STM32 | 精确控制PWM脉冲个数

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精确控制PWM个数采用的是主从方案， TIM3产生PWM,为TIM2提供时钟，然后TIM2计数

测试代码如下（待完善），仅供参考

主要的文件就是time.c文件

main.c文件

#include "stm32f10x.h"#include "time.h"#include "usart.h"
void Delay(unsigned int Time){  if(Time == 0) return;  while(Time--);}
int main(){      //NVIC_  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);    TIM2_init(7199,999);/// 1/10=0.01  TIM3_init(7199,99);/// 1/100=0.1  //99    usart1_init(115200);  //SetPWMValue(TIM2,1,500);    SetPWMValue(TIM3,1,50);  UartPutChar(USART1,0X56); while(1) {     // UartPutChar(USART1,0X56);   Delay(100);  if(flag==1)  {      TIM3_init(7199,(100+time_count*100)-1);       SetPWMValue(TIM3,1,50);      if(time_count==10)    {      time_count=0;      TIM_Cmd(TIM3,DISABLE);    }
    flag=0;  }       ; }
}

time.c文件

#include "stm32f10x.h"#include "time.h"

/************************T2的定时器初始化*************************/void TIM2_init(unsigned int pres,unsigned int period) {  TIM_TimeBaseInitTypeDef TIM_TimeBaseInitTypeStruct;  NVIC_InitTypeDef NVIC_InitTypeStruct;  TIM_OCInitTypeDef   TIM_OCInitTypeStruct;  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);    //TIM_TimeBaseInitTypeStruct.TIM_Prescaler=pres;  TIM_TimeBaseInitTypeStruct.TIM_CounterMode=TIM_CounterMode_Up;  //TIM_TimeBaseInitTypeStruct.TIM_Period=period;  TIM_TimeBaseInitTypeStruct.TIM_ClockDivision=TIM_CKD_DIV1;  TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitTypeStruct);    TIM_ITConfig(TIM2,TIM_IT_Trigger,ENABLE);      NVIC_InitTypeStruct.NVIC_IRQChannel=TIM2_IRQn;  NVIC_InitTypeStruct.NVIC_IRQChannelPreemptionPriority=2;  NVIC_InitTypeStruct.NVIC_IRQChannelSubPriority=2;  NVIC_InitTypeStruct.NVIC_IRQChannelCmd=ENABLE;  NVIC_Init(&NVIC_InitTypeStruct);      TIM_SelectInputTrigger(TIM2,TIM_TS_ITR2);  TIM_SelectSlaveMode(TIM2, TIM_SlaveMode_External1);  TIM_SelectMasterSlaveMode(TIM2,TIM_MasterSlaveMode_Enable);      TIM_Cmd(TIM2,ENABLE);  }

/************************T3输出PWM控制T2的计数*************************/
void TIM3_init(unsigned int pres,unsigned int period) {  GPIO_InitTypeDef  GPIO_InitTypeStruct;  TIM_TimeBaseInitTypeDef TIM_TimeBaseInitTypeStruct;  TIM_OCInitTypeDef   TIM_OCInitTypeStruct;  NVIC_InitTypeDef NVIC_InitTypeStruct;    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO,ENABLE);    GPIO_InitTypeStruct.GPIO_Pin=GPIO_Pin_6|GPIO_Pin_7;  GPIO_InitTypeStruct.GPIO_Mode=GPIO_Mode_AF_PP;  GPIO_InitTypeStruct.GPIO_Speed=GPIO_Speed_50MHz;  GPIO_Init(GPIOA,&GPIO_InitTypeStruct);    TIM_TimeBaseInitTypeStruct.TIM_Prescaler=pres;  TIM_TimeBaseInitTypeStruct.TIM_CounterMode=TIM_CounterMode_Up;  TIM_TimeBaseInitTypeStruct.TIM_Period=period;  TIM_TimeBaseInitTypeStruct.TIM_ClockDivision=TIM_CKD_DIV1;  TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitTypeStruct);  //  TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE);    TIM_OCInitTypeStruct.TIM_OCMode=TIM_OCMode_PWM1;  TIM_OCInitTypeStruct.TIM_OutputState=TIM_OutputState_Enable;  TIM_OCInitTypeStruct.TIM_Pulse=0;  TIM_OCInitTypeStruct.TIM_OCPolarity=TIM_OCPolarity_High;  TIM_OCInitTypeStruct.TIM_OCIdleState=TIM_OCIdleState_Set;    TIM_OC1Init(TIM3,&TIM_OCInitTypeStruct);  
//        //Master  TIM_CtrlPWMOutputs(TIM3,ENABLE);   TIM_Cmd(TIM3,ENABLE);

  TIM_SelectOutputTrigger(TIM3,TIM_TRGOSource_OC1Ref );   TIM_SelectMasterSlaveMode(TIM3,TIM_MasterSlaveMode_Enable);    }unsigned char time_count0=0;unsigned char time_count=0;unsigned char flag=0;void TIM2_IRQHandler(){  TIM_TimeBaseInitTypeDef TIM_TimeBaseInitTypeStruct;  if(TIM_GetITStatus(TIM2,TIM_IT_Trigger)!=RESET)  {            /*        T2 TIM_SlaveMode_Gated    time_count0++;放在本函数前面    //TIM2_init(7199,99);/// 1/10=0.01    //TIM3_init(7199,99);/// 1/100=0.01    count 1 /pwm 0 个脉冲    count 2 /pwm 2 个脉冲    count 3 /pwm 4 个脉冲    count 4 /pwm 6 个脉冲        //TIM2_init(7199,999);/// 1/10=0.1    //TIM3_init(7199,99);/// 1/100=0.01    count 1 /pwm 0 个脉冲    count 2 /pwm 20 个脉冲    count 3 /pwm 40 个脉冲    count 4 /pwm ？个脉冲        //TIM2_init(7199,99);/// 1/10=0.1    //TIM3_init(7199,999);/// 1/100=0.01    count 1 /pwm 0 个脉冲    count 2 /pwm 2 个脉冲    count 3 /pwm 4 个脉冲    count 4 /pwm 6 个脉冲        */   /*  T2 TIM_SlaveMode_Trigger模式      T3每产生一次PWM脉冲将会使T2计数一次               */        if(time_count0==11) //    {      time_count++;      SetPWMValue(TIM3,1,0);      flag=1;      UartPutChar(USART1,time_count0);//     //       time_count0=0;            //TIM_Cmd(TIM2,DISABLE);    }    time_count0++;    
              /*         T2 TIM_SlaveMode_Gated        time_count0++;放在本函数后面    //TIM2_init(7199,99);/// 1/10=0.01    //TIM3_init(7199,99);/// 1/100=0.01    count 1 /pwm 2 个脉冲    count 2 /pwm 4 个脉冲    count 3 /pwm 6 个脉冲    count 4 /pwm 8 个脉冲        //TIM2_init(7199,999);/// 1/10=0.1    //TIM3_init(7199,99);/// 1/100=0.01    count 1 /pwm 20 个脉冲    count 2 /pwm 40 个脉冲    count 3 /pwm 60 个脉冲    count 4 /pwm ？个脉冲        //TIM2_init(7199,99);/// 1/10=0.1    //TIM3_init(7199,999);/// 1/100=0.01    count 1 /pwm 2 个脉冲    count 2 /pwm 4 个脉冲    count 3 /pwm 6 个脉冲    count 4 /pwm 8 个脉冲        */    TIM_ClearITPendingBit(TIM2,TIM_IT_Trigger);  }    }

void SetPWMValue(TIM_TypeDef* TIMx,unsigned char  channel,unsigned int data){  if(channel==1)  {   TIM_SetCompare1(TIMx,data);  }  else if(channel==2)  {   TIM_SetCompare2(TIMx,data);  }  else if(channel==3)  {   TIM_SetCompare3(TIMx,data);  }  else if(channel==4)  {   TIM_SetCompare4(TIMx,data);  }}

以上为相关程序代码，其他的.h文件可自行添加 很简单

  

       

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