STM32H723 ADC+DMA 误差解决

很多论坛提到STM32H723 ADC不准的问题，在安富莱的论坛上很多。实测STM32Cube FW_H7 V1.9.1这个库生成的ADC的驱动代码可以实现ADC的精确测量。
需要注意的是在ADC的初始化后，要对ADC进行校准，如果不进行校准ADC1 ADC2会有50个ADC左右的误差，ADC3 有接近130个ADC值得误差。

`void MX_ADC3_Init(void)
{

/* USER CODE BEGIN ADC3_Init 0 */

/* USER CODE END ADC3_Init 0 */

ADC_ChannelConfTypeDef sConfig = {0};

/* USER CODE BEGIN ADC3_Init 1 */

/* USER CODE END ADC3_Init 1 /
/* Common config
/
hadc3.Instance = ADC3;
hadc3.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
hadc3.Init.DataAlign = ADC3_DATAALIGN_RIGHT;
hadc3.Init.ScanConvMode = ADC_SCAN_ENABLE;
hadc3.Init.EOCSelection = ADC_EOC_SEQ_CONV;
hadc3.Init.LowPowerAutoWait = DISABLE;
hadc3.Init.ContinuousConvMode = ENABLE;
hadc3.Init.NbrOfConversion = 5;
hadc3.Init.DiscontinuousConvMode = DISABLE;
hadc3.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc3.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc3.Init.DMAContinuousRequests = ENABLE;
hadc3.Init.SamplingMode = ADC_SAMPLING_MODE_NORMAL;
hadc3.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DMA_CIRCULAR;
hadc3.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN;
hadc3.Init.LeftBitShift = ADC_LEFTBITSHIFT_NONE;
hadc3.Init.OversamplingMode = DISABLE;
if (HAL_ADC_Init(&hadc3) != HAL_OK)
{
Error_Handler();
}
/* Configure Regular Channel
/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = ADC_REGULAR_RANK_1;
sConfig.SamplingTime = ADC3_SAMPLETIME_640CYCLES_5;
sConfig.SingleDiff = ADC_SINGLE_ENDED;
sConfig.OffsetNumber = ADC_OFFSET_NONE;
sConfig.Offset = 0;
sConfig.OffsetSign = ADC3_OFFSET_SIGN_NEGATIVE;
sConfig.OffsetSaturation = DISABLE;
if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* Configure Regular Channel
/
sConfig.Channel = ADC_CHANNEL_6;
sConfig.Rank = ADC_REGULAR_RANK_2;
if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* Configure Regular Channel
/
sConfig.Channel = ADC_CHANNEL_7;
sConfig.Rank = ADC_REGULAR_RANK_3;
if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* Configure Regular Channel
/
sConfig.Channel = ADC_CHANNEL_9;
sConfig.Rank = ADC_REGULAR_RANK_4;
if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* Configure Regular Channel
/
sConfig.Channel = ADC_CHANNEL_10;
sConfig.Rank = ADC_REGULAR_RANK_5;
if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
{
Error_Handler();
}
/ USER CODE BEGIN ADC3_Init 2 /
HAL_ADCEx_Calibration_Start(&hadc3,ADC_CALIB_OFFSET,ADC_SINGLE_ENDED);
/ USER CODE END ADC3_Init 2 */