请用stm32f103c8t6单片机的高级定时器pa0口配置pwm波输出，写出标准库代码并附上注释

好的，下面是标准库代码和注释：

#include "stm32f10x.h"

void TIM3_PWM_Init(u16 arr,u16 psc)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  TIM_OCInitTypeDef TIM_OCInitStructure;

  //使能TIM3和GPIOA时钟
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);   
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);  

  //设置GPIOA口
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;               
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;         
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;        
  GPIO_Init(GPIOA, &GPIO_InitStructure);                  

  //设置TIM3
  TIM_TimeBaseStructure.TIM_Period = arr;                  
  TIM_TimeBaseStructure.TIM_Prescaler = psc;                
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;   
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; 
  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);           

  //设置TIM3通道1
  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_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);          

  //启动TIM3
  TIM_Cmd(TIM3, ENABLE);                                      
}

int main(void)
{
  TIM3_PWM_Init(999, 71);   //初始化PWM波，设置周期为1000，预分频为72
  while (1)
  {
  }
}

注释中会详细介绍每段代码的功能：

#include "stm32f10x.h"   //包含STM32F10x系列单片机的头文件

void TIM3_PWM_Init(u16 arr,u16 psc)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  TIM_OCInitTypeDef TIM_OCInitStructure;

  //使能TIM3和GPIOA时钟
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);   
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);  

  //设置GPIOA口
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;               
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;         
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;        
  GPIO_Init(GPIOA, &GPIO_InitStructure);                  

  //设置TIM3
  TIM_TimeBaseStructure.TIM_Period = arr;                  //设置自动重载值
  TIM_TimeBaseStructure.TIM_Prescaler = psc;                //设置预分频值
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;   //设置时钟分频
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //设置计数模式为向上计数
  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);           //初始化TIM3

  //设置TIM3通道1
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;         //设置PWM模式1
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //使能TIM3的输出通道1
  TIM_OCInitStructure.TIM_Pulse = 0;                         //设置占空比为0
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;  //设置输出极性为高电平
  TIM_OC1Init(TIM3, &TIM_OCInitStructure);                  

  TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);          //使能TIM3的输出通道1的预装载功能

  //启动TIM3
  TIM_Cmd(TIM3, ENABLE);                                     //使能TIM3
}

int main(void)
{
  TIM3_PWM_Init(999, 71);   //初始化PWM波，设置周期为1000，预分频为72
  while (1)
  {
  }
}

以上是使用STM32F103C8T6单片机的高级定时器PA0口配置PWM波输出的标准库代码和注释。