目录
项目需求
项目框图
编辑
硬件清单
sg90舵机介绍及实战
sg90舵机介绍
角度控制
SG90舵机编程实现
超声波传感器介绍及实战
超声波传感器介绍
超声波编程实战
项目设计及实现
项目需求
- 检测靠近时,垃圾桶自动开盖并伴随滴一声,2秒后关盖
- 发生震动时,垃圾桶自动开盖并伴随滴一声,2秒后关盖
- 按下按键时,垃圾桶自动开盖并伴随滴一声,2秒后关盖
项目框图
硬件清单
SG90
舵机,超声波模块,震动传感器,蜂鸣器
sg90舵机介绍及实战
sg90舵机介绍
PWM波的频率不能太高,大约50HZ,即周期=1/频率=1/50=0.02s,20ms左右。
确定周期/频率
如果周期为20ms,则 PSC=7199,ARR=199
角度控制
- 0.5ms-------------0度; 2.5% 对应函数中CCRx为5
- 1.0ms------------45度; 5.0% 对应函数中CCRx为10
- 1.5ms------------90度; 7.5% 对应函数中CCRx为15
- 2.0ms-----------135度; 10.0% 对应函数中CCRx为20
- 2.5ms-----------180度; 12.5% 对应函数中CCRx为25
SG90舵机编程实现
需求:
每隔
1s
,转动一个角度:
0
度
--> 45
度
--> 90
度
--> 135
度
--> 180
度
--> 0
度
接线:
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HAL_TIM_PWM_Start(&htim4,TIM_CHANNEL_3);
while (1)
{
HAL_Delay(1000);
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_3, 5);
HAL_Delay(1000);
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_3, 10);
HAL_Delay(1000);
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_3, 15);
HAL_Delay(1000);
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_3, 20);
HAL_Delay(1000);
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_3, 25);
}
超声波传感器介绍及实战
超声波传感器介绍
- 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
超声波编程实战
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。
接线:
Trig --- PB6
Echo --- PB7
LED1 --- PB8
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定时器配置:
使用
TIM2
,只用作计数功能,不用作定时。
将
PSC
配置为
71
,则计数
1
次代表
1us
。
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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);
}
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
(计数
1
次表示
1us
)
//
每
500
毫秒测试一次距离
int cnt;
float distance;
while (1)
{
//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1us)
distance = cnt*340/2*0.000001*100; //单位:cm
if(distance < 5)
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_RESET);
else
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);
//每500毫秒测试一次距离
HAL_Delay(500);
}
项目设计及实现
项目设计
超声波模块:
Trig -- PB6
Echo -- PB7
sg90
舵机:
PWM -- PB9
按键:
KEY1 -- PA0
LED
灯:
LED1 -- PB8
震动传感器:
D0 -- PB5
VCC -- 5V
蜂鸣器:
IO -- PB4
VCC -- 3V3
/* 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"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
#define OPEN 1
#define CLOSE 0
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
char flag=CLOSE;
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim2;
TIM_HandleTypeDef htim4;
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);
static void MX_TIM4_Init(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);
}
double get_distance()
{
int cnt;
//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1us)
return (cnt*340/2*0.000001*100); //单位:cm
}
void openStatusLight()
{
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_RESET);
}
void closeStatusLight()
{
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);
}
void initSG90_0()
{
HAL_TIM_PWM_Start(&htim4,TIM_CHANNEL_4);//启动定时器4
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_4, 5);//将舵机置0°
}
void openDusbin()
{
if(flag==CLOSE){
flag=OPEN;
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_4, 15);//将舵机置90°
HAL_GPIO_WritePin(GPIOB,GPIO_PIN_4,GPIO_PIN_RESET);
HAL_Delay(100);
HAL_GPIO_WritePin(GPIOB,GPIO_PIN_4,GPIO_PIN_SET);
}
HAL_Delay(2000);
}
void closeDusbin()
{
__HAL_TIM_SetCompare(&htim4, TIM_CHANNEL_4, 5);//将舵机置0°
flag=CLOSE;
HAL_Delay(150);
}
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
if(GPIO_Pin==GPIO_PIN_0||GPIO_Pin==GPIO_PIN_5){
if(HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0)==GPIO_PIN_RESET ||
HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_5)==GPIO_PIN_RESET){
openStatusLight();
openDusbin();
}
}
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
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();
MX_TIM4_Init();
/* USER CODE BEGIN 2 */
initSG90_0();
HAL_NVIC_SetPriority(SysTick_IRQn,0,0);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
//超声波测距
distance=get_distance();
if(distance < 10){
openStatusLight();
//开盖
openDusbin();
}
else{
closeStatusLight();
//关盖
closeDusbin();
}
}
/* 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();
}
}
/**
* @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_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 */
}
/**
* @brief TIM4 Initialization Function
* @param None
* @retval None
*/
static void MX_TIM4_Init(void)
{
/* USER CODE BEGIN TIM4_Init 0 */
/* USER CODE END TIM4_Init 0 */
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
/* USER CODE BEGIN TIM4_Init 1 */
/* USER CODE END TIM4_Init 1 */
htim4.Instance = TIM4;
htim4.Init.Prescaler = 7199;
htim4.Init.CounterMode = TIM_COUNTERMODE_UP;
htim4.Init.Period = 199;
htim4.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim4.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
if (HAL_TIM_Base_Init(&htim4) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim4, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_TIM_PWM_Init(&htim4) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim4, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
if (HAL_TIM_PWM_ConfigChannel(&htim4, &sConfigOC, TIM_CHANNEL_4) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN TIM4_Init 2 */
/* USER CODE END TIM4_Init 2 */
HAL_TIM_MspPostInit(&htim4);
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static 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_4|GPIO_PIN_8, GPIO_PIN_SET);
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6, GPIO_PIN_RESET);
/*Configure GPIO pin : PA0 */
GPIO_InitStruct.Pin = GPIO_PIN_0;
GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/*Configure GPIO pins : PB4 PB6 PB8 */
GPIO_InitStruct.Pin = GPIO_PIN_4|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 : PB5 */
GPIO_InitStruct.Pin = GPIO_PIN_5;
GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
GPIO_InitStruct.Pull = GPIO_NOPULL;
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);
/* EXTI interrupt init*/
HAL_NVIC_SetPriority(EXTI0_IRQn, 2, 0);
HAL_NVIC_EnableIRQ(EXTI0_IRQn);
HAL_NVIC_SetPriority(EXTI9_5_IRQn, 2, 0);
HAL_NVIC_EnableIRQ(EXTI9_5_IRQn);
}
/* 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 */