RT-thread系统ADC无法正确读取内部温度,基准和VBAT通道数据的问题原因

原因是通道号对应到实际hal库中的通道名不正确

STM32L431芯片中内部VREFIN通道是0,如果直接使用0号通道去读取将获取错误的adc值,需要修改drv_adc.c中的stm32_adc_get_channel函数,将返回的通道号改为ADC_CHANNEL_VREFINT

17通道对应ADC_CHANNEL_TEMPSENSOR

18通道对应ADC_CHANNEL_VBAT

static rt_uint32_t stm32_adc_get_channel(rt_uint32_t channel)
{
    rt_uint32_t stm32_channel = 0;

    switch (channel)
    {
    case  0:
        stm32_channel = ADC_CHANNEL_VREFINT;
        break;
    case  1:
        stm32_channel = ADC_CHANNEL_1;
        break;
    case  2:
        stm32_channel = ADC_CHANNEL_2;
        break;
    case  3:
        stm32_channel = ADC_CHANNEL_3;
        break;
    case  4:
        stm32_channel = ADC_CHANNEL_4;
        break;
    case  5:
        stm32_channel = ADC_CHANNEL_5;
        break;
    case  6:
        stm32_channel = ADC_CHANNEL_6;
        break;
    case  7:
        stm32_channel = ADC_CHANNEL_7;
        break;
    case  8:
        stm32_channel = ADC_CHANNEL_8;
        break;
    case  9:
        stm32_channel = ADC_CHANNEL_9;
        break;
    case 10:
        stm32_channel = ADC_CHANNEL_10;
        break;
    case 11:
        stm32_channel = ADC_CHANNEL_11;
        break;
    case 12:
        stm32_channel = ADC_CHANNEL_12;
        break;
    case 13:
        stm32_channel = ADC_CHANNEL_13;
        break;
    case 14:
        stm32_channel = ADC_CHANNEL_14;
        break;
    case 15:
        stm32_channel = ADC_CHANNEL_15;
        break;
#ifdef ADC_CHANNEL_16
    case 16:
        stm32_channel = ADC_CHANNEL_16;
        break;
#endif
    case 17:
        stm32_channel = ADC_CHANNEL_TEMPSENSOR;
        break;
#ifdef ADC_CHANNEL_18
    case 18:
        stm32_channel = ADC_CHANNEL_VBAT;
        break;
#endif
#ifdef ADC_CHANNEL_19
    case 19:
        stm32_channel = ADC_CHANNEL_19;
        break;
#endif
    }

    return stm32_channel;
}