SdFatFs Class

SdFatFs Class

Description
Defines a class of SD FAT File system.
Syntax
class SdFatFs
Members
Public Constructors
SdFatFs::SdFatFs Constructs a SdFatFs object.
SdFatFs::~SdFatFs Destructs a SdFatFs object.
Public Methods
SdFatFs::begin Initialize SD FAT File System.
SdFatFs::end Deinitialize SD FAT File System.
SdFatFs::*getRootPath Get the root path of the SD FAT File System.
SdFatFs::readDir List items under a specific folder.
SdFatFs::mkdir Create folder.
SdFatFs::rm Remove folder or file.
SdFatFs::isDir Check if a specific path is a directory.
SdFatFs::isFile Check if a specific path is a file.
SdFatFs::getLastModTime Get the last modified time for a file or directory.
SdFatFs::setLastModTime Set the last modified time for a file or directory.
SdFatFs::status Return the current status of SD.
SdFatFs::open Open a file.

SdFatFs::begin

Description
Initialize SD FAT File System.
Syntax
int SdFatFs::begin(void);
Parameters
The function requires no input parameter.
Returns
Returns “0” if success, else returns a negative value.
Example Code
Example: create_folder; file_read_write; get_file_attribute; last_modified_time; list_root_files.
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::end

Description
De-initialize SD FAT File System.
Syntax
int SdFatFs::end(void);
Parameters
The function requires no input parameter.
Returns
Returns “0” if success, else returns a negative value.
Example Code
Example: create_folder; file_read_write; get_file_attribute; last_modified_time; list_root_files.
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::*getRootPath

Description
Get the root path of the SD FAT File System. The logical volume character is starting from ‘0’, so the root path would like “0:/”.
Syntax
char *SdFatFs::getRootPath(void);
Parameters
The function requires no input parameter.
Returns
The function returns the root path.
Example Code
Example: create_folder; file_read_write; get_file_attribute; last_modified_time; list_root_files.
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::readDir

Description
List items under a specific folder. List items under a specific folder and store the result in the buffer that user specified. Each item is separated by ‘\0’.
Syntax
int SdFatFs::readDir(char *path, char *result_buf, unsigned int bufsize);
Parameters
path: The absolute directory path to be listed. result_buf: The buffer to be stored results. bufsize: The size of result_buf. If results exceed this size, then the results larger than this size would be discarded.
Returns
Returns “0” if success, else returns a negative value.
Example Code
Example: get_file_attribute; list_root_files
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::mkdir

Description
Create folder.
Syntax
int SdFatFs::mkdir(char *absolute_path);
Parameters
absolute_path: The absolute directory path to be created
Returns
Returns “0” if success, else returns a negative value.
Example Code
Example: create_folder
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::rm

Description
Remove folder or file.
Syntax
int SdFatFs::rm(char *absolute_path);
Parameters
absolute_path: The absolute directory or file path to be deleted
Returns
Returns “0” if success, else returns a negative value.
Example Code
NA
Notes and Warnings
Include “SdFatFs.h” to use the class function.
 

SdFatFs::isDir

Description
Check if a specific path is a directory.
Syntax
unsigned char SdFatFs::isDir(char *absolute_path);
Parameters
absolute_path: The absolute path to be queried
Returns
The function returns “1” if it is a directory, else returns “0”.
Example Code
Example: get_file_attribute
Notes and Warnings
Include “SdFatFs.h” to use the class function.

SdFatFs::isFile

Description
Check if a specific path is a file.
Syntax
unsigned char SdFatFs::isFile(char *absolute_path);
Parameters
absolute_path: The absolute path to be queried
Returns
The function returns “1” if it is a directory, else returns “0”.
Example Code
Example: get_file_attribute
Notes and Warnings
Include “SdFatFs.h” to use the class function.

SdFatFs::getLastModTime

Description
Get the last modified time for a file or directory.
Syntax
int SdFatFs::getLastModTime(char *absolute_path, uint16_t *year, uint16_t *month, uint16_t *date, uint16_t *hour, uint16_t *minute, uint16_t *second);
Parameters
absolute_path: The absolute path to be queried. year: The value of the year. month: The value of the month. date: The value of the date. hour: The value of an hour. minute: The value of a minute. second: field “second” contains no valid information in the current version.
Returns
The function returns “0” if success, otherwise returns a negative value for failure.
Example Code
Example: last_modified_time
Notes and Warnings
Include “SdFatFs.h” to use the class function.

SdFatFs::setLastModTime

Description
Set the last modified time for a file or directory. Ameba doesn’t have built-in RTC. So we manually change file/directory last modified time.
Syntax
int SdFatFs::setLastModTime(char *absolute_path, uint16_t year, uint16_t month, uint16_t date, uint16_t hour, uint16_t minute, uint16_t second);
Parameters
absolute_path: The absolute path to be queried. year: The value of the year. month: The value of the month. date: The value of the date. hour: The value of an hour. minute: The value of a minute. second: field “second” contains no valid information in the current version.
Returns
The function returns “0” if success, otherwise returns a negative value for failure.
Example Code
Example: last_modified_time
Notes and Warnings
Include “SdFatFs.h” to use the class function.

SdFatFs::open

Description
Open a file.
Syntax
SdFatFile SdFatFs::open(char *absolute_path);
Parameters
absolute_path: The path to a file.
Returns
The file object is an instance of SdFatFile.
Example Code
Example: create_folder; file_read_write; get_file_attribute; last_modified_time; list_root_files.
Notes and Warnings
Include “SdFatFs.h” to use the class function.

SdFatFs::status

Description
Return the current status of SD.
Syntax
int SdFatFs::status(void);
Parameters
The function requires no input parameter.
Returns
Function returns “1” if ready to use, else return “0” if the status is inactivating or abnormal.
Example Code
NA
Notes and Warnings
Include “SdFatFs.h” to use the class function.
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