Perfect tiny display for rpi3

[Axy]

I'm looking for a tiny (smaller than 4 inches) display for my rpi3.
I already have a tft hat, but since it works with framebuffers, no easy way of hw accel.

I do not want to deal with framebuffers, I want the dispaly to work plug and play. I beleive this is much easier as a solution, no dealing with drivers, everything is perfect.

However, the smallest screen I could find (that works with hdmi) is 5 inches. I couldn't find any smaller than that.
Is hdmi what I'm looking for? If so, is there a reason there is no hdmi screen smaller than 5 inches?

What are my options at this point?

[hansotten]

Composite is always an option.

[PiGraham]

I'm looking for a tiny (smaller than 4 inches) display for my rpi3.
I already have a tft hat, but since it works with framebuffers, no easy way of hw accel.

I do not want to deal with framebuffers, I want the dispaly to work plug and play. I beleive this is much easier as a solution, no dealing with drivers, everything is perfect.

However, the smallest screen I could find (that works with hdmi) is 5 inches. I couldn't find any smaller than that.
Is hdmi what I'm looking for? If so, is there a reason there is no hdmi screen smaller than 5 inches?

What are my options at this point?

You can have hardware acceleration with an SPI connected TFT by using DMA copy of a GPU surface to SPI. See fbcp. Video decode can be done by the GPU. Scaling to TFT size done by GPU. Expect ~12 fps.

If you want faster then composite video is probably the best bet. See 3.5" reversing camera screen.

[Axy]

Thank you for the replies.
12 fps would not be enough, I'm looking for 60 fps.

Reversing camera displays look nice, but is there any display made specifically for rpi, like a hat, or something along the lines?

[PiGraham]

Thank you for the replies.
12 fps would not be enough, I'm looking for 60 fps.

Reversing camera displays look nice, but is there any display made specifically for rpi, like a hat, or something along the lines?

Reversing displays don't look nice, but they do work. The low resolution combined with dot crawl on composite doesn't look nice. The official DSI 7" screen is vastly better. SPI TFT screens look a lot better than composites of the same size.
Bear in mind that composite is interlaced, so moving images can show interlace artefacts on the image (coarse comb patterns on moving edges).

What do you want to display on this screen?

[Axy]

Oh I see, I'm familiar with internaced footage, that wouldn't do the work.
I wanted to use the display for experimental GUI based projects, so the main purpose is displaying visuals.

I'm aware of the quality of the official 7 inch display, bt for my purposes, it's too big. I want something much more compact, that's why I stated "smaller than 5 inches"

[SkyRise]

Have a look at Adafruit

https://www.adafruit.com/product/1601

There are others, just have a nose around...

[Axy]

These are regular TFTs, they work with framebuffers and they're not plug and play (you need to install drivers and/or make modification to the kernel).

They can't make use of the hw acceleration (with tweaks they can, partly) like hdmi does.

[DirkS]

These are regular TFTs, they work with framebuffers and they're not plug and play (you need to install drivers and/or make modification to the kernel).

They can't make use of the hw acceleration (with tweaks they can, partly) like hdmi does.

FTFY
But you are right. HDMI is probably the only choice. I have never seen very small HDMI devices, though

[Axy]

hm wondering why you overlned the aprts about kernels and drivers -
is there any plug and play choice?

[DirkS]

hm wondering why you overlned the aprts about kernels and drivers -
is there any plug and play choice?

Not plug and play, but a lot of the TFT displays (including these from Adafruit) only need configuration. No need to install any drivers and messing about with the kernel.

[PiGraham]

It may be possible to connect a small LCD to A Pi with a parallel interface. Gert VGA666 used such an interface configuration to implement a passive DAC VGA output. I saw a post here recently from someone who had adapted Gert's design to drive an LCD.

That will be a fast output from the GPU. Not plug and play, but no kernel re compile required AFAIK.

Maybe it would work with a screen like this:
http://www.buydisplay.com/default/lcd-3 ... kout-board

You may be limited to resolutions supported by the Video Core. Is there a mode as low as 320 x 480?

[DougieLawson]

Composite is always an option.

No it isn't, because it's ugly enough on a full size TV.

viewtopic.php?t=79120 is the OP's best option.

[hansotten]

Composite is always an option.

No it isn't, because it's ugly enough on a full size TV.

viewtopic.php?t=79120 is the OP's best option.

The OP specifically specified: no framebuffers, no drivers, so the TinyLCD is not his best option. And if I would suggest a fb solution: an Adafruit PiTFT, because their support is much better.

Composite indeed is ugly, but bearable on these tiny screens.

[PiGraham]

This article may be relevant.

http://blog.reasonablycorrect.com/raw-dpi-raspberry-pi/

Pros:
•Very fast, easily driving our display at 60hz.
•No complicated interface hardware.
•Pixel perfect output. Digital, not analog.
•Easy to understand protocol.
•No bulky connectors.
•Very inexpensive.

Cons:
•Eats a lot of GPIO pins (All of them at true color, but more on this later.)
•Not widely adopted on the Raspberry Pi, making online help hard to find.
•Ribbon cables are easy to break if you’re not careful.
•Short range. If you want your screen 10 meters from the Pi use HDMI.
•There will be maths, this isn’t plug-n-play.
•Almost zero official documentation.

See also:

https://learn.adafruit.com/adafruit-dpi ... ah-ttl-tft