原来例程PA8很亮，加了tim2的ch1后，PA8虽然也是幽暗变亮，但亮度小多了，求解

sunsungang

原来例程PA8很亮，加了tim2的ch1后，PA8虽然也是幽暗变亮，但亮度小多了，求解

#include "pwm.h"
#include "led.h"
//////////////////////////////////////////////////////////////////////////////////	 
//±????ò???©?§?°??????????×÷???í???????????????ü????????
//ALIENTEK Mini STM32??·?°?
//PWM  ?????ú??			   
//??????×?@ALIENTEK
//????????:www.openedv.com
//????????:2010/12/03
//°?±???V1.0
//°??¨?ù??????°?±?????
//Copyright(C) ??????×? 2009-2019
//All rights reserved
////////////////////////////////////////////////////////////////////////////////// 	  


//PWM??????????
//arr??×?????×°??
//psc???±???¤·?????



void TIM1_PWM_Init(u16 arr,u16 psc)
{  
	 GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;

	RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);// 
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);  //????GPIO???è?±??????
	                                                                     	

   //?è??????????????????????,????TIM1 CH1??PWM?????¨??
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8; //TIM_CH1
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //???????ì????
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	
	TIM_TimeBaseStructure.TIM_Period = arr; //?è???????????ü??????×°????????×?????×°???????÷????????	 80K
	TIM_TimeBaseStructure.TIM_Prescaler =psc; //?è??????×÷??TIMx?±?????????????¤·?????  ??·???
	TIM_TimeBaseStructure.TIM_ClockDivision = 0; //?è???±??·???:TDTS = Tck_tim
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM?ò??????????
	TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //?ù??TIM_TimeBaseInitStruct?????¨????????????TIMx???±???ù??????

 
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //?????¨?±?÷????:TIM?????í???÷??????2
	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //±???????????
	TIM_OCInitStructure.TIM_Pulse = 0; //?è????×°??????±????????÷????????
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //????????:TIM????±?????????
	TIM_OC1Init(TIM1, &TIM_OCInitStructure);  //?ù??TIM_OCInitStruct?????¨???????????????èTIMx

  TIM_CtrlPWMOutputs(TIM1,ENABLE);	//MOE ?÷????????	

	TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);  //CH1?¤×°??????	 
	
	TIM_ARRPreloadConfig(TIM1, ENABLE); //????TIMx??ARR?????¤×°???????÷
	
	TIM_Cmd(TIM1, ENABLE);  //????TIM1
 
   
}

void TIM2_IRQHandler(void)   //TIM3????
{
	if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) //?ì?é???¨??TIM????·??ú??·?:TIM ?????? 
		{
		TIM_ClearITPendingBit(TIM2, TIM_IT_Update  );  //????TIMx???????????í??:TIM ?????? 
		LED1=!LED1;
		}
}
void TIM2_PWM_Init(u16 arr,u16 psc)
{  
	 GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;

	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);// 
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);  //????GPIO???è?±??????
	                                                                     	

   //?è??????????????????????,????TIM1 CH1??PWM?????¨??
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //TIM_CH1
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //???????ì????
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	
	TIM_TimeBaseStructure.TIM_Period = arr; //?è???????????ü??????×°????????×?????×°???????÷????????	 80K
	TIM_TimeBaseStructure.TIM_Prescaler =psc; //?è??????×÷??TIMx?±?????????????¤·?????  ??·???
	TIM_TimeBaseStructure.TIM_ClockDivision = 0; //?è???±??·???:TDTS = Tck_tim
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM?ò??????????
	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); //?ù??TIM_TimeBaseInitStruct?????¨????????????TIMx???±???ù??????

 
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //?????¨?±?÷????:TIM?????í???÷??????2
	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //±???????????
	TIM_OCInitStructure.TIM_Pulse = 0; //?è????×°??????±????????÷????????
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //????????:TIM????±?????????
	TIM_OC1Init(TIM2, &TIM_OCInitStructure);  //?ù??TIM_OCInitStruct?????¨???????????????èTIMx

  TIM_CtrlPWMOutputs(TIM2,ENABLE);	//MOE ?÷????????	

	TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);  //CH1?¤×°??????	 
	
	TIM_ARRPreloadConfig(TIM2, ENABLE); //????TIMx??ARR?????¤×°???????÷
	
	TIM_Cmd(TIM2, ENABLE);  //????TIM1
 
   
}
int main(void)
 {	
	u16 led0pwmval=0;    
	u8 dir=1;	
	delay_init();	    	 //???±??????????	  
	LED_Init();		  	//????????LED??????????????
	TIM1_PWM_Init(899,0);//??·?????PWM????=72000/(899+1)=80Khz
	TIM2_PWM_Init(899,0);
   	while(1)
	{
 		delay_ms(10);	 
		if(dir)led0pwmval++;
		else led0pwmval--;	 
 		if(led0pwmval>800)dir=0;
		if(led0pwmval==0)dir=1;	   					 
		TIM_SetCompare1(TIM1,led0pwmval);	
		TIM_SetCompare1(TIM2,led0pwmval);
	} 
}[/mw_shl_code]

正点原子

说明你占空比太小了