I2C

Artpi尝试移植硬件I2C踩坑

发布于 2022-11-04 01:30:23 浏览：242 订阅该版

手头在做毕业设计，使用的主控是Artpi，传感器是LSM6DSL。但是由于需要采集高频振动信号，超过了软件IIC的采样速率，于是在各路大佬的帮助下开始了对硬件IIC的移植之路：
首先使用cubemx配制`I2C3（SCL->PA8,SDA->PH8）`

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20221104/e86f30bf532c25a3140074ca3e1536d2.png)
之后，将生成的main.c和msp.c里的I2C3代码分别移植到新建的HWI2C中：

```c
static void MX_GPIO_Init(void);
static void MX_I2C3_Init(void);

static struct rt_i2c_bus_device i2c3_bus;
I2C_HandleTypeDef hi2c3;
static void MX_GPIO_Init(void)
{

/* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();

}

static void MX_I2C3_Init(void)
{

/* USER CODE BEGIN I2C3_Init 0 */

/* USER CODE END I2C3_Init 0 */

/* USER CODE BEGIN I2C3_Init 1 */

/* USER CODE END I2C3_Init 1 */
  hi2c3.Instance = I2C3;
  hi2c3.Init.Timing = 0x00B03FDB;
  hi2c3.Init.OwnAddress1 = 0;
  hi2c3.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c3.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c3.Init.OwnAddress2 = 0;
  hi2c3.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c3.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c3.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c3) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Analogue filter
  */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c3, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Digital filter
  */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c3, 0) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C3_Init 2 */

/* USER CODE END I2C3_Init 2 */

}
```

```c
void HAL_I2C_MspInit(I2C_HandleTypeDef* hi2c)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(hi2c->Instance==I2C3)
  {
  /* USER CODE BEGIN I2C3_MspInit 0 */

/* USER CODE END I2C3_MspInit 0 */

__HAL_RCC_GPIOA_CLK_ENABLE();
    __HAL_RCC_GPIOH_CLK_ENABLE();
    /**I2C3 GPIO Configuration
    PA8     ------> I2C3_SCL
    PH8     ------> I2C3_SDA
    */
    GPIO_InitStruct.Pin = GPIO_PIN_8;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF4_I2C3;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

GPIO_InitStruct.Pin = GPIO_PIN_8;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF4_I2C3;
    HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

/* Peripheral clock enable */
    __HAL_RCC_I2C3_CLK_ENABLE();

/* USER CODE BEGIN I2C3_MspInit 1 */

/* USER CODE END I2C3_MspInit 1 */
  }

}
```

之后，请教了大佬，编辑了一段硬件IIC的代码，并添加了LSM6DSL的包，并根据readme进行了传感器的注册：

```c
static rt_size_t i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
{
    struct rt_i2c_msg *msg;
    rt_int32_t i, ret;

for(i = 0; i< num; i++)
    {
        msg = &msgs[i];
        if(msg->flags & RT_I2C_RD)
        {
            //HAL_I2C_Master_Receive(&hi2c3, msg->addr, msg->buf, msg->len, 100);
            HAL_I2C_Master_Receive(&hi2c3, msg->addr, msg->buf, msg->len, 100);
        }
        else
        {
            HAL_I2C_Master_Transmit(&hi2c3, msg->addr, msg->buf, msg->len, 100);
        }
    }
    ret = i;
    return ret;
}

static const struct rt_i2c_bus_device_ops i2c_bus_ops =
{
    i2c_xfer,
    RT_NULL,
    RT_NULL
};

int rt_i2c_hw_init(void)
{
    MX_GPIO_Init();
    MX_I2C3_Init();
    i2c3_bus.ops = &i2c_bus_ops;
    rt_i2c_bus_device_register(&i2c3_bus, "hw_i2c");
    return RT_EOK;
}
INIT_DEVICE_EXPORT(rt_i2c_hw_init);

#include "sensor_st_lsm6dsl.h"
int lsm6dsl_port(void)
{
    struct rt_sensor_config cfg;
    cfg.intf.dev_name = "hw_i2c";
    cfg.intf.user_data = (void *)LSM6DSL_ADDR_DEFAULT;
    cfg.irq_pin.pin = RT_PIN_NONE;
    rt_hw_lsm6dsl_init("lsm6dsl", &cfg);
    return 0;
}
INIT_APP_EXPORT(lsm6dsl_port);
```

但是现在遇到的问题有两个：
1、没有接上传感器时，仍显示注册成功

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20221104/ca7bc58788b165c2f468b4fb511b9b62.png)

2、接上传感器时，使用sensor_polling acce_lsm ,读出数值全为0

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20221104/cf459625d3aad074ec333417c54570dd.png)

请问是否有大佬做过相关的工作，能否提供一些帮助，可以有偿，感激不尽