我用的tim2输出pwm为什么没有波形啊

梦行0807

#include "pwm_output.h"

/*
 * 函数名：TIM2_GPIO_Config
 * 描述  ：配置TIM2复用输出PWM时用到的I/O
 * 输入  ：无
 * 输出  ：无
 * 调用  ：内部调用
 */
static void TIM2_GPIO_Config(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

 //PCLK1经过2倍频后作为TIM2的时钟源等于36MHz
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);

  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_0 | GPIO_Pin_1| GPIO_Pin_2| GPIO_Pin_3;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;      // 复用推挽输出
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_Init(GPIOA, &GPIO_InitStructure);

 
}

static void TIM2_Mode_Config(void)
{
 TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
 TIM_OCInitTypeDef  TIM_OCInitStructure;

 /* PWM信号电平跳变值 */
 u16 CCR1_Val = 500;       
 u16 CCR2_Val = 375;
 u16 CCR3_Val = 250;
 u16 CCR4_Val = 125;

 

  /* Time base configuration */  
  TIM_TimeBaseStructure.TIM_Period = 999;       //当定时器从0计数到999，即为1000次，为一个定时周期
  TIM_TimeBaseStructure.TIM_Prescaler = 0;     //设置预分频：不预分频，即为36MHz
  TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分频系数：不分频
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //向上计数模式

  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

  /* PWM1 Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;     //配置为PWM模式1
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; 
  TIM_OCInitStructure.TIM_Pulse = CCR1_Val;    //设置跳变值，当计数器计数到这个值时，电平发生跳变
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;  //当定时器计数值小于CCR1_Val时为高电平

  TIM_OC1Init(TIM2, &TIM_OCInitStructure);  //使能通道1

  TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);

  /* PWM1 Mode configuration: Channel2 */
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR2_Val;   //设置通道2的电平跳变值，输出另外一个占空比的PWM

  TIM_OC2Init(TIM2, &TIM_OCInitStructure);   //使能通道2

  TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable);

  /* PWM1 Mode configuration: Channel3 */
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR3_Val; //设置通道3的电平跳变值，输出另外一个占空比的PWM

  TIM_OC3Init(TIM2, &TIM_OCInitStructure);  //使能通道3

  TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable);

  /* PWM1 Mode configuration: Channel4 */
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR4_Val; //设置通道4的电平跳变值，输出另外一个占空比的PWM

  TIM_OC4Init(TIM2, &TIM_OCInitStructure); //使能通道4

  TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable);

  TIM_ARRPreloadConfig(TIM2, ENABLE);    // 使能TIM3重载寄存器ARR

  /* TIM3 enable counter */
  TIM_Cmd(TIM2, ENABLE);                   //使能定时器3 
}

void TIM2_PWM_Init(void)
{
 TIM2_GPIO_Config();
 TIM2_Mode_Config(); 
}

正点原子

...

The_Common_God

楼主   解决了吗  我也是跟楼主一样配置的TIM2   但是没有波形输出    这是为什么呀   但是我配置的TIM3可以正常输出波形

Dragontotem

回复【3楼】The_Common_God:
---------------------------------
void Timer2_Init(void)
{
RCC->APB1ENR|=1<<0;  //TIM2时钟使能
    RCC->APB2ENR|=1<<2;     //使能PORTA时钟     

 GPIOA->CRL&=0XFFFF0000; //PA0--CH1 A2--CH2 A2--CH3 A3--CH4
 GPIOA->CRL|=0X0000bbbb; //复用功能输出 
 TIM2->ARR=2000;   //设定计数器自动重装值 
 TIM2->SC=4000;   //预分频器


 TIM2->CCMR1|=7<<4;   //CH1 WM2模式   
 TIM2->CCMR1|=1<<3;      //CH1预装载使能    
 TIM2->CCER|=1<<0;    //OC1 输出使能
     
 
 TIM2->CCMR1|=7<<12;   //CH2 WM2模式   
 TIM2->CCMR1|=1<<11;  //CH2预装载使能    
 TIM2->CCER|=1<<4;    //OC2 输出使能
  

 TIM2->CCMR2|=7<<4;   //CH3 WM2模式   
 TIM2->CCMR2|=1<<3;      //CH3预装载使能    
 TIM2->CCER|=1<<8;    //OC3 输出使能
    
  
 TIM2->CCMR2|=7<<12;   //CH4 WM2模式   
 TIM2->CCMR2|=1<<11;  //CH4预装载使能    
 TIM2->CCER|=1<<12;    //OC4 输出使能

 TIM2->CCR1=1000;           
 TIM2->CCR2=1000;       
 TIM2->CCR3=1000;       
 TIM2->CCR4=1000;        
      
 TIM2->CR1|=1<<7;        //ARPE使能 
 TIM2->CR1|=0x01;     //使能定时器3 
 }