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
 *
 */

#ifndef __SPI_H__
#define __SPI_H__

/* 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);

#endif

spi.c¶

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

 #include "spi.h"

 /**
  * @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];
 }

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。