定時器分為普通定時器和高級定時器。STM32和GD32都有TIMERX_CHX_ON或者TIMERX_CHXN,這種定時器是一種互補(bǔ)定時器，我們同樣可以看到還存在與其名字很像的TIMERX_CHX，TIMERX_CHX，這些都是基本的定時器，按照基本的配置即可產(chǎn)生PWM信號，這里不做介紹 。

下面主要說一下利用互補(bǔ)通道產(chǎn)生PWM信號。

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

	RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);	//使能定時器3時鐘
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB  | RCC_APB2Periph_AFIO, ENABLE);  //使能GPIO外設(shè)和AFIO復(fù)用功能模塊時鐘
	TIM_DeInit(TIM1);
	TIM_InternalClockConfig(TIM1);
//	GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3, ENABLE); //Timer3部分重映射  TIM3_CH2->PB5    
 
   //設(shè)置該引腳為復(fù)用輸出功能,輸出TIM1 的PWM脈沖波形	GPIOB.13
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13; //TIM_CH2
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //復(fù)用推挽輸出
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIO
 
   //初始化TIM3
	TIM_TimeBaseStructure.TIM_Period = arr; //設(shè)置在下一個更新事件裝入活動的自動重裝載寄存器周期的值
	TIM_TimeBaseStructure.TIM_Prescaler =psc; //設(shè)置用來作為TIMx時鐘頻率除數(shù)的預(yù)分頻值 
	TIM_TimeBaseStructure.TIM_ClockDivision = 0; //設(shè)置時鐘分割:TDTS = Tck_tim
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上計數(shù)模式
	TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //根據(jù)TIM_TimeBaseInitStruct中指定的參數(shù)初始化TIMx的時間基數(shù)單位
	
	//初始化TIM1 Channel2 PWM模式	 
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1 ; //選擇定時器模式:TIM脈沖寬度調(diào)制模式2
//	TIM_OCInitStructure.TIM_Pulse = 0;
 	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //輸出使能
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //輸出極性:TIM輸出比較極性高
	TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;  //互補(bǔ)輸出極性
	TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable; //互補(bǔ)輸出使能
	TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;  //死區(qū)后輸出狀態(tài)
	TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Set;  //死區(qū)后互補(bǔ)輸出狀態(tài)
	
	TIM_OC1Init(TIM1, &TIM_OCInitStructure);  //根據(jù)T指定的參數(shù)初始化外設(shè)TIM1 OC2
	TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的預(yù)裝載寄存器
  TIM_OC2Init(TIM1, &TIM_OCInitStructure);  //根據(jù)T指定的參數(shù)初始化外設(shè)TIM1 OC2
	TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的預(yù)裝載寄存器
	TIM_OC3Init(TIM1, &TIM_OCInitStructure);  //根據(jù)T指定的參數(shù)初始化外設(shè)TIM1 OC2
	TIM_OC3PreloadConfig(TIM1, TIM_OCPreload_Enable);  //使能TIM1在CCR2上的預(yù)裝載寄存器

	
	TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable; //自動輸出使能
  TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable; //剎車功能使能
	TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_Break_Disable; //剎車輸入極性
	TIM_BDTRInitStructure.TIM_DeadTime = 36; //死區(qū)時間設(shè)置
	TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF; //鎖定設(shè)置
	TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable; //空閑模式下輸出選擇
	TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable; //運行模式下按輸出選擇
  
	TIM_CtrlPWMOutputs(TIM1,ENABLE);   //輸出使能必須要有
	TIM_Cmd(TIM1, ENABLE);  //使能TIM3
}

接下來就是調(diào)用硬件驅(qū)動接口即可完成對PWM信號的產(chǎn)生與驅(qū)動。

如下：

int main(void)
 {		
 	u16 led0pwmval=0;
	u8 dir=1;	
	delay_init();	    	 //延時函數(shù)初始化	  


 	TIM1_PWM_Init(899,0);	 //不分頻。PWM頻率=72000000/900=80Khz
   	while(1)
	{
 		delay_ms(10);	 
		if(dir)led0pwmval++;
		else led0pwmval--;

 		if(led0pwmval>300)dir=0;
		if(led0pwmval==0)dir=1;										 
		TIM_SetCompare1(TIM1,led0pwmval);		   
	}	 
 }

l利用keil測試debug。

審核編輯：湯梓紅