STM32F103窗口看门狗（WWDG）终极指南：原理、配置与实战

void IWDG_Init(u8 prer,u16 rlr) 
{	
 	IWDG_WriteAccessCmd(IWDG_WriteAccess_Enable);  //使能对寄存器IWDG_PR和IWDG_RLR的写操作
	IWDG_SetPrescaler(prer);  //设置IWDG预分频值:设置IWDG预分频值为64
	IWDG_SetReload(rlr);  //设置IWDG重装载值
	IWDG_ReloadCounter();  //按照IWDG重装载寄存器的值重装载IWDG计数器
	IWDG_Enable();  //使能IWDG
}
//喂独立看门狗
void IWDG_Feed(void)
{   
 	IWDG_ReloadCounter();	//重载计数值									   
}

//保存WWDG计数器的设置值,默认为最大. 
u8 WWDG_CNT=0x7f; 
//初始化窗口看门狗 	
//tr   :T[6:0],计数器值 
//wr   :W[6:0],窗口值 
//fprer:分频系数（WDGTB）,仅最低2位有效 
//Fwwdg=PCLK1/(4096*2^fprer). 

void WWDG_Init(u8 tr,u8 wr,u32 fprer)
{ 
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_WWDG, ENABLE);  //   WWDG时钟使能
	WWDG_CNT=tr&WWDG_CNT;   //初始化WWDG_CNT.
	WWDG_SetPrescaler(fprer);////设置IWDG预分频值
	WWDG_SetWindowValue(wr);//设置窗口值
	WWDG_Enable(WWDG_CNT);	 //使能看门狗 ,	设置 counter .
	WWDG_ClearFlag();//清除提前唤醒中断标志位
	WWDG_NVIC_Init();//初始化窗口看门狗 NVIC
	WWDG_EnableIT(); //开启窗口看门狗中断
} 
//重设置WWDG计数器的值
void WWDG_Set_Counter(u8 cnt)
{
    WWDG_Enable(cnt);//使能看门狗 ,	设置 counter .	 
}
//窗口看门狗中断服务程序
void WWDG_NVIC_Init()
{
	NVIC_InitTypeDef NVIC_InitStructure;
	NVIC_InitStructure.NVIC_IRQChannel = WWDG_IRQn;    //WWDG中断
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;   //抢占2，子优先级3，组2	
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;	 //抢占2，子优先级3，组2	
    NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE; 
	NVIC_Init(&NVIC_InitStructure);//NVIC初始化
}

void WWDG_IRQHandler(void)
{
	WWDG_SetCounter(WWDG_CNT);	  //当禁掉此句后,窗口看门狗将产生复位
	WWDG_ClearFlag();	  //清除提前唤醒中断标志位
	LED1=!LED1;		 //LED状态翻转
}

int main(void)
 {		
	delay_init();	    	 //延时函数初始化	  
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//设置中断优先级分组为组2：2位抢占优先级，2位响应优先级
	uart_init(115200);	 //串口初始化为115200
 	LED_Init();
	KEY_Init();          //按键初始化	 
	LED0=0;
	delay_ms(300);	  
	WWDG_Init(0X7F,0X5F,WWDG_Prescaler_8);//计数器值为7f,窗口寄存器为5f,分频数为8	   
 	while(1)
	{
		LED0=1;			  	   
	}   
}