A higher end ILI9341?

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iambrentiam

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Hi Everyone -

The ILI9341 is pretty cool for its price point but it is missing a few features that could make it a lot better. First is obviously the lack of double buffering when using RGB565 can cause flicker when rendering. The second is the interface could really use a command to write multiple pixels of the same color to consecutive memory locations to reduce communication overhead. I have done some googling around for a display with these features but have not found anything. Can anyone recommend a higher end version of the ILI9341 that addresses these issues?

Thanks!
Brent
 
I'm not aware of any similar (inexpensive) display with double buffering. But I hope one comes along, 'cause that's be awesome and we all be able to do really amazing things with it.

There's a not-so-cheap display used by Gameduino2. I don't know the specs, but it might have some of this stuff. Maybe worth a look?
 
Thanks Paul - The Gameduino2 does look very interesting for doing interactive UI with charts and stuff.
 
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First post!

I've done some diving into this before, though I don't have direct experience with these.

The displays like the one in the Gameduino2 (similar to the one in the old PSP) are really simple. They need to be constantly clocked with raw pixel data (think 9 MHz RGB888, Hsync, Vsync, and porches) to work properly, and the LED backlight needs a constant-current driver at ~15-24V. There may be just enough GPIOs on a Teensy 3.x to directly drive the interface, but that's probably all you'd be doing with it, if it works at all. There are a few FPGA implementations out there, as well as driver ICs.

As far as easy and maker-friendly options, there's:
  • Gameduino2 ($70, Adafruit)
    FPGA-based driver, RGB888 output (16M colors)​
    JPEG decoding​
    audio decoding​
    sprite engine​
    antialiased circles and lines​
    built-in gradient, text, and button rendering​
  • 4D Systems uLCD43 ($145, Sparkfun)
    SSD1963-based driver, RGB565 output (65k colors)​
    basically a whole programmable unit with a desktop-based UI designer and on-board GPIO​
  • Bare panel and driver board ($65 total, Adafruit)
    Equivalent panel of the above (4.3" 480x272 with touchscreen)​
    RA8875-based driver board, SPI interface, RGB888 output (16M colors)​
    Adafruit provides an Arduino library to talk to this chip, based on the Adafriut_GFX library​
  • Other retailers (price varies)
    Often cheaper​
    Often pre-assembled LCD+PCB​
    May come directly from China​

The RA8875 can support a single buffer up to 800x480 (and Adafruit carries 5" and 7" displays at this resolution), or you can maintain two whole 480x272 buffers (called "layers" in the datasheet) and flip transparency between them. It also does alpha blending and overlays using the two layers, pattern fills, text, filled/empty geometric shapes, and other graphics stuff, if that's your thing. Though there probably isn't any antialiasing on the built-in stuff.

SSD1963 drivers seem to do roughly the same job as the RA8875, but lack the built-in drawing and overlay/double-buffer functionality.

...I hadn't really thought about getting something like this, but I think I'm reconsidering that.
 
The possible options there are no cheap, here for example:
Riverdi FT801 2.8"
That TFT has a ILI9341 as IC powered by FT801 like a GPU

If the cash is not a problem, you can achieve great performance. This is an example with FT800 4.3" (FT843 of 4DSystems) and gameduino 2 shield


The key is the gameduino 2 library created by James Bowman.

This is another example: Riverdi 7" FT813 + Teensy 3.6 SDIO playing back jpgs as video sequence


FT81xmania work in progress
 
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