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Adafruit 2.8" PiTFT - Capacitive Touch Created by lady ada https://learn.adafruit.com/adafruit-2-8-pitft-capacitive-touch Last updated on 2022-06-22 12:36:46 PM EDT ©Adafruit Industries Page 1 of 48 Table of Contents Overview 5 Assembly 8 Easy Install 9 • • • • • • • • • • • • • • • 9 10 11 13 14 14 15 16 16 18 18 18 18 19 19 Install Raspberry Pi OS on an SD Card Installer script Easy Single Command Install Options Interactive Installation Configuring what shows where PiTFT as Text Console (best for Raspberry Pi OS 'Lite') PiTFT as HDMI Mirror (Best for Raspberry Pi OS with Desktop) PiTFT as Raw Framebuffer Device Creating Your Own Automated Command Uninstalling The Driver Unsupported Full Images PiTFT 2.2" Images PiTFT 2.4"/2.8"/3.2" Resistive Images PiTFT 2.8" Capacitive PiTFT 3.5" Images Capacitive Touchscreen Configuration 19 • • • • • • • 20 21 21 22 23 23 24 If you are running EP0110M09 driver If you are running FT6236 driver If you are running FT6X06 driver Event Testing AutoMagic Calibration Script TSLIB calibration X11 Calibration Console Configuration • Turn off Console Blanking • Raspbian Jessie • Raspbian Wheezy Playing Videos • How To Play Videos • Converting/Resizing Videos 24 27 27 27 28 28 30 Displaying Images 32 Using FBCP 34 Backlight Control 35 Extras! 36 • Making it easier to click icons in X • Right-click on a touchscreen Gesture Input • Installation ©Adafruit Industries 36 37 38 38 Page 2 of 48 • Usage 39 PiTFT PyGame Tips 41 • Install pip & pygame • Ensure you are running SDL 1.2 • Using the Capacitive touch screen in PyGame 41 42 44 F.A.Q. 44 Downloads 45 • • • • • Files Schematic for Pi 1 Version Schematic for PiTFT Plus (B+/Pi 2 shape) Fabrication Print (Pi 1 Version) Fabrication Print (B+/Pi 2 Version) ©Adafruit Industries 45 45 46 46 47 Page 3 of 48 ©Adafruit Industries Page 4 of 48 Overview Our best-selling PiTFT just got a fancy upgrade, now we have a version with a capaciti ve touchscreen! That's right, instead of a resistive touchscreen, which requires a fingernail or stylus, you can now use a fingerpad. The screen looks much nicer, with a black bezel and glass overlay. Featuring a 2.8" display with 320x240 16-bit color pixels and a capacitive touch overlay. The plate uses the high speed SPI interface on the Pi and can use the mini display as a console, X window port, displaying images or video etc. Best of all it plugs right in on top! ©Adafruit Industries Page 5 of 48 Uses the hardware I2C Pins (SDA & SCL), SPI pins (SCK, MOSI, MISO, CE0) as well as GPIO #25 and #24. All other GPIO are unused. Since we had a tiny bit of space, there's 4 spots for optional slim tactile switches wired to four GPIOs, that you can use if you want to make a basic user interface. For example, you can use one as a power on/off button. See below for the link to get the optional tact switches, they're not included. The screen is the same size as the resistive type so you can use this with the PiTFT PiBow or any other enclosure you may already have. We also use the same SDL device and signals so PyGame and X11 based programs can be swapped in with no changes in code. ©Adafruit Industries Page 6 of 48 It's designed to fit nicely onto the Pi Model A or B rev 2 but also works perfectly fine with the Model B+ as long as you don't mind the PCB overhangs the USB ports by 5mm, see the photos above. Model B rev 1 have an older layout for the I2C pins and won't be able to use the touch screen This version comes as a mini-kit, with a 2x13 extra-tall female header (to connect the plate to the Pi) and a 2x13 male header that can be used to connect an IDC cable or cobbler from the side. The photos above also show the optional installed slim tactile buttons. The tactile buttons are not included, but you can pick up a pack of 20 here. ( http://adafru.it/1489) Some basic soldering is required to install the headers. You can also pick up an extra-long Pi stacking header if you want to install that instead of the 2x13 female header installed. (http://adafru.it/1112) ©Adafruit Industries Page 7 of 48 Assembly We are now selling these displays pre-assembled - skip this step if your PiTFT is not a mini-kit This section is identical to the PiTFT Resistive 2.8" so please visit that page to complete assembly of this Pi Plate ©Adafruit Industries Page 8 of 48 Visit the 2.8" Resistive PiTFT Assembly Page https://adafru.it/dDQ Easy Install The PiTFT requires some device tree support and a couple other things to make it a nice stand-alone display. If you just want to get going, check out the following for easy-install instructions! The same installer is used for all PiTFTs, you will pick and configure the setup during installation! Install Raspberry Pi OS on an SD Card You'll need to start with Raspberry Pi OS or Raspberry Pi OS Lite. The last known for-sure tested-and-working version is May 28, 2021 (https:// downloads.raspberrypi.org/raspios_lite_armhf/images/ raspios_lite_armhf-2021-05-28/ (https://adafru.it/VGE)) from https:// downloads.raspberrypi.org/raspios_lite_armhf/images/ (https://adafru.it/VHb) ©Adafruit Industries Page 9 of 48 Raspberry Pi OS does often 'break' stuff when new versions come out so to be safe, if you are having problems try this version! The latest Raspberry Pi Bullseye release is new and may have issues with the PiTFT. In that case, you can try the previous buster release. Installer script This script will do all the work for you, and install both device tree overlay support as well as configure rotation and any HDMI mirroring. PiTFT no longer needs any custom kernels or modules, so you can continue to update/upgrade your Pi and it will work with the most recent releases. Here's the commands to run. Make sure your Pi has network access, it needs to download the software! The latest installer script was rewritten in Python, so it can be installed with just a few commands. First, start by installing a few dependencies and downloading the repo: cd ~ sudo apt-get update sudo apt-get install -y git python3-pip sudo pip3 install --upgrade adafruit-python-shell click git clone https://github.com/adafruit/Raspberry-Pi-Installer-Scripts.git cd Raspberry-Pi-Installer-Scripts ©Adafruit Industries Page 10 of 48 Easy Single Command Install Options The latest script allows you to specify all of your options within the command so you can sit back and watch the installation. We'll cover interactive installation below if you want to answer each prompt for a customized installation. “Console Mode” Install Commands If you just want a Linux text console to appear on the display, use one of the following commands: For the PiTFT 2.4", 2.8", or 3.2" Resistive touchscreens, use the following command: sudo python3 adafruit-pitft.py --display=28r --rotation=90 --install-type=console For the PiTFT 2.8" Capacitive touchscreen, use the following command: sudo python3 adafruit-pitft.py --display=28c --rotation=90 --install-type=console For the PiTFT 2.2" Display, use the following command: sudo python3 adafruit-pitft.py --display=22 --rotation=90 --install-type=console For the PiTFT 3.5" Resistive touchscreen, use the following command: sudo python3 adafruit-pitft.py --display=35r --rotation=90 --install-type=console For the Mini PiTFT 1.3", BrainCraft HAT, 1.3" Color TFT Bonnet, or 1.5" Display, use the following command: sudo python3 adafruit-pitft.py --display=st7789_240x240 --rotation=0 --installtype=console For the Mini PiTFT 1.14" Display, use the following command: sudo python3 adafruit-pitft.py --display=st7789_240x135 --rotation=270 --installtype=console ©Adafruit Industries Page 11 of 48 FBCP Install Commands If you want to mirror the HDMI output to the display, known as “FrameBuffer Copy” or FBCP for short, use one of the following commands: For the PiTFT 2.4", 2.8", or 3.2" Resistive touchscreens, use the following command: sudo python3 adafruit-pitft.py --display=28r --rotation=90 --install-type=fbcp For the PiTFT 2.8" Capacitive touchscreen, use the following command: sudo python3 adafruit-pitft.py --display=28c --rotation=90 --install-type=fbcp For the PiTFT 2.2" Display, use the following command: sudo python3 adafruit-pitft.py --display=22 --rotation=90 --install-type=fbcp For the PiTFT 3.5" Resistive touchscreen, use the following command: sudo python3 adafruit-pitft.py --display=35r --rotation=90 --install-type=fbcp For the Mini PiTFT 1.3", BrainCraft HAT, 1.3" Color TFT Bonnet, or 1.5" Display, use the following command: sudo python3 adafruit-pitft.py --display=st7789_240x240 --rotation=0 --installtype=fbcp For the Mini PiTFT 1.14" Display, use the following command: sudo python3 adafruit-pitft.py --display=st7789_240x135 --rotation=270 --installtype=fbcp Rebooting When it asks you to reboot, then choose yes because the setting won't take full effect until you do so. ©Adafruit Industries Page 12 of 48 Interactive Installation For an interactive install, you can just run the script without any options: sudo python3 adafruit-pitft.py Once you run it you will be presented with menus for configuration. Display Selection Start by selecting the board that best corresponds with your PiTFT. There's lots of options and we will likely be adding more in the future. Rotation Next you will be asked for the rotation you want, don't worry if you're not 100% sure which you want, you can always change this later by re-running the script ©Adafruit Industries Page 13 of 48 It will take a few minutes to install the software and download all the things... Configuring what shows where You have a few different ways to set up the PiTFT, we ask 2 questions to figure out what you want PiTFT as Text Console (best for Raspberry Pi OS 'Lite') This is the simplest to set-up type of use. Its great if you have a simple text based or pygame/SDL based interface. If you want the PiTFT to act as a text console you can expect: • HDMI will be 'deactivated' - nothing appears on the HDMI output but a black screen • The login prompt appears on the Pi • The Pi is all text, not a GUI (no PIXEL desktop) • Keyboard and mouse are used only by the PiTFT interface • Framebuffer-capable software (such as fbi for displaying images, mplayer for videos, or pygame software, etc) appear on the PiTFT • OpenGL accelerated software will not appear on the PiTFT (it is unaccelerated framebuffer only) • But, non-OpenGL-accelerated graphics software is a bit faster than using HDMI mirroring (not tons faster but you're not running fbcp which will always make it faster) ©Adafruit Industries Page 14 of 48 If you want that, say Yes to the question Would you like the console to appear on the PiTFT display Then simply reboot. Once rebooted you will not see anything on HDMI, but the console will appear on the PiTFT. That's it! PiTFT as HDMI Mirror (Best for Raspberry Pi OS with Desktop) This option is the easiest to understand: whatever appears on the HDMI display will be 'mirrored' to the PiTFT. Note that HDMI is much higher resolution so it's not like it turns the PiTFT into a 1080p display. This is great for when you want to run OpenGLoptimized software, PIXEL desktop software, or really anything. The down-side is its a little slower than drawing directly to the framebuffer. You may not notice it but it's worth us mentioning! • HDMI will be 'activated' but at a lower resolution - you can change this later but it looks best at 320x240 (PiTFT 2.2", 2.4", 2.8" and 3.2") or 480x320 (PiTFT 3.5") • The login prompt or GUI appears on both HDMI and PiTFT at the same time • Keyboard and mouse are shared, since the display is mirrored • All graphics appear on both HDMI and PiTFT, thanks to fbcp If you want that, say Yes to the question Would you like the HDMI display to mirror to the PiTFT display? ©Adafruit Industries Page 15 of 48 PiTFT as Raw Framebuffer Device For advanced users who are comfortable using framebuffer devices, it is possible to have the PiTFT and HDMI graphics be both active and display different data. • HDMI will be active and act like a normal Pi • The login prompt or GUI (PIXEL) appears on the HDMI • PiTFT appears black, nothing appears on it • Keyboard and mouse are used by the HDMI interface but can, in theory, be captured and used to change graphics on PiTFT through programming • Framebuffer-capable software (such as fbi for displaying images, mplayer for videos, or pygame software, etc) can appear on the PiTFT if you set it up to display to /dev/fb1 • OpenGL accelerated software will never appear on the PiTFT (it is unaccelerated framebuffer only) If you want that, say No to both of the configuration questions! You can always change your mind after setting up one of the configurations, depending on your needs! Just re-run the script Creating Your Own Automated Command Under the Easy Single Command Install Options section, there are a bunch of different installation flags that you can choose between. If you want to create your own command, you can find the latest options by typing: sudo python3 adafruit-pitft.py --help ©Adafruit Industries Page 16 of 48 The main options to pay attention to are the --display , --rotation , and -install-type arguments. For the display, you can either choose the number you type for the options or the display type, which has the options listed under help. For instance, to us the 2.8" Resisitive display you could use --display=1 or --display=28r For the rotation, you can either choose the number you type for the options or the angle, which has the options also listed under help. To use 90 degrees, you could use --rotation=1 or --rotation=90 For install type, You can either choose fbcp, console or uninstall. To use FBCP, you would simply supply --install-type=fbcp Automated Reboot Option To go with a fully automated installation, you can provide a --reboot flag. To always reboot, use: --reboot=yes This is useful if you want to use the display right after running the script. To never reboot immediately, use --reboot=no This is useful if you want it as part of a larger script that installs many things. Custom User Directory By default, it is installed under the current user directory, but you can provide the -u or --user flag along with the folder that you want to install to. ©Adafruit Industries Page 17 of 48 Uninstalling The Driver To uninstall, you would either run the script interactively and choose Uninstall or you can provide the uninstall flag: --install-type=uninstall Unsupported Full Images Historically, we provided full 'images' of Raspbian, which is now called Raspberry Pi OS. This worked OK until Raspbian started doing releases every few months. These are no longer supported, and won't even boot on Pi 3B+, so we recommend the script above. There's the larger 'classic Jessie' image that will boot into X by default, and requires a 8G image, it has a lot more software installed. There's also the smaller 'Jessie Lite' that will boot into the command line, and can be burned onto a 2G card! Click below to download and install into a new SD card. Unzip and follow the classic SD card burning tutorials  (https://adafru.it/aMW) PiTFT 2.2" Images • Raspbian Jessie 2016/10/23-based image (https://adafru.it/sbg) • Raspbian Jessie Lite 2016/10/23-based image (https://adafru.it/sbh) • Raspbian Jessie 2016/03/25-based image (https://adafru.it/mAe) • Raspbian Jessie Lite 2016/03/25-based image (https://adafru.it/mAf) • Raspbian Jessie 2015/09/24-based image (https://adafru.it/iDC) • Raspbian Wheezy 2015/09/09-based image (https://adafru.it/idt) PiTFT 2.4"/2.8"/3.2" Resistive Images • Raspbian Jessie 2016/9/23-based image (https://adafru.it/s7f) • Raspbian Jessie Lite 2016/9/23-based image (https://adafru.it/s7A) • Raspbian Jessie 2016/03/25-based image (https://adafru.it/mA9) • Raspbian Jessie Lite 2016/03/25-based image (https://adafru.it/mAa) • Raspbian Jessie 2015/09/24-based image (https://adafru.it/iDA) • Raspbian Wheezy 2015/09/09-based image (https://adafru.it/idJ) • Raspbian 2014/06/20-based image (https://adafru.it/dSM) • Raspbian 2014/09/09-based image (https://adafru.it/e12) ©Adafruit Industries Page 18 of 48 PiTFT 2.8" Capacitive • Raspbian Jessie 2016-09-23-based image (https://adafru.it/saM) • Raspbian Jessie Lite 2016-09-23-based image (https://adafru.it/saN) • Raspbian Jessie 2016-03-25-based image (https://adafru.it/mAc) • Raspbian Jessie Lite 2016-03-25-based image (https://adafru.it/mAd) • Raspbian Jessie 2015/09/24-based image (https://adafru.it/iDy) • Raspbian Wheezy 2015/09/24-based image (https://adafru.it/idz) • Raspbian 2014/09/18-based image (https://adafru.it/e11) • Raspbian 2014/06/20-based image (https://adafru.it/dSO) • Raspbian image from 2015/03/03 (https://adafru.it/eUI) PiTFT 3.5" Images • Raspbian Jessie 2016/9/23-based image (https://adafru.it/siF) • Raspbian Jessie Lite 2016/9/23-based image (https://adafru.it/sja) • Raspbian Jessie 2016/03/25-based image (https://adafru.it/mAb) • Raspbian Jessie 2016/03/25-based image (https://adafru.it/mAG) • Raspbian Jessie 2015/09/24-based image (https://adafru.it/iDD) • Raspbian Wheezy 2015/09/24-based image (https://adafru.it/idy) • Raspbian 2014/09/09-based image (https://adafru.it/e10) • Raspbian 2015/03/12 image (https://adafru.it/eUE) Capacitive Touchscreen Configuration If you've grabbed our Easy Install image, or use the script, this step is not required, it's already done! This is just for advanced users who are curious on how to configure and customize the touchscreen The capacitive touch driver in Raspbian no longer works with "ts_test" because it doesn't emit 'proper' touchscreen events. It works in LXDE though. ©Adafruit Industries Page 19 of 48 The nifty thing about capacitive touch screens is that they do not require calibration! The calibration is done 'in chip' on the screen itself. However, we still do need to tell the Pi how to read the capacitive chip. Before we start, we'll make a udev rule for the touchscreen. That's because the event X name of the device will change a lot and its annoying to figure out what its called depending on whether you have a keyboard or other mouse installed. First up figure out if you have the FT62X6 driver or FT6236 driver by running dmesg | grep ft6 or dmesg | grep EP0110M09   If you are running EP0110M09 driver Run sudo nano /etc/udev/rules.d/95-ftcaptouch.rules to create a new udev file and copy & paste the following line in: SUBSYSTEM=="input", ATTRS{name}=="EP0110M09", ENV{DEVNAME} =="*event*", SYMLINK+="input/touchscreen" ©Adafruit Industries Page 20 of 48 If you are running FT6236 driver Run sudo nano /etc/udev/rules.d/95-ft6236.rules to create a new udev file and copy & paste the following line in: SUBSYSTEM=="input", ATTRS{name}=="ft6236", ENV{DEVNAME} =="*event*", SYMLINK+="input/touchscreen" If you are running FT6X06 driver Run sudo nano /etc/udev/rules.d/95-ft6206.rules to create a new udev file and copy & paste the following line in: SUBSYSTEM=="input", ATTRS{name}=="ft6x06_ts", ENV{DEVNAME} =="*event*", SYMLINK+="input/touchscreen" Reboot the Pi with sudo reboot Then type ls -l /dev/input/touchscreen It should point to eventX where X is some number, that number will be different on different setups since other keyboards/mice/USB devices will take up an event slot ©Adafruit Industries Page 21 of 48  (https://adafru.it/dIX) Event Testing Even though capacitive touch screens don't require calibration, there are some useful tools we can use to debug the touchscreen. Install the "event test" and "touchscreen library" packages with sudo apt-get install evtest tslib libts-bin Now you can use some tools such as sudo evtest /dev/input/touchscreen which will let you see touchscreen events in real time, press on the touchscreen to see the reports. ©Adafruit Industries Page 22 of 48 AutoMagic Calibration Script If you rotate the display you need to recalibrate the touchscreen to work with the new screen orientation. You can manually run the calibration processes in the next section, or you can re-run the installer script and select a new rotation: Try using this default calibration script to easily calibrate your touchscreen display. Note that the calibration values might not be exactly right for your display, but they should be close enough for most needs. If you need the most accurate touchscreen calibration, follow the steps in the next section to manually calibrate the touchscreen. TSLIB calibration In order to use TSLIB - basically, the touchscreen without X11 - you'll need to set the calibration for TSLIB in /etc/pointercal With a resistive touchscreen, you have to calibrate it. Since capacitive touchscreens don't require calibration you can just input the numbers directly. Run sudo nano /etc/pointercal And enter in the following values (there's a single space between each number) and hit return afterwards. Then save 320 65536 0 -65536 0 15728640 65536 ©Adafruit Industries Page 23 of 48 Next you can run sudo TSLIB_FBDEVICE=/dev/fb1 TSLIB_TSDEVICE=/dev/input/touchscreen ts_test X11 Calibration X11 uses a different calibration system than TSLib/PyGame. You can see how to run xtcal here (https://adafru.it/BFX) except use EP0110M09 as the name of the device Console Configuration If you've used our installer script, this step is not required, it's already done! This is just for advanced users who are curious on how to configure and customize the console ©Adafruit Industries Page 24 of 48 One fun thing you can do with the display is have it as your main console instead of the HDMI/TV output. Even though it is small, with a good font you can get 20 x 40 of text. For more details, check out https://github.com/notro/fbtft/wiki/Boot-console (http s://adafru.it/cXQ) First up, we'll update the boot configuration file to use the TFT framebuffer /dev/fb1 instead of the HDMI/TV framebuffer /dev/fb0 sudo nano /boot/cmdline.txt you can also edit it by putting the SD card into a computer and opening the same file. At the end of the line, find the text that says rootwait and right after that, enter in: fbcon=map:10 fbcon=font:VGA8x8 then save the file. On the next boot, it will bring up the console. Note that the kernel has to load up the display driver module before it can display anything on it so you won't get the rainbow screen, a NooBs prompt, or a big chunk of the kernel details since the module is loaded fairly late in the boot process. I think the VGA8x8 font is a bit chunky, you probably want 12x6 which is what is shown in the photo above. To change the font, run sudo dpkg-reconfigure consolesetup and go thru to select Terminus 6x12 ©Adafruit Industries Page 25 of 48 ©Adafruit Industries Page 26 of 48 Turn off Console Blanking You may notice the console goes black after 30 minutes, this is a sort of 'power saving' or 'screensaver' feature. Raspbian Jessie  Add the following line to /etc/rc.local sudo sh -c "TERM=linux setterm -blank 0 >/dev/tty0" on the line before the final exit 0 Raspbian Wheezy You can disable this by editing /etc/kbd/config and looking for  BLANK_TIME=30 and setting the blank time to 0 (which turns it off) BLANK_TIME=0 ©Adafruit Industries Page 27 of 48 Playing Videos How To Play Videos You can play many types of videos on the screen, using mplayer you don't even need to run X and you can script the movies to play using Python. We'll show you how to just play one video for now. To demo, we'll use an mp4 of Big Buck Bunny for 320 pixel wide screens. Below we ©Adafruit Industries Page 28 of 48 show you how to create/resize videos, but to make it easy, just download our version with: wget http://adafruit-download.s3.amazonaws.com/ bigbuckbunny320p.mp4 (https://adafru.it/cXR) The video is 30MB which is a lot if you haven't expanded your SD card yet. Before you do this, run sudo raspi-config to expand the SD card so you don't run out of space! If you don't have mplayer yet, run sudo apt-get update sudo apt-get install mplayer to install it. It may take a few minutes to complete OK now you just have to run: sudo SDL_VIDEODRIVER=fbcon SDL_FBDEV=/dev/fb1 mplayer -vo sdl framedrop bigbuckbunny320p.mp4 If your video is not sized for 320 wide, you may need to add a -zoom after framedrop so that it will resize - note that this is quite taxing for the Pi, so it may result in a choppy or mis-synced video! ©Adafruit Industries Page 29 of 48 Converting/Resizing Videos It's possible to play full length videos on the TFT plate, but since the screen is small and the Pi cant use hardware accelleration to play the videos its best to scale them down to 320x240 pixels. This will be easier for the Pi to play and also save you tons of storage space. For this demo, we'll be using the famous Big Buck Bunny (https:// adafru.it/cXS) video, which is creative commons and also very funny! You can download it from the link above, we'll be using the 720p AVI version. ©Adafruit Industries Page 30 of 48 To do the conversion itself, we suggest HandBrake (https://adafru.it/cXT) which works great and is open source so it runs on all operating systems! Download and install from the link. Then run the installed application and open up the AVI file from before. The app will pre-fill a bunch of information about it. Under Destination click Browse... to select a new MP4 file to save. Then under Picture change the Width to 320 (the height will be auto-calculated) Click START to begin the conversion, it will take a minute or two. ©Adafruit Industries Page 31 of 48 That's it! You now have a smaller file. Don't forget to play it on your computer to make sure it plays right before copying it to your Pi Displaying Images You can display every day images such as GIFs, JPGs, BMPs, etc on the screen. To do this we'll install fbi which is the frame buffer image viewer (not to be confused with the FBI agency!) sudo apt-get install fbi will install it ©Adafruit Industries Page 32 of 48 Grab our lovely wallpapers with wget http://adafruit-download.s3.amazonaws.com/ adapiluv320x240.jpg wget http://adafruit-download.s3.amazonaws.com/ adapiluv480x320.png (https://adafru.it/cXU) For 320x240 PiTFTs (2.2", 2.4", 2.8" or 3.2") view it with sudo fbi -T 2 -d /dev/fb1 -noverbose -a adapiluv320x240.jpg or for 3.5" PiTFTs: sudo fbi -T 2 -d /dev/fb1 -noverbose -a adapiluv480x320 (htt ps://adafru.it/cXU).png That's it! ©Adafruit Industries Page 33 of 48 Using FBCP The Ideal: Adafruit’s PiTFT displays are razor sharp. Whereas small composite screens on the Raspberry Pi usually require some video scaling (resulting in blurriness), PiTFT uses the GPIO header, digitally controlled pixel-by-pixel for a rock steady image. Though not a lot of pixels, it works great for retro gaming (and the display neatly stacks above the board, no side protuberances for video cables). The Downside: this GPIO link entirely bypasses the Pi’s video hardware, including the graphics accelerator. Many games and emulators depend on the GPU for performance gains. So the PiTFT has traditionally been limited to just a subset of specially-compiled emulators that can work and run well enough without the GPU. ©Adafruit Industries Page 34 of 48 The Solution: our latest PiTFT drivers, along with a tool called fbcp (framebuffer copy), careful system configuration, and (optionally) the more potent Raspberry Pi 2 board open the doors to many more gaming options. Existing emulator packages (such as RetroPie, with dozens of high-performance emulators and ports) — previously offlimits to the PiTFT — can run quite effectively now! Click here to go to our FBCP tutorial! https://adafru.it/fbe Backlight Control Unlike the resistive PiTFT, the capacitive version does not have a resistive touch controller chip that we can take advantage of as an extra backlight control pin. Instead, you can set up GPIO #18 as an on/off or PWM control. Note that if you are playing audio out the headphone jack, you can't use the PWM capabilities of GPIO #18 at the same time, the PWM function is reassigned to do audio. However,  you can use it as a simple on/off pin To enable using GPIO #18 as a backlight, solder closed the #18 backlight jumper on the PiTFT capacitive PCB! OK now you can use the PWM output on GPIO 18. There's python code available for controlling the PWM pin but you can also just use the WiringPi shell commands. ©Adafruit Industries Page 35 of 48 With these basic shell commands, you can set the GPIO #18 pin to PWM mode, set the output to 100 (out of 1023, so dim!), set the output to 1000 (out of 1023, nearly all the way on) and 0 (off) gpio gpio gpio gpio -g -g -g -g mode 18 pwm pwm 18 100 pwm 18 1000 pwm 18 0 Try other numbers, from 0 (off) to 1023 (all the way on)! Extras! Making it easier to click icons in X If you want to double-click on icons to launch something in X you may find it annoying to get it to work right. In LXDE you can simply set it up so that you only need to single click instead of double. From LXDE launch the file manager (sorry these pix are grayscale, still figuring out how to screenshot the framebuffer!) Then under the Edit menu, select Preferences ©Adafruit Industries Page 36 of 48 Then select Open files with single click and close the window (you'll need to drag it over to get to the X button Right-click on a touchscreen Obviously if you have a touchscreen, it cannot tell what finger you are pressing with. This means that all 'clicks' are left clicks. But if you want a right-click, you can do it. Just add the following lines into your InputClass of /etc/X11/xorg.conf.d/99calibration.conf after the calibration section Option "EmulateThirdButton" "1" Option "EmulateThirdButtonTimeout" "750" Option "EmulateThirdButtonMoveThreshold" "30" So for example your file will look like: ©Adafruit Industries Page 37 of 48 Section "InputClass"    Identifier      "calibration"    MatchProduct    "stmpe-ts"    Option  "Calibration"   "3800 120 200 3900"    Option  "SwapAxes"      "1"    Option "EmulateThirdButton" "1"    Option "EmulateThirdButtonTimeout" "750"    Option "EmulateThirdButtonMoveThreshold" "30" EndSection This makes a right mouse click emulated when holding down the stylus for 750 ms. (Thx adamaddin! (https://adafru.it/fH3)) Gesture Input With the PiTFT touchscreen and xstroke (https://adafru.it/dD0) you can enter text in applications by drawing simple character gestures on the screen! Check out the video below for a short demonstration and overview of gesture input with xstroke: Installation Unfortunately xstroke hasn't been actively maintained for a few years so there isn't a binary package you can directly install. However compiling the tool is straightforward and easy with the steps below. Credit for these installation steps goes to mwilliams03 at ozzmaker.com (https://adafru.it/dD1). First install a few dependencies by opening a command window on the Pi and executing: sudo apt-get -y install build-essential libxft-dev libxpm-dev libxtst-dev Now download, compile, and install xstroke by executing: cd ~ wget http://mirror.egtvedt.no/avr32linux.org/twiki/pub/Main/XStroke/ xstroke-0.6.tar.gz tar xfv xstroke-0.6.tar.gz cd xstroke-0.6 ./configure sed -i '/^X_LIBS = / s/$/ -lXrender -lX11 -lXext -ldl/' Makefile make sudo make install ©Adafruit Industries Page 38 of 48 If the commands above execute successfully xstroke should be installed. If you see an error message, carefully check the dependencies above were installed and try again. Once xstroke is installed you will want to add a couple menu shortcuts to start and stop xstroke. Execute the following commands to install these shortcuts: wget https://github.com/adafruit/PiTFT_Extras/raw/master/xstroke.desktop wget https://github.com/adafruit/PiTFT_Extras/raw/master/xstrokekill.desktop sudo cp xstroke*.desktop /usr/share/applications/ Usage To use xstroke I highly recommend using a plastic stylus instead of your finger. Also c alibrate the touchscreen for X-Windows (https://adafru.it/dD2) so you have the best control over the cursor possible. Don't use a ballpoint pen or sharp metal stylus as it could scratch or damage the touchscreen! Start X-Windows on the PiTFT and open the LXDE menu by clicking the icon in the lower left corner. Scroll up to the Accessories menu at the top and notice the new XSt roke and XStroke Kill commands. Click the XStroke menu option to start xstroke. You should see a small pencil icon appear on the bottom right side of the screen. The pencil icon means xstroke is running, however by default it's not yet looking for gesture input. Open an application that takes text input, such as LXTerminal. To enable gesture input click the xstroke pencil icon. You should see the pencil turn green and the text 'abc' written over top of the icon. You might need to click the icon a few times to get the click to register in the right spot. When xstroke is looking for gesture input you can drag the mouse cursor in a gesture anywhere on the screen to send specific key strokes. Here's a picture of the possible gestures you can send: ©Adafruit Industries Page 39 of 48 (credit to Carl Worth for the image above) To draw a gesture from the above image, press anywhere on the screen, start from the circle in the gesture, and follow the gesture pattern towards the arrow. As you draw a gesture you should see a blue line displayed that shows what you've drawn. Lift up the stylus when you get to the end of the gesture at the arrow. If xstroke recognizes the gesture it will send the appropriate key press to the active window. Try drawing a few characters from the image above to get the hang of writing gestures. A few very useful gestures are backspace (which deletes a character), return/enter, and space. To draw a backspace gesture just draw a line going from the right side of the screen to the left side. The gesture for return/enter is a diagonal line from the top right to bottom left. Finally a space is a straight line from the left to the right. Note that when xstroke is looking for gestures you might not be able to click or control the cursor as you normally would expect. To stop xstroke's gesture recognition carefully press the xstroke pencil icon again until the 'abc' text disappears. I've found this process can be a little finicky as the icon is very small and any movement will be interpreted as a gesture. Use a light touch and try a few times to click the icon. If you get stuck completely and can't disable xstroke by clicking the icon, connect to the Raspberry Pi in a terminal/SSH connection and run 'killall xstroke' (without quotes) to force xstroke to quit. The normal way to stop xstroke is to navigate to the Accessori es -> XStroke Kill command, but you might not be able to do that if xstroke is listening for gesture input. ©Adafruit Industries Page 40 of 48 Have fun using xstroke to control your Pi by writing gestures on the PiTFT screen! PiTFT PyGame Tips Since the PiTFT screen is fairly small, you may need to write custom UI programs. Pygame is the easiest way by far to do this. Jeremy Blythe has an excellent tutorial here on getting started. (https://adafru.it/saw)  However, before you follow that link you'll want to set up pygame for the best compatibility: Install pip & pygame Install Pip: sudo apt-get install python-pip Install Pygame: sudo apt-get install python-pygame (this will take a while) ©Adafruit Industries Page 41 of 48 Ensure you are running SDL 1.2 SDL 2.x and SDL 1.2.15-10 have some serious incompatibilities with touchscreen. You can force SDL 1.2 by running a script. (Thanks to heine in the forums! (https://adafru.it/ sax)) Edit a new file with sudo nano installsdl.sh and paste in the following text: #!/bin/bash # enable wheezy package sources echo "deb http://legacy.raspbian.org/raspbian wheezy main " > /etc/apt/sources.list.d/wheezy.list # set stable as default package source (currently buster) echo "APT::Default-release \"stable\"; " > /etc/apt/apt.conf.d/10defaultRelease # set the priority for libsdl from wheezy higher then the buster package echo "Package: libsdl1.2debian Pin: release n=buster Pin-Priority: -10 Package: libsdl1.2debian Pin: release n=wheezy Pin-Priority: 900 " > /etc/apt/preferences.d/libsdl # install apt-get update apt-get -y --allow-downgrades install libsdl1.2debian/wheezy run sudo sh ./installsdl.sh ©Adafruit Industries Page 42 of 48 it will force install SDL 1.2 OK now you can continue with pygame ©Adafruit Industries Page 43 of 48 Using the Capacitive touch screen in PyGame The 2.8" Capacitive touch screen driver may not work by default in pygame, but this handy script shows how you can capture the device messages in python to create a UI • https://github.com/nift4/pigame (https://adafru.it/CYv) For examples: https://github.com/nift4/Raspberry-Pi-Testing (https://adafru.it/CYA) F.A.Q. The display works, but the capacitive touch part doesnt Check that you installed the right image, there's one for resistive and one for capacitive PiTFT's If that doesn't help, you can verify your RasPi model number with the command cat /proc/cpuinfo, if it's revision # 0002 or 0003 that means it's a rev 1 Model B, (https://adafru.it/dXg) and will not work due to the I2C pins changing. Does this screen do multi-touch? Nope! This capacitive touch screen is single-touch only. Hey...I was looking at the FT6206 datasheet and it looks like it can support multitouch (two points)! The chip does in fact support multitouch, but the screen layout itself is singletouch. We'll keep looking for a low cost multitouch screen, but we found that at the small size of this screen, single-touch is pretty good! Also, very few linux programs support MT. How do I automatically boot to X windows on the PiTFT? Check out the 2.8" resistive PiTFT FAQ (https://adafru.it/dJ2) for an answer to this common question. ©Adafruit Industries Page 44 of 48 I have some more questions! Check out the 2.8" Resistive PiTFT FAQ page for some other questions you may want answered Visit the 2.8" Resistive PiTFT FAQ page https://adafru.it/dJ2 Downloads Files • The latest kernel fork that adds all the TFT, touchscreen, and other addons is here on github (https://adafru.it/aPa) • Datasheet for the 'raw' 2.8" TFT display (https://adafru.it/sEt) • FT6206 Datasheet (https://adafru.it/sEu) & App note (https://adafru.it/dRn) (capacitive chip) • EagleCAD PCB files on GitHub (https://adafru.it/oYC) Schematic for Pi 1 Version ©Adafruit Industries Page 45 of 48 Schematic for PiTFT Plus (B+/Pi 2 shape) Fabrication Print (Pi 1 Version) Dimensions in Inches ©Adafruit Industries Page 46 of 48 Fabrication Print (B+/Pi 2 Version) Dimensions in mm ©Adafruit Industries Page 47 of 48 ©Adafruit Industries Page 48 of 48