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STM32F4xx HAL Driver master
STM32CubeF4 HAL / LL Drivers API Reference
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SDMMC Low Layer HAL module driver. More...
#include "stm32f4xx_hal.h"Go to the source code of this file.
SDMMC Low Layer HAL module driver.
Copyright (c) 2016 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.
==============================================================================
##### SDMMC peripheral features #####
==============================================================================
[..] The SD/SDMMC MMC card host interface (SDMMC) provides an interface between the AHB
peripheral bus and MultiMedia cards (MMCs), SD memory cards, SDMMC cards and CE-ATA
devices.
[..] The SDMMC features include the following:
(+) Full compliance with MultiMedia Card System Specification Version 4.2. Card support
for three different databus modes: 1-bit (default), 4-bit and 8-bit
(+) Full compatibility with previous versions of MultiMedia Cards (forward compatibility)
(+) Full compliance with SD Memory Card Specifications Version 2.0
(+) Full compliance with SD I/O Card Specification Version 2.0: card support for two
different data bus modes: 1-bit (default) and 4-bit
(+) Full support of the CE-ATA features (full compliance with CE-ATA digital protocol
Rev1.1)
(+) Data transfer up to 48 MHz for the 8 bit mode
(+) Data and command output enable signals to control external bidirectional drivers
##### How to use this driver #####
==============================================================================
[..]
This driver is a considered as a driver of service for external devices drivers
that interfaces with the SDMMC peripheral.
According to the device used (SD card/ MMC card / SDMMC card ...), a set of APIs
is used in the device's driver to perform SDMMC operations and functionalities.
This driver is almost transparent for the final user, it is only used to implement other
functionalities of the external device.
[..]
(+) The SDMMC clock (SDMMCCLK = 48 MHz) is coming from a specific output (MSI, PLLUSB1CLK,
PLLUSB2CLK). Before start working with SDMMC peripheral make sure that the
PLL is well configured.
The SDMMC peripheral uses two clock signals:
(++) SDMMC adapter clock (SDMMCCLK = 48 MHz)
(++) APB2 bus clock (PCLK2)
-@@- PCLK2 and SDMMC_CK clock frequencies must respect the following condition:
Frequency(PCLK2) >= (3 / 8 x Frequency(SDMMC_CK))
(+) Enable/Disable peripheral clock using RCC peripheral macros related to SDMMC
peripheral.
(+) Enable the Power ON State using the SDIO_PowerState_ON()
function and disable it using the function SDIO_PowerState_OFF().
(+) Enable/Disable the clock using the __SDIO_ENABLE()/__SDIO_DISABLE() macros.
(+) Enable/Disable the peripheral interrupts using the macros __SDIO_ENABLE_IT()
and __SDIO_DISABLE_IT() if you need to use interrupt mode.
(+) When using the DMA mode
(++) Configure the DMA in the MSP layer of the external device
(++) Active the needed channel Request
(++) Enable the DMA using __SDIO_DMA_ENABLE() macro or Disable it using the macro
__SDIO_DMA_DISABLE().
(+) To control the CPSM (Command Path State Machine) and send
commands to the card use the SDIO_SendCommand(),
SDIO_GetCommandResponse() and SDIO_GetResponse() functions. First, user has
to fill the command structure (pointer to SDIO_CmdInitTypeDef) according
to the selected command to be sent.
The parameters that should be filled are:
(++) Command Argument
(++) Command Index
(++) Command Response type
(++) Command Wait
(++) CPSM Status (Enable or Disable).
-@@- To check if the command is well received, read the SDIO_CMDRESP
register using the SDIO_GetCommandResponse().
The SDMMC responses registers (SDIO_RESP1 to SDIO_RESP2), use the
SDIO_GetResponse() function.
(+) To control the DPSM (Data Path State Machine) and send/receive
data to/from the card use the SDIO_DataConfig(), SDIO_GetDataCounter(),
SDIO_ReadFIFO(), SDIO_WriteFIFO() and SDIO_GetFIFOCount() functions.
*** Read Operations ***
=======================
[..]
(#) First, user has to fill the data structure (pointer to
SDIO_DataInitTypeDef) according to the selected data type to be received.
The parameters that should be filled are:
(++) Data TimeOut
(++) Data Length
(++) Data Block size
(++) Data Transfer direction: should be from card (To SDMMC)
(++) Data Transfer mode
(++) DPSM Status (Enable or Disable)
(#) Configure the SDMMC resources to receive the data from the card
according to selected transfer mode (Refer to Step 8, 9 and 10).
(#) Send the selected Read command (refer to step 11).
(#) Use the SDIO flags/interrupts to check the transfer status.
*** Write Operations ***
========================
[..]
(#) First, user has to fill the data structure (pointer to
SDIO_DataInitTypeDef) according to the selected data type to be received.
The parameters that should be filled are:
(++) Data TimeOut
(++) Data Length
(++) Data Block size
(++) Data Transfer direction: should be to card (To CARD)
(++) Data Transfer mode
(++) DPSM Status (Enable or Disable)
(#) Configure the SDMMC resources to send the data to the card according to
selected transfer mode.
(#) Send the selected Write command.
(#) Use the SDIO flags/interrupts to check the transfer status.
*** Command management operations ***
=====================================
[..]
(#) The commands used for Read/Write/Erase operations are managed in
separate functions.
Each function allows to send the needed command with the related argument,
then check the response.
By the same approach, you could implement a command and check the response.
Definition in file stm32f4xx_ll_sdmmc.c.
1.16.1