iic 多字节读出现问题，还请指导，谢谢

发布于 2019-01-21 11:42:13 浏览：3741 订阅该版

9 个回答

flyboy 2019-01-21

Do my self();

```
static struct rt_i2c_bus_device *i2c_bus_dev;

static int rt_i2c_write_reg(uint16_t addr, uint16_t reg, uint8_t *data, uint16_t len)
{
    rt_int8_t res = 0;
    rt_uint8_t tmp = reg;
    struct rt_i2c_msg msgs[2];

msgs[0].addr  = addr;  /* Slave address */
    msgs[0].flags = RT_I2C_WR;        /* Write flag */
    msgs[0].buf   = &tmp;             /* Slave register address */
    msgs[0].len   = 1;                /* Number of bytes sent */

msgs[1].addr  = addr;  /* Slave address */
    msgs[1].flags = RT_I2C_WR | RT_I2C_NO_START;        /* Read flag */
    msgs[1].buf   = data;              /* Read data pointer */
    msgs[1].len   = len;              /* Number of bytes read */

if (rt_i2c_transfer(i2c_bus_dev, msgs, 2) == 2)
    {
        res = RT_EOK;
    }
    else
    {
        res = -RT_ERROR;
    }

return res;
}

static int rt_i2c_read_reg(uint16_t addr, uint16_t reg, uint8_t *data, uint16_t len)
{
    rt_int8_t res = 0;
    rt_uint8_t tmp = reg;
    struct rt_i2c_msg msgs[2];

msgs[1].addr  = addr;  /* Slave address */
    msgs[1].flags = RT_I2C_RD;        /* Read flag */
    msgs[1].buf   = data;              /* Read data pointer */
    msgs[1].len   = len;              /* Number of bytes read */

if (rt_i2c_transfer(i2c_bus_dev, msgs, 2) == 2)
    {
        res = RT_EOK;
    }
    else
    {
        res = -RT_ERROR;
    }

return res;
}
```

你用这两个函数试试？