This example shows how to override the default chip driver list provided by IDF. Please make sure the SPI_FLASH_OVERRIDE_CHIP_DRIVER_LIST config option is enabled when you build this project (though it should already be enabled by default via `sdkconfig.defaults`). See [the programming guide](https://docs.espressif.com/projects/esp-idf/en/stable/api-reference/storage/spi_flash_override_driver.html) for more details regarding this feature.
**CAUTION: This is only an example showing how to extend your own flash chip driver. Espressif doesn't guarantee the chip driver in the example is reliable for mass production, nor the reliability of the flash models that appear in this example. Please refer to the specification of your flash chip, or contact the flash vendor if you have any problems with the flash chip.**
(See the README.md file in the upper level 'examples' directory for more information about examples.)
## How to use example
Follow detailed instructions provided specifically for this example.
Select the instructions depending on Espressif chip installed on your development board:
- [ESP32 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/stable/get-started/index.html)
- [ESP32-S2 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/get-started/index.html)
## Example folder contents
The project **custom_flash_driver** contains one source file in C language [main.c](main/main.c). The file is located in folder [main](main).
The component **custom_chip_driver** placed under **components** folder, provides
ESP-IDF projects are built using CMake. The project build configuration is contained in `CMakeLists.txt` files that provide set of directives and instructions describing the project's source files and targets (executable, library, or both).
Below is short explanation of remaining files in the project folder.
```
├── CMakeLists.txt
├── sdkconfig.defaults Default options to add into sdkconfig file (mainly to enable the SPI_FLASH_OVERRIDE_CHIP_DRIVER_LIST option)
├── example_test.py Python script used for automated example testing
├── main
│ ├── CMakeLists.txt
│ └── main.c
├── components/custom_chip_driver
│ ├── CMakeLists.txt
│ ├── linker.lf Linker script to put the customized chip driver into internal RAM
└── README.md This is the file you are currently reading
```
For more information on structure and contents of ESP-IDF projects, please refer to Section [Build System](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/build-system.html) of the ESP-IDF Programming Guide.
