• isDirectory()
• openNextFile()
• rewindDirectory()

The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It uses short 8.3 names for files. The file names passed to the SD library functions can include paths separated by forward-slashes, /, e.g. "directory/filename.txt". Because the working directory is always the root of the SD card, a name refers to the same file whether or not it includes a leading slash (e.g. "/file.txt" is equivalent to "file.txt"). As of version 1.0, the library supports opening multiple files.

The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It uses short 8.3 names for files. The file names passed to the SD library functions can include paths separated by forward-slashes, /, e.g. "directory/filename.txt". Because the working directory is always the root of the SD card, a name refers to the same file whether or not it includes a leading slash (e.g. "/file.txt" is equivalent to "file.txt").

Notes on using the Library and various shields

• CardInfo: Get information about a SD card

Notes on using the Library and various shields

Using SD shields and adapters

Various manufacturers have created boards and shields that incorporate the SD card. However, not all of them use the same SS pin. For example, the Sparkfun shield uses pin 8, while the Arduino Ethernet Shield uses pin 4. Below are wiring and code examples using common SD shields and boards.

• Adafruit MicroSD card breakout board?
• Arduino Ethernet Shield with SD adapter?
• Sparkfun microSD shield?

• Adafruit MicroSD card breakout board?

Using different SD shields and adapters

• MicroSD card breakout board?
• Arduino Ethernet Shield with SD adapter?
• Sparkfun microSD shield?

• Datalogger: Log data from three analog sensors to a SD card using the SD library
• DumpFile: Read a file from a SD card using the SD library and send it over the serial port
• Files: Create and destroy a file on a SD card
• ReadWrite: Read and write data to and from a file on a SD card

Examples

• Datalogger: Log data from three analog sensors to a SD card using the SD library.
• DumpFile: Read a file from a SD card using the SD library and send it over the serial port.
• Files: Create and destroy a file on a SD card.
• ReadWrite: Read and write data to and from a file on a SD card.

SD Library

• open()
• remove()

• available()
• close()
• flush()
• peek()
• position()

• seek()
• size()
• read()

The communication between the microcontroller and the SD card uses SPI, which takes place on digital pins 11, 12, and 13 (on most Arduino boards) or 50, 51, and 52 (Arduino Mega). Additionally, another pin must be used to select the SD card. This can be the hardware SS pin - pin 10 (on most Arduino boards) or pin 53 (on the Mega) - or another pin specified in the call to SD.begin(). Note that even if you don't use the hardware SS pin, it must be left as an output or the SD library won't work.

The communication between the microcontroller and the SD card uses SPI, which takes place on digital pins 11, 12, and 13 (on most Arduino boards) or 50, 51, and 52 (Arduino Mega). Additionally, another pin must be used to select the SD card. This can be the hardware SS pin - pin 10 (on most Arduino boards) or pin 53 (on the Mega) - or another pin specified in the call to SD.begin(). Note that even if you don't use the hardware SS pin, it must be left as an output or the SPI communication won't work.

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The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It only supports one open file at a time and only uses short 8.3 file names. The file names passed to the SD library functions can include paths separated by forward-slashes, /, e.g. "directory/filename.txt". Because the working directory is always the root of the SD card, a name refers to the same file whether or not it includes a leading slash (e.g. "/file.txt" is equivalent to "file.txt").

The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It only support short 8.3 file names. The file names passed to the SD library functions can include paths separated by forward-slashes, /, e.g. "directory/filename.txt". Because the working directory is always the root of the SD card, a name refers to the same file whether or not it includes a leading slash (e.g. "/file.txt" is equivalent to "file.txt").

The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It only support short 8.3 file names. The file names passed to the SD library functions can include paths separated by forward-slashes, /, e.g. "directory/filename.txt".

• println()

The SD class provides functions for accessing the SD card and manipulating its files and directories.

The File class allows for reading from and writing to individual files on the SD card.

• print()
• [FilePrintln | println()]]
• write()
• read()
• peek()
• available()
• flush()
• close()

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The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield. It is built on sdfatlib by William Greiman. The library supports FAT16 and FAT32 file systems on standard SD cards and SDHC cards. It only support short 8.3 file names.

SD class

• begin()
• open()
• exists()
• remove()
• mkdir()
• rmdir()

File class

SD Library (coming in Arduino 0022)

The SD library allows for reading from and writing to SD cards, e.g. on the Arduino Ethernet Shield.

The communication between the microcontroller and the SD card uses SPI, which takes place on digital pins 11, 12, and 13 (on most Arduino boards) or 50, 51, and 52 (Arduino Mega). Additionally, another pin must be used to select the SD card. This can be the hardware SS pin - pin 10 (on most Arduino boards) or pin 53 (on the Mega) - or another pin specified in the call to SD.begin(). Note that even if you don't use the hardware SS pin, it must be left as an output or the SPI communication won't work.