stm32用按键控制灯的亮度

以下是使用STM32的PWM模块和按键控制LED灯亮度的代码示例：

#include "stm32f10x.h"

#define LED_PIN GPIO_Pin_13
#define LED_PORT GPIOC

#define KEY1_PIN GPIO_Pin_0
#define KEY2_PIN GPIO_Pin_1
#define KEY3_PIN GPIO_Pin_2
#define KEY4_PIN GPIO_Pin_3
#define KEY5_PIN GPIO_Pin_4
#define KEY6_PIN GPIO_Pin_5
#define KEY_PORT GPIOA

#define PWM_PIN GPIO_Pin_0
#define PWM_PORT GPIOB
#define PWM_CHANNEL TIM_Channel_3
#define PWM_TIMER TIM4

void GPIO_Configuration(void);
void TIM_Configuration(void);
void NVIC_Configuration(void);

int main(void)
{
    GPIO_Configuration();
    TIM_Configuration();
    NVIC_Configuration();

    while (1)
    {
        // 按键检测
        if (GPIO_ReadInputDataBit(KEY_PORT, KEY1_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 1000); // 占空比为 10%
        }
        else if (GPIO_ReadInputDataBit(KEY_PORT, KEY2_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 2000); // 占空比为 20%
        }
        else if (GPIO_ReadInputDataBit(KEY_PORT, KEY3_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 3000); // 占空比为 30%
        }
        else if (GPIO_ReadInputDataBit(KEY_PORT, KEY4_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 4000); // 占空比为 40%
        }
        else if (GPIO_ReadInputDataBit(KEY_PORT, KEY5_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 5000); // 占空比为 50%
        }
        else if (GPIO_ReadInputDataBit(KEY_PORT, KEY6_PIN) == 0)
        {
            TIM_SetCompare3(PWM_TIMER, 6000); // 占空比为 60%
        }
    }
}

void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    // LED 灯引脚配置
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
    GPIO_InitStructure.GPIO_Pin = LED_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(LED_PORT, &GPIO_InitStructure);

    // 按键引脚配置
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    GPIO_InitStructure.GPIO_Pin = KEY1_PIN | KEY2_PIN | KEY3_PIN | KEY4_PIN | KEY5_PIN | KEY6_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(KEY_PORT, &GPIO_InitStructure);

    // PWM 引脚配置
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
    GPIO_InitStructure.GPIO_Pin = PWM_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(PWM_PORT, &GPIO_InitStructure);
}

void TIM_Configuration(void)
{
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

    // 定时器时钟配置
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);

    // 定时器基本配置
    TIM_TimeBaseStructure.TIM_Period = 7199; // 定时器周期为 72MHz / 7200 = 10kHz
    TIM_TimeBaseStructure.TIM_Prescaler = 0;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(PWM_TIMER, &TIM_TimeBaseStructure);

    // PWM 配置
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 0;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC3Init(PWM_TIMER, &TIM_OCInitStructure);
    TIM_OC3PreloadConfig(PWM_TIMER, TIM_OCPreload_Enable);

    // 定时器启动
    TIM_Cmd(PWM_TIMER, ENABLE);
}

void NVIC_Configuration(void)
{
    NVIC_InitTypeDef NVIC_InitStructure;

    // 按键中断配置
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

// 按键中断处理函数
void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}

void EXTI1_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line1) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line1);
    }
}

void EXTI2_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line2) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line2);
    }
}

void EXTI3_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line3) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line3);
    }
}

void EXTI4_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line4) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line4);
    }
}

void EXTI9_5_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line5) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line5);
    }
}

该代码使用了STM32的定时器模块和GPIO模块，通过按键检测来改变PWM波的占空比，从而控制LED灯的亮度。具体实现过程如下：

1. 配置LED灯引脚和按键引脚为输出和输入模式，配置PWM引脚为复用推挽输出模式。
2. 配置定时器模块，设置定时器周期为10kHz，PWM模式为PWM1模式，输出极性为高电平。
3. 在主函数中循环检测按键状态，根据按键状态设置PWM波的占空比，从而控制LED灯的亮度。
4. 配置按键中断，但是该代码并没有使用中断处理函数。