pi2qvga

USING THOSE CHEAP 2.2 INCH DISPLAYS ON THE PI

CHEAP GRAPHIC OUTPUT FOR THE PI ZERO

OVERVIEW

The prices of 2.2 inch TFT panels have dropped to under four dollars. That means I need to do another Pi Zero project!

These displays were originally meant to interface with an Arduino, but they also work on the Pi. With a little modification to the screen, a Pi Zero sticks on the back and makes a nice compact package.

BUYING ONE

I got mine online at Aliexpress. There are many other vendors, such as Banggood and e-bay.

BUILDING IT

I removed the SD card socket to make the assembly slimmer. I've found the following technique works well: un-solder and remove the metal shell, cut the socket pins just above where they're soldered to the circuit board, then bend the socket up. The connections will break, even if they weren't cut all the way through.

You also need to remove the header pins. It's easiest to remove the plastic strip, then heat the pins with a soldering iron and remove them one by one. If you have trouble removing the plastic, melt it between the pins with a soldering iron.

The Zero can then be attached to the back with double-sided foam tape. The tape must be thick enough to clear the components on the back of the display. Then wire it up - 30 gauge wire wrap wire works well.

WIRING

SOFTWARE SETUP

Use a newer Raspbian iamge, 2016-5-27 or later.

Add dtoverlay=pitft22  to the /boot/config.txt file. It should be on a new line.

Add fbcon=map:10 to the /boot/cmdline.txt file. It should be at the end of the first (and only) line.

Change /dev/fb0 to /dev/fb1 in the /usr/share/X11/xorg.conf.d/99-fbturbo.conf file.

Add vcgencmd display_power 0 to the /etc/rc.local file. It should be on a new line, near the top.

Reboot, and you should see boot-up messages after about 20 seconds. Log in and enjoy!

BACKLIGHT

For a little more brightness, connect GPIO 5 to GPIO 6. For even more, connect GPIO 4 to the other two.

This site has been tested to display correctly using Gnome Web on the Raspberry Pi.