网站建设简历模板,哔哩哔哩网站电子商务建设,论文格式样板模板,郑州经济技术开发区实验中学一#xff1a;超声波传感器介绍
1.1、SR04超声波测距硬件模块 1.2、SR04的四个IO口
vcc:提供电源5V
gnd:接地
Trig:是**发送**声波信号的触发器
Echo:是**接收**回波信号的引脚
当TRIG信号被触发时#xff0c;传感器会发送一定频率的声波信号#xff0c;该信号被反射后超声波传感器介绍
1.1、SR04超声波测距硬件模块 1.2、SR04的四个IO口
vcc:提供电源5V
gnd:接地
Trig:是**发送**声波信号的触发器
Echo:是**接收**回波信号的引脚
当TRIG信号被触发时传感器会发送一定频率的声波信号该信号被反射后传感器会接收到回波信号回波信号的时间差可以用来计算物体与传感器的距离。1.3、SR04是高电平触发模块
所以默认是低电平 怎么让它发送波 Trig 给Trig端口至少10us的高电平 怎么知道它开始发了 Echo信号由低电平跳转到高电平表示开始发送波 怎么知道接收了返回波 Echo由高电平跳转回低电平表示波回来了 怎么算时间 Echo引脚维持高电平的时间
波发出去的那一下开始启动定时器 波回来的拿一下我们开始停止定时器计算出中间经过多少时间 怎么算距离 距离 速度 340m/s* 时间/2
二、需求介绍
2.1、SR04超声波测距需求介绍
需求使用超声波测距当手离传感器距离小于5cm时LED1点亮否则保持不亮状态。
2.2、SR04超声波测距模块接线 Trig — PB6 Echo — PB7 LED1 — PB8
三stm32CubeMX实现步骤以及细节
3.1、打开Stm32CubeMX,界面如图 3.2、选芯片stm32f103c8t6 3.3、读芯片引脚原理图 3.4、先把LED灯设置为高电平模式
3.5、设置时钟
配置时钟频率
3.6、RCC配置 3.7、定时器
计数一次代表1us
Tout就是一次的溢出时间PSC71,Tclk72000 000hz(s),此处ARR0
3.8、代码自动设置生成的文件 3.9、图形化最后一步
项目名称sr04_study 四编写业务代码
4.1、在初始化完成的代码之后添加业务代码
第①处增加的代码编写微秒级函数
//使用TIM2来做us级延时函数
void TIM2_Delay_us(uint16_t n_us)
{
/* 使能定时器2计数 */
__HAL_TIM_ENABLE(htim2);
__HAL_TIM_SetCounter(htim2, 0);
while(__HAL_TIM_GetCounter(htim2) ((1 * n_us)-1) );
/* 关闭定时器2计数 */
__HAL_TIM_DISABLE(htim2);
}4.2、定义变量
第②处增加的代码 /* USER CODE BEGIN 1 */int cnt;float distance;/* USER CODE END 1 */4.3、主函数
//1. Trig 给Trig端口至少10us的高电平 //2. echo由低电平跳转到高电平表示开始发送波 //波发出去的那一下开始启动定时器 //3. 由高电平跳转回低电平表示波回来了 //波回来的那一下我们开始停止定时器 //4. 计算出中间经过多少时间 //5. 距离 速度 340m/s* 时间/2注意单位换算 计数1次表示1us //每500毫秒测试一次距离
第③处增加的代码
while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 *///1. Trig 给Trig端口至少10us的高电平HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_SET);//拉高TIM2_Delay_us(20);HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET);//拉低//2. echo由低电平跳转到高电平表示开始发送波//波发出去的那一下开始启动定时器while(HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7) GPIO_PIN_RESET);//等待输入电平拉高HAL_TIM_Base_Start(htim2);__HAL_TIM_SetCounter(htim2,0);//3. 由高电平跳转回低电平表示波回来了while(HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7) GPIO_PIN_SET);//等待输入电平变低//波回来的那一下我们开始停止定时器HAL_TIM_Base_Stop(htim2);//4. 计算出中间经过多少时间cnt __HAL_TIM_GetCounter(htim2);//5. 距离 速度 340m/s* 时间/2计数1次表示1usdistance cnt*340/2*0.000001*100; //单位cm//2*0.000001表示了发送和接收时间的差值单位为秒,*100是把米变成厘米if(distance 5)HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_RESET);elseHAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);//每500毫秒测试一次距离HAL_Delay(500);}/* USER CODE END 3 */
}4.4、main.c总代码直接复制可用
只有main.c有增加下面的gpio.c、tim.c等等文件都没有变动
/* USER CODE BEGIN Header */
/********************************************************************************* file : main.c* brief : Main program body******************************************************************************* attention** Copyright (c) 2023 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include main.h
#include tim.h
#include gpio.h/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes *//* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD *//* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *///使用TIM2来做us级延时函数void TIM2_Delay_us(uint16_t n_us){/* 使能定时器2计数 */__HAL_TIM_ENABLE(htim2);__HAL_TIM_SetCounter(htim2, 0);while(__HAL_TIM_GetCounter(htim2) ((1 * n_us)-1) );/* 关闭定时器2计数 */__HAL_TIM_DISABLE(htim2);}
/* USER CODE END 0 *//*** brief The application entry point.* retval int*/
int main(void)
{/* USER CODE BEGIN 1 */int cnt;float distance;/* 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_TIM2_Init();/* USER CODE BEGIN 2 *//* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 *///1. Trig 给Trig端口至少10us的高电平HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_SET);//拉高TIM2_Delay_us(20);HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET);//拉低//2. echo由低电平跳转到高电平表示开始发送波//波发出去的那一下开始启动定时器while(HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7) GPIO_PIN_RESET);//等待输入电平拉高HAL_TIM_Base_Start(htim2);__HAL_TIM_SetCounter(htim2,0);//3. 由高电平跳转回低电平表示波回来了while(HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7) GPIO_PIN_SET);//等待输入电平变低//波回来的那一下我们开始停止定时器HAL_TIM_Base_Stop(htim2);//4. 计算出中间经过多少时间cnt __HAL_TIM_GetCounter(htim2);//5. 距离 速度 340m/s* 时间/2计数1次表示1usdistance cnt*340/2*0.000001*100; //单位cm//2*0.000001表示了发送和接收时间的差值单位为秒,*100是把米变成厘米if(distance 5)HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_RESET);elseHAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);//每500毫秒测试一次距离HAL_Delay(500);}/* USER CODE END 3 */
}/*** brief System Clock Configuration* retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct {0};RCC_ClkInitTypeDef RCC_ClkInitStruct {0};/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState RCC_HSE_ON;RCC_OscInitStruct.HSEPredivValue RCC_HSE_PREDIV_DIV1;RCC_OscInitStruct.HSIState RCC_HSI_ON;RCC_OscInitStruct.PLL.PLLState RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLMUL RCC_PLL_MUL9;if (HAL_RCC_OscConfig(RCC_OscInitStruct) ! HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses 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_DIV2;RCC_ClkInitStruct.APB2CLKDivider RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(RCC_ClkInitStruct, FLASH_LATENCY_2) ! HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 *//* USER CODE END 4 *//*** brief This function is executed in case of error occurrence.* retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef USE_FULL_ASSERT
/*** brief Reports the name of the source file and the source line number* where the assert_param error has occurred.* param file: pointer to the source file name* param line: assert_param error line source number* retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf(Wrong parameters value: file %s on line %d\r\n, file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
4.5、gpio.c
/* USER CODE BEGIN Header */
/********************************************************************************* file gpio.c* brief This file provides code for the configuration* of all used GPIO pins.******************************************************************************* attention** Copyright (c) 2023 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header *//* Includes ------------------------------------------------------------------*/
#include gpio.h/* USER CODE BEGIN 0 *//* USER CODE END 0 *//*----------------------------------------------------------------------------*/
/* Configure GPIO */
/*----------------------------------------------------------------------------*/
/* USER CODE BEGIN 1 *//* USER CODE END 1 *//** Configure pins as* Analog* Input* Output* EVENT_OUT* EXTI
*/
void MX_GPIO_Init(void)
{GPIO_InitTypeDef GPIO_InitStruct {0};/* GPIO Ports Clock Enable */__HAL_RCC_GPIOD_CLK_ENABLE();__HAL_RCC_GPIOA_CLK_ENABLE();__HAL_RCC_GPIOB_CLK_ENABLE();/*Configure GPIO pin Output Level */HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET);/*Configure GPIO pin Output Level */HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);/*Configure GPIO pins : PB6 PB8 */GPIO_InitStruct.Pin GPIO_PIN_6|GPIO_PIN_8;GPIO_InitStruct.Mode GPIO_MODE_OUTPUT_PP;GPIO_InitStruct.Pull GPIO_NOPULL;GPIO_InitStruct.Speed GPIO_SPEED_FREQ_LOW;HAL_GPIO_Init(GPIOB, GPIO_InitStruct);/*Configure GPIO pin : PB7 */GPIO_InitStruct.Pin GPIO_PIN_7;GPIO_InitStruct.Mode GPIO_MODE_INPUT;GPIO_InitStruct.Pull GPIO_NOPULL;HAL_GPIO_Init(GPIOB, GPIO_InitStruct);}/* USER CODE BEGIN 2 *//* USER CODE END 2 */
4.6、tim.c
/* USER CODE BEGIN Header */
/********************************************************************************* file tim.c* brief This file provides code for the configuration* of the TIM instances.******************************************************************************* attention** Copyright (c) 2023 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include tim.h/* USER CODE BEGIN 0 *//* USER CODE END 0 */TIM_HandleTypeDef htim2;/* TIM2 init function */
void MX_TIM2_Init(void)
{/* USER CODE BEGIN TIM2_Init 0 *//* USER CODE END TIM2_Init 0 */TIM_ClockConfigTypeDef sClockSourceConfig {0};TIM_MasterConfigTypeDef sMasterConfig {0};/* USER CODE BEGIN TIM2_Init 1 *//* USER CODE END TIM2_Init 1 */htim2.Instance TIM2;htim2.Init.Prescaler 71;htim2.Init.CounterMode TIM_COUNTERMODE_UP;htim2.Init.Period 65535;htim2.Init.ClockDivision TIM_CLOCKDIVISION_DIV1;htim2.Init.AutoReloadPreload TIM_AUTORELOAD_PRELOAD_ENABLE;if (HAL_TIM_Base_Init(htim2) ! HAL_OK){Error_Handler();}sClockSourceConfig.ClockSource TIM_CLOCKSOURCE_INTERNAL;if (HAL_TIM_ConfigClockSource(htim2, sClockSourceConfig) ! HAL_OK){Error_Handler();}sMasterConfig.MasterOutputTrigger TIM_TRGO_RESET;sMasterConfig.MasterSlaveMode TIM_MASTERSLAVEMODE_DISABLE;if (HAL_TIMEx_MasterConfigSynchronization(htim2, sMasterConfig) ! HAL_OK){Error_Handler();}/* USER CODE BEGIN TIM2_Init 2 *//* USER CODE END TIM2_Init 2 */}void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{if(tim_baseHandle-InstanceTIM2){/* USER CODE BEGIN TIM2_MspInit 0 *//* USER CODE END TIM2_MspInit 0 *//* TIM2 clock enable */__HAL_RCC_TIM2_CLK_ENABLE();/* USER CODE BEGIN TIM2_MspInit 1 *//* USER CODE END TIM2_MspInit 1 */}
}void HAL_TIM_Base_MspDeInit(TIM_HandleTypeDef* tim_baseHandle)
{if(tim_baseHandle-InstanceTIM2){/* USER CODE BEGIN TIM2_MspDeInit 0 *//* USER CODE END TIM2_MspDeInit 0 *//* Peripheral clock disable */__HAL_RCC_TIM2_CLK_DISABLE();/* USER CODE BEGIN TIM2_MspDeInit 1 *//* USER CODE END TIM2_MspDeInit 1 */}
}/* USER CODE BEGIN 1 *//* USER CODE END 1 */
4.7、stm32f1xx_it.c
/* USER CODE BEGIN Header */
/********************************************************************************* file stm32f1xx_it.c* brief Interrupt Service Routines.******************************************************************************* attention** Copyright (c) 2023 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header *//* Includes ------------------------------------------------------------------*/
#include main.h
#include stm32f1xx_it.h
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN TD *//* USER CODE END TD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD *//* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *//* USER CODE END 0 *//* External variables --------------------------------------------------------*//* USER CODE BEGIN EV *//* USER CODE END EV *//******************************************************************************/
/* Cortex-M3 Processor Interruption and Exception Handlers */
/******************************************************************************/
/*** brief This function handles Non maskable interrupt.*/
void NMI_Handler(void)
{/* USER CODE BEGIN NonMaskableInt_IRQn 0 *//* USER CODE END NonMaskableInt_IRQn 0 *//* USER CODE BEGIN NonMaskableInt_IRQn 1 */while (1){}/* USER CODE END NonMaskableInt_IRQn 1 */
}/*** brief This function handles Hard fault interrupt.*/
void HardFault_Handler(void)
{/* USER CODE BEGIN HardFault_IRQn 0 *//* USER CODE END HardFault_IRQn 0 */while (1){/* USER CODE BEGIN W1_HardFault_IRQn 0 *//* USER CODE END W1_HardFault_IRQn 0 */}
}/*** brief This function handles Memory management fault.*/
void MemManage_Handler(void)
{/* USER CODE BEGIN MemoryManagement_IRQn 0 *//* USER CODE END MemoryManagement_IRQn 0 */while (1){/* USER CODE BEGIN W1_MemoryManagement_IRQn 0 *//* USER CODE END W1_MemoryManagement_IRQn 0 */}
}/*** brief This function handles Prefetch fault, memory access fault.*/
void BusFault_Handler(void)
{/* USER CODE BEGIN BusFault_IRQn 0 *//* USER CODE END BusFault_IRQn 0 */while (1){/* USER CODE BEGIN W1_BusFault_IRQn 0 *//* USER CODE END W1_BusFault_IRQn 0 */}
}/*** brief This function handles Undefined instruction or illegal state.*/
void UsageFault_Handler(void)
{/* USER CODE BEGIN UsageFault_IRQn 0 *//* USER CODE END UsageFault_IRQn 0 */while (1){/* USER CODE BEGIN W1_UsageFault_IRQn 0 *//* USER CODE END W1_UsageFault_IRQn 0 */}
}/*** brief This function handles System service call via SWI instruction.*/
void SVC_Handler(void)
{/* USER CODE BEGIN SVCall_IRQn 0 *//* USER CODE END SVCall_IRQn 0 *//* USER CODE BEGIN SVCall_IRQn 1 *//* USER CODE END SVCall_IRQn 1 */
}/*** brief This function handles Debug monitor.*/
void DebugMon_Handler(void)
{/* USER CODE BEGIN DebugMonitor_IRQn 0 *//* USER CODE END DebugMonitor_IRQn 0 *//* USER CODE BEGIN DebugMonitor_IRQn 1 *//* USER CODE END DebugMonitor_IRQn 1 */
}/*** brief This function handles Pendable request for system service.*/
void PendSV_Handler(void)
{/* USER CODE BEGIN PendSV_IRQn 0 *//* USER CODE END PendSV_IRQn 0 *//* USER CODE BEGIN PendSV_IRQn 1 *//* USER CODE END PendSV_IRQn 1 */
}/*** brief This function handles System tick timer.*/
void SysTick_Handler(void)
{/* USER CODE BEGIN SysTick_IRQn 0 *//* USER CODE END SysTick_IRQn 0 */HAL_IncTick();/* USER CODE BEGIN SysTick_IRQn 1 *//* USER CODE END SysTick_IRQn 1 */
}/******************************************************************************/
/* STM32F1xx Peripheral Interrupt Handlers */
/* Add here the Interrupt Handlers for the used peripherals. */
/* For the available peripheral interrupt handler names, */
/* please refer to the startup file (startup_stm32f1xx.s). */
/******************************************************************************//* USER CODE BEGIN 1 *//* USER CODE END 1 */
4.8、超声波测距效果
1.代码编译烧录之后 2.测试超声波测距 把手放在距离sr04 5cm以内led灯会亮再远灯会灭 以上完
