嗨,大家好,
我将 STM32F767 nucleo 与 STM32Cubeide 一起使用。我已将 ADC 配置为以 1.8Msps 的采样率与 DMA 一起运行。我通过以下方式计算了这个采样速度:
HCLK = 216MHz
PCLK2 = 108MHz
4 的预分频器:ADCCLK = 27MHz
分辨率(12 位 + 3)
因此采样率 = 27Mhz / 15 = 1.8Msps
ADC 由 tiM2 硬件触发,使用 DMA 对 50 个样本进行采样,当使用 HAL_ADC_ConvCpltCallback() 收集 50 个样本时,我正在切换 GPIO 引脚。
我的问题:定时器触发 ADC 启动、切换相应的 GPIO、获取 50 个样本然后再次切换 GPIO 需要 56us。虽然我预计由于使用 HAL 和切换引脚会出现 一些延迟,但我预计会在几微秒左右。以这种速度,我遇到了 50 个样本/56us = 893Ksps,大约是预期速度的一半。将分辨率降低到 10 位虽然有所不同,但并没有像它应该的那样大。所以出了点问题。
代码:
- int main(void)
- {
- HAL_Init();
- SystemClock_Config();
- MX_GPIO_Init();
- MX_DMA_Init();
- MX_ADC1_Init();
- MX_TIM2_Init();
- /* USER CODE BEGIN 2 */
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1);
- HAL_TIM_PWM_Start_IT(&htim2, TIM_CHANNEL_2);
- HAL_NVIC_SetPriority(TIM2_IRQn,15,0);
- HAL_NVIC_EnableIRQ(TIM2_IRQn);
- /* USER CODE END 2 */
- /* Infinite loop */
- /* USER CODE BEGIN WHILE */
- while (1)
- {
- /* USER CODE END WHILE */
- /* USER CODE BEGIN 3 */
- }
- /* USER CODE END 3 */
- }
- void SystemClock_Config(void)
- {
- RCC_OscInitTypeDef RCC_OscInitStruct = {0};
- RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
- /** Configure the main internal regulator output voltage
- */
- __HAL_RCC_PWR_CLK_ENABLE();
- __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
- /** Initializes the CPU, AHB and APB busses clocks
- */
- RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
- RCC_OscInitStruct.HSIState = RCC_HSI_ON;
- RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
- RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
- RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
- RCC_OscInitStruct.PLL.PLLM = 8;
- RCC_OscInitStruct.PLL.PLLN = 216;
- RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
- RCC_OscInitStruct.PLL.PLLQ = 4;
- if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
- {
- Error_Handler();
- }
- /** Activate the Over-Drive mode
- */
- if (HAL_PWREx_EnableOverDrive() != HAL_OK)
- {
- Error_Handler();
- }
- /** Initializes the CPU, AHB and APB busses clocks
- */
- RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
- |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
- RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
- RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
- RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
- RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
- if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_7) != HAL_OK)
- {
- Error_Handler();
- }
- }
- /**
- * @brief ADC1 Initialization Function
- * @param None
- * @retval None
- */
- 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 = ADC_SCAN_DISABLE;
- hadc1.Init.ContinuousConvMode = ENABLE;
- hadc1.Init.DiscontinuousConvMode = DISABLE;
- hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_RISING;
- hadc1.Init.ExternalTrigConv = ADC_EXTERNALTRIGCONV_T2_CC2;
- hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
- hadc1.Init.NbrOfConversion = 1;
- hadc1.Init.DMAContinuousRequests = ENABLE;
- hadc1.Init.EOCSelection = ADC_EOC_SEQ_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_3;
- sConfig.Rank = ADC_REGULAR_RANK_1;
- sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
- if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
- {
- Error_Handler();
- }
- /* USER CODE BEGIN ADC1_Init 2 */
- /* USER CODE END ADC1_Init 2 */
- }
- /**
- * @brief TIM2 Initialization Function
- * @param None
- * @retval None
- */
- static void MX_TIM2_Init(void)
- {
- /* USER CODE BEGIN TIM2_Init 0 */
- /* USER CODE END TIM2_Init 0 */
- TIM_MasterConfigTypeDef sMasterConfig = {0};
- TIM_OC_InitTypeDef sConfigOC = {0};
- /* USER CODE BEGIN TIM2_Init 1 */
- /* USER CODE END TIM2_Init 1 */
- htim2.Instance = TIM2;
- htim2.Init.Prescaler = 0;
- htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
- htim2.Init.Period = 20000;
- htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
- htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
- if (HAL_TIM_PWM_Init(&htim2) != HAL_OK)
- {
- Error_Handler();
- }
- sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
- sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
- if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
- {
- Error_Handler();
- }
- sConfigOC.OCMode = TIM_OCMODE_PWM1;
- sConfigOC.Pulse = 5000;
- sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
- sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
- if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
- {
- Error_Handler();
- }
- sConfigOC.Pulse = 7500;
- sConfigOC.OCPolarity = TIM_OCPOLARITY_LOW;
- if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
- {
- Error_Handler();
- }
- /* USER CODE BEGIN TIM2_Init 2 */
- /* USER CODE END TIM2_Init 2 */
- HAL_TIM_MspPostInit(&htim2);
- }
- /**
- * Enable DMA controller clock
- */
- static void MX_DMA_Init(void)
- {
- /* DMA controller clock enable */
- __HAL_RCC_DMA2_CLK_ENABLE();
- /* DMA interrupt init */
- /* DMA2_Stream0_IRQn interrupt configuration */
- HAL_NVIC_SetPriority(DMA2_Stream0_IRQn, 0, 0);
- HAL_NVIC_EnableIRQ(DMA2_Stream0_IRQn);
- }
- /* USER CODE BEGIN 4 */
- void HAL_TIM_PWM_PulseFinishedCallback(TIM_HandleTypeDef *htim)
- {
- if(htim->Channel == HAL_TIM_ACTIVE_CHANNEL_2)
- {
- GPIOB->ODR ^= (1 << 4);
- asm("NOP");
- }
- }
- void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc)
- {
- GPIOB->ODR ^= (1 << 4);
- GPIOA->ODR ^= (1 << 4);
- if(pulse_count == 0)
- {
- HAL_ADC_Stop_DMA(&hadc1);//, ADC_Val, sizeof(ADC_Val));
- memcpy(ADC_Total_1, ADC_Val, sizeof(ADC_Total_1));
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- pulse_count = 1;
- }
- else if(pulse_count == 1)
- {
- HAL_ADC_Stop_DMA(&hadc1);//, ADC_Val, sizeof(ADC_Val));
- memcpy(ADC_Total_2, ADC_Val, sizeof(ADC_Total_1));
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- pulse_count = 2;
- }
- else if(pulse_count == 2)
- {
- HAL_ADC_Stop_DMA(&hadc1);//, ADC_Val, sizeof(ADC_Val));
- memcpy(ADC_Total_3, ADC_Val, sizeof(ADC_Total_1));
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- pulse_count = 3;
- }
- else if(pulse_count == 3)
- {
- HAL_ADC_Stop_DMA(&hadc1);//, ADC_Val, sizeof(ADC_Val));
- memcpy(ADC_Total_4, ADC_Val, sizeof(ADC_Total_1));
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- pulse_count = 4 ;
- }
- else if(pulse_count == 4) {
- HAL_ADC_Stop_DMA(&hadc1);//, ADC_Val, sizeof(ADC_Val));
- memcpy(ADC_Total_5, ADC_Val, sizeof(ADC_Total_1));
- HAL_ADC_Start_DMA(&hadc1, ADC_Val, sizeof(ADC_Val));
- pulse_count = 0 ;
- }
- GPIOA->ODR ^= (1 << 4);
- asm("NOP");
- }
- void HAL_ADC_ConvHalfCpltCallback(ADC_HandleTypeDef* hadc)
- {
- //GPIOB->ODR ^= (1 << 4);
- }
我的设置代码有什么明显的错误吗?这很奇怪,因为我的计算和设置(至少对我而言)似乎是正确的。
0
|
|
1个回答
|
|
|
|