STM32F103RCTx的PWM输出控制电机

发布于:2025-07-09 ⋅ 阅读:(25) ⋅ 点赞:(0)

关键功能说明

  1. PWM配置

    • 使用TIM1生成500Hz PWM信号

    • 输出引脚:PA8 (TIM1_CH1)

    • 计数器设置:预分频72-1 (1MHz时钟),周期1999 (500Hz)

    • 初始占空比:50% (CCR=1000)

  2. 按键处理

    • 使用TIM2定时器中断实现按键扫描(10ms间隔)

    • UP键(PA0):增加占空比

    • DOWN键(PA1):减少占空比

    • 按键消抖:30ms确认按下(3次扫描)

    • 长按支持:按键保持按下时,每200ms触发一次调整

  3. 工作流程

    • 系统初始化后启动PWM输出

    • TIM2每10ms触发中断扫描按键状态

    • 检测到按键按下时设置标志位

    • 在定时器中断中更新PWM占空比

    • 主循环处于低功耗状态(HAL_Delay)

硬件连接

MCU引脚 功能 连接目标
PA8 TIM1_CH1 电机驱动PWM输入
PA0 GPIO输入 UP按键(接GND)
PA1 GPIO输入 DOWN按键(接GND)
GND 按键和电机共地

功能特点

  1. 精确的PWM控制

    • 500Hz PWM频率,适合多数直流电机控制

    • 占空比范围:0-1999 (0-100%)

    • 步进调整:10% (200步进值)

  2. 可靠的按键处理

    • 定时器中断扫描确保实时性

    • 30ms消抖时间防止误触发

    • 支持短按和长按操作

  3. 优化的系统结构

    • 中断处理保持主循环简洁

    • HAL库提供硬件抽象层

    • 低功耗设计(主循环使用HAL_Delay)

使用说明

  1. 在STM32CubeIDE中创建工程

  2. 复制代码到main.c

  3. 配置TIM1为PWM输出,TIM2为基本定时器

  4. 配置PA0和PA1为输入模式

  5. 编译并烧录到STM32F103RC开发板

  6. 按UP/DOWN键调整电机速度

#include "stm32f1xx_hal.h"

// 全局变量
TIM_HandleTypeDef htim1;
TIM_HandleTypeDef htim2;
volatile uint16_t pwm_duty = 1000;  // 初始占空比50%(ARR=1999)
volatile uint8_t key_up_flag = 0;
volatile uint8_t key_down_flag = 0;

// 系统时钟配置
void SystemClock_Config(void) {
    RCC_OscInitTypeDef osc = {0};
    RCC_ClkInitTypeDef clk = {0};
    
    osc.OscillatorType = RCC_OSCILLATORTYPE_HSE;
    osc.HSEState = RCC_HSE_ON;
    osc.PLL.PLLState = RCC_PLL_ON;
    osc.PLL.PLLSource = RCC_PLLSOURCE_HSE;
    osc.PLL.PLLMUL = RCC_PLL_MUL9;
    HAL_RCC_OscConfig(&osc);
    
    clk.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                  |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
    clk.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    clk.AHBCLKDivider = RCC_SYSCLK_DIV1;
    clk.APB1CLKDivider = RCC_HCLK_DIV2;
    clk.APB2CLKDivider = RCC_HCLK_DIV1;
    HAL_RCC_ClockConfig(&clk, FLASH_LATENCY_2);
}

// TIM1 PWM初始化 (500Hz)
void MX_TIM1_Init(void) {
    TIM_ClockConfigTypeDef sClockSourceConfig = {0};
    TIM_MasterConfigTypeDef sMasterConfig = {0};
    TIM_OC_InitTypeDef sConfigOC = {0};
    TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};

    htim1.Instance = TIM1;
    htim1.Init.Prescaler = 72 - 1;          // 72MHz/72 = 1MHz
    htim1.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim1.Init.Period = 1999;                // 1MHz/2000 = 500Hz
    htim1.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
    htim1.Init.RepetitionCounter = 0;
    htim1.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
    HAL_TIM_Base_Init(&htim1);
    
    sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
    HAL_TIM_ConfigClockSource(&htim1, &sClockSourceConfig);
    
    HAL_TIM_PWM_Init(&htim1);
    
    sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
    sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
    HAL_TIMEx_MasterConfigSynchronization(&htim1, &sMasterConfig);
    
    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = pwm_duty;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
    sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
    HAL_TIM_PWM_ConfigChannel(&htim1, &sConfigOC, TIM_CHANNEL_1);
    
    sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
    sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
    sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
    sBreakDeadTimeConfig.DeadTime = 0;
    sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
    sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
    sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
    HAL_TIMEx_ConfigBreakDeadTime(&htim1, &sBreakDeadTimeConfig);

    // GPIO配置
    GPIO_InitTypeDef GPIO_InitStruct = {0};
    __HAL_RCC_GPIOA_CLK_ENABLE();
    GPIO_InitStruct.Pin = GPIO_PIN_8;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
    
    // 启动PWM
    HAL_TIM_PWM_Start(&htim1, TIM_CHANNEL_1);
    __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_1, pwm_duty);
    HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_1);
    __HAL_TIM_MOE_ENABLE(&htim1);
}

// TIM2 按键扫描定时器初始化 (10ms中断)
void MX_TIM2_Init(void) {
    htim2.Instance = TIM2;
    htim2.Init.Prescaler = 7200 - 1;      // 72MHz/7200 = 10KHz
    htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim2.Init.Period = 100 - 1;          // 10KHz/100 = 100Hz (10ms)
    htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
    htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
    HAL_TIM_Base_Init(&htim2);
    
    HAL_TIM_Base_Start_IT(&htim2);
}

// GPIO初始化
void MX_GPIO_Init(void) {
    // 按键配置 (PA0, PA1)
    GPIO_InitTypeDef GPIO_InitStruct = {0};
    __HAL_RCC_GPIOA_CLK_ENABLE();
    
    // UP键 (PA0)
    GPIO_InitStruct.Pin = GPIO_PIN_0;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_PULLUP;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
    
    // DOWN键 (PA1)
    GPIO_InitStruct.Pin = GPIO_PIN_1;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

// 按键扫描函数 (10ms调用一次)
void Key_Scan(void) {
    static uint8_t up_key_cnt = 0;
    static uint8_t down_key_cnt = 0;
    
    // UP键扫描
    if (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_0) == GPIO_PIN_RESET) {
        if (up_key_cnt < 20) up_key_cnt++; // 20*10ms = 200ms消抖+确认
        if (up_key_cnt == 3) {            // 30ms消抖后确认按下
            key_up_flag = 1;
        }
    } else {
        up_key_cnt = 0;
    }
    
    // DOWN键扫描
    if (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_1) == GPIO_PIN_RESET) {
        if (down_key_cnt < 20) down_key_cnt++;
        if (down_key_cnt == 3) {
            key_down_flag = 1;
        }
    } else {
        down_key_cnt = 0;
    }
}

// 定时器中断回调
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim) {
    if (htim->Instance == TIM2) {
        Key_Scan(); // 每10ms扫描一次按键
        
        // 处理UP键
        if (key_up_flag) {
            if (pwm_duty < 1900) pwm_duty += 100; // 增加10%占空比
            __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_1, pwm_duty);
            key_up_flag = 0;
        }
        
        // 处理DOWN键
        if (key_down_flag) {
            if (pwm_duty > 100) pwm_duty -= 100; // 减少10%占空比
            __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_1, pwm_duty);
            key_down_flag = 0;
        }
    }
}

int main(void) {
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    MX_TIM1_Init();
    MX_TIM2_Init();
    
    while (1) {
        // 主循环可添加其他任务
        HAL_Delay(100);
    }
}

// 中断处理函数
void TIM2_IRQHandler(void) {
    HAL_TIM_IRQHandler(&htim2);
}


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