Mbed OS Reference | DataFlashBlockDevice.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2016 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.
  */
 
 #ifndef MBED_DATAFLASH_BLOCK_DEVICE_H
 #define MBED_DATAFLASH_BLOCK_DEVICE_H
 
 #include "platform/PlatformMutex.h"
 #include "PinNames.h"
 #include "features/storage/blockdevice/BlockDevice.h"
 #include "drivers/SPI.h"
 #include "drivers/DigitalOut.h"
 
 
 /** BlockDevice for DataFlash flash devices
  *
  *  @code
  *  // 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();
  *  }
  *  @endcode
  */
 class DataFlashBlockDevice : public mbed::BlockDevice {
 public:
     /** Creates a DataFlashBlockDevice on a SPI bus specified by pins
      *
      *  @param mosi     SPI master out, slave in pin
      *  @param miso     SPI master in, slave out pin
      *  @param sclk     SPI clock pin
      *  @param csel     SPI chip select pin
      *  @param nowp     GPIO not-write-protect
      *  @param freq     Clock speed of the SPI bus (defaults to 40MHz)
      */
     DataFlashBlockDevice(PinName mosi,
                          PinName miso,
                          PinName sclk,
                          PinName csel,
                          int freq = MBED_CONF_DATAFLASH_SPI_FREQ,
                          PinName nowp = NC);
 
     /** Initialize a block device
      *
      *  @return         0 on success or a negative error code on failure
      */
     virtual int init();
 
     /** Deinitialize a block device
      *
      *  @return         0 on success or a negative error code on failure
      */
     virtual int deinit();
 
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to write blocks to
      *  @param addr     Address of block to begin reading from
      *  @param size     Size to read in bytes, must be a multiple of read block size
      *  @return         0 on success, negative error code on failure
      */
     virtual int read(void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Program blocks to a block device
      *
      *  The blocks must have been erased prior to being programmed
      *
      *  @param buffer   Buffer of data to write to blocks
      *  @param addr     Address of block to begin writing to
      *  @param size     Size to write in bytes, must be a multiple of program block size
      *  @return         0 on success, negative error code on failure
      */
     virtual int program(const void *buffer, mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Erase blocks on a block device
      *
      *  The state of an erased block is undefined until it has been programmed
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
      *  @return         0 on success, negative error code on failure
      */
     virtual int erase(mbed::bd_addr_t addr, mbed::bd_size_t size);
 
     /** Get the size of a readable block
      *
      *  @return         Size of a readable block in bytes
      */
     virtual mbed::bd_size_t get_read_size() const;
 
     /** Get the size of a programable block
      *
      *  @return         Size of a programable block in bytes
      *  @note Must be a multiple of the read size
      */
     virtual mbed::bd_size_t get_program_size() const;
 
     /** Get the size of a eraseable block
      *
      *  @return         Size of a eraseable block in bytes
      *  @note Must be a multiple of the program size
      */
     virtual mbed::bd_size_t get_erase_size() const;
 
     /** Get the size of an erasable block given address
      *
      *  @param addr     Address within the erasable block
      *  @return         Size of an erasable block in bytes
      *  @note Must be a multiple of the program size
      */
     virtual mbed::bd_size_t get_erase_size(mbed::bd_addr_t addr) const;
 
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes
      */
     virtual mbed::bd_size_t size() const;
 
     /** Get the BlockDevice class type.
      *
      *  @return         A string represent the BlockDevice class type.
      */
     virtual const char *get_type() const;
 
 private:
     // Master side hardware
     mbed::SPI _spi;
     mbed::DigitalOut _cs;
     mbed::DigitalOut _nwp;
 
     // Device configuration
     uint32_t _device_size;
     uint16_t _page_size;
     uint16_t _block_size;
     bool _is_initialized;
     uint32_t _init_ref_count;
 
     // Internal functions
     uint16_t _get_register(uint8_t opcode);
     void _write_command(uint32_t command, const uint8_t *buffer, uint32_t size);
     void _write_enable(bool enable);
     int _sync(void);
     int _write_page(const uint8_t *buffer, uint32_t addr, uint32_t offset, uint32_t size);
     uint32_t _translate_address(bd_addr_t addr);
 
     // Mutex for thread safety
     mutable PlatformMutex _mutex;
 };
 
 
 #endif  /* MBED_DATAFLASH_BLOCK_DEVICE_H */
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