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QSPIFBlockDevice

QSPIFBlockDevice class hierarchy

The QSPIFBlockDevice is a block device driver for NOR-based QSPI Flash devices that support the SFDP standard. NOR-based QSPI Flash supports up to 4 bits per cycle of instruction, address and data. SFDP-based QSPI Flash supports variable bus modes (single, dual and quad), several sector erase size types and multiple regions of sector size types.

For more information about the SFDP JEDEC standard, please see its documentation.

QSPIFBlockDevice class reference

Public Member Functions
 QSPIFBlockDevice (PinName io0, PinName io1, PinName io2, PinName io3, PinName sclk, PinName csel, int clock_mode, int freq=MBED_CONF_QSPIF_QSPI_FREQ)
 Create QSPIFBlockDevice - An SFDP based Flash Block Device over QSPI bus. More...
virtual int init ()
 Initialize a block device. More...
virtual int deinit ()
 Deinitialize a block device. More...
 ~QSPIFBlockDevice ()
 Desctruct QSPIFBlockDevie. 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 a eraseable block. More...
virtual mbed::bd_size_t get_erase_size (mbed::bd_addr_t addr)
 Get the size of minimal eraseable 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 bd_size_t get_erase_size (bd_addr_t addr) const
 Get the size of an erasable block given address. More...
bool is_valid_read (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block read validity. More...
bool is_valid_program (bd_addr_t addr, bd_size_t size) const
 Convenience function for checking block program validity. More...
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...

QSPIFBlockDevice example

This example creates a QSPIFBlockDevice, erases a sector, programs it, reads the block back and cleans up.

/* mbed Microcontroller Library
 * Copyright (c) 2006-2013 ARM Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "mbed.h"
#include <stdio.h>
#include <algorithm>
#include "QSPIFBlockDevice.h"


QSPIFBlockDevice bd(QSPI_FLASH1_IO0, QSPI_FLASH1_IO1, QSPI_FLASH1_IO2, QSPI_FLASH1_IO3,
                            QSPI_FLASH1_SCK, QSPI_FLASH1_CSN, QSPIF_POLARITY_MODE_0, MBED_CONF_QSPIF_QSPI_FREQ);

// Entry point for the example
int main() {
    printf("--- Mbed OS QSPIF block device example ---\n");

    // Initialize the block device
    int err = bd.init();
    printf("bd.init -> %d\n", err);
    
    int erase_val = bd.get_erase_value();

    // Get device geometry
    bd_size_t read_size    = bd.get_read_size();
    bd_size_t program_size = bd.get_program_size();
    bd_size_t erase_size   = bd.get_erase_size();
    bd_size_t size         = bd.size();

    printf("--- Block device geometry ---\n");
    printf("read_size:    %lld B\n", read_size);
    printf("program_size: %lld B\n", program_size);
    printf("erase_size:   %lld B\n", erase_size);
    printf("size:         %lld B\n", size);
    printf("---\n");

    // Allocate a block with enough space for our data, aligned to the
    // nearest program_size. This is the minimum size necessary to write
    // data to a block.
    size_t buffer_size = sizeof("Hello Storage!") + program_size-1;
    buffer_size = buffer_size - (buffer_size % program_size);
    char *buffer = new char[buffer_size];

    // Read what is currently stored on the block device. We haven't written
    // yet so this may be garbage
    printf("bd.read(%p, %d, %d)\n", buffer, 0, buffer_size);
    err = bd.read(buffer, 0, buffer_size);
    printf("bd.read -> %d\n", err);

    printf("--- Stored data ---\n");
    for (size_t i = 0; i < buffer_size; i += 16) {
        for (size_t j = 0; j < 16; j++) {
            if (i+j < buffer_size) {
                printf("%02x ", buffer[i+j]);
            } else {
                printf("   ");
            }
        }

        printf(" %.*s\n", buffer_size - i, &buffer[i]);
    }
    printf("---\n");

    // Update buffer with our string we want to store
    strncpy(buffer, "Hello Storage!", buffer_size);

    // Write data to first block, write occurs in two parts,
    // an erase followed by a program
    printf("bd.erase(%d, %lld)\n", 0, erase_size);
    err = bd.erase(0, erase_size);
    printf("bd.erase -> %d\n", err);

    printf("bd.program(%p, %d, %d)\n", buffer, 0, buffer_size);
    err = bd.program(buffer, 0, buffer_size);
    printf("bd.program -> %d\n", err);

    // Clobber the buffer so we don't get old data
    memset(buffer, 0xcc, buffer_size);

    // Read the data from the first block, note that the program_size must be
    // a multiple of the read_size, so we don't have to check for alignment
    printf("bd.read(%p, %d, %d)\n", buffer, 0, buffer_size);
    err = bd.read(buffer, 0, buffer_size);
    printf("bd.read -> %d\n", err);

    printf("--- Stored data ---\n");
    for (size_t i = 0; i < buffer_size; i += 16) {
        for (size_t j = 0; j < 16; j++) {
            if (i+j < buffer_size) {
                printf("%02x ", buffer[i+j]);
            } else {
                printf("   ");
            }
        }

        printf(" %.*s\n", buffer_size - i, &buffer[i]);
    }
    printf("---\n");

    // Deinitialize the block device
    printf("bd.deinit()\n");
    err = bd.deinit();
    printf("bd.deinit -> %d\n", err);

    printf("--- done! ---\n");
}


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