STM32G070填坑(2)--ADC多通道数据采集
STM32G070的ADC多通道采集
- 1. 非DMA方式采集
- 1.1 关于ADC扫描定序（scan sequencer）
- 2. DMA方式采集
本文讲述基于STM32G070进行ADC多通道采集，并分别介绍非DMA方式和DMA方式。
1. 非DMA方式采集
ADC初始化代码如下（使用STM32CubeMx自动生成），配置了3个通道：
static void MX_ADC1_Init(void)
{
/* USER CODE BEGIN ADC1_Init 0 */
/* USER CODE END ADC1_Init 0 */
ADC_ChannelConfTypeDef sConfig = {0};
/* USER CODE BEGIN ADC1_Init 1 */
/* USER CODE END ADC1_Init 1 */
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc1.Instance = ADC1;
hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
hadc1.Init.LowPowerAutoWait = DISABLE;
hadc1.Init.LowPowerAutoPowerOff = DISABLE;
hadc1.Init.ContinuousConvMode = DISABLE;
hadc1.Init.NbrOfConversion = 3;
hadc1.Init.DiscontinuousConvMode = ENABLE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.DMAContinuousRequests = DISABLE;
hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
hadc1.Init.SamplingTimeCommon1 = ADC_SAMPLETIME_1CYCLE_5;
hadc1.Init.SamplingTimeCommon2 = ADC_SAMPLETIME_1CYCLE_5;
hadc1.Init.OversamplingMode = DISABLE;
hadc1.Init.TriggerFrequencyMode = ADC_TRIGGER_FREQ_HIGH;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_4;
sConfig.Rank = ADC_REGULAR_RANK_1;
sConfig.SamplingTime = ADC_SAMPLINGTIME_COMMON_1;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_5;
sConfig.Rank = ADC_REGULAR_RANK_2;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_9;
sConfig.Rank = ADC_REGULAR_RANK_3;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
获取ADC数据
// 校准
HAL_ADCEx_Calibration_Start(&hadc1);
for (idx = 0; idx < 3; idx++)
{
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1, 50);
/* Check if the continous conversion is finished */
if(HAL_IS_BIT_SET(HAL_ADC_GetState(&hadc1), HAL_ADC_STATE_REG_EOC))
{
/* Get the converted value */
AD_Value[idx] = HAL_ADC_GetValue(&hadc1);
}
}
HAL_ADC_Stop(&hadc1);
1.1 关于ADC扫描定序（scan sequencer）
ADC scan sequencer can be used in two different modes. 配置ADC多通道采集时，对于各个通道的采集顺序有两种方式：
- Sequencer fully configurable (The order in which the channels are scanned is independent from the channel number)
采用这种方式时，ADC的通道扫描顺序将和channel number不再相关，如1中代码，就采用了这种方式
//扫描方式：ADC_SCAN_ENABLE
hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
//...
sConfig.Channel = ADC_CHANNEL_5;
sConfig.Rank = ADC_REGULAR_RANK_2;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
sConfig.Channel = ADC_CHANNEL_6;
sConfig.Rank = ADC_REGULAR_RANK_1;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
如果按照如上代码配置，在采集时，将先采集channel 6，再采集channel 5。但是使用该方式时，需要注意Only channel 0 to channel 14 can be selected in this sequence。即channel 15/16/17/18无法使用该方式，如果需要使用channel 15-18，则可以使用下面第二种扫描方式。
- Sequencer not fully configurable (The order in which the channels are scanned is defined by the channel number)
这种方式比较好理解，就是按照channel number的大小，按顺序进行扫描，配置代码如下：
// 扫描方式：ADC_SCAN_SEQ_FIXED
hadc1.Init.ScanConvMode = ADC_SCAN_SEQ_FIXED;
sConfig.Channel = ADC_CHANNEL_16;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
2. DMA方式采集
直接上代码：
static void MX_ADC1_Init(void)
{
/* USER CODE BEGIN ADC1_Init 0 */
/* USER CODE END ADC1_Init 0 */
ADC_ChannelConfTypeDef sConfig = {0};
/* USER CODE BEGIN ADC1_Init 1 */
/* USER CODE END ADC1_Init 1 */
/** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc1.Instance = ADC1;
hadc1.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.ScanConvMode = ADC_SCAN_SEQ_FIXED;
hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
hadc1.Init.LowPowerAutoWait = DISABLE;
hadc1.Init.LowPowerAutoPowerOff = DISABLE;
hadc1.Init.ContinuousConvMode = ENABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.DMAContinuousRequests = ENABLE;
hadc1.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN;
hadc1.Init.SamplingTimeCommon1 = ADC_SAMPLETIME_12CYCLES_5;
hadc1.Init.OversamplingMode = DISABLE;
hadc1.Init.TriggerFrequencyMode = ADC_TRIGGER_FREQ_HIGH;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_4;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_5;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_9;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_10;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure Regular Channel
*/
sConfig.Channel = ADC_CHANNEL_16;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();
/* DMA interrupt init */
/* DMA1_Channel1_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);
}
void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(hadc->Instance==ADC1)
{
/* USER CODE BEGIN ADC1_MspInit 0 */
/* USER CODE END ADC1_MspInit 0 */
/* Peripheral clock enable */
__HAL_RCC_ADC_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/**ADC1 GPIO Configuration
PA4 ------> ADC1_IN4
PA5 ------> ADC1_IN5
PB1 ------> ADC1_IN9
PB2 ------> ADC1_IN10
PB12 ------> ADC1_IN16
*/
GPIO_InitStruct.Pin = GPIO_PIN_4|GPIO_PIN_5;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* ADC1 DMA Init */
/* ADC1 Init */
hdma_adc1.Instance = DMA1_Channel1;
hdma_adc1.Init.Request = DMA_REQUEST_ADC1;
hdma_adc1.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_adc1.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_adc1.Init.MemInc = DMA_MINC_ENABLE;
hdma_adc1.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
hdma_adc1.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
hdma_adc1.Init.Mode = DMA_CIRCULAR;
hdma_adc1.Init.Priority = DMA_PRIORITY_LOW;
if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(hadc,DMA_Handle,hdma_adc1);
/* USER CODE BEGIN ADC1_MspInit 1 */
/* USER CODE END ADC1_MspInit 1 */
}
}
初始化完成后，即可使用：
//开始ADC转换
HAL_ADCEx_Calibration_Start(&hadc1);
HAL_ADC_Start_DMA(&hadc1, (uint32_t *)&AD_Value_Buffer, AD_DMA_BUFF_LENGTH);
注：AD_Value_Buffer为事先定义好的数组，长度为AD_DMA_BUFF_LENGTH
接下来，无需CPU参与，DMA将会把ADC采集到数据搬运至AD_Value_Buffer的地址中，当长度达到AD_DMA_BUFF_LENGTH时，将从头开始，此时会覆盖数据。