STM32F072CBU 微 Controller 。
我有多个 ADC 输入，并希望单独和单独读取它们。 STMcubeMX 生成样板代码，假设我希望按顺序读取所有输入，但我无法弄清楚如何更正此问题。
This blog post 表达了我遇到的同样问题，但给出的解决方案似乎不起作用。为每次转换打开和关闭 ADC 与返回值中的错误相关。只有当我在 STMcubeMX 中配置单个 ADC 输入，然后在不取消初始化 ADC 的情况下进行轮询时，才会返回准确的读数。
cubeMX 的 adc_init 函数:
/* ADC init function */
static void MX_ADC_Init(void)
{
ADC_ChannelConfTypeDef sConfig;
/**Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc.Instance = ADC1;
hadc.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
hadc.Init.Resolution = ADC_RESOLUTION_12B;
hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD;
hadc.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
hadc.Init.LowPowerAutoWait = DISABLE;
hadc.Init.LowPowerAutoPowerOff = DISABLE;
hadc.Init.ContinuousConvMode = DISABLE;
hadc.Init.DiscontinuousConvMode = DISABLE;
hadc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc.Init.DMAContinuousRequests = DISABLE;
hadc.Init.Overrun = ADC_OVR_DATA_PRESERVED;
if (HAL_ADC_Init(&hadc) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_0;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
sConfig.SamplingTime = ADC_SAMPLETIME_41CYCLES_5;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_1;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_2;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_3;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_4;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_VREFINT;
if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
}
主文件
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration----------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_ADC_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
//HAL_TIM_Base_Start_IT(&htim3);
init_printf(NULL, putc_wrangler);
HAL_ADCEx_Calibration_Start(&hadc);
HAL_ADC_DeInit(&hadc); // ADC is initialized for every channel change
schedule_initial_events();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
event_loop();
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
/* USER CODE END 3 */
}
我现在关闭 ADC 并重新初始化以更改 channel 的过程:
// Set up
ADC_ChannelConfTypeDef channelConfig;
channelConfig.SamplingTime = samplingT;
channelConfig.Channel = sensorChannel;
channelConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
if (HAL_ADC_Init(&hadc) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
if (HAL_ADC_ConfigChannel(&hadc, &channelConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
// Convert
uint16_t retval;
if (HAL_ADC_Start(&hadc) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
if (HAL_ADC_PollForConversion(&hadc, 1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
if (HAL_ADC_GetError(&hadc) != HAL_ADC_ERROR_NONE)
{
_Error_Handler(__FILE__, __LINE__);
}
retval = (uint16_t) HAL_ADC_GetValue(&hadc);
if (HAL_ADC_Stop(&hadc) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
// Close
HAL_ADC_DeInit(&hadc);
在这一点上，我不确定是否有办法完成我想要的，STM32 似乎在有源 ADC 线路上处于常规组并按顺序转换。
最佳答案
如果要在单次转换模式下读取多个 ADC channel ，则必须在每次读取之前更改 channel 设置，但不必重新初始化 ADC。简单的做如下，选择新的 channel (你也可以改变采样时间，如果 channel 必须不同，但一般可以相同)，选择 channel 等级，然后调用HAL_ADC_ConfigChannel函数。在此之后，您可以执行转换。
void config_ext_channel_ADC(uint32_t channel, boolean_t val)
{
ADC_ChannelConfTypeDef sConfig;
sConfig.Channel = channel;
sConfig.SamplingTime = ADC_SAMPLETIME_71CYCLES_5;
if(True == val)
{
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
}
else
{
sConfig.Rank = ADC_RANK_NONE;
}
HAL_ADC_ConfigChannel(&hadc, &sConfig);
}
uint32_t r_single_ext_channel_ADC(uint32_t channel)
{
uint32_t digital_result;
config_ext_channel_ADC(channel, True);
HAL_ADCEx_Calibration_Start(&hadc);
HAL_ADC_Start(&hadc);
HAL_ADC_PollForConversion(&hadc, 1000);
digital_result = HAL_ADC_GetValue(&hadc);
HAL_ADC_Stop(&hadc);
config_ext_channel_ADC(channel, False);
return digital_result;
}
使用示例:
#define SUPPLY_CURRENT ADC_CHANNEL_5
#define BATTERY_VOLTAGE ADC_CHANNEL_6
uint16_t r_battery_voltage(uint16_t mcu_vcc)
{
float vbat;
uint16_t digital_val;
digital_val = r_single_ext_channel_ADC(BATTERY_VOLTAGE);
vbat = (mcu_vcc/4095.0) * digital_val;
vbat = vbat * 2; // 1/2 voltage divider
return vbat;
}
uint16_t r_supply_current(uint16_t mcu_vcc)
{
float v_sense, current;
uint16_t digital_val;
digital_val = r_single_ext_channel_ADC(SUPPLY_CURRENT);
v_sense = (mcu_vcc/4095.0) * digital_val;
current = v_sense * I_SENSE_GAIN;
return current;
}
此代码用于 STM32F030。为了读取内部温度传感器和引用电压，需要设置与上述功能略有不同的版本，因为必须设置额外的启用位。
void config_int_channel_ADC(uint32_t channel, boolean_t val)
{
ADC_ChannelConfTypeDef sConfig;
sConfig.Channel = channel;
if(val == True)
{
if(channel == ADC_CHANNEL_VREFINT)
{
ADC->CCR |= ADC_CCR_VREFEN;
hadc.Instance->CHSELR = (uint32_t)(ADC_CHSELR_CHSEL17);
}
else if(channel == ADC_CHANNEL_TEMPSENSOR)
{
ADC->CCR |= ADC_CCR_TSEN;
hadc.Instance->CHSELR = (uint32_t)(ADC_CHSELR_CHSEL16);
}
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;
}
else if(val == False)
{
if(channel == ADC_CHANNEL_VREFINT)
{
ADC->CCR &= ~ADC_CCR_VREFEN;
hadc.Instance->CHSELR = 0;
}
else if(channel == ADC_CHANNEL_TEMPSENSOR)
{
ADC->CCR &= ~ADC_CCR_TSEN;
hadc.Instance->CHSELR = 0;
}
sConfig.Rank = ADC_RANK_NONE;
sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;
}
HAL_ADC_ConfigChannel(&hadc,&sConfig);
}
uint32_t r_single_int_channel_ADC(uint32_t channel)
{
uint32_t digital_result;
config_int_channel_ADC(channel, True);
HAL_ADCEx_Calibration_Start(&hadc);
HAL_ADC_Start(&hadc);
HAL_ADC_PollForConversion(&hadc, 1000);
digital_result = HAL_ADC_GetValue(&hadc);
HAL_ADC_Stop(&hadc);
config_int_channel_ADC(channel, False);
return digital_result;
}
用于 MCU VDD 计算的示例使用内部电压引用:
#define VREFINT_CAL_ADDR ((uint16_t*) ((uint32_t) 0x1FFFF7BA))
static float FACTORY_CALIB_VDD = 3.31;
uint16_t calculate_MCU_vcc()
{
float analog_Vdd;
uint16_t val_Vref_int = r_single_int_channel_ADC(ADC_CHANNEL_VREFINT);
analog_Vdd = (FACTORY_CALIB_VDD * (*VREFINT_CAL_ADDR))/val_Vref_int;
return analog_Vdd * 1000;
}
内部温度传感器读数:
#define TEMP30_CAL_ADDR ((uint16_t*) ((uint32_t) 0x1FFFF7B8))
#define TEMP110_CAL_ADDR ((uint16_t*) ((uint32_t) 0x1FFFF7C2))
static float FACTORY_CALIB_VDD = 3.31;
float r_MCU_temp(uint16_t mcu_vcc)
{
float temp;
float slope = ((110.0 - 30.0)/((*TEMP110_CAL_ADDR) - (*TEMP30_CAL_ADDR)));
uint16_t ts_data = r_single_int_channel_ADC(ADC_CHANNEL_TEMPSENSOR);
temp = ((mcu_vcc/FACTORY_CALIB_VDD) * ts_data)/1000;
temp = slope * (temp - (*TEMP30_CAL_ADDR)) + 30;
return round_to(temp, 0);
}
请注意，您的 MCU 的校准数据地址可能不同，请查看数据表了解更多信息。
关于c - 使用 STM32F0 ADC 单独读取不同的输入，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/45291690/