刚开始用RTT，请教I2C驱动的用法

发布于 2013-07-16 22:45:17 浏览：2569 订阅该版

3 个回答

nongxiaoming 2013-07-17

rt-thread大师兄

I2C发送N个字节不接收：

```
struct rt_i2c_bus_device * i2c_bus;
    struct rt_i2c_msg msg;
	 uint8_t send_buf[n];
	 i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(i2c_bus_name);//这里写你的I2C设备名称
	 RT_ASSERT(i2c_bus != RT_NULL);
   
   //这里填充你要发送的数据到buf
     send_buf[0] =....;
    .........
	 
    msg.addr  = I2C_ADDR;           //这里写你的器件的I2C地址
    msg.flags = RT_I2C_WR;         //标志为写数据
    msg.len   = n;                         //这里写你发送是数据长度
    msg.buf   = send_buf;             //发送的数据指针
    rt_i2c_transfer(i2c_bus, &msg, 1);   //发送数据，后面的1表示你的rt_i2c_msg为一个，可为多个

```

I2C发送N个数据同时接收N+1个数据：

```
struct rt_i2c_bus_device * i2c_bus;
    struct rt_i2c_msg msg[2];
	    uint8_t send_buf[n];
    uint8_t recv_buf[n+1];
	 i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(i2c_bus_name);
	 RT_ASSERT(i2c_bus != RT_NULL);

//填充你要发送的数据到buf
    send_buf[0] = ...;
    ........
    msg[0].addr  = I2C_ADDR;
    msg[0].flags = RT_I2C_WR;
    msg[0].len   = n;
    msg[0].buf   = send_buf;
	
   msg[1].addr  = I2C_ADDR;
    msg[1].flags = RT_I2C_RD;
    msg[1].len   = n+1;
    msg[1].buf   = recv_buf;
rt_i2c_transfer(i2c_bus, msg, 2);
```

qq_逸 2013-11-01

这家伙很懒，什么也没写！

>I2C发送N个字节不接收：
>
>
>```
>struct rt_i2c_bus_device * i2c_bus;
>    struct rt_i2c_msg msg;
>	 uint8_t send_buf[n];
>	 i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(i2c_bus_name);//这里写你的I2C设备名称
>	 RT_ASSERT(i2c_bus != RT_NULL);
>   
>   //这里填充你要发送的数据到buf
>     send_buf[0] =....;
>    .........
>	 
>    msg.addr  = I2C_ADDR;           //这里写你的器件的I2C地址
>    msg.flags = RT_I2C_WR;         //标志为写数据
>    msg.len   = n;                         //这里写你发送是数据长度
>    msg.buf   = send_buf;             //发送的数据指针
>    rt_i2c_transfer(i2c_bus, &msg, 1);   //发送数据，后面的1表示你的rt_i2c_msg为一个，可为多个
>
>```
>
>
>I2C发送N个数据同时接收N+1个数据：
>
>
>```
>struct rt_i2c_bus_device * i2c_bus;
>    struct rt_i2c_msg msg[2];
>	    uint8_t send_buf[n];
>    uint8_t recv_buf[n+1];
>	 i2c_bus = (struct rt_i2c_bus_device *)rt_device_find(i2c_bus_name);
>	 RT_ASSERT(i2c_bus != RT_NULL);
>
>   //填充你要发送的数据到buf
>    send_buf[0] = ...;
>    ........
>    msg[0].addr  = I2C_ADDR;
>    msg[0].flags = RT_I2C_WR;
>    msg[0].len   = n;
>    msg[0].buf   = send_buf;
>	
>   msg[1].addr  = I2C_ADDR;
>    msg[1].flags = RT_I2C_RD;
>    msg[1].len   = n+1;
>    msg[1].buf   = recv_buf;
>rt_i2c_transfer(i2c_bus, msg, 2);
>```

---

请教一下，如果在应用程序中这么用的话，device.c中提供的read,write等那些函数岂不是没用了吗？