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Hardware
- 29 Apr, 2017
- 5 min read
Official Raspberry Pi 7" Touch Screen LCD Display assembly guide - install and tips
This tutorial will show you how to assemble your Raspberry Pi Touchscreen, which power supply options are available and a few helpful hints. Required parts:original 7 inch LCD Touchscreen for Raspberry Pi A Raspberry Pi A+,B+, Pi 2, or Pi 3 Micro USB power adapter with a minimum of 2A Micro SD card with the most recent Raspbian, or Noobs versionContentsInstall/connect Raspberry Pi Touchscreen With the new 7 inch version the controller board is already connected to the display. You just need to connect the Raspberry Pi to the controller board.Connect the red jumper cable with the 5V pin and the black cable with GND of the touchscreen's controller board. This ways the Raspberry Pi is supplied with power through the touchscreen. Connect the flat ribbon cable (DSI) with the silverish contacts to the brown side. You can now attach the Raspberry Pi into the controller board and fix it with the screws. Attach now the red jumper cable to the GPIO pin 4 and the black cable to the GPIO pin 6. The flat ribbon cable (DSI) need to be plugged into the connector with the label "Display" (contacts to the inside). Finally you need to plug the micro usb power adapter into the controller board of the touchscreen. The setup may not be supplied with power through the Raspberry Pi as the internal fuse of the Raspberry Pi cannot handle the 400 mA that the touchscreen requires.It is possible to use the touchscreen and another screen (HDMI output) at the same time. Error Sources If the screen stays black after the start check the DSI cable (white flat ribbon cable). THE DSI connects the Raspberry Pi and the controller board of the touchscreen.Shut down the Raspberry Pi and check if the cable is connected in the correct direction. At the Raspberry Pi the silverish contacts need to point to the inside (white side of the connector). At the touch controller board the contacts need to point to the brown side of the connector.Update the operating system. sudo apt-get update && sudo apt-get dist-upgradeWhen downloading, the image can look blurry - that's normal.Alternative Power Supplies There are 3 possibilities to supply the touchscreen and the Raspberry Pi with power.Jumper Cable As described above, connect the +5V and Ground pin of the controller board of the touchscreen with the GPIO pins of the Raspberry Pi. Now the Raspberry Pi is supplied by power through the display. This variant is simple and cheap but it is impossible to attach a extention board.Y Micro USB cable You can use a micro USB Y-cable to supply both micro USB inputs at the same time. This way you can use a extension board at the Raspberry Pi requireing only one power supply.Two Power Supplies Use two micro USB poer supplies, to supply the touchscreen and the Raspberry Pi separately with power. If you use a power demanding extension board it could be required to use two power supplies. In that case the display and the Raspberry Pi need to be turned on at the same time!Rotate Image If you want to use the touchscreen in portrait mode or turned by 180° follow the steps below. I use the case from Pimoroni. For this the images needs to be rotated by 180°.Open the config.txt file with the Nano text editor. sudo nano /boot/config.txtAdd the following text at the beginning of the config.txt. lcd_rotate=2 lcd_rotate=0 Normal lcd_rotate=1 90 Degree lcd_rotate=2 180 Degree lcd_rotate=3 270 Degree lcd_rotate=0x10000 mirror horizontally lcd_rotate=0x20000 mirror verticallyQuite the editing with the shortcut ctrl+ and save the changes with y.The image should be rotated after a restart of the system. sudo rebootSet up Right Click The right click via touch needs to be set up. Two fingers for the "right mouse button" This tutorial describes how you can set up that a two-finger touch executes a right click. Long press of "right mouse button This option does not work with Raspbian Jessie.Open the file xorg.conf with the nano text editor. sudo nano /etc/X11/xorg.conf Section "InputClass" Identifier "calibration" Driver "evdev" MatchProduct "FT5406 memory based driver" Option "EmulateThirdButton" "1" Option "EmulateThirdButtonTimeout" "750" Option "EmulateThirdButtonMoveThreshold" "30" EndSection Close the editor with ctrl-x and confirm the changes with y.Restart the system sudo rebootInstall a On-Screen or Virtual Keyboard You can choose between different on-screen keyboards. I use Florence as the Matchbox keyboard has problems under Jessie and causes a constant CPU usage of 25%.Florence sudo apt-get install florence You can now activate the Florence virtual keyboard under Universal Access. In my case Florence crashed always which could be fixed after installing at-spi2-core. sudo apt-get install at-spi2-coreMatchbox Keyboard sudo apt-get install matchbox-keyboard Active the on-screen keyboard under " MENU > Accessories > Keyboard".Adjust Brightness of Backlight You can adjust the brightness of the backlight with the terminal.If you want to save power you can use the following command to adjust the brightness. sudo sh -c "echo 'Value of Brightness' >> /sys/class/backlight/rpi_backlight/brightness"Replace Value of Brightness with a number between 0 and 255. At 0 the backlight is off and at 255 the brightest value is achieved. Hide mouse poniter As descibed in the tutorial "Midori Browser in Fullscreen Mode" you can install the application unclutter to hide the mouse pointer. sudo apt-get install unclutterUnclutter starts automatically after a system start. The mouse pointer should disappear automatically after 1-2 seconds. Technical DataCompatible with Raspberry Pi A+, B+, 2 & 3 17,8 cm (7") touch display, capacitive Dimensions (LxWxH): 192.96 x 112.76mm Visible Area: 154.08 x 85.92mm Resolution: 800 x 480 Pixel Contrast: 500 Brightness: 250 cd/m2 24 bit Colours 10 Finger multi touch display Bachlight adjustable via PWM Backlight lifetime of 20000 hours Operation temperature: -20°C bis +70°C Storage temperature: -30°C bis +80°C Viewing angle: upper (50), lower (70), right (70), left (70)A technical drawing with detailled dimensions can be found here.
- 22 Apr, 2017
- 1 min read
Enable UART Port on Raspberry Pi
By standard the UART interface is configured as serial console. If you want to use the UART interface for other things, e.g. for a GPS module, the standard function needs to be deactivated. Open the cmdline.txt file with the Nano text editor. sudo nano /boot/cmdline.txt and remove the following part from the file. console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 The content of the file should look like this dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait Exit the editor with ctrl+x and save the changes using y.Open inittab sudo nano /etc/inittab and search for the following line. T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100 Insert a # at the beginning of the line to comment this line. Doing so the line should look like this. #T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100 Exit the editor the same ways as in the previous step.From Kernel 3.18.x on the following step must be excecuted aditionally. sudo nano /boot/config.txt Search for the following line and remove the # at the beginning of the line. #dtparam=spi=on Exit the editor the same ways as in the previous step. Show kernel version uname -aRestart RPI. sudo reboot
- 21 Feb, 2017
- 2 Min. Lesezeit
Raspberry Pi Zero mit USB Buchse Typ-A erweitern (anlöten)
Der Raspberry Pi Zero hat nur einen Micro USB Anschluss. Der zweite Micro USB Anschluss ist für die Stromversorgung. Da der Raspberry Pi Zero keinen internen WIFI Chip hat wie der Raspberry PI 3, benötig man einen USB WIFI Stick, um eine WLAN-Verbindung herstellen zu können. Da es keine Micro USB WIFI Sticks zu kaufen gibt, benötigt man einen Adapter von USB-Typ A auf Micro USB. ODER... man lötet eine USB-Typ A Buchse an den Raspberry Pi Zero an. Dies ist nicht sehr schwer und günstig. Es hat auch den Vorteil, dass du andere USB Geräte direkt anschließen kannst und das die Form des Raspberry Pi Zero klein bleibt. Benötigte Teile: Raspberry Pi Zero (günstig auf Pimoroni) USB Typ-A Buchse (Amazon) 4x Kabel (ca. 4cm je Kabel) Benötigtes Werkzeug: Lötkolben Lötzinn Messer oder Abisolierzange Heißklebepistole oder Kleber (zum befestigen der USB-Buchse am Raspberry Pi Zero)Entferne zwei die zwei überstehenden Punkte mit einem Messer oder Cutter. Löte die Kabel an. Sie sollten min. 4cm lang sein, da sie sonst nicht bis zu den Lötpunkten am Raspberry Pi Zero reichen. Klebe jetzt die USB Type-A Buchse mit der Heißklebepistole auf den Raspberry Pi Zero. Positioniere die Buchse wie auf dem Foto. So passen bei bedarf Mini HDMI Kabel und USB Kabel gleichzeitig an den Raspberry Pi Zero. Verwende ruhig etwas mehr Kleber, damit das Metall die Leiterplatte nicht berührt. Fixiere und Schütze die Kabel mit ein bißchen Heißkleber. Löte die Kabel vom USB Anschluss an den Raspberry Pi Zero an. Der Lötpunkt für Data+ und Data- liegen recht nah beieinander. Achte darauf, dass sie durch das Löten nicht verbunden werden. Fertig! Du kannst den USB Anschluss jetzt zum Beispiel mit einem EDIMAX EW-7811UN WLAN Stick verwenden. Ob man den Micro-USB Anschluss und den zustätzlichen Type-A gleichzeitig verwenden kann, habe ich noch nicht ausprobiert. Schreib deiner Erfahrung unser Forum.
- 21 Nov, 2016
- 1 Min. Lesezeit
Neuer Raspberry Pi 2B 1.2 mit 64-bit BCM2837 Prozessor
Ohne Ankündigung hat der Raspberry Pi 2B ein upgrade erhalten. Die Revision 1.2 des Raspberry Pi 2B wird seit September 2016 mit dem neuen BCM2837 Prozessor hergestellt. Die Rev. 1.2 unterscheidet sich nur vom Prozessor. Der verbaute Prozessor BCM2837 (64-bit ARM Cortex-A53) ist der selbe wie bei einem Raspberry Pi 3. Jedoch ist dieser auf 900 MHz gedrosselt (1200 MHz RPi3). Frühere Versionen hatten ein Broadcom BCM2836 (ARM Cortex-A7) verbaut. Der Preis beträgt ca. $35. Lohnt sich der kauf? Ein schnellerer Raspberry Pi 3 ist fast genau so teuer und hat zusätzlich noch ein Wifi und Bluetooth Modul verbaut. Quelle: RasPi.tv