OVMS3-idf/docs/get-started/make-project.rst

Build and Flash with Make
=========================


Finding a project
-----------------

As well as the `esp-idf-template <https://github.com/espressif/esp-idf-template>`_ project, ESP-IDF comes with some example projects on github in the :idf:`examples` directory.

Once you've found the project you want to work with, change to its directory and you can configure and build it.


Configuring your project
------------------------

::

    make menuconfig


Compiling your project
----------------------

::

    make all

... will compile app, bootloader and generate a partition table based on the config.


Flashing your project
---------------------

When ``make all`` finishes, it will print a command line to use esptool.py to flash the chip. However you can also do this from make by running::

    make flash

This will flash the entire project (app, bootloader and partition table) to a new chip. The settings for serial port flashing can be configured with `make menuconfig`.

You don't need to run ``make all`` before running ``make flash``, ``make flash`` will automatically rebuild anything which needs it.


Compiling & Flashing Just the App
---------------------------------

After the initial flash, you may just want to build and flash just your app, not the bootloader and partition table:

* ``make app`` - build just the app.
* ``make app-flash`` - flash just the app.

``make app-flash`` will automatically rebuild the app if it needs it.

There's no downside to reflashing the bootloader and partition table each time, if they haven't changed.


The Partition Table
-------------------

Once you've compiled your project, the "build" directory will contain a binary file with a name like "my_app.bin". This is an ESP32 image binary that can be loaded by the bootloader.

A single ESP32's flash can contain multiple apps, as well as many kinds of data (calibration data, filesystems, parameter storage, etc). For this reason, a partition table is flashed to offset 0x8000 in the flash.

Each entry in the partition table has a name (label), type (app, data, or something else), subtype and the offset in flash where the partition is loaded.

The simplest way to use the partition table is to `make menuconfig` and choose one of the simple predefined partition tables:

* "Single factory app, no OTA"
* "Factory app, two OTA definitions"

In both cases the factory app is flashed at offset 0x10000. If you `make partition_table` then it will print a summary of the partition table.

For more details about :doc:`partition tables <../api-guides/partition-tables>` and how to create custom variations, view the :doc:`documentation <../api-guides/partition-tables>`.