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SPI Flash block device

SPIFBlockDevice class hierarchy

This API is a block device for NOR-based SPI flash devices that support SFDP.

Note: Multiple protocols exist for SPI flash devices. This driver is for the SFDP SPI flash protocol. If your device uses the DataFlash protocol, you need the DataflashBlockDevice

NOR-based SPI flash supports byte-sized read and writes, with an erase size of around 4 kbytes. An erase sets a block to all 1s, with successive writes clearing set bits.

To configure this class, please see our BlockDevice configuration documentation.

SPIFBlockDevice class reference

Public Member Functions
 SPIFBlockDevice (PinName mosi=NC, PinName miso=NC, PinName sclk=NC, PinName csel=NC, int freq=40000000)
 Creates a SPIFBlockDevice on a SPI bus specified by pins. More...
virtual int init ()
 Initialize a block device. More...
virtual int deinit ()
 Deinitialize a block device. More...
 ~SPIFBlockDevice ()
 Desctruct SPIFBlockDevice. 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 erase (mbed::bd_addr_t addr, mbed::bd_size_t size)
 Erase blocks on a block device. 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 programable block. More...
virtual mbed::bd_size_t get_erase_size () const
 Get the size of an erasable block. More...
virtual mbed::bd_size_t get_erase_size (mbed::bd_addr_t addr) const
 Get the size of minimal erasable sector size of given address. More...
virtual int get_erase_value () const
 Get the value of storage byte after it was erased. More...
virtual mbed::bd_size_t size () const
 Get the total size of the underlying device. 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 trim (bd_addr_t addr, bd_size_t size)
 Mark blocks as no longer in use. 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...

SPIFBlockDevice example

#include "mbed.h"
#include "SPIFBlockDevice.h"

// Create flash device on SPI bus with PTE5 as chip select
SPIFBlockDevice spif(PTE2, PTE4, PTE1, PTE5);

int main()
    printf("spif test\n");

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

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

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

    // Deinitialize the device

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