df4195062d
The implicit promise of heap_alloc_caps() and friends is that the memory it returns is fit for the purpose as requested in the caps field. Before this commit, that did not happen; e.g. DMA-capable memory wass returned from a correct region, but not aligned/sized to something the DMA subsystem can handle. This commit adds an API to the esp_mm component that is then used by the heap component to adjust allocation alignment, caps and size dependent on the hardware requirement of the requested allocation caps. |
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.. | ||
main | ||
CMakeLists.txt | ||
pytest_ram_loadable_app.py | ||
README.md | ||
sdkconfig.ci.defaults | ||
sdkconfig.ci.pure_ram | ||
sdkconfig.defaults |
Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C6 | ESP32-H2 | ESP32-P4 | ESP32-S2 | ESP32-S3 |
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RAM loadable app Example
Starts a FreeRTOS task to print "Hello World". The segments of this application are fully linked and run in internal RAM.
(See the README.md file in the upper level 'examples' directory for more information about examples.)
How to use example
Hardware Required
This example should be able to run on any commonly available ESP32 development board.
Configure the project
idf.py menuconfig
This step is optional, the default settings in sdkconfig.defaults
are already set to enable the ram_loadable app feature.
CONFIG_APP_BUILD_TYPE_RAM
is enable by default so that all programs and data are linked into internal RAM. For more information about CONFIG_APP_BUILD_TYPE_RAM
you can refer to the description in menuconfig.
(Enabling APP_BUILD_TYPE_PURE_RAM_APP
option IDF will not compile the spi_flash
related code into bin, which will save a lot of internal ram space. For esp32
target, limited by its RAM layout, the available RAM space for the app is too small to accommodate this example without this option enabled, so this option is selected by default for esp32 target.)
Build and Load to RAM
Build the project and load it to the chip's internal RAM, then run monitor tool to view serial output:
idf.py set-target {target name}
idf.py build
esptool.py -p PORT --no-stub load_ram build/ram_loadable_app.bin
idf.py -p PORT monitor --no-reset
(Replace PORT with the name of the serial port to use.)
(To exit the serial monitor, type Ctrl-]
.)
(For ram_loadable_app, after the chip is reset, it will start from flash by default, so the program will be executed directly after loading to ram. This is the reason why we use --no-reset
. Besides, manually opening idf.py monitor will lose part of the log at startup because the serial port cannot be opened in time, so it is recommended to use a separate serial converter to monitor the output of the UART TX pin)
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.