File System AT Commands
Note
The File System AT commands are enable by default and cannot be disabled.
AT+FS
command performs corresponding operations in theAT
directory of the file system.AT+CERT
command performs corresponding operations in theCERT
directory of the file system.If you want to preload files, refer to Preload Example.
AT+FS
Function Description
Perform file system operations, including deleting files, reading files, writing files, getting file sizes, and listing files.
Command Format
AT+FS=<operation>[,<filename>,<offset>,<length>]
Response Format
Successful Response:
OK
Error Response:
ERROR: <error_no>
Parameters
- <operation>:
File operation type
0: List files in directory
1: Delete file
2: Get file size
3: Read file
4: Write file
- <filename>:
File name string
Length not exceeding 125 bytes
- <offset>:
Starting position for reading or writing
- <length>:
Length to read or write
Error Codes
1: Format error
2: Operation failed
Note
When <operation> is set to write, the system will enter Transparent Transmission (TT) Mode mode.
Examples
List files in the directory:
AT+FS=0 OK
Delete the file
test.txt
:AT+FS=1,"test.txt" OK
Get size of file
data.bin
:AT+FS=2,"data.bin" +FS: 1024 OK
Read 50 bytes from the file
log.txt
starting at offset 100:AT+FS=3,"log.txt",100,50 +FS: <read data> OK
Write 100 bytes of data to the file
new.dat
:AT+FS=4,"new.dat",0,100 >>> <send 100 bytes of data> OK
AT+CERT
Function Description
Query the certificate components of the server or client
Command Format
AT+CERT=<role>,<index>
Response Format
Successful Response:
<Certificate name 1>
<Certificate content 1>
<Certificate name 2>
<Certificate content 2>
<Certificate name 3>
<Certificate content 3>
OK
Error Response:
ERROR: <error_no>
Parameters
- <role>:
Certificate component type
0
: Client1
: Server
- <index>:
Certificate component index
Range: 1~10
Error Codes
1: Parameter error