SPI 代码¶

组件架构¶

- driver
    - spi
        - include
            - spi.h
        - spi.c
        - CMakeLists.txt

driver/spi/CMakeLists.txt¶

set(src_dirs
    .
)

set(include_dirs
    include
)

set(requires
    driver
)

idf_component_register(SRC_DIRS ${src_dirs} INCLUDE_DIRS ${include_dirs} REQUIRES ${requires})

Note

注意，在驱动程序中，我们使用了 ESP-IDF 内置的 driver 库中的spi和gpio相关函数，因此，我们需要在 CMakeLists.txt 文件的 REQUIRES 字段中指明这个依赖关系。

spi.h¶

/**
 * @file spi.h
 * @author SHUAIWEN CUI (SHUAIWEN001@e.ntu.edu.sg)
 * @brief
 * @version 1.0
 * @date 2024-11-18
 * @ref Alientek SPI driver
 * @copyright Copyright (c) 2024
 *
 */

#pragma once

#ifdef __cplusplus
extern "C"
{
#endif

/* Dependencies */
#include <string.h>
#include "esp_log.h"
#include "driver/spi_master.h"
#include "driver/gpio.h"

/* GPIO Definitions */
#define SPI2_MOSI_GPIO_PIN GPIO_NUM_11 /* SPI2_MOSI */
#define SPI2_CLK_GPIO_PIN GPIO_NUM_12  /* SPI2_CLK */
#define SPI2_MISO_GPIO_PIN GPIO_NUM_13 /* SPI2_MISO */

    /* Function Prototypes */

    /**
     * @brief       Initialize SPI
     * @param       None
     * @retval      None
     */
    void spi2_init(void);

    /**
     * @brief       Send command via SPI
     * @param       handle : SPI handle
     * @param       cmd    : Command to send
     * @retval      None
     */
    void spi2_write_cmd(spi_device_handle_t handle, uint8_t cmd);

    /**
     * @brief       Send data via SPI
     * @param       handle : SPI handle
     * @param       data   : Data to send
     * @param       len    : Length of data to send
     * @retval      None
     */
    void spi2_write_data(spi_device_handle_t handle, const uint8_t *data, int len);

    /**
     * @brief       Process data via SPI
     * @param       handle       : SPI handle
     * @param       data         : Data to send
     * @retval      t.rx_data[0] : Received data
     */
    uint8_t spi2_transfer_byte(spi_device_handle_t handle, uint8_t byte);

#ifdef __cplusplus
}
#endif

spi.c¶

/**
 * @file spi.c
 * @author
 * @brief
 * @version 1.0
 * @date 2024-11-18
 * @ref Alientek SPI driver
 *
 */

#include "spi.h"

#ifdef __cplusplus
extern "C"
{
#endif

    /**
     * @brief       Initialize SPI
     * @param       None
     * @retval      None
     */
    void spi2_init(void)
    {
        esp_err_t ret = 0;
        spi_bus_config_t spi_bus_conf = {0};

        /* SPI bus configuration */
        spi_bus_conf.miso_io_num = SPI2_MISO_GPIO_PIN; /* SPI_MISO pin */
        spi_bus_conf.mosi_io_num = SPI2_MOSI_GPIO_PIN; /* SPI_MOSI pin */
        spi_bus_conf.sclk_io_num = SPI2_CLK_GPIO_PIN;  /* SPI_SCLK pin */
        spi_bus_conf.quadwp_io_num = -1;               /* SPI write protection signal pin, not enabled */
        spi_bus_conf.quadhd_io_num = -1;               /* SPI hold signal pin, not enabled */
        spi_bus_conf.max_transfer_sz = 160 * 80 * 2;   /* Configure maximum transfer size in bytes */

        /* Initialize SPI bus */
        ret = spi_bus_initialize(SPI2_HOST, &spi_bus_conf, SPI_DMA_CH_AUTO); /* SPI bus initialization */
        ESP_ERROR_CHECK(ret);                                                /* Check parameter values */
    }

    /**
     * @brief       Send command via SPI
     * @param       handle : SPI handle
     * @param       cmd    : Command to send
     * @retval      None
     */
    void spi2_write_cmd(spi_device_handle_t handle, uint8_t cmd)
    {
        esp_err_t ret;
        spi_transaction_t t = {0};

        t.length = 8;                                  /* Number of bits to transmit (1 byte = 8 bits) */
        t.tx_buffer = &cmd;                            /* Fill the command */
        ret = spi_device_polling_transmit(handle, &t); /* Start transmission */
        ESP_ERROR_CHECK(ret);                          /* Usually no issues */
    }

    /**
     * @brief       Send data via SPI
     * @param       handle : SPI handle
     * @param       data   : Data to send
     * @param       len    : Length of data to send
     * @retval      None
     */
    void spi2_write_data(spi_device_handle_t handle, const uint8_t *data, int len)
    {
        esp_err_t ret;
        spi_transaction_t t = {0};

        if (len == 0)
        {
            return; /* No data to transmit if length is 0 */
        }

        t.length = len * 8;                            /* Number of bits to transmit (1 byte = 8 bits) */
        t.tx_buffer = data;                            /* Fill the data */
        ret = spi_device_polling_transmit(handle, &t); /* Start transmission */
        ESP_ERROR_CHECK(ret);                          /* Usually no issues */
    }

    /**
     * @brief       Process data via SPI
     * @param       handle       : SPI handle
     * @param       data         : Data to send
     * @retval      t.rx_data[0] : Received data
     */
    uint8_t spi2_transfer_byte(spi_device_handle_t handle, uint8_t data)
    {
        spi_transaction_t t;

        memset(&t, 0, sizeof(t));

        t.flags = SPI_TRANS_USE_TXDATA | SPI_TRANS_USE_RXDATA;
        t.length = 8;
        t.tx_data[0] = data;
        spi_device_transmit(handle, &t);

        return t.rx_data[0];
    }

#ifdef __cplusplus
}
#endif

main.c¶

refer to LCD code

注意

以上是在 ESP32-S3 上设置 SPI2 的代码。如果使用其他SPI外设，则需要相应配置相应的引脚和SPI主机。例如，我们以后的SD卡将使用SPI3，则需要相应配置引脚和SPI主机。