zephyr

History

Martí Bolívar 7355204f41 samples: lvgl: add min_ram to adafruit_2_8_tft_touch_v2 test Commit `c79b1a38aa` ("samples: display: Convert driver and lvgl sample.yaml to use depends_on") started using depends_on in the sample YAML for a lvgl application instead of platform_allow. This breaks build testing with twister and overflow checking enabled on more resource constrained platforms. The test case's .config ends up with: CONFIG_LVGL_HOR_RES_MAX=320 CONFIG_LVGL_VER_RES_MAX=240 CONFIG_LVGL_VDB_SIZE=64 CONFIG_LVGL_BITS_PER_PIXEL=24 And lib/gui/lvgl/lvgl.c, where we allocate a buffer of size: (CONFIG_LVGL_BITS_PER_PIXEL * ((CONFIG_LVGL_VDB_SIZE * CONFIG_LVGL_HOR_RES_MAX * CONFIG_LVGL_VER_RES_MAX) / 100) / 8) Require 147456 bytes to build the sample, ultimately overflowing RAM if you run something along the lines of: twister -T samples -p <constrained_platform> --overflow-as-errors This is a reasonable test to be doing to make sure that sample RAM requirements do not get too big for a subset of platforms that are of interest, and it no longer works. To fix it, add a min_ram line for this case so that we can still run overflow tests on a large set of samples without fine-grained special casing or creating an ever-growing list of platform excludes for this test. Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>		2021-08-24 15:40:06 -04:00
..
boards	boards: hsdk: dts: remove ili9340 from hsdk dts	2021-04-28 10:53:52 -04:00
src
CMakeLists.txt	cmake: increase minimal required version to 3.20.0	2021-08-20 09:47:34 +02:00
prj.conf
README.rst	doc: use kconfig role and directive	2021-06-29 10:26:28 -04:00
sample.yaml	samples: lvgl: add min_ram to adafruit_2_8_tft_touch_v2 test	2021-08-24 15:40:06 -04:00

README.rst

.. _lvgl-sample:

LittlevGL Basic Sample
######################

Overview
********

This sample application displays "Hello World" in the center of the screen
and a counter at the bottom which increments every second. If an input driver
is supported, such as the touch panel controller on mimxrt10{50,60,64}_evk
boards, "Hello World" is enclosed in a button that changes to the toggled state
when touched.

Requirements
************

Display shield and a board which provides a configuration
for Arduino connectors, for example:

- :ref:`adafruit_2_8_tft_touch_v2` and :ref:`nrf52840dk_nrf52840`
- :ref:`buydisplay_2_8_tft_touch_arduino` and :ref:`nrf52840dk_nrf52840`
- :ref:`ssd1306_128_shield` and :ref:`frdm_k64f`

or a simulated display environment in a native Posix application:

- :ref:`native_posix`
- `SDL2`_

or

- :ref:`mimxrt1050_evk`
- `RK043FN02H-CT`_

or

- :ref:`mimxrt1060_evk`
- `RK043FN02H-CT`_

Building and Running
********************

.. note::
   When deferred logging is enabled you will likely need to increase
   :kconfig:`CONFIG_LOG_STRDUP_BUF_COUNT` and/or
   :kconfig:`CONFIG_LOG_STRDUP_MAX_STRING` to make sure no messages are lost or
   truncated.

Example building for :ref:`nrf52840dk_nrf52840`:

.. zephyr-app-commands::
   :zephyr-app: samples/display/lvgl
   :board: nrf52840dk_nrf52840
   :shield: adafruit_2_8_tft_touch_v2
   :goals: build flash

Example building for :ref:`native_posix`:

.. zephyr-app-commands::
   :zephyr-app: samples/display/lvgl
   :board: native_posix
   :goals: build flash

References
**********

.. target-notes::

.. _LittlevGL Web Page: https://littlevgl.com/
.. _SDL2: https://www.libsdl.org
.. _RK043FN02H-CT: https://www.nxp.com/products/processors-and-microcontrollers/arm-based-processors-and-mcus/i.mx-applications-processors/i.mx-rt-series/4.3-lcd-panel:RK043FN02H-CT