【STM32CubeMX】5，STM32之ADC

程序员文章站 2024-02-25 14:38:15

...

1，初步配置。对于滑动变阻器的电压输出

还有就是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，以轮寻模式来运行

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 */

使用下面函数中的一个**ADC外设:

HAL_ADC_Start() -- 轮询模式

HAL_ADC_Start_IT(), -- 中断模式

HAL_ADC_Start_DMA(). -- DMA模式

ADC_ConvertedValueLocal =(float) ADC_ConvertedValue/4096*3.3; //不同的类型有不同的转换公式，但一般都要除以4096

3，不同的模式进入赋值的判断语句不同

例子，ADC工作状态均为非阻塞

1 轮询模式 -- 非阻塞

1
2
3
4
5
6
7
8
9
10

/*##-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 中断模式

1
2
3
4
5
6
7

/*##-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

1
2
3
4
5
6
7

/*##-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);
}

3、几个函数

callback函数

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中断、DMA传输、看门狗超过阀值、发生Adc错误，这些函数返回前都调用了Callback函数，用来在非中断模式下处理Adc数据，如果想进行一些操作可以直接修改Callback函数。

/**HAL_ADC_GetValue(ADC_HandleTypeDef* hadc)

官方给的解释说明很好用

* @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(), 在中断模式下，参考HAL_ADC_IRQHandler()

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

在轮询模式下，参考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),用来做轮询或中断标记；每个rank转换结束，或序列转换结束；

MSP:MCU Specific Package

4，DMA多通道的ADC