kopia lustrzana https://github.com/espressif/esp-idf
Merge branch 'docs/add_Chinese_translation_for_api-reference/peripherals/sdmmc_host.rst' into 'master'
docs: provide CN translation for api-reference/peripherals/sdmmc_host.rst Closes DOC-6083 See merge request espressif/esp-idf!25563pull/12330/head
Cai Xin Ying
commit
5518b16b52
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@ -1,10 +1,12 @@
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SDMMC Host Driver
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=================
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:link_to_translation:`zh_CN:[中文]`
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Overview
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--------
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{IDF_TARGET_NAME}'s SDMMC host peripheral has two slots. Each slot can be used independently to connect to an SD card, SDIO device or eMMC chip.
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{IDF_TARGET_NAME}'s SDMMC host peripheral has two slots. Each slot can be used independently to connect to an SD card, SDIO device, or eMMC chip.
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.. only:: esp32
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@ -13,44 +15,61 @@ Overview
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The slots are connected to {IDF_TARGET_NAME} GPIOs using IO MUX. Pin mappings of these slots are given in the table below.
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+--------+-------------+-------------+
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| Signal | Slot 0 | Slot 1 |
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+========+=============+=============+
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| CMD | GPIO11 | GPIO15 |
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+--------+-------------+-------------+
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| CLK | GPIO6 | GPIO14 |
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+--------+-------------+-------------+
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| D0 | GPIO7 | GPIO2 |
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+--------+-------------+-------------+
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| D1 | GPIO8 | GPIO4 |
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+--------+-------------+-------------+
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| D2 | GPIO9 | GPIO12 |
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+--------+-------------+-------------+
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| D3 | GPIO10 | GPIO13 |
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+--------+-------------+-------------+
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| D4 | GPIO16 | |
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+--------+-------------+-------------+
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| D5 | GPIO17 | |
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+--------+-------------+-------------+
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| D6 | GPIO5 | |
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+--------+-------------+-------------+
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| D7 | GPIO18 | |
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+--------+-------------+-------------+
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| CD | any input via GPIO matrix |
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+--------+---------------------------+
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| WP | any input via GPIO matrix |
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+--------+---------------------------+
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.. list-table::
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:header-rows: 1
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:widths: 20 40 40
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:align: center
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The Card Detect and Write Protect signals can be routed to arbitrary pins using the GPIO matrix. To reserve the pins, set the ``cd`` and ``wp`` members of the :cpp:class:`sdmmc_slot_config_t` structure before calling :cpp:func:`sdmmc_host_init_slot`. Please note that it is not advised to specify a Card Detect pin when working with SDIO cards, because the card detect signal in ESP32 can also trigger SDIO slave interrupt.
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* - Signal
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- Slot 0
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- Slot 1
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* - CMD
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- GPIO11
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- GPIO15
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* - CLK
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- GPIO6
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- GPIO14
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* - D0
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- GPIO7
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- GPIO2
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* - D1
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- GPIO8
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- GPIO4
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* - D2
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- GPIO9
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- GPIO12
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* - D3
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- GPIO10
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- GPIO13
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* - D4
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- GPIO16
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-
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* - D5
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- GPIO17
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-
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* - D6
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- GPIO5
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-
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* - D7
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- GPIO18
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-
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* - CD
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- any input via GPIO matrix
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- any input via GPIO matrix
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* - WP
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- any input via GPIO matrix
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- any input via GPIO matrix
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The Card Detect (CD) and Write Protect (WP) signals can be routed to arbitrary pins using the GPIO matrix. To reserve the pins, set the ``cd`` and ``wp`` members of the :cpp:class:`sdmmc_slot_config_t` structure before calling :cpp:func:`sdmmc_host_init_slot`. Please note that it is not advised to specify a CD pin when working with SDIO cards, because the CD signal in ESP32 can also trigger SDIO slave interrupt.
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.. warning::
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Pins used by Slot 0 (``HS1_*``) are also used to connect the SPI flash chip in ESP32-WROOM and ESP32-WROVER modules. These pins cannot be shared between an SD card and SPI flash. If you need to use Slot 0, connect SPI flash to different pins and set eFuses accordingly.
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Pins used by Slot 0 (``HS1_*``) are also used to connect the SPI flash chip in ESP32-WROOM and ESP32-WROVER modules. These pins cannot be concurrently shared between an SD card and an SPI flash. If you need to use Slot 0, establish an alternative connection for the SPI flash using different pins and configure the necessary eFuses accordingly.
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.. only:: SOC_SDMMC_USE_GPIO_MATRIX
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Both slots (:c:macro:`SDMMC_HOST_SLOT_0`, :c:macro:`SDMMC_HOST_SLOT_1`) support 1-, 4- and 8-line SD interface. The slots are connected to {IDF_TARGET_NAME} GPIOs using GPIO matrix. This means that any GPIO may be used for each of the SD card signals.
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Both slots :c:macro:`SDMMC_HOST_SLOT_0` and :c:macro:`SDMMC_HOST_SLOT_1` support 1-, 4- and 8-line SD interfaces. The slots are connected to {IDF_TARGET_NAME} GPIOs using the GPIO matrix. This means that any GPIO may be used for each of the SD card signals.
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Supported Speed Modes
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@ -58,14 +77,14 @@ Supported Speed Modes
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SDMMC Host driver supports the following speed modes:
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- Default Speed (20 MHz), 1-line or 4-line (with SD cards), and 1-line, 4-line or 8-line (with 3.3 V eMMC)
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- High Speed (40 MHz), 1-line or 4-line (with SD cards), and 1-line, 4-line or 8-line (with 3.3 V eMMC)
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- High Speed DDR (40 MHz), 4-line (with 3.3 V eMMC)
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- Default Speed (20 MHz): 1-line or 4-line with SD cards, and 1-line, 4-line, or 8-line with 3.3 V eMMC
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- High Speed (40 MHz): 1-line or 4-line with SD cards, and 1-line, 4-line, or 8-line with 3.3 V eMMC
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- High Speed DDR (40 MHz): 4-line with 3.3 V eMMC
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Speed modes not supported at present:
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- High Speed DDR mode, 8-line eMMC
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- UHS-I 1.8 V modes, 4-line SD cards
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- High Speed DDR mode: 8-line eMMC
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- UHS-I 1.8 V modes: 4-line SD cards
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Using the SDMMC Host Driver
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@ -87,17 +106,22 @@ Other functions, such as the ones given below, will be called by the SD/MMC prot
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Configuring Bus Width and Frequency
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-----------------------------------
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With the default initializers for :cpp:class:`sdmmc_host_t` and :cpp:class:`sdmmc_slot_config_t` (:c:macro:`SDMMC_HOST_DEFAULT` and :c:macro:`SDMMC_SLOT_CONFIG_DEFAULT`), SDMMC Host driver will attempt to use the widest bus supported by the card (4 lines for SD, 8 lines for eMMC) and the frequency of 20 MHz.
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With the default initializers for :cpp:class:`sdmmc_host_t` and :cpp:class:`sdmmc_slot_config_t`, i.e., :c:macro:`SDMMC_HOST_DEFAULT` and :c:macro:`SDMMC_SLOT_CONFIG_DEFAULT`, SDMMC Host driver will attempt to use the widest bus supported by the card (4 lines for SD, 8 lines for eMMC) and the frequency of 20 MHz.
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In the designs where communication at 40 MHz frequency can be achieved, it is possible to increase the bus frequency by changing the ``max_freq_khz`` field of :cpp:class:`sdmmc_host_t`::
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In the designs where communication at 40 MHz frequency can be achieved, it is possible to increase the bus frequency by changing the ``max_freq_khz`` field of :cpp:class:`sdmmc_host_t`:
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.. code-block::
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sdmmc_host_t host = SDMMC_HOST_DEFAULT();
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host.max_freq_khz = SDMMC_FREQ_HIGHSPEED;
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If you need a specific frequency other than standard speeds, you are free to use any value from within appropriate range of the SD interface given (SDMMC or SDSPI). However, the real clock frequency shall be calculated by the underlying driver and the value can be different from the one required.
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For the SDMMC, ``max_freq_khz`` works as the upper limit so the final frequency value shall be always lower or equal. For the SDSPI, the nearest fitting frequency is supplied and thus the value can be greater than / equal to / lower than ``max_freq_khz``.
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If you need a specific frequency other than standard speeds, you are free to use any value from within an appropriate range of the SD interface given (SDMMC or SDSPI). However, the real clock frequency shall be calculated by the underlying driver and the value can be different from the one required.
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To configure the bus width, set the ``width`` field of :cpp:class:`sdmmc_slot_config_t`. For example, to set 1-line mode::
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For the SDMMC, ``max_freq_khz`` works as the upper limit so the final frequency value shall be always lower or equal. For the SDSPI, the nearest fitting frequency is supplied and thus the value can be greater than/equal to/lower than ``max_freq_khz``.
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To configure the bus width, set the ``width`` field of :cpp:class:`sdmmc_slot_config_t`. For example, to set 1-line mode:
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.. code-block::
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sdmmc_slot_config_t slot = SDMMC_SLOT_CONFIG_DEFAULT();
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slot.width = 1;
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@ -107,7 +131,11 @@ To configure the bus width, set the ``width`` field of :cpp:class:`sdmmc_slot_co
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Configuring GPIOs
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-----------------
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{IDF_TARGET_NAME} SDMMC Host can be configured to use arbitrary GPIOs for each of the signals. Configuration is performed by setting members of :cpp:class:`sdmmc_slot_config_t` structure. For example, to use GPIOs 1-6 for CLK, CMD, D0 - D3 signals, respectively::
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{IDF_TARGET_NAME} SDMMC Host can be configured to use arbitrary GPIOs for each of the signals. Configuration is performed by setting members of :cpp:class:`sdmmc_slot_config_t` structure.
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For example, to use GPIOs 1-6 for CLK, CMD, and D0-D3 signals respectively:
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.. code-block::
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sdmmc_slot_config_t slot = SDMMC_SLOT_CONFIG_DEFAULT();
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slot.clk = GPIO_NUM_1;
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@ -117,16 +145,18 @@ To configure the bus width, set the ``width`` field of :cpp:class:`sdmmc_slot_co
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slot.d2 = GPIO_NUM_5;
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slot.d3 = GPIO_NUM_6;
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It is also possible to configure Card Detect and Write Protect pins. Similar to other signals, set ``cd`` and ``wp`` members of the same structure::
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It is also possible to configure Card Detect and Write Protect pins. Similar to other signals, set ``cd`` and ``wp`` members of the same structure:
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.. code-block::
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slot.cd = GPIO_NUM_7;
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slot.wp = GPIO_NUM_8;
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``SDMMC_SLOT_CONFIG_DEFAULT`` sets both to ``GPIO_NUM_NC``, meaning that by default the signals are not used.
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Once :cpp:class:`sdmmc_slot_config_t` structure is initialized this way, you can use it when calling :cpp:func:`sdmmc_host_init_slot` or one of the higher level functions, such as :cpp:func:`esp_vfs_fat_sdmmc_mount`.
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Once :cpp:class:`sdmmc_slot_config_t` structure is initialized this way, you can use it when calling :cpp:func:`sdmmc_host_init_slot` or one of the higher level functions (such as :cpp:func:`esp_vfs_fat_sdmmc_mount`).
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DDR Mode for eMMC chips
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DDR Mode for eMMC Chips
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-----------------------
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By default, DDR mode will be used if:
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@ -134,7 +164,9 @@ By default, DDR mode will be used if:
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- SDMMC host frequency is set to :c:macro:`SDMMC_FREQ_HIGHSPEED` in :cpp:class:`sdmmc_host_t` structure, and
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- eMMC chip reports DDR mode support in its CSD register
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DDR mode places higher requirements for signal integrity. To disable DDR mode while keeping :c:macro:`SDMMC_FREQ_HIGHSPEED` frequency, clear :c:macro:`SDMMC_HOST_FLAG_DDR` bit in ``flags`` field of :cpp:class:`sdmmc_host_t`::
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DDR mode places higher requirements for signal integrity. To disable DDR mode while keeping the :c:macro:`SDMMC_FREQ_HIGHSPEED` frequency, clear the :c:macro:`SDMMC_HOST_FLAG_DDR` bit in :cpp:member:`sdmmc_host_t::flags` field of the :cpp:class:`sdmmc_host_t`:
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.. code-block::
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sdmmc_host_t host = SDMMC_HOST_DEFAULT();
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host.max_freq_khz = SDMMC_FREQ_HIGHSPEED;
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@ -144,11 +176,9 @@ DDR mode places higher requirements for signal integrity. To disable DDR mode wh
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See also
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--------
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See :doc:`SD/SDIO/MMC Driver <../storage/sdmmc>` for the higher level driver which implements the protocol layer.
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See :doc:`SD SPI Host Driver <sdspi_host>` for a similar driver which uses the SPI controller and is limited to SD protocol's SPI mode.
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See :doc:`sd_pullup_requirements` for pullup support and compatibilities of modules and development kits.
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- :doc:`../storage/sdmmc`: introduces the higher-level driver which implements the protocol layer.
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- :doc:`sdspi_host`: introduces a similar driver that uses the SPI controller and is limited to SD protocol's SPI mode.
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- :doc:`sd_pullup_requirements`: introduces pull-up support and compatibilities of modules and development kits.
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API Reference
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|
|
|
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|
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@ -1 +1,187 @@
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.. include:: ../../../en/api-reference/peripherals/sdmmc_host.rst
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SDMMC 主机驱动
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=================
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|
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:link_to_translation:`en:[English]`
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|
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概述
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--------
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{IDF_TARGET_NAME} 的 SDMMC 主机外设共有两个卡槽，用于插入 SD 卡、连接 SDIO 设备或连接 eMMC 芯片，每个卡槽均可单独使用。
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.. only:: esp32
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|
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- 卡槽 0 (:c:macro:`SDMMC_HOST_SLOT_0`) 为 8 位卡槽，使用 PIN MUX 中的 ``HS1_*`` 信号。
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- 卡槽 1 (:c:macro:`SDMMC_HOST_SLOT_1`) 为 4 位卡槽，使用 PIN MUX 中的 ``HS2_*`` 信号。
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这些卡槽通过 IO MUX 连接到 {IDF_TARGET_NAME} 的 GPIO，其管脚映射如下表所示。
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.. list-table::
|
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:header-rows: 1
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:widths: 20 40 40
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:align: center
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* - 信号
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- 卡槽 0
|
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- 卡槽 1
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* - CMD
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- GPIO11
|
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- GPIO15
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* - CLK
|
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- GPIO6
|
||||
- GPIO14
|
||||
* - D0
|
||||
- GPIO7
|
||||
- GPIO2
|
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* - D1
|
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- GPIO8
|
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- GPIO4
|
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* - D2
|
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- GPIO9
|
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- GPIO12
|
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* - D3
|
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- GPIO10
|
||||
- GPIO13
|
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* - D4
|
||||
- GPIO16
|
||||
-
|
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* - D5
|
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- GPIO17
|
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-
|
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* - D6
|
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- GPIO5
|
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-
|
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* - D7
|
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- GPIO18
|
||||
-
|
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* - CD
|
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- 来自 GPIO 交换矩阵的任意输入
|
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- 来自 GPIO 交换矩阵的任意输入
|
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* - WP
|
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- 来自 GPIO 交换矩阵的任意输入
|
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- 来自 GPIO 交换矩阵的任意输入
|
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|
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可以通过 GPIO 交换矩阵将卡检测 (CD) 和写保护 (WP) 信号路由到任意管脚。为了保留这些管脚，需要先配置 :cpp:class:`sdmmc_slot_config_t` 结构体的 ``cd`` 和 ``wp``，再调用 :cpp:func:`sdmmc_host_init_slot`。注意，使用 SDIO 卡时，不建议指定 CD 管脚，因为 ESP32 中的 CD 信号也可能触发 SDIO 从机设备中断。
|
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|
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.. warning::
|
||||
|
||||
卡槽 0 使用的管脚 (``HS1_*``) 既用于连接主机上的 SD 卡插槽，也用于连接 ESP32-WROOM 和 ESP32-WROVER 模组中的 SPI flash 芯片，但这些管脚不能同时用于 SD 卡与 SPI flash。如需使用卡槽 0，请将 SPI flash 连接到其他管脚，并根据需要配置 eFuse。
|
||||
|
||||
|
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.. only:: SOC_SDMMC_USE_GPIO_MATRIX
|
||||
|
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卡槽 :c:macro:`SDMMC_HOST_SLOT_0` 和 :c:macro:`SDMMC_HOST_SLOT_1` 都支持 1、4、8 线的 SD 接口，这些卡槽通过 GPIO 交换矩阵连接到 {IDF_TARGET_NAME} 的 GPIO，即每个 SD 卡信号都可以使用任意 GPIO 连接。
|
||||
|
||||
|
||||
支持的速率模式
|
||||
---------------------
|
||||
|
||||
SDMMC 主机驱动支持以下速率模式：
|
||||
|
||||
- 默认速率 (20 MHz)：对于 SD 卡，支持 1 线或 4 线传输；对于 3.3 V eMMC，支持 1 线、4 线或 8 线传输。
|
||||
- 高速模式 (40 MHz)：对于 SD 卡，支持 1 线或 4 线传输；对于 3.3 V eMMC，支持 1 线、4 线或 8 线传输。
|
||||
- 高速 DDR 模式 (40 MHz)：对于 3.3 V eMMC，支持 4 线传输。
|
||||
|
||||
当前尚不支持的速率模式：
|
||||
|
||||
- 高速 DDR 模式：不支持 8 线 eMMC 传输
|
||||
- UHS-I 1.8 V 模式：不支持 4 线 SD 卡传输
|
||||
|
||||
|
||||
使用 SDMMC 主机驱动
|
||||
---------------------------
|
||||
|
||||
在大多数应用程序中，只有下列函数会被直接调用：
|
||||
|
||||
- :cpp:func:`sdmmc_host_init`
|
||||
- :cpp:func:`sdmmc_host_init_slot`
|
||||
- :cpp:func:`sdmmc_host_deinit`
|
||||
|
||||
其他函数将通过 :cpp:class:`sdmmc_host_t` 结构体中的函数指针由 SD/MMC 协议层调用，例如：
|
||||
|
||||
- :cpp:func:`sdmmc_host_set_bus_width`
|
||||
- :cpp:func:`sdmmc_host_set_card_clk`
|
||||
- :cpp:func:`sdmmc_host_do_transaction`
|
||||
|
||||
|
||||
配置总线宽度和频率
|
||||
-----------------------------------
|
||||
|
||||
使用 :cpp:class:`sdmmc_host_t` 和 :cpp:class:`sdmmc_slot_config_t` 的默认初始化配置，即 :c:macro:`SDMMC_HOST_DEFAULT` 和 :c:macro:`SDMMC_SLOT_CONFIG_DEFAULT` 时，SDMMC 主机驱动会尝试以当前卡所支持的最大总线宽度进行通信（SD 卡为 4 线，eMMC 为 8 线），并使用 20 MHz 的通信频率。
|
||||
|
||||
在支持 40 MHz 频率通信的设计中，可以调整 :cpp:class:`sdmmc_host_t` 结构体中的 ``max_freq_khz`` 字段，提升总线频率：
|
||||
|
||||
.. code-block::
|
||||
|
||||
sdmmc_host_t host = SDMMC_HOST_DEFAULT();
|
||||
host.max_freq_khz = SDMMC_FREQ_HIGHSPEED;
|
||||
|
||||
如需选择标准速率以外的特定频率，请根据所使用的 SD 接口（SDMMC 或 SDSPI）确定适当频率范围，并选择其中的任意值。然而，实际的时钟频率会由底层驱动程序计算，可能与你所需的值不同。
|
||||
|
||||
使用 SDMMC 接口时，``max_freq_khz`` 即频率上限，因此最终的频率值应始终低于该上限。而使用 SDSPI 接口时，驱动程序会提供最接近的适配频率，因此该值可以大于、等于或小于 ``max_freq_khz``。
|
||||
|
||||
请配置 :cpp:class:`sdmmc_slot_config_t` 的 ``width`` 字段，配置总线宽度。例如，配置 1 线模式的代码如下：
|
||||
|
||||
.. code-block::
|
||||
|
||||
sdmmc_slot_config_t slot = SDMMC_SLOT_CONFIG_DEFAULT();
|
||||
slot.width = 1;
|
||||
|
||||
.. only:: SOC_SDMMC_USE_GPIO_MATRIX
|
||||
|
||||
配置 GPIO
|
||||
-----------------
|
||||
|
||||
通过配置结构体 :cpp:class:`sdmmc_slot_config_t`，{IDF_TARGET_NAME} 的 SDMMC 主机可以根据需要，为每个信号配置任意的 GPIO 管脚。
|
||||
|
||||
例如，使用以下代码，可以将 GPIO 1-6 分别用于 CLK、CMD、D0-D3 信号：
|
||||
|
||||
.. code-block::
|
||||
|
||||
sdmmc_slot_config_t slot = SDMMC_SLOT_CONFIG_DEFAULT();
|
||||
slot.clk = GPIO_NUM_1;
|
||||
slot.cmd = GPIO_NUM_2;
|
||||
slot.d0 = GPIO_NUM_3;
|
||||
slot.d1 = GPIO_NUM_4;
|
||||
slot.d2 = GPIO_NUM_5;
|
||||
slot.d3 = GPIO_NUM_6;
|
||||
|
||||
也可以配置 CD 和 WP 管脚。与配置其他信号的方法类似，你只需配置相同结构体的 ``cd`` 和 ``wp`` 参数：
|
||||
|
||||
.. code-block::
|
||||
|
||||
slot.cd = GPIO_NUM_7;
|
||||
slot.wp = GPIO_NUM_8;
|
||||
|
||||
``SDMMC_SLOT_CONFIG_DEFAULT`` 将 CD 和 WP 管脚都配置为 ``GPIO_NUM_NC``，表明默认情况下不会使用这两个管脚。
|
||||
|
||||
通过上述方式初始化 :cpp:class:`sdmmc_slot_config_t` 结构体后，即可在调用 :cpp:func:`sdmmc_host_init_slot` 或其他任意高层函数（如 :cpp:func:`esp_vfs_fat_sdmmc_mount`）时使用该结构体。
|
||||
|
||||
eMMC 芯片的 DDR 模式
|
||||
-----------------------
|
||||
|
||||
默认情况下，如果满足以下条件，将使用 DDR 模式：
|
||||
|
||||
- 在 :cpp:class:`sdmmc_host_t` 结构体中将 SDMMC 主机频率配置为 :c:macro:`SDMMC_FREQ_HIGHSPEED`，且
|
||||
- eMMC 芯片在其 CSD 寄存器中报告支持 DDR 模式
|
||||
|
||||
DDR 模式对信号完整性要求更高。如果要在保持 :c:macro:`SDMMC_FREQ_HIGHSPEED` 频率的同时禁用 DDR 模式，请在 :cpp:class:`sdmmc_host_t` 结构体的 :cpp:member:`sdmmc_host_t::flags` 字段中清除 :c:macro:`SDMMC_HOST_FLAG_DDR` 位：
|
||||
|
||||
.. code-block::
|
||||
|
||||
sdmmc_host_t host = SDMMC_HOST_DEFAULT();
|
||||
host.max_freq_khz = SDMMC_FREQ_HIGHSPEED;
|
||||
host.flags &= ~SDMMC_HOST_FLAG_DDR;
|
||||
|
||||
|
||||
相关文档
|
||||
--------
|
||||
|
||||
- :doc:`../storage/sdmmc`：介绍了实现协议层的高层驱动程序。
|
||||
- :doc:`sdspi_host`：介绍了一种类似驱动，该驱动使用 SPI 控制器且受限于 SD 协议的 SPI 模式。
|
||||
- :doc:`sd_pullup_requirements` 介绍了模组和开发套件上的上拉支持和兼容信息。
|
||||
|
||||
|
||||
API 参考
|
||||
-------------
|
||||
|
||||
.. include-build-file:: inc/sdmmc_host.inc
|
||||
|
|
|
|||
Ładowanie…
Reference in New Issue