基于esp-idf 帮我写一个iic代码

好的，以下是一个简单的 ESP-IDF I2C 代码：

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/i2c.h"

#define I2C_MASTER_SCL_IO 22               /*!< gpio number for I2C master clock */
#define I2C_MASTER_SDA_IO 21               /*!< gpio number for I2C master data  */
#define I2C_MASTER_NUM I2C_NUM_0           /*!< I2C port number for master dev */
#define I2C_MASTER_FREQ_HZ 100000          /*!< I2C master clock frequency */
#define I2C_MASTER_TX_BUF_DISABLE 0        /*!< I2C master doesn't need buffer */
#define I2C_MASTER_RX_BUF_DISABLE 0        /*!< I2C master doesn't need buffer */

static void i2c_master_init()
{
    int i2c_master_port = I2C_MASTER_NUM;
    i2c_config_t conf;
    conf.mode = I2C_MODE_MASTER;
    conf.sda_io_num = I2C_MASTER_SDA_IO;
    conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
    conf.scl_io_num = I2C_MASTER_SCL_IO;
    conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
    conf.master.clk_speed = I2C_MASTER_FREQ_HZ;
    i2c_param_config(i2c_master_port, &conf);
    i2c_driver_install(i2c_master_port, conf.mode, I2C_MASTER_TX_BUF_DISABLE, I2C_MASTER_RX_BUF_DISABLE, 0);
}

void i2c_master_write_slave(uint8_t address, uint8_t reg, uint8_t data)
{
    i2c_cmd_handle_t cmd = i2c_cmd_link_create();
    i2c_master_start(cmd);
    i2c_master_write_byte(cmd, (address << 1) | I2C_MASTER_WRITE, true);
    i2c_master_write_byte(cmd, reg, true);
    i2c_master_write_byte(cmd, data, true);
    i2c_master_stop(cmd);
    i2c_master_cmd_begin(I2C_MASTER_NUM, cmd, 1000 / portTICK_RATE_MS);
    i2c_cmd_link_delete(cmd);
}

void i2c_master_read_slave(uint8_t address, uint8_t reg, uint8_t *data, size_t size)
{
    i2c_cmd_handle_t cmd = i2c_cmd_link_create();
    i2c_master_start(cmd);
    i2c_master_write_byte(cmd, (address << 1) | I2C_MASTER_WRITE, true);
    i2c_master_write_byte(cmd, reg, true);
    i2c_master_start(cmd);
    i2c_master_write_byte(cmd, (address << 1) | I2C_MASTER_READ, true);
    if (size > 1) {
        i2c_master_read(cmd, data, size - 1, I2C_MASTER_ACK);
    }
    i2c_master_read_byte(cmd, data + size - 1, I2C_MASTER_NACK);
    i2c_master_stop(cmd);
    i2c_master_cmd_begin(I2C_MASTER_NUM, cmd, 1000 / portTICK_RATE_MS);
    i2c_cmd_link_delete(cmd);
}

void i2c_test_task(void *arg)
{
    uint8_t data = 0;
    while (1) {
        // 向从设备写入数据
        i2c_master_write_slave(0x3C, 0x00, 0x01);
        // 从从设备读取数据
        i2c_master_read_slave(0x3C, 0x00, &data, 1);
        printf("Read data from slave: 0x%02X\n", data);
        vTaskDelay(1000 / portTICK_PERIOD_MS);
    }
}

void app_main()
{
    i2c_master_init();
    xTaskCreate(i2c_test_task, "i2c_test_task", 1024 * 2, NULL, 10, NULL);
}

该代码通过 `i2c_master_init()` 初始化 I2C 主机，并提供了两个函数：`i2c_master_write_slave()` 和 `i2c_master_read_slave()`，用于向从设备写入数据和从从设备读取数据。

在 `i2c_test_task()` 中，我们首先向从设备写入数据（0x01），然后从从设备读取一个字节的数据，并将其打印到控制台上。这个任务会每秒钟重复执行一次。

注意：在使用此代码之前，请确保您已正确连接 I2C 总线和从设备，并将它们的地址设置为 0x3C。