| .. _littlefs-sample: |
| |
| littlefs File System Sample Application |
| ####################################### |
| |
| Overview |
| ******** |
| |
| This sample app demonstrates use of Zephyr's :ref:`file system API |
| <file_system>` over `littlefs`_, using a file system with a file that |
| counts the number of times the system has booted. Other information |
| about the file system is also displayed. |
| |
| .. _littlefs: |
| https://github.com/ARMmbed/littlefs |
| |
| Requirements |
| ************ |
| |
| The partition labeled "storage" will be used for the file system; see |
| :ref:`flash_partitions`. If that area does not already have a |
| compatible littlefs file system its contents will be replaced by an |
| empty file system. You will see diagnostics like this:: |
| |
| [00:00:00.010,192] <inf> littlefs: LittleFS version 2.0, disk version 2.0 |
| [00:00:00.010,559] <err> littlefs: Corrupted dir pair at 0 1 |
| [00:00:00.010,559] <wrn> littlefs: can't mount (LFS -84); formatting |
| |
| The error and warning are normal for a new file system. |
| |
| After the file system is mounted you'll also see:: |
| |
| [00:00:00.182,434] <inf> littlefs: filesystem mounted! |
| [00:00:00.867,034] <err> fs: failed get file or dir stat (-2) |
| |
| This error is also normal for Zephyr not finding a file (the boot count, |
| in this case). |
| |
| Building and Running |
| ******************** |
| |
| This example should work on any board that provides a "storage" |
| partition. Two tested board targets are described below. |
| |
| You can set ``CONFIG_APP_WIPE_STORAGE`` to force the file system to be |
| recreated. |
| |
| NRF52840 Development Kit |
| ======================== |
| |
| On this device the file system will be placed in the SOC flash. |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/subsys/fs/littlefs |
| :board: nrf52840_pca10056 |
| :goals: build |
| :compact: |
| |
| Particle Xenon |
| ============== |
| |
| On this device the file system will be placed on the external SPI NOR |
| flash memory. |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/subsys/fs/littlefs |
| :board: particle_xenon |
| :goals: build |
| :compact: |