esp-idf/examples/storage/partition_api/partition_mmap/README.md

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| Supported Targets | ESP32 | ESP32-C3 | ESP32-S2 | ESP32-S3 |
| ----------------- | ----- | -------- | -------- | -------- |
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# Partition Memory Map Example
This example demonstrates how to use `esp_partition_mmap` to configure MMU and map a partition into memory address space for read operations.
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# Example Flow
The example uses a [custom partition table](./partitions_example.csv), with a data partition `storage` used for demonstration. Before mapping this partition to memory,
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data is written to the partition used for verification.
The partition API function `esp_partition_mmap` is used to get a pointer to the mapped memory region and a handle to the mapping. The pointer is used to transparently read back the
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verification data written previously. Once the data written and read are verified to be the same, the function `spi_flash_munmap` is used to release the mapping.
### Output
```
I (309) example: Written sample data to partition: ESP-IDF Partition Memory Map Example
I (309) example: Mapped partition to data memory address 0x3f410000
I (319) example: Read sample data from partition using mapped memory: ESP-IDF Partition Memory Map Example
I (329) example: Data matches
I (329) example: Unmapped partition from data memory
I (339) example: Example end
```
# Others
Detailed functional description of partition API is provided in [documentation](https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/storage/spi_flash.html).
See the README.md file in the upper level 'examples' directory for more information about examples.