147 lines
5.1 KiB
ReStructuredText
147 lines
5.1 KiB
ReStructuredText
==========
|
||
NuttX RTOS
|
||
==========
|
||
|
||
What is NuttX?
|
||
--------------
|
||
|
||
`NuttX <https://nuttx.apache.org/>`__ is a mature and secure real-time
|
||
operating system (RTOS) with an emphasis on technical standards
|
||
compliance and small size. It is scalable from 8-bit to 64-bit
|
||
microcontrollers and microprocessors and compliant with the Portable
|
||
Operating System Interface (POSIX) and the American National Standards
|
||
Institute (ANSI) standards and with many Linux-like subsystems. The best
|
||
way to think about NuttX is to think of it as a small Unix/Linux for
|
||
microcontrollers.
|
||
|
||
Highlights of NuttX
|
||
~~~~~~~~~~~~~~~~~~~
|
||
|
||
- **Small** - Fits and runs in microcontrollers as small as 32 kB Flash
|
||
and 8 kB of RAM.
|
||
- **Compliant** - Strives to be as compatible as possible with POSIX
|
||
and Linux.
|
||
- **Versatile** - Supports many architectures (ARM, ARM Thumb, AVR,
|
||
MIPS, OpenRISC, RISC-V 32-bit and 64-bit, RX65N, x86-64, Xtensa,
|
||
Z80/Z180, etc.).
|
||
- **Modular** - Its modular design allows developers to select only
|
||
what really matters and use modules to include new features.
|
||
- **Popular** - NuttX is used by many companies around the world.
|
||
Probably you already used a product with NuttX without knowing it was
|
||
running NuttX.
|
||
- **Predictable** - NuttX is a preemptible Realtime kernel, so you can
|
||
use it to create predictable applications for realtime control.
|
||
|
||
--------------
|
||
|
||
Why NuttX + LVGL?
|
||
-----------------
|
||
|
||
Although NuttX has its own graphic library called
|
||
`NX <https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=139629474>`__,
|
||
LVGL is a good alternative because users could find more eye-candy demos
|
||
and they can reuse code from previous projects. LVGL is an
|
||
`Object-Oriented Component
|
||
Based <https://blog.lvgl.io/2018-12-13/extend-lvgl-objects>`__
|
||
high-level GUI library, that could fit very well for a RTOS with
|
||
advanced features like NuttX. LVGL is implemented in C and its APIs are
|
||
in C.
|
||
|
||
Here are some advantages of using LVGL in NuttX
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
- Develop GUI in Linux first and when it is done just compile it for
|
||
NuttX. Nothing more, no wasting of time.
|
||
- Usually, GUI development for low level RTOS requires multiple
|
||
iterations to get things right, where each iteration consists of
|
||
**``Change code`` > ``Build`` > ``Flash`` > ``Run``**. Using LVGL,
|
||
Linux and NuttX you can reduce this process and just test everything
|
||
on your computer and when it is done, compile it on NuttX and that is
|
||
it.
|
||
|
||
NuttX + LVGL could be used for
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
- GUI demos to demonstrate your board graphics capacities.
|
||
- Fast prototyping GUI for MVP (Minimum Viable Product) presentation.
|
||
- visualize sensor data directly and easily on the board without using
|
||
a computer.
|
||
- Final products with a GUI without a touchscreen (i.e. 3D Printer
|
||
Interface using Rotary Encoder to Input data).
|
||
- Final products with a touchscreen (and all sorts of bells and
|
||
whistles).
|
||
|
||
--------------
|
||
|
||
How to get started with NuttX and LVGL?
|
||
---------------------------------------
|
||
|
||
There are many boards in the `NuttX
|
||
mainline <https://github.com/apache/incubator-nuttx>`__ with support for
|
||
LVGL. Let’s use the
|
||
`STM32F429IDISCOVERY <https://www.st.com/en/evaluation-tools/32f429idiscovery.html>`__
|
||
as an example because it is a very popular board.
|
||
|
||
First you need to install the pre-requisites on your system
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
Let’s use the `Windows Subsystem for
|
||
Linux <https://acassis.wordpress.com/2018/01/10/how-to-build-nuttx-on-windows-10/>`__
|
||
|
||
.. code:: shell
|
||
|
||
$ sudo apt-get install automake bison build-essential flex gcc-arm-none-eabi gperf git libncurses5-dev libtool libusb-dev libusb-1.0.0-dev pkg-config kconfig-frontends openocd
|
||
|
||
Now let’s create a workspace to save our files
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
.. code:: shell
|
||
|
||
$ mkdir ~/nuttxspace
|
||
$ cd ~/nuttxspace
|
||
|
||
Clone the NuttX and Apps repositories:
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
.. code:: shell
|
||
|
||
$ git clone https://github.com/apache/incubator-nuttx nuttx
|
||
$ git clone https://github.com/apache/incubator-nuttx-apps apps
|
||
|
||
Configure NuttX to use the stm32f429i-disco board and the LVGL Demo
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
.. code:: shell
|
||
|
||
$ ./tools/configure.sh stm32f429i-disco:lvgl
|
||
$ make
|
||
|
||
If everything went fine you should have now the file ``nuttx.bin`` to
|
||
flash on your board:
|
||
|
||
.. code:: shell
|
||
|
||
$ ls -l nuttx.bin
|
||
-rwxrwxr-x 1 alan alan 287144 Jun 27 09:26 nuttx.bin
|
||
|
||
Flashing the firmware in the board using OpenOCD:
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
.. code:: shell
|
||
|
||
$ sudo openocd -f interface/stlink-v2.cfg -f target/stm32f4x.cfg -c init -c "reset halt" -c "flash write_image erase nuttx.bin 0x08000000"
|
||
|
||
Reset the board and using the ‘NSH>’ terminal start the LVGL demo:
|
||
|
||
.. code:: shell
|
||
|
||
nsh> lvgldemo
|
||
|
||
Where can I find more information?
|
||
----------------------------------
|
||
|
||
- This blog post: `LVGL on
|
||
LPCXpresso54628 <https://acassis.wordpress.com/2018/07/19/running-nuttx-on-lpcxpresso54628-om13098/>`__
|
||
- NuttX mailing list: `Apache NuttX Mailing
|
||
List <http://nuttx.incubator.apache.org/community/>`__
|