STM32外接RGB模块，实现按下按键，亮起一个灯，按下三次之后，所有灯熄灭

为了实现按下按键，亮起一个灯，按下三次之后，所有灯熄灭的效果，我们可以使用STM32的GPIO口和定时器模块来实现。具体步骤如下：

1. 首先需要配置GPIO口和定时器模块。我们可以使用TIM3和TIM4来分别控制外接的LED和开发板上的LED。其中，TIM3的输出口PA7连接外接的LED，TIM4的输出口PB7连接开发板上的LED。

2. 接下来，我们需要配置按键。可以使用STM32的外部中断模块来实现按键的检测。当按键按下时，触发外部中断，执行相应的操作。

3. 在程序中，我们可以使用一个计数器来记录按键按下的次数。当按键按下一次时，计数器加1。当计数器的值为3时，所有的LED都熄灭。

4. 在定时器中断服务函数中，我们可以通过改变PWM波形的占空比来实现LED的呼吸灯效果。当计数器的值为3时，将PWM波形的占空比设置为0，即可实现所有LED熄灭的效果。

下面是示例代码：

#include "stm32f10x.h"

#define LED_GPIO_PORT   GPIOB
#define LED_GPIO_PIN    GPIO_Pin_7

#define KEY_GPIO_PORT   GPIOA
#define KEY_GPIO_PIN    GPIO_Pin_0

#define PWM_GPIO_PORT   GPIOA
#define PWM_GPIO_PIN    GPIO_Pin_7

uint8_t key_count = 0;

void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    // 配置LED引脚
    GPIO_InitStructure.GPIO_Pin = LED_GPIO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(LED_GPIO_PORT, &GPIO_InitStructure);

    // 配置按键引脚
    GPIO_InitStructure.GPIO_Pin = KEY_GPIO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Init(KEY_GPIO_PORT, &GPIO_InitStructure);

    // 配置PWM引脚
    GPIO_InitStructure.GPIO_Pin = PWM_GPIO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(PWM_GPIO_PORT, &GPIO_InitStructure);
}

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

    // 配置TIM3
    TIM_TimeBaseStructure.TIM_Period = 999;
    TIM_TimeBaseStructure.TIM_Prescaler = 719;
    TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    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_OC1Init(TIM3, &TIM_OCInitStructure);

    TIM_Cmd(TIM3, ENABLE);

    // 配置TIM4
    TIM_TimeBaseStructure.TIM_Period = 999;
    TIM_TimeBaseStructure.TIM_Prescaler = 719;
    TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

    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_OC1Init(TIM4, &TIM_OCInitStructure);

    TIM_Cmd(TIM4, ENABLE);
}

void EXTI_Configuration(void)
{
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    // 配置外部中断
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);

    EXTI_InitStructure.EXTI_Line = EXTI_Line0;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line0);

        key_count++;

        if (key_count == 3)
        {
            TIM_SetCompare1(TIM3, 0);
            TIM_SetCompare1(TIM4, 0);
        }
    }
}

void TIM3_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)
    {
        TIM_ClearITPendingBit(TIM3, TIM_IT_Update);

        uint16_t duty_cycle = (TIM_GetCapture1(TIM3) + 1) % 1000;
        TIM_SetCompare1(TIM3, duty_cycle);
    }
}

void TIM4_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM4, TIM_IT_Update) != RESET)
    {
        TIM_ClearITPendingBit(TIM4, TIM_IT_Update);

        uint16_t duty_cycle = (TIM_GetCapture1(TIM4) + 1) % 1000;
        TIM_SetCompare1(TIM4, duty_cycle);
    }
}

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

    while (1)
    {
    }
}