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FBTFT and Device Tree

I’ve remounted my TFT touch display and connected it to another Raspberry Pi. During the installation process I realized, that the FBTFT Kernel is now Device Tree enabled, this makes the installation and configuration process a lot easier. (https://github.com/notro/fbtft/wiki#install)

Therefore you only need to install the FBTFT enabled Firmware (https://github.com/notro/rpi-firmware) and after that you can enable the TFT display HY-28B:

Add the following statement to /boot/config.txt to enable the hy28b overlay:

dtoverlay=hy28b, rotate=90

The overlays can be found on https://github.com/notro/rpi-firmware/tree/master/overlays.

To enable the console output on the display you had to add the following to the first line of /boot/cmdline.txt:

fbcon=map:10 fbcon=font:VGA8X8

After a reboot the display should be recognized and working. You can check it in dmesg.

To use the display with pygame you need to install the following packages and calibrate the touchpanel:

apt-get update
apt-get install libts-bin evtest xinput python-dev python-pip
pip install evdev
sudo TSLIB_FBDEVICE=/dev/fb1 TSLIB_TSDEVICE=/dev/input/event0 ts_calibrate

Update 1:
With the integration of the FBTFT drivers in the Raspberry Pi kernel (https://github.com/notro/fbtft/wiki) it is no longer neccessary to install notro’s FBTFT kernel.

Update 2:
I run in some problems with the display showing no content. The backlight was on but there were no image visible. I was able to fix the problem by setting the GPIO configuration fixed and not automatically:

dtoverlay=hy28b, rotate=90, resetgpio=25, ledgpio=18

Raspberry Pi 2.8″ display

I connected a HYB28B 2.8″ display to my Raspberry Pi to show the current values of my TinyTX sensors. The display is using a pin distance of 2.00mm so I had to used adapter Jumper cables to connect the display to to standard 2.54mm Pins.

The display can show a weather forecast analouge to http://ph-elec.com/archives/rpi-small-lcd-display/ and http://www.exma2004.de/phpBB/viewtopic.php?f=16&t=1843 based on weather data from openweatherdata. Additonally there is a screen to control a MPD instance like http://home.uktechreviews.com/Raspberry/Pi%20blog/files/RaspberryRadio.html.

Wiring

  HY28B   | Raspberry Pi
 ---------|----------------------------
 3V3_IN   | 3V3             pin#1
 GND      | GND             pin#14
 LCDB_SCK | SPI_SCLK GPIO11 pin#23
 LCDB_SDO | SPI_MISO GPIO9  pin#21
 LCDB_SDI | SPI_MOSI GPIO10 pin#19
 LCDB_CS  | SPI_CE0  GPIO8  pin#24
 LCDB_RST |          GPIO25 pin#22
 ---------|-----------------------------
 TP_SCK   | SPI_SCLK GPIO11 pin#23
 TP_SDO   | SPI_MISO GPIO9  pin#21
 TP_SDI   | SPI_MOSI GPIO10 pin#19
 TP_CS    | SPI_CE1  GPIO7  pin#26
 TP_IRQ   |          GPIO17 pin#11
 BL_CTRL  |          GPIO18 pin#12