编写一个基于stm32f429igtx的用光敏电阻和pwm控制led灯亮度的程序

以下是基于STM32F429IGTX的光敏电阻和PWM控制LED灯亮度的程序：

#include "stm32f4xx.h"

#define LED_PIN GPIO_Pin_13
#define LED_PORT GPIOG

#define PHOTO_PIN GPIO_Pin_0
#define PHOTO_PORT GPIOA

int main(void)
{
    GPIO_InitTypeDef GPIO_InitStruct;
    TIM_TimeBaseInitTypeDef TIM_InitStruct;
    TIM_OCInitTypeDef TIM_OC_InitStruct;
    ADC_InitTypeDef ADC_InitStruct;
    uint16_t adc_value = 0;

    // 使能时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOG, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

    // 配置LED
    GPIO_InitStruct.GPIO_Pin = LED_PIN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(LED_PORT, &GPIO_InitStruct);

    // 配置PWM定时器
    TIM_InitStruct.TIM_Prescaler = 84 - 1;
    TIM_InitStruct.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_InitStruct.TIM_Period = 100 - 1;
    TIM_InitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInit(TIM2, &TIM_InitStruct);

    // 配置PWM输出通道
    TIM_OC_InitStruct.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OC_InitStruct.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OC_InitStruct.TIM_Pulse = 0;
    TIM_OC_InitStruct.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC1Init(TIM2, &TIM_OC_InitStruct);
    TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);

    // 配置光敏电阻
    GPIO_InitStruct.GPIO_Pin = PHOTO_PIN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_Init(PHOTO_PORT, &GPIO_InitStruct);

    // 配置ADC
    ADC_InitStruct.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStruct.ADC_ScanConvMode = DISABLE;
    ADC_InitStruct.ADC_ContinuousConvMode = ENABLE;
    ADC_InitStruct.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStruct.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStruct.ADC_NbrOfConversion = 1;
    ADC_Init(ADC1, &ADC_InitStruct);

    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_15Cycles);

    // 启动ADC
    ADC_Cmd(ADC1, ENABLE);
    while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_ADEN));

    // 启动PWM
    TIM_Cmd(TIM2, ENABLE);

    while (1)
    {
        // 获取光敏电阻值
        ADC_SoftwareStartConv(ADC1);
        while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC));
        adc_value = ADC_GetConversionValue(ADC1);

        // 根据光敏电阻值调整LED亮度
        TIM_SetCompare1(TIM2, adc_value * 100 / 4095);
    }
}

该程序使用PA0作为光敏电阻输入，PG13作为LED输出。通过定时器PWM控制LED亮度，通过ADC获取光敏电阻的值，并将其转换为占空比控制LED亮度的亮度。