FileSystem AT Commands

[中文]

Introduction

Important

The default AT firmware does not support the AT commands listed on this page. If you need ESP32-C5 to support FileSystem commands, you can compile the ESP-AT project by following the steps in Compile ESP-AT Project Locally documentation. In the project configuration during the fifth step, make the following selections:

  • Enable Component config > AT > AT FS command support

AT+FS: Filesystem Operations

Set Command

Command:

AT+FS=<type>,<operation>,<filename>,<offset>,<length>

Response:

OK

Parameters

  • <type>: Filesystem type, LittleFS is recommended. You can select it in Component config > AT > AT FS command support > Filesystem type for AT FS command.

    • 0: FATFS

    • 1: LittleFS

  • <operation>:

    • 0: delete file.

    • 1: write file.

    • 2: read file.

    • 3: query the size of the file.

    • 4: list files in a specific directory. Only root directory is currently supported.

    • 5: calculate the MD5 hash of a file for verifying file integrity.

    • 6: query the free space and total space of the filesystem.

  • <offset>: apply to writing and reading operations only.

  • <length>: data length, applying to writing and reading operations only.

Notes

  • This command will automatically mount the filesystem. After the AT+FS filesystem operation is all done, it is strongly recommended to use the AT+FSMOUNT=0 command to unmount the filesystem to free a large amount of RAM space.

  • Please make sure that you have downloaded at_customize.bin before using this command. For more details, refer to ESP-IDF Partition Tables and How to Customize Partitions.

  • If the length of the read data is greater than the actual file length, only the actual data length of the file will be returned.

  • If the operator is write, wrap return > after the write command, then you can send the data that you want to write. The length should be parameter <length>.

  • If you need to ensure that the AT firmware is compatible with the legacy FATFS partition after an OTA upgrade, please select FatFS (legacy partition, upgrade only, READ HELP FIRST) at the following configuration path: Component config > AT > AT FS command support > Filesystem type for AT FS command.

Example

// delete a file.
AT+FS=1,0,"filename"

// write 10 bytes to offset 100 of a file.
AT+FS=1,1,"filename",100,10

// read 100 bytes from offset 0 of a file.
AT+FS=1,2,"filename",0,100

// list all files in the root directory.
AT+FS=1,4,"."

// calculate the MD5 hash of a file.
AT+FS=1,5,"filename"

// query the free space and total space of the filesystem.
AT+FS=1,6

AT+FSMOUNT: Mount/Unmount Filesystem

Set Command

Command:

AT+FSMOUNT=<mount>

Response:

OK

Parameters

  • <mount>:

    • 0: Unmount filesystem

    • 1: Mount filesystem

Notes

  • After the AT+FS filesystem operation is all done, it is strongly recommended to use the AT+FSMOUNT=0 command to unmount the filesystem to free a large amount of RAM space.

Example

// unmount the filesystem manually
AT+FSMOUNT=0

// mount the filesystem manually
AT+FSMOUNT=1

Provide feedback about this document