6.0 KiB
There are essentially three ways to build your NodeMCU firmware: cloud build service, Docker image, dedicated Linux environment (possibly VM).
Tools
Cloud Build Service
NodeMCU "application developers" just need a ready-made firmware. There's a cloud build service with a nice UI and configuration options for them.
Docker Image
Occasional NodeMCU firmware hackers don't need full control over the complete tool chain. They might not want to setup a Linux VM with the build environment. Docker to the rescue. Give Docker NodeMCU build a try.
!!! caution
Take note that you need to clone the repository including Git submodules just as described below for the Linux environment.
Linux Build Environment
NodeMCU firmware developers commit or contribute to the project on GitHub and might want to build their own full fledged build environment with the complete tool chain.
Build environment dependencies, tools and libraries:
Ubuntu:
sudo apt-get install -y gperf python-pip python-dev flex bison build-essential libssl-dev libffi-dev libncurses5-dev libncursesw5-dev libreadline-dev cmake
Setting up the repository
Run the following command for a new checkout from scratch. This will fetch the nodemcu repo, checkout the dev-esp32 branch and finally pull all submodules:
git clone --branch dev-esp32 --recurse-submodules https://github.com/nodemcu/nodemcu-firmware.git nodemcu-firmware-esp32
To install the prerequisites for the ESP32 SDK and NodeMCU components, run:
./install.sh
The make menuconfig command initiates the build process, which will start with the configuration menu to set the build options.
!!! important
GNU make version 4.0 or higher is required for a successful build. Versions 3.8.2 and below will produce an incomplete firmware image.
Updating your clone from upstream needs an additional command to update the submodules as well:
git pull origin dev-esp32
git submodule init #only if repo was cloned w/o submodules init
git submodule update --recursive
Here is a video walk through by John Lauer (ChiliPeppr) of building the firmware in Linux from scratch with a fresh install of Ubuntu 19 so you can see all of the dependencies needed to get your build completed and flashed to your ESP32 device.
Build Options
All configuration options are accessed from the file sdkconfig. It's advisable to set it up with the interactive make menuconfig - on a fresh checkout you're prompted to run through it by default.
The most notable options are described in the following sections.
Select Modules
Follow the menu path
Component config --->
NodeMCU modules --->
Tick or untick modules as required.
UART default bit rate
Follow the menu path
Component config --->
Platform config --->
UART console default bit rate --->
CPU Frequency
Follow the menu path
Component config --->
ESP32-specific --->
CPU frequency --->
Stack Size
If you experience random crashes then increase the stack size and feed back your observation on the project's issues list.
Follow the menu path
Component config --->
ESP32-specific --->
Main task stack size --->
Flashing Options
Default settings for flashing the firmware with esptool.py are also configured with menuconfig:
Serial flasher config --->
Default serial port
Default baud rate
Flash SPI mode --->
Detect flash size when flashing bootloader --->
Partition Table
IDF's default partition table Single factory app, no OTA does not provide enough room for a firmware including large modules like e.g. http or sodium. To enable full feature sets, NodeMCU uses a custom partition table from components/platform/partitions.csv which allocates ~1.5 MB for the firmware image. During first boot, the firmware creates an additional partition for SPIFFS in the remaining flash space.
For 2MB flash modules an alternative partition table available as components/platform/partitions-2MB.csv. It restricts the SPIFFS partition to ~448 kB and can be used with menuconfig:
Partition Table --->
Partition Table (Custom partition table CSV)
(components/platform/partitions-2MB.csv) Custom partition CSV file
(0x10000) Factory app partition offset
Using external components
It is possible, and relatively easy, to include external components and modules in NodeMCU. It is not uncommon to have one or more custom modules one wishes to include in the firmware. To enable this NodeMCU leverages the standard IDF EXTRA_COMPONENT_DIRS functionality. As such, it is possible to not only add extra Lua C modules, but also other components such as libraries.
To include one (or more) additional IDF components, simply set the EXTRA_COMPONENT_DIRS environment variable to the space-separated list of directories of said components. E.g.
export EXTRA_COMPONENT_DIRS="/path/to/mymod /path/to/mylib"
make menuconfig
make
To get started, a template directory structure is provided in extcomp-template/ which provides a skeleton for a simple Lua C module, including the build logic in CMakeLists.txt, the configuration option in Kconfig and the Lua C module code in mymod.c. A detailed discussion on the specifics is beyond this document, but the first two are described comprehensively in the official IDF documentation, and module development is covered in Programming in NodeMCU.
In fact, to quickly try it out it's even possible to include the template itself, as-is:
export EXTRA_COMPONENT_DIRS="$PWD/extcomp-template"
make menuconfig
make
after which the command mymod.hello() is available in the Lua environment.