Files
esp-idf/examples
Xiao Xufeng 789ce684c9 fix(mmap): fixed some API read wrong data via mmap when flash being erased/written while XIP on PSRAM
Before:

The cache won't be disabled when XIP on psram. But during flash
erasing/programming, read data will be courrupt.

When XIP in psram is enabled, the image is not mapped to the cache so
usually there will be no flash access. The only way to read from flash
is via the driver or use mmap. The driver has protection during erasing,
while th mmap region not.

Now:

Mmap APIs provide a flag to make mmap->unmap region mutually exclusive
to flash erase/programming when XIP from psram. SPI Flash write APIs
will benefit from this. When the flag is used, no concurrent access to
mapped region will happen while writing; otherwise the cache will be
disable to avoid data corruption.

Most ESP-IDF APIs calls mmap with this flag. As for users calling
mmap-like APIs directly, they can choose whether to enable this by a
flag.

Closes https://github.com/espressif/esp-idf/issues/14897
2026-06-16 01:00:43 +08:00
..
2026-06-15 11:34:48 +08:00

Examples

This directory contains a range of example ESP-IDF projects. These examples are intended to demonstrate parts of the ESP-IDF functionality, and to provide code that you can copy and adapt into your own projects.

Example Layout

The examples are grouped into subdirectories by category. Each category directory contains one or more example projects:

  • bluetooth/bluedroid Classic BT, BLE and coex examples using default Bluedroid host stack.
  • bluetooth/nimble BLE examples using NimBLE host stack.
  • bluetooth/esp_ble_mesh ESP BLE Mesh examples.
  • bluetooth/hci HCI transport (VHCI and HCI UART) examples.
  • build_system Examples of build system features.
  • cxx C++ language utilization examples and experimental components.
  • ethernet Ethernet network examples.
  • get-started Simple examples with minimal functionality. Good start point for beginners.
  • ieee802154 IEEE802.15.4 examples.
  • mesh Wi-Fi Mesh examples.
  • network Examples related to general network environment, test & analysis.
  • openthread OpenThread examples.
  • peripherals Examples showing driver functionality for the various onboard ESP32 peripherals.
  • protocols Examples showing network protocol interactions.
  • security Examples about security features.
  • storage Examples showing data storage methods using SPI flash, external storage like the SD/MMC interface and flash partitioning.
  • system Demonstrates some internal chip features, or debugging & development tools.
  • wifi Advanced Wi-Fi features (For network protocol examples, see protocols instead.)
  • Zigbee Zigbee network and device examples.

In addition to these examples, commmon_components directory contains code shared by several examples.

Using Examples

Before building an example, follow the ESP-IDF Getting Started to ensure you have the required development environment.

Set Chip Target

First of all, your target must be supported by both:

  • By your ESP-IDF version: For the full list of supported targets, run:
    idf.py --list-targets
    
  • By this example: For the full list of supported targets, refer to the supported targets table at the top of this README.

After you make sure that your target is supported, go to your example project directory and set the chip target:

idf.py set-target <target>

For example, to set esp32 as the chip target, run:

idf.py set-target esp32

Configure the Project

For information about Kconfig options, see Project Configuration.

To conveniently check or modify Kconfig options for this example in a project configuration menu, run:

idf.py menuconfig

Build and Flash

Execute the following command to build the project, flash it to your development board, and run the monitor tool to view the serial output:

idf.py build flash monitor

This command can be reduced to idf.py flash monitor.

If the above command fails, check the log on the serial monitor which usually provides information on the possible cause of the issue.

To exit the serial monitor, use Ctrl + ].

Running Test Python Script (pytest)

Some of the examples have pytest_....py scripts that are using the pytest as the test framework. For detailed information, please refer to the "Run the Tests Locally" Section under ESP-IDF tests in Pytest documentation

Using pytest is the recommended way to write new tests. We will migrate all the example test scripts to this new framework soon.

Copying Examples

Each example is a standalone project. The examples do not have to be inside the esp-idf directory. You can copy an example directory to anywhere on your computer in order to make a copy that you can modify and work with.

The IDF_PATH environment variable is the only thing that connects the example to the rest of ESP-IDF.

If you're looking for a more bare-bones project to start from, try esp-idf-template.

Further Development

For further steps on how to develop a project, see the following:

Contributing Examples

If you have a new example you think we'd like, please consider sending it to us as a Pull Request.

In the ESP-IDF documentation, you can find a "Creating Examples" page which lays out the steps to creating a top quality example.