stm32pwm输出标准库

以下是使用STM32标准库进行PWM输出的示例代码。假设我们要使用TIM3通道1来输出PWM信号，具体步骤如下：

1. 配置GPIO引脚为PWM输出模式

GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //PWM输出引脚
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

2. 配置TIM3为PWM输出模式

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;

//使能TIM3时钟
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

//配置TIM3时基
TIM_TimeBaseStructure.TIM_Period = 999; //PWM周期
TIM_TimeBaseStructure.TIM_Prescaler = 71; //时钟预分频
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

//配置TIM3通道1为PWM输出模式
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 499; //PWM占空比
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC1Init(TIM3, &TIM_OCInitStructure);

//使能TIM3
TIM_Cmd(TIM3, ENABLE);

在上述代码中，我们将TIM3的时基配置为1000Hz，即PWM周期为1毫秒。同时，我们将TIM3通道1的占空比设置为50%，即PWM脉冲高电平持续500微秒，低电平持续500微秒。

注意，在使用PWM输出之前，需要先使能相应引脚和定时器的时钟。上述代码中，我们使用了GPIOA和TIM3，因此需要在main函数中添加以下代码：

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE); //使能GPIOA时钟

完整的PWM输出代码示例如下：

#include "stm32f10x.h"

int main(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

    //使能GPIOA时钟
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);

    //使能TIM3时钟
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

    //配置GPIOA6为PWM输出模式
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    //配置TIM3时基
    TIM_TimeBaseStructure.TIM_Period = 999; //PWM周期
    TIM_TimeBaseStructure.TIM_Prescaler = 71; //时钟预分频
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    //配置TIM3通道1为PWM输出模式
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 499; //PWM占空比
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC1Init(TIM3, &TIM_OCInitStructure);

    //使能TIM3
    TIM_Cmd(TIM3, ENABLE);

    while(1)
    {
        //TODO: 业务逻辑
    }
}