stm32h7xx_hal_sdram.c File Reference

SDRAM HAL module driver. This file provides a generic firmware to drive SDRAM memories mounted as external device. More...

#include "stm32h7xx_hal.h"

Detailed Description

SDRAM HAL module driver. This file provides a generic firmware to drive SDRAM memories mounted as external device.

Author

MCD Application Team

Attention

Copyright (c) 2017 STMicroelectronics. All rights reserved.

This software is licensed under terms that can be found in the LICENSE file in the root directory of this software component. If no LICENSE file comes with this software, it is provided AS-IS.

==============================================================================
                     ##### How to use this driver #####
==============================================================================
[..]
  This driver is a generic layered driver which contains a set of APIs used to
  control SDRAM memories. It uses the FMC layer functions to interface
  with SDRAM devices.
  The following sequence should be followed to configure the FMC to interface
  with SDRAM memories:

 (#) Declare a SDRAM_HandleTypeDef handle structure, for example:
        SDRAM_HandleTypeDef  hsdram

     (++) Fill the SDRAM_HandleTypeDef handle "Init" field with the allowed
          values of the structure member.

     (++) Fill the SDRAM_HandleTypeDef handle "Instance" field with a predefined
          base register instance for NOR or SDRAM device

 (#) Declare a FMC_SDRAM_TimingTypeDef structure; for example:
        FMC_SDRAM_TimingTypeDef  Timing;
    and fill its fields with the allowed values of the structure member.

 (#) Initialize the SDRAM Controller by calling the function HAL_SDRAM_Init(). This function
     performs the following sequence:

     (##) MSP hardware layer configuration using the function HAL_SDRAM_MspInit()
     (##) Control register configuration using the FMC SDRAM interface function
          FMC_SDRAM_Init()
     (##) Timing register configuration using the FMC SDRAM interface function
          FMC_SDRAM_Timing_Init()
     (##) Program the SDRAM external device by applying its initialization sequence
          according to the device plugged in your hardware. This step is mandatory
          for accessing the SDRAM device.

 (#) At this stage you can perform read/write accesses from/to the memory connected
     to the SDRAM Bank. You can perform either polling or DMA transfer using the
     following APIs:
     (++) HAL_SDRAM_Read()/HAL_SDRAM_Write() for polling read/write access
     (++) HAL_SDRAM_Read_DMA()/HAL_SDRAM_Write_DMA() for DMA read/write transfer

 (#) You can also control the SDRAM device by calling the control APIs HAL_SDRAM_WriteOperation_Enable()/
     HAL_SDRAM_WriteOperation_Disable() to respectively enable/disable the SDRAM write operation or
     the function HAL_SDRAM_SendCommand() to send a specified command to the SDRAM
     device. The command to be sent must be configured with the FMC_SDRAM_CommandTypeDef
     structure.

 (#) You can continuously monitor the SDRAM device HAL state by calling the function
     HAL_SDRAM_GetState()

 *** Callback registration ***
  =============================================
  [..]
    The compilation define  USE_HAL_SDRAM_REGISTER_CALLBACKS when set to 1
    allows the user to configure dynamically the driver callbacks.

    Use Functions HAL_SDRAM_RegisterCallback() to register a user callback,
    it allows to register following callbacks:
      (+) MspInitCallback    : SDRAM MspInit.
      (+) MspDeInitCallback  : SDRAM MspDeInit.
    This function takes as parameters the HAL peripheral handle, the Callback ID
    and a pointer to the user callback function.

    Use function HAL_SDRAM_UnRegisterCallback() to reset a callback to the default
    weak (overridden) function. It allows to reset following callbacks:
      (+) MspInitCallback    : SDRAM MspInit.
      (+) MspDeInitCallback  : SDRAM MspDeInit.
    This function) takes as parameters the HAL peripheral handle and the Callback ID.

    By default, after the HAL_SDRAM_Init and if the state is HAL_SDRAM_STATE_RESET
    all callbacks are reset to the corresponding legacy weak (overridden) functions.
    Exception done for MspInit and MspDeInit callbacks that are respectively
    reset to the legacy weak (overridden) functions in the HAL_SDRAM_Init
    and  HAL_SDRAM_DeInit only when these callbacks are null (not registered beforehand).
    If not, MspInit or MspDeInit are not null, the HAL_SDRAM_Init and HAL_SDRAM_DeInit
    keep and use the user MspInit/MspDeInit callbacks (registered beforehand)

    Callbacks can be registered/unregistered in READY state only.
    Exception done for MspInit/MspDeInit callbacks that can be registered/unregistered
    in READY or RESET state, thus registered (user) MspInit/DeInit callbacks can be used
    during the Init/DeInit.
    In that case first register the MspInit/MspDeInit user callbacks
    using HAL_SDRAM_RegisterCallback before calling HAL_SDRAM_DeInit
    or HAL_SDRAM_Init function.

    When The compilation define USE_HAL_SDRAM_REGISTER_CALLBACKS is set to 0 or
    not defined, the callback registering feature is not available
    and weak (overridden) callbacks are used.