DAC通道1可以开启，通道2开不起来

发布于 2022-05-17 15:12:36 浏览：639 订阅该版

```c
#define DAC_DEV_NAME        "dac1"  /* DAC 设备名称 */
#define DAC_DEV_CHANNEL1     1       /* DAC 通道 */
#define DAC_DEV_CHANNEL2     2       /* DAC 通道 */
rt_dac_device_t dac_dev;            /* DAC 设备句柄 */
rt_uint32_t value = 1350;          /* DAC 数据保持寄存器值 */

//--------------------DAC初始化--------------------------
    /* 查找设备 */
    dac_dev = (rt_dac_device_t)rt_device_find(DAC_DEV_NAME);
    if (dac_dev == RT_NULL)
    {
        rt_kprintf("dac sample run failed! can't find %s device!\n", DAC_DEV_NAME);
        return RT_ERROR;
    }
    /* 使能设备 */
    rt_dac_enable(dac_dev, DAC_DEV_CHANNEL1);
    /* 设置输出值 */
    rt_dac_write(dac_dev, DAC_DEV_CHANNEL1, value);

/* 使能设备 */
      rt_dac_enable(dac_dev, DAC_DEV_CHANNEL2);
      /* 设置输出值 */
      rt_dac_write(dac_dev, DAC_DEV_CHANNEL2, value);
```
     
通道1可以正常输出，通道2就不行，EN1位是1，有输出，EN2位还是0，无输出。通道2，定义为2。采用STM32F103RC。

![image.png](https://oss-club.rt-thread.org/uploads/20220517/a6892b8c9ed9cd953e7e24cc6356182f.png)
![image.png](https://oss-club.rt-thread.org/uploads/20220517/2ddda99e55f8abacfe5655b967bca314.png)

用命令显示可以成功，但是寄存器内容一点没有变，也没有输出。