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Public Member Functions | Static Public Member Functions
SDBlockDevice Class Reference

SDBlockDevice class. More...

#include <SDBlockDevice.h>

Inheritance diagram for SDBlockDevice:
BlockDevice

Public Member Functions

 SDBlockDevice (PinName mosi, PinName miso, PinName sclk, PinName cs, uint64_t hz=1000000, bool crc_on=0)
 Creates an SDBlockDevice on a SPI bus specified by pins. More...
 
virtual int init ()
 Initialize a block device. More...
 
virtual int deinit ()
 Deinitialize a block device. More...
 
virtual int read (void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size)
 Read blocks from a block device. More...
 
virtual int program (const void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size)
 Program blocks to a block device. More...
 
virtual int trim (mbed::bd_addr_t addr, mbed::bd_size_t size)
 Mark blocks as no longer in use. More...
 
virtual mbed::bd_size_t get_read_size () const
 Get the size of a readable block. More...
 
virtual mbed::bd_size_t get_program_size () const
 Get the size of a programmable block. More...
 
virtual mbed::bd_size_t size () const
 Get the total size of the underlying device. More...
 
virtual void debug (bool dbg)
 Enable or disable debugging. More...
 
virtual int frequency (uint64_t freq)
 Set the transfer frequency. More...
 
virtual const char * get_type () const
 Get the BlockDevice class type. More...
 
virtual int sync ()
 Ensure data on storage is in sync with the driver. More...
 
virtual int erase (bd_addr_t addr, bd_size_t size)
 Erase blocks on a block device. More...
 
virtual bd_size_t get_erase_size () const
 Get the size of an erasable block. More...
 
virtual bd_size_t get_erase_size (bd_addr_t addr) const
 Get the size of an erasable block given address. More...
 
virtual int get_erase_value () const
 Get the value of storage when erased. More...
 
virtual bool is_valid_read (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block read validity. More...
 
virtual bool is_valid_program (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block program validity. More...
 
virtual bool is_valid_erase (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block erase validity. More...
 

Static Public Member Functions

static BlockDeviceget_default_instance ()
 Return the default block device. More...
 

Detailed Description

SDBlockDevice class.

Access an SD Card using SPI bus

Definition at line 35 of file SDBlockDevice.h.

Constructor & Destructor Documentation

SDBlockDevice ( PinName  mosi,
PinName  miso,
PinName  sclk,
PinName  cs,
uint64_t  hz = 1000000,
bool  crc_on = 0 
)

Creates an SDBlockDevice on a SPI bus specified by pins.

Parameters
mosiSPI master out, slave in pin
misoSPI master in, slave out pin
sclkSPI clock pin
csSPI chip select pin
hzClock speed of the SPI bus (defaults to 1MHz)
crc_onEnable cyclic redundancy check (defaults to disabled)

Member Function Documentation

virtual void debug ( bool  dbg)
virtual

Enable or disable debugging.

Parameters
dbgState of debugging
virtual int deinit ( )
virtual

Deinitialize a block device.

Returns
BD_ERROR_OK(0) - success

Implements BlockDevice.

virtual int erase ( bd_addr_t  addr,
bd_size_t  size 
)
virtualinherited

Erase blocks on a block device.

The state of an erased block is undefined until it has been programmed, unless get_erase_value returns a non-negative byte value

Parameters
addrAddress of block to begin erasing
sizeSize to erase in bytes, must be a multiple of the erase block size
Returns
0 on success or a negative error code on failure

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 120 of file BlockDevice.h.

virtual int frequency ( uint64_t  freq)
virtual

Set the transfer frequency.

Parameters
freqTransfer frequency
Note
Max frequency supported is 25MHZ
static BlockDevice* get_default_instance ( )
staticinherited

Return the default block device.

Returns the default block device based on the configuration JSON. Use the components in target.json or application config to change the default block device.

An application can override all target settings by implementing BlockDevice::get_default_instance() - the default definition is weak, and calls get_target_default_instance().

virtual bd_size_t get_erase_size ( ) const
virtualinherited

Get the size of an erasable block.

Returns
Size of an erasable block in bytes
Note
Must be a multiple of the program size

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, BufferedBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 159 of file BlockDevice.h.

virtual bd_size_t get_erase_size ( bd_addr_t  addr) const
virtualinherited

Get the size of an erasable block given address.

Parameters
addrAddress within the erasable block
Returns
Size of an erasable block in bytes
Note
Must be a multiple of the program size

Reimplemented in SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, DataFlashBlockDevice, HeapBlockDevice, SPIFReducedBlockDevice, BufferedBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 170 of file BlockDevice.h.

virtual int get_erase_value ( ) const
virtualinherited

Get the value of storage when erased.

If get_erase_value returns a non-negative byte value, the underlying storage is set to that value when erased, and storage containing that value can be programmed without another erase.

Returns
The value of storage when erased, or -1 if you can't rely on the value of the erased storage

Reimplemented in QSPIFBlockDevice, SPIFBlockDevice, MBRBlockDevice, ChainingBlockDevice, SPIFReducedBlockDevice, BufferedBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, ProfilingBlockDevice, ObservingBlockDevice, FlashSimBlockDevice, ReadOnlyBlockDevice, and FlashIAPBlockDevice.

Definition at line 184 of file BlockDevice.h.

virtual mbed::bd_size_t get_program_size ( ) const
virtual

Get the size of a programmable block.

Returns
Size of a programmable block in bytes
Note
Must be a multiple of the read size

Implements BlockDevice.

virtual mbed::bd_size_t get_read_size ( ) const
virtual

Get the size of a readable block.

Returns
Size of a readable block in bytes

Implements BlockDevice.

virtual const char* get_type ( ) const
virtual

Get the BlockDevice class type.

Returns
A string representation of the BlockDevice class type.

Implements BlockDevice.

virtual int init ( )
virtual

Initialize a block device.

Returns
BD_ERROR_OK(0) - success BD_ERROR_DEVICE_ERROR - device driver transaction failed SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected SD_BLOCK_DEVICE_ERROR_UNUSABLE - unusable card SD_BLOCK_DEVICE_ERROR_CRC - crc error

Implements BlockDevice.

virtual bool is_valid_erase ( bd_addr_t  addr,
bd_size_t  size 
) const
virtualinherited

Convenience function for checking block erase validity.

Parameters
addrAddress of block to begin erasing
sizeSize to erase in bytes
Returns
True if erase is valid for underlying block device

Reimplemented in SlicingBlockDevice.

Definition at line 229 of file BlockDevice.h.

virtual bool is_valid_program ( bd_addr_t  addr,
bd_size_t  size 
) const
virtualinherited

Convenience function for checking block program validity.

Parameters
addrAddress of block to begin writing to
sizeSize to write in bytes
Returns
True if program is valid for underlying block device

Reimplemented in SlicingBlockDevice.

Definition at line 215 of file BlockDevice.h.

virtual bool is_valid_read ( bd_addr_t  addr,
bd_size_t  size 
) const
virtualinherited

Convenience function for checking block read validity.

Parameters
addrAddress of block to begin reading from
sizeSize to read in bytes
Returns
True if read is valid for underlying block device

Reimplemented in SlicingBlockDevice.

Definition at line 201 of file BlockDevice.h.

virtual int program ( const void *  buffer,
mbed::bd_addr_t  addr,
mbed::bd_size_t  size 
)
virtual

Program blocks to a block device.

Note
The blocks must be erased prior to programming
Parameters
bufferBuffer of data to write to blocks
addrAddress of block to begin writing to
sizeSize to write in bytes. Must be a multiple of program block size
Returns
BD_ERROR_OK(0) - success SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected SD_BLOCK_DEVICE_ERROR_CRC - crc error SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command SD_BLOCK_DEVICE_ERROR_NO_INIT - device is not initialized SD_BLOCK_DEVICE_ERROR_WRITE - SPI write error SD_BLOCK_DEVICE_ERROR_ERASE - erase error

Implements BlockDevice.

virtual int read ( void *  buffer,
mbed::bd_addr_t  addr,
mbed::bd_size_t  size 
)
virtual

Read blocks from a block device.

Parameters
bufferBuffer to write blocks to
addrAddress of block to begin reading from
sizeSize to read in bytes, must be a multiple of read block size
Returns
BD_ERROR_OK(0) - success SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected SD_BLOCK_DEVICE_ERROR_CRC - crc error SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter SD_BLOCK_DEVICE_ERROR_NO_RESPONSE - no response from device SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command

Implements BlockDevice.

virtual mbed::bd_size_t size ( ) const
virtual

Get the total size of the underlying device.

Returns
Size of the underlying device in bytes

Implements BlockDevice.

virtual int sync ( )
virtualinherited

Ensure data on storage is in sync with the driver.

Returns
0 on success or a negative error code on failure

Reimplemented in MBRBlockDevice, ChainingBlockDevice, ExhaustibleBlockDevice, SlicingBlockDevice, FlashSimBlockDevice, ObservingBlockDevice, ProfilingBlockDevice, BufferedBlockDevice, and ReadOnlyBlockDevice.

Definition at line 82 of file BlockDevice.h.

virtual int trim ( mbed::bd_addr_t  addr,
mbed::bd_size_t  size 
)
virtual

Mark blocks as no longer in use.

This function provides a hint to the underlying block device that a region of blocks is no longer in use and may be erased without side effects. Erase must still be called before programming, but trimming allows flash-translation-layers to schedule erases when the device is not busy.

Parameters
addrAddress of block to mark as unused
sizeSize to mark as unused in bytes, must be a multiple of erase block size
Returns
BD_ERROR_OK(0) - success SD_BLOCK_DEVICE_ERROR_NO_DEVICE - device (SD card) is missing or not connected SD_BLOCK_DEVICE_ERROR_CRC - crc error SD_BLOCK_DEVICE_ERROR_PARAMETER - invalid parameter SD_BLOCK_DEVICE_ERROR_UNSUPPORTED - unsupported command SD_BLOCK_DEVICE_ERROR_NO_INIT - device is not initialized SD_BLOCK_DEVICE_ERROR_ERASE - erase error

Reimplemented from BlockDevice.

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