takashi kadono / Mbed OS Nucleo_446

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependencies:   ssd1331

Embed: (wiki syntax)

« Back to documentation index

DataFlashBlockDevice Class Reference
Public Member Functions | Static Public Member Functions

DataFlashBlockDevice Class Reference

BlockDevice for DataFlash flash devices. More...

#include <DataFlashBlockDevice.h>

Inherits BlockDevice.

Public Member Functions

 DataFlashBlockDevice (PinName mosi, PinName miso, PinName sclk, PinName csel, int freq=MBED_CONF_DATAFLASH_SPI_FREQ, PinName nowp=NC)
 Creates a DataFlashBlockDevice on a SPI bus specified by pins.
virtual int init ()
 Initialize a block device.
virtual int deinit ()
 Deinitialize a block device.
virtual int read (void *buffer, bd_addr_t addr, bd_size_t size)
 Read blocks from a block device.
virtual int program (const void *buffer, bd_addr_t addr, bd_size_t size)
 Program blocks to a block device.
virtual int erase (bd_addr_t addr, bd_size_t size)
 Erase blocks on a block device.
virtual bd_size_t get_read_size () const
 Get the size of a readable block.
virtual bd_size_t get_program_size () const
 Get the size of a programable block.
virtual bd_size_t get_erase_size () const
 Get the size of a eraseable block.
virtual bd_size_t get_erase_size (bd_addr_t addr) const
 Get the size of an erasable block given address.
virtual bd_size_t size () const
 Get the total size of the underlying device.
virtual int sync ()
 Ensure data on storage is in sync with the driver.
virtual int trim (bd_addr_t addr, bd_size_t size)
 Mark blocks as no longer in use.
virtual int get_erase_value () const
 Get the value of storage when erased.
bool is_valid_read (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block read validity.
bool is_valid_program (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block program validity.
bool is_valid_erase (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block erase validity.

Static Public Member Functions

static BlockDevice * get_default_instance ()
 Return the default block device.

Detailed Description

BlockDevice for DataFlash flash devices. 

  // Here's an example using the AT45DB on the K64F
  #include "mbed.h"
  #include "DataFlashBlockDevice.h"

  // Create DataFlash on SPI bus with PTE5 as chip select
  DataFlashBlockDevice dataflash(PTE2, PTE4, PTE1, PTE5);

  // Create DataFlash on SPI bus with PTE6 as write-protect
  DataFlashBlockDevice dataflash2(PTE2, PTE4, PTE1, PTE5, PTE6);

  int main() {
      printf("dataflash test\n");

      // Initialize the SPI flash device and print the memory layout
      dataflash.init();
      printf("dataflash size: %llu\n", dataflash.size());
      printf("dataflash read size: %llu\n", dataflash.get_read_size());
      printf("dataflash program size: %llu\n", dataflash.get_program_size());
      printf("dataflash erase size: %llu\n", dataflash.get_erase_size());

      // Write "Hello World!" to the first block
      char *buffer = (char*)malloc(dataflash.get_erase_size());
      sprintf(buffer, "Hello World!\n");
      dataflash.erase(0, dataflash.get_erase_size());
      dataflash.program(buffer, 0, dataflash.get_erase_size());

      // Read back what was stored
      dataflash.read(buffer, 0, dataflash.get_erase_size());
      printf("%s", buffer);

      // Deinitialize the device
      dataflash.deinit();
  }

Definition at line 62 of file DataFlashBlockDevice.h.

Constructor & Destructor Documentation

DataFlashBlockDevice ( PinName  mosi,
PinName  miso,
PinName  sclk,
PinName  csel,
int  freq = MBED_CONF_DATAFLASH_SPI_FREQ,
PinName  nowp = NC 
)

Creates a DataFlashBlockDevice on a SPI bus specified by pins.

Parameters:
mosiSPI master out, slave in pin
misoSPI master in, slave out pin
sclkSPI clock pin
cselSPI chip select pin
nowpGPIO not-write-protect
freqClock speed of the SPI bus (defaults to 40MHz)

Definition at line 133 of file DataFlashBlockDevice.cpp.

Member Function Documentation

int deinit (  ) [virtual]

Deinitialize a block device.

Returns:
0 on success or a negative error code on failure

Implements BlockDevice.

Definition at line 287 of file DataFlashBlockDevice.cpp.

int erase ( bd_addr_t  addr,
bd_size_t  size 
) [virtual]

Erase blocks on a block device.

The state of an erased block is undefined until it has been programmed

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

Reimplemented from BlockDevice.

Definition at line 417 of file DataFlashBlockDevice.cpp.

MBED_WEAK BlockDevice * get_default_instance (  ) [static, inherited]

Return the default block device.

Returns the default BlockDevice base on 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() themselves - the default definition is weak, and calls get_target_default_instance().

Definition at line 35 of file SystemStorage.cpp.

bd_size_t get_erase_size (  ) const [virtual]

Get the size of a eraseable block.

Returns:
Size of a eraseable block in bytes
Note:
Must be a multiple of the program size

Reimplemented from BlockDevice.

Definition at line 485 of file DataFlashBlockDevice.cpp.

bd_size_t get_erase_size ( bd_addr_t  addr ) const [virtual]

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 from BlockDevice.

Definition at line 492 of file DataFlashBlockDevice.cpp.

virtual int get_erase_value (  ) const [virtual, inherited]

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 erased storage

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

Definition at line 181 of file BlockDevice.h.

bd_size_t get_program_size (  ) const [virtual]

Get the size of a programable block.

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

Implements BlockDevice.

Definition at line 478 of file DataFlashBlockDevice.cpp.

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.

Definition at line 471 of file DataFlashBlockDevice.cpp.

int init (  ) [virtual]

Initialize a block device.

Returns:
0 on success or a negative error code on failure

Implements BlockDevice.

Definition at line 165 of file DataFlashBlockDevice.cpp.

bool is_valid_erase ( bd_addr_t  addr,
bd_size_t  size 
) const [inherited]

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

Definition at line 226 of file BlockDevice.h.

bool is_valid_program ( bd_addr_t  addr,
bd_size_t  size 
) const [inherited]

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

Definition at line 212 of file BlockDevice.h.

bool is_valid_read ( bd_addr_t  addr,
bd_size_t  size 
) const [inherited]

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

Definition at line 198 of file BlockDevice.h.

int program ( const void *  buffer,
bd_addr_t  addr,
bd_size_t  size 
) [virtual]

Program blocks to a block device.

The blocks must have been erased prior to being programmed

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:
0 on success, negative error code on failure

Implements BlockDevice.

Definition at line 351 of file DataFlashBlockDevice.cpp.

int read ( void *  buffer,
bd_addr_t  addr,
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:
0 on success, negative error code on failure

Implements BlockDevice.

Definition at line 306 of file DataFlashBlockDevice.cpp.

bd_size_t size (  ) const [virtual]

Get the total size of the underlying device.

Returns:
Size of the underlying device in bytes

Implements BlockDevice.

Definition at line 499 of file DataFlashBlockDevice.cpp.

virtual int sync (  ) [virtual, inherited]

Ensure data on storage is in sync with the driver.

Returns:
0 on success or a negative error code on failure

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

Definition at line 79 of file BlockDevice.h.

virtual int trim ( bd_addr_t  addr,
bd_size_t  size 
) [virtual, inherited]

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:
0 on success, negative error code on failure

Reimplemented in SDBlockDevice, and BufferedBlockDevice.

Definition at line 133 of file BlockDevice.h.

Generated on Tue Aug 9 2022 00:37:33 by  doxygen 1.7.2