【STM32CubeMX】5，STM32之ADC

阿新 • • 發佈：2019-02-19

1，初步配置。對於滑動變阻器的電壓輸出

還有就是printf、scanf的重定向，在uart.c中

int fputc (int ch ,FILE *f)
{
    HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,0xfff);
    return ch;
}

int fgetc(FILE *f)
{
    uint8_t ch;
    HAL_UART_Receive(&huart1,(uint8_t *)&ch,1,0xfff);
    return ch;
}

2，以輪尋模式來執行

while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
HAL_ADC_Start(&hadc2);
HAL_ADC_PollForConversion(&hadc2, 50);
if(HAL_ADC_STATE_REG_EOC)//²»»á×Ô¶¯¸´Î»
    {
    ADC_ConvertedValue=HAL_ADC_GetValue(&hadc2);
    ADC_ConvertedValueLocal =(float) ADC_ConvertedValue/4096*3.3; 
    printf("\r\n The current AD value = 0x%04X \r\n",  ADC_ConvertedValue); 
    printf("\r\n The current AD value = %f V \r\n",ADC_ConvertedValueLocal); 
    }
HAL_Delay(1000);
}
/* USER CODE END 3 */

 使用下面函式中的一個啟用ADC外設:
    HAL_ADC_Start() -- 輪詢模式
    HAL_ADC_Start_IT(), -- 中斷模式
    HAL_ADC_Start_DMA(). -- DMA模式
ADC_ConvertedValueLocal =(float) ADC_ConvertedValue/4096*3.3; //不同的型別有不同的轉換公式，但一般都要除以4096

3，不同的模式進入賦值的判斷語句不同

例子，ADC工作狀態均為非阻塞

1 輪詢模式 -- 非阻塞

/*##-3- Start the conversion process ######/

if(HAL_ADC_Start(&AdcHandle) != HAL_OK)

{ Error_Handler(); }

/*##-4- Wait for the end of conversion ######/

HAL_ADC_PollForConversion(&AdcHandle, 10);

if(HAL_ADC_GetState(&AdcHandle) == HAL_ADC_STATE_EOC_REG)

{

/*##-5- Get the converted value of channel ##*/

uhADCxConvertedValue = HAL_ADC_GetValue(&AdcHandle);

}

2 中斷模式

/*##-3- Start the conversion process ######/

if(HAL_ADC_StartIT(&AdcHandle) != HAL_OK)

{ Error_Handler(); }

void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* AdcHandle)

{ /* Get the converted value of regular channel */

uhADCxConvertedValue = HAL_ADC_GetValue(AdcHandle);

}

3 DMA模式

/*##-3- Start the conversion process ######/

if(HAL_ADC_StartDMA(&AdcHandle,&uhADCxConvertedValue,1) != HAL_OK)

{ Error_Handler(); }

void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* AdcHandle)

{ /* Turn LED1 on: Transfer process is correct */

BSP_LED_On(LED1);

}

4、幾個函式

callback函式

void                    HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc);
void                    HAL_ADC_ConvHalfCpltCallback(ADC_HandleTypeDef* hadc);
void                    HAL_ADC_LevelOutOfWindowCallback(ADC_HandleTypeDef* hadc);
void                    HAL_ADC_ErrorCallback(ADC_HandleTypeDef *hadc);
ADC中斷、DMA傳輸、看門狗超過閥值、發生Adc錯誤，這些函式返回前都呼叫了Callback函式，
用來在非中斷模式下處理Adc資料，如果想進行一些操作可以直接修改Callback函式。

/**HAL_ADC_GetValue(ADC_HandleTypeDef* hadc)

官方給的解釋說明很好用

* @brief Get ADC regular group conversion result.
* @note Reading register DR automatically clears ADC flag EOC
* (ADC group regular end of unitary conversion).
* @note This function does not clear ADC flag EOS
* (ADC group regular end of sequence conversion).
* Occurrence of flag EOS rising:
* - If sequencer is composed of 1 rank, flag EOS is equivalent
* to flag EOC.
* - If sequencer is composed of several ranks, during the scan
* sequence flag EOC only is raised, at the end of the scan sequence
* both flags EOC and EOS are raised.
* To clear this flag, either use function:

* in programming model IT: @ref HAL_ADC_IRQHandler(), 在中斷模式下，參考HAL_ADC_IRQHandler()

in programming model polling: @ref HAL_ADC_PollForConversion() or @ref __HAL_ADC_CLEAR_FLAG(&hadc, ADC_FLAG_EOS).

在輪詢模式下，參考HAL_ADC_PollForConversion()或者__HAL_ADC_CLEAR_FLAG(&hadc, ADC_FLAG_EOS)

* @param hadc: ADC handle
* @retval ADC group regular conversion data
*/
uint32_t HAL_ADC_GetValue(ADC_HandleTypeDef* hadc)
{
/* Check the parameters */
assert_param(IS_ADC_ALL_INSTANCE(hadc->Instance));

/* Note: EOC flag is not cleared here by software because automatically */
/* cleared by hardware when reading register DR. */

/* Return ADC converted value */
return hadc->Instance->DR;

}

uint32_tEOCSelection -- EOC(EndOfConversion),用來做輪詢或中斷標記；每個rank轉換結束，或序列轉換結束；

MSP:MCU Specific Package

5，DMA多通道的ADC