STM32 SD library for Arduino
With an STM32 board with SD card slot availability, this library enables reading and writing on SD card using SD card slot of a STM32 board (NUCLEO, DISCOVERY, ...). This library is for SD card slots connected to the SDIO-/SDMMC-hardware of the processor. For slots connected to SPI-hardware use the standard Arduino SD library.
This library follow Arduino API.
For more information about it, please visit: http://www.arduino.cc/en/Reference/SD
Dependency
This library is based on FatFs, a generic FAT file system module for small embedded systems.
http://elm-chan.org/fsw/ff
The FatFs has been ported as Arduino library here. The STM32SD library depends on it.
Configuration
FatFs
The FatFs has several user defined options, which is specified from within the ffconf.h
file.
This library provides a default user defined options file named ffconf_default.h
.
User can provide his own defined options by adding his configuration in a file named
ffconf_custom.h
at sketch level or in variant folder.
SD
Some default definitions can be overridden using:
-
board
variant.h
-
build_opt.h
: see Customize build options -
hal_conf_extra.h
: see HAL configuration
SD configurations
-
SD_INSTANCE
: some STM32 can have 2 SD peripheralsSDMMC1
andSDMMC2
, note that this library can managed only one peripheralSDMMC1
(default)SDMMC2
-
SD_HW_FLOW_CTRL
: specifies whether the SDMMC hardware flow control is enabled or disabledSD_HW_FLOW_CTRL_ENABLE
SD_HW_FLOW_CTRL_DISABLE
(default)
-
SD_BUS_WIDE
: specifies the SDMMC bus widthSD_BUS_WIDE_1B
SD_BUS_WIDE_4B
(default)SD_BUS_WIDE_8B
SD Transceiver
-
SD_TRANSCEIVER_MODE
: specifies whether external Transceiver is enabled or disabled. Available only on some STM32SDMMC_TRANSCEIVER_ENABLE
SDMMC_TRANSCEIVER_DISABLE
(default)
-
SD_TRANSCEIVER_EN
pin number to enable the level shifter -
SD_TRANSCEIVER_SEL
pin number for voltage selection
SD detect and timeout
-
SD_DETECT_PIN
pin number -
SD_DATATIMEOUT
constant for Read/Write block