Table of Contents
This blog post demonstrates how to get a LVGL sample up and running on the nRF9160 DK using Adafruit 1.3" 240x240 Wide Angle TFT LCD Display with MicroSD - ST7789. Follow the wiring guide and the steps in the blog post and get your display going! In an ideal world, we would be able to use the st7789v shield for waveshare 240x240, but since the nRF9160 DK does not have a device tree node label for
arduino_spi, we need to implement a workaround. For the details on how the project configuration and overlay files were derived, check out my other blog post.
- nRF9160 DK
- 1.3" 240x240 TFT LCD Display using a ST7789V driver
- 8 jumper wires
Important: The display operates with 3.3V logic, so on the nRF9160 DK, you must ensure that a tiny switch, SW9 (which sets VDD IO) is set at 3V!
Following the generic ST7789V shield pin assignment, we wire the connection as such:
|nRF9160 DK pin||Display pin|
After having wired up your DK, we need to perform some steps on the software side!
This SDK uses LVGL v7.6.1 so this project might not be compatible with builds that were released after Feb 24th (which is when LVGL was updated in Zephyr)
- Download the attached project
- Extract it into a valid west workspace (that is, a folder from which you can call the command
west buildfrom command line)
- Connect your nRF9160 DK (with the screen already wired up) to your computer
- Build and flash the project to the DK
Incorporating this into other projects
If you want this display to work with your project (let's call it
YourProject), you need to:
- Ensure that the LVGL and display-specific settings from the provided ZIP's config file (
prj.conf) is in
YourProject's config file
- Ensure that the overlay from the provided ZIP is also included (that is,
YourProjectalready has an overlay file (
nrf9160dk_nrf9160ns.overlay), you could copy-paste the contents of the provided overlay file to
YourProjectdoes not have an overlay file, then you could copy the whole file into
YourProjectfolder. This will automatically be detected by CMake when you hit build!
- Be sure to include
lvgl.hin the C-file in which you want to program using LVGL.
Note on the source code structure
The source code might not look like ordinary LVGL code (which uses
lv_init, lv_disp_draw_buf_init etc) because this part of LVGL is abstracted away by Zephyr, as seen in lvgl.c in Zephyr. The source code is also based on the LVGL sample provided by Zephyr, with changes made so that it works with the nRF9160 DK when following this tutorial.