RTEMS 6.1-rc4
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SRAM HAL module driver. This file provides a generic firmware to drive SRAM memories mounted as external device. More...
#include "stm32h7xx_hal.h"
SRAM HAL module driver. This file provides a generic firmware to drive SRAM memories mounted as external device.
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 SRAM memories. It uses the FMC layer functions to interface with SRAM devices. The following sequence should be followed to configure the FMC to interface with SRAM/PSRAM memories: (#) Declare a SRAM_HandleTypeDef handle structure, for example: SRAM_HandleTypeDef hsram; and: (++) Fill the SRAM_HandleTypeDef handle "Init" field with the allowed values of the structure member. (++) Fill the SRAM_HandleTypeDef handle "Instance" field with a predefined base register instance for NOR or SRAM device (++) Fill the SRAM_HandleTypeDef handle "Extended" field with a predefined base register instance for NOR or SRAM extended mode (#) Declare two FMC_NORSRAM_TimingTypeDef structures, for both normal and extended mode timings; for example: FMC_NORSRAM_TimingTypeDef Timing and FMC_NORSRAM_TimingTypeDef ExTiming; and fill its fields with the allowed values of the structure member. (#) Initialize the SRAM Controller by calling the function HAL_SRAM_Init(). This function performs the following sequence: (##) MSP hardware layer configuration using the function HAL_SRAM_MspInit() (##) Control register configuration using the FMC NORSRAM interface function FMC_NORSRAM_Init() (##) Timing register configuration using the FMC NORSRAM interface function FMC_NORSRAM_Timing_Init() (##) Extended mode Timing register configuration using the FMC NORSRAM interface function FMC_NORSRAM_Extended_Timing_Init() (##) Enable the SRAM device using the macro __FMC_NORSRAM_ENABLE() (#) At this stage you can perform read/write accesses from/to the memory connected to the NOR/SRAM Bank. You can perform either polling or DMA transfer using the following APIs: (++) HAL_SRAM_Read()/HAL_SRAM_Write() for polling read/write access (++) HAL_SRAM_Read_DMA()/HAL_SRAM_Write_DMA() for DMA read/write transfer (#) You can also control the SRAM device by calling the control APIs HAL_SRAM_WriteOperation_Enable()/ HAL_SRAM_WriteOperation_Disable() to respectively enable/disable the SRAM write operation (#) You can continuously monitor the SRAM device HAL state by calling the function HAL_SRAM_GetState() *** Callback registration *** ============================================= [..] The compilation define USE_HAL_SRAM_REGISTER_CALLBACKS when set to 1 allows the user to configure dynamically the driver callbacks. Use Functions HAL_SRAM_RegisterCallback() to register a user callback, it allows to register following callbacks: (+) MspInitCallback : SRAM MspInit. (+) MspDeInitCallback : SRAM MspDeInit. This function takes as parameters the HAL peripheral handle, the Callback ID and a pointer to the user callback function. Use function HAL_SRAM_UnRegisterCallback() to reset a callback to the default weak (overridden) function. It allows to reset following callbacks: (+) MspInitCallback : SRAM MspInit. (+) MspDeInitCallback : SRAM MspDeInit. This function) takes as parameters the HAL peripheral handle and the Callback ID. By default, after the HAL_SRAM_Init and if the state is HAL_SRAM_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_SRAM_Init and HAL_SRAM_DeInit only when these callbacks are null (not registered beforehand). If not, MspInit or MspDeInit are not null, the HAL_SRAM_Init and HAL_SRAM_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_SRAM_RegisterCallback before calling HAL_SRAM_DeInit or HAL_SRAM_Init function. When The compilation define USE_HAL_SRAM_REGISTER_CALLBACKS is set to 0 or not defined, the callback registering feature is not available and weak (overridden) callbacks are used.