Stm32subeide (10) -- ADC scans multiple channels in DMA mode

summary

This chapter STM32CUBEMX To configure STM32F103 Of ADC stay DMA Mode scan multiple channels , Print through serial port .
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Generate routine

Use STM32CUBEMX Generate routine , Use here NUCLEO-F103RB Development board

Look at the schematic ,PA2 and PA3 Set as the serial port of the development board .

Configure serial port .

Open interrupt .

Look at the schematic ,Arduino The interface of A0-A5 All are AD mouth .

ADC Channel configuration

ADC1	IN0(PA0)	IN1(PA1)	IN4(PA4)

ADC1 To configure .

• ADCs_Common_Settings：
  • Mode：Independent mod Independent ADC Pattern , When using a ADC It's an independent mode , Use two ADC It's dual mode , In dual mode, there are many subdivision modes available , Specific configuration ADC_CR1:DUALMOD position .
• ADC_Settings：
  • Data Alignment：
    • Right alignment Right align the conversion result data , Generally, we choose right alignment mode .
    • Left alignment The conversion result data is left aligned .
  • Scan Conversion Mode：
    • Disabled Disable scan mode . If it's a single channel AD Conversion uses DISABLE.
    • Enabled Turn on scan mode . If it's multichannel AD Conversion uses ENABLE.
  • Continuous Conversion Mode：
    • Disabled Single conversion . To stop the conversion after one time, manual control is needed to restart the conversion .
    • Enabled Automatic continuous conversion .
  • DiscontinuousConvMode：
    • Disabled Disable interrupt mode . This is necessary in products that need to consider power consumption , That is, when an event triggers , Turn on the switch .
    • Enabled Turn on break mode .
• ADC_Regular_ConversionMode：
  • Enable Regular Conversions Whether to enable rule conversion .
  • Number Of Conversion ADC Number of conversion channels , Just write a few of them .
  • External Trigger Conversion Source External trigger selection . There are many options for this , Generally, software trigger mode is adopted .
• Rank：
  • Channel ADC Switching channels
  • Sampling Time Sampling period selection , The shorter the sampling period ,ADC The shorter the output period of the converted data, the lower the accuracy of the data , The longer the sampling period ,ADC The longer the output period of the converted data, the higher the accuracy of the data .
• ADC_Injected_ConversionMode：
  • Enable Injected Conversions Whether to enable injection conversion . Injection channels only appear when regular channels exist .
• WatchDog：
  • Enable Analog WatchDog Mode Whether the watchdog interrupt can be simulated . When ADC When the converted analog voltage is below the low threshold or above the high threshold , There will be interruptions .

DMA Turn on .

Generate a separate file .

STM32CUBEIDE To configure

If you need to print floating point type , You need to check the following options .

Serial port redirection

stay main.c in , Add header file , If you don't add it, it will appear identifier “FILE” is undefined Report errors .

/* USER CODE BEGIN Includes */
#include "stdio.h"
/* USER CODE END Includes */

Function declaration and serial port redirection ：

/* USER CODE BEGIN PFP */
#ifdef __GNUC__ // Serial port redirection 
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif 
PUTCHAR_PROTOTYPE
{
    
    HAL_UART_Transmit(&huart2 , (uint8_t *)&ch, 1, 0xFFFF);
    return ch;
}
/* USER CODE END PFP */

Code

Defining variables , Store the collected data .

/* USER CODE BEGIN 0 */
uint32_t ADC1_1, ADC1_2,ADC1_3;// Three channels of acquisition ADC
uint32_t ADC1_Value[30];//DMA Store array 
uint8_t i;
uint8_t ADC1_Flag;//dma Interruption after collection 
/* USER CODE END 0 */

Can make ADC transmission .

  /* USER CODE BEGIN 2 */
  HAL_ADC_Start_DMA(&hadc1,(uint32_t*)&ADC1_Value,30);    // Use DMA transmission 
  /* USER CODE END 2 */

Main circulation .

  /* USER CODE BEGIN WHILE */
  while (1)
  {
    
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
	  if(ADC1_Flag==1)
	  {
    
		  ADC1_Flag=0;
		  ADC1_1=0;
		  ADC1_2=0;
		  ADC1_3=0;
		  for(i=0;i<30;)
		  {
    
			  ADC1_1+=ADC1_Value[i++];
			  ADC1_2+=ADC1_Value[i++];
			  ADC1_3+=ADC1_Value[i++];
		  }
		  printf("\n");
		  printf("adc1_IN0(PA0)=%4.0d,ADC_IN0=%1.4f\r\n",ADC1_1/10,ADC1_1/10*3.3f/4096);
		  printf("adc1_IN1(PA1)=%4.0d,ADC_IN1=%1.4f\r\n",ADC1_2/10,ADC1_2/10*3.3f/4096);
		  printf("adc1_IN4(PA4)=%4.0d,ADC_IN2=%1.4f\r\n",ADC1_3/10,ADC1_3/10*3.3f/4096);
		  HAL_ADC_Start_DMA(&hadc1,(uint32_t*)&ADC1_Value,30);    // Use DMA transmission 
	  }
		HAL_Delay(1000);
  }
  /* USER CODE END 3 */

ADC Callback function .
DMA If you read memory segments during transmission , There will be problems with the arbiter , Added a sentence close DMA The sentence of HAL_ADC_Stop_DMA(&hadc1);

/* USER CODE BEGIN 4 */
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc)
{
    
	if(hadc->Instance == ADC1){
    
		ADC1_Flag=1;
		/* * DMA If you read memory segments during transmission , There will be problems with the arbiter , Added a sentence close DMA The language of  */
		HAL_ADC_Stop_DMA(&hadc1);
	}
}
/* USER CODE END 4 */

test result

Input a fixed voltage for testing .

ADC1	IN0(PA0)	IN1(PA1)	IN4(PA4)
Input voltage	VCC	2.0V	GND

Normal The test results are as follows .

If you don't try, close DMA The sentence of HAL_ADC_Stop_DMA(&hadc1);
Will cause data confusion .

Circular It can be collected all the time , Unwanted HAL_ADC_Stop_DMA(&hadc1) All right .

Last

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