Octoprint-TFT with 3.5 inch touchscreen - 3.5inch RPi LCD 320x480 XTP2046 install and configure for Octopi 3D printer by icXu

 Spent hours figuring out how to configure a 3.5" touchscreen to work with Octoprint-TFT, for my new 3D printer. I have found it very difficult to find any centralised data, therefore I have put all the necessary steps below;

• Download the latest OctoPrint version (actual version: 2019-09-26-octopi-buster-lite-0.17.0.img):

https://octoprint.org/download/

• Download the BalenaEtcher:

https://www.balena.io/etcher/

•  SSH and telnet client - PuTTY:

https://www.putty.org/

• Test editor Notepad++ :

https://notepad-plus-plus.org/downloads/

• Flash the Octoprint image (the downloaded.img file), using the BalenaEtcher, on the SD card

• Open the new flashed card and edit the octopi-wpa-supplicant.txt , introduce your WIFi credentials, and make sure that you uncomment the text by removing #.

Note: do not use WordPad or TextEdit, as it may change the document format, use Notepad++, Atom or VSCode instead.

uncommented:

• Insert the SD card and power up the raspberry pi.

• Log into your Pi via SSH (it is located at octopi.local), the default username is “pi”, the default password is “raspberry”. 

Please see the OctoPi’s readme webpage https://github.com/guysoft/OctoPi#how-to-use-it

• Run the following commands, one by one, in order to update the os: 

sudo apt-get update

sudo apt update

sudo apt dist-upgrade

Press y then enter:  

sudo apt clean

sudo reboot

At this point, we have a fully working Octopi without screen functionality, which can be accessed from the browser at http://octopi.local/

• After reboot open the configuration tool:

 and navigate to System Options - Boot / Auto Login- and select Console Auto Login

sudo raspi-config

Note: 
While you are here you can enable the camera (user Interface section) if you planning to use one.

• LCD drivers installation:

Download the files using the below command: 

git clone  https://github.com/waveshare/LCD-show.git 

Then install them: 

cd LCD-show/

sudo chmod +x LCD35-show

sudo ./LCD35-show

Press y then wait to finish the install- it will reboot and the screen should be functional

At this point, the display should be up and running.

•  Following the display setup, we need to install the UI (user interface), paste the below commands one by one:

sudo apt-get install libgtk-3-0

sudo apt install xserver-xorg xinit xserver-xorg-video-fbdev

wget  https://github.com/mcuadros/OctoPrint-TFT/releases/download/v0.1.2/octoprint-tft_0.1.2-1.stretch_armhf.deb 

sudo dpkg -i octoprint-tft_0.1.2-1.stretch_armhf.deb

sudo systemctl set-default graphical.target

sudo mv /usr/share/X11/xorg.conf.d/99-fbturbo.conf /usr/share/X11/xorg.conf.d/99-fbturbo.conf.old

Now the TFT should be live! However, we need to reboot it: 

sudo reboot

• Using your PC browser navigate to http://octopi.local/ and run the setup wizard:

• Finish the setup then update the OctoPrint

Make sure that the power supply is suitable for your model, otherwise will not run the update.

• After the update is completed navigate to the plugins and enable the virtual printer, itis will help you to test the screen without connecting it to the printer: 

Then click connect:

Now the Octoprint-TFT interface should be accessible and the setup can be safely tested: 

Screen issues: 

• The display can be rotated using the below command:

cd LCD-Show

sudo ./LCD35-show 270

sudo reboot

• If still displays incorrectly we can open the configuration file:

sudo nano /boot/config.txt

and paste the following line: 

dtoverlay=waveshare35a:rotate=270

• 3D printed case (needs alteration)

https://www.thingiverse.com/thing:1422963

• Screen manufacturer website:

https://www.waveshare.com/product/3.5inch-RPi-LCD-A.htm

Hope this helps, 

icXu.