think most drivers have wrong is the exactly VSYNC timing being slightly off due to streamer latency.
But, I don't think that's it...
We do play fast and loose with sync polarity though. Most monitors don't seem to care, by maybe you found one that does...
dgately
I like the SSD1306 for now. I have a few other types like it, but this is in the sweet spot for size and simplicity for my projects.
It's a fairly common display that can be found at multiple vendors, so easy to replace if needed. (OLED can be wear sensitive depending...)
https://forums.parallax.com/discussion/167918/ssd1306-oled-with-the-parallax-propeller