STM32_ADC_HAL - GitMasterNikanjam/ARM_WiKi GitHub Wiki
There are three method to get the ADC data from sensor.
1- POLLFORCONVERSION
2- INTERRUPT
3- DMA
Also, it can be used in Single Mode or Multiple Channel Mode to acquire data.
In Single Mode, only one channel of the ADC is used.
In Multiple Mode, a multi-channel ADC is used.
Important Functions and Variable
ADC_HandleTypeDef hadc1;
typedef struct
{
uint32_t Channel; /*!< Specifies the channel to configure into ADC regular group.
This parameter can be a value of @ref ADC_channels */
uint32_t Rank; /*!< Specifies the rank in the regular group sequencer.
This parameter must be a number between Min_Data = 1 and Max_Data = 16 */
uint32_t SamplingTime; /*!< Sampling time value to be set for the selected channel.
Unit: ADC clock cycles
Conversion time is the addition of sampling time and processing time (12 ADC clock cycles at ADC resolution 12 bits, 11 cycles at 10 bits, 9 cycles at
8 bits, 7 cycles at 6 bits).
This parameter can be a value of @ref ADC_sampling_times
Caution: This parameter updates the parameter property of the channel, that can be used into regular and/or injected groups.
If this same channel has been previously configured in the other group (regular/injected), it will be updated to last setting.
Note: In case of usage of internal measurement channels (VrefInt/Vbat/TempSensor),
sampling time constraints must be respected (sampling time can be adjusted in function of ADC clock frequency and sampling time setting)
Refer to device datasheet for timings values, parameters TS_vrefint, TS_temp (values rough order: 4us min). */
uint32_t Offset; /*!< Reserved for future use, can be set to 0 */
}ADC_ChannelConfTypeDef;
HAL_StatusTypeDef HAL_ADC_Init(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_Start(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_Stop(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_PollForConversion(ADC_HandleTypeDef* hadc, uint32_t Timeout);
HAL_StatusTypeDef HAL_ADC_Start_IT(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_Stop_IT(ADC_HandleTypeDef* hadc);
void HAL_ADC_IRQHandler(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_Start_DMA(ADC_HandleTypeDef* hadc, uint32_t* pData, uint32_t Length);
HAL_StatusTypeDef HAL_ADC_Stop_DMA(ADC_HandleTypeDef* hadc);
uint32_t HAL_ADC_GetValue(ADC_HandleTypeDef* hadc);
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc);
HAL_StatusTypeDef HAL_ADC_ConfigChannel(ADC_HandleTypeDef* hadc, ADC_ChannelConfTypeDef* sConfig);
POLLFORCONVERSION Method for Multiple channels
1- Select and enable channels of adc in STM32CUBEMX software. for example select IN0 and IN1 for ADC1.
2- Config The ADC Configuration tab as below as:
Select Number of conversion: 2
For each channel, parameters such as sampling time and rank can be chosen.
Generate the code.
3- In the code, there are some functions that initialize the ADC and define the HAL ADC structure for ADC1.
ADC_HandleTypeDef hadc1;
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_DIV4;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.ScanConvMode = ENABLE;
hadc1.Init.ContinuousConvMode = DISABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.NbrOfConversion = 2;
hadc1.Init.DMAContinuousRequests = DISABLE;
hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_1;
sConfig.Rank = 2;
sConfig.SamplingTime = ADC_SAMPLETIME_28CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
4- There are some changes that needed to do.
In the MX_ADC1_Init() function, you must change hadc1.Init.NbrOfConversion to 1.
and comment all setting for Channels and ranks.
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_DIV4;
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.ScanConvMode = ENABLE;
hadc1.Init.ContinuousConvMode = DISABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.NbrOfConversion = 1;
hadc1.Init.DMAContinuousRequests = DISABLE;
hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
if (HAL_ADC_Init(&hadc1) != HAL_OK)
{
Error_Handler();
}
/** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
/*
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
*/
/** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
/*
sConfig.Channel = ADC_CHANNEL_1;
sConfig.Rank = 2;
sConfig.SamplingTime = ADC_SAMPLETIME_28CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
*/
/* USER CODE BEGIN ADC1_Init 2 */
/* USER CODE END ADC1_Init 2 */
}
5- Define functions in global space in main.c file for selection of channel and relative settings.
Notic that in all these functions the sConfig.Rank is 1.
void adc_select_0(void)
{
ADC_ChannelConfTypeDef sConfig = {0};
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
}
void adc_select_1(void)
{
ADC_ChannelConfTypeDef sConfig = {0};
sConfig.Channel = ADC_CHANNEL_1;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_28CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
}
6- now you can use these below code in while/loop for reading adc channel 0 and 1.
while (1)
{
adc_select_0();
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1, 100);
val[0] = HAL_ADC_GetValue(&hadc1);
HAL_ADC_Stop(&hadc1);
adc_select_1();
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1, 100);
val[1] = HAL_ADC_GetValue(&hadc1);
HAL_ADC_Stop(&hadc1);
HAL_Delay(100);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
INTERRUPT Method for Multiple channels
1- Select and enable multiple ADC channel. eg IN0 and IN1.
2- Enable Scan conversion mode and disable Continuous conversion.
Select EOC flag at the end of single channel conversion.
select number of conversion for regular conversion mode to 1.
3- Enable NVIC for ADC interrupts.
4- Generate the code and go to code and main.c file
in main.c file above of main function write this below code:
volatile uint32_t val1,val2;
ADC_ChannelConfTypeDef sConfig = {0};
volatile uint8_t adc_flag = 0; // flag for adc interrupt is busy
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc)
{
if(sConfig.Channel == ADC_CHANNEL_0)
val1 = HAL_ADC_GetValue(&hadc1);
else if(sConfig.Channel == ADC_CHANNEL_1)
val2 = HAL_ADC_GetValue(&hadc1);
adc_flag = 0;
}
void ADC_Read_IT(uint8_t channel_number) // function for select adc channel and request interrupt for that
{
while(adc_flag == 1){}
adc_flag = 1;
sConfig.Rank = 1;
switch(channel_number)
{
case 0:
sConfig.Channel = ADC_CHANNEL_0;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
break;
case 1:
sConfig.Channel = ADC_CHANNEL_1;
sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
break;
}
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
{
Error_Handler();
}
HAL_ADC_Start_IT(&hadc1);
}
and in while loop you can write for read adc of each channels that you need.
while (1)
{
ADC_Read_IT(0); // read adc channel 0 by interrupt
ADC_Read_IT(1); // read adc channel 1 by interrupt
HAL_Delay(5);
}
DMA Method for Multiple channels
1- Select and enable multiple ADC channel eg IN0 and IN1.
2- Set ADC configuration as below as:
Dont Forget to enable DMA continuous Requests.
3- Set DMA for ADC as below as:
Choose Word width for DMA because of 12bit of ADC resolution.
4- Generate the code and go to main.c file.
define a uint32_t val[2] variable in global space.
write HAL_ADC_Start_DMA(&hadc1, val, 2); before while loop.
now the adc values store in val variable.