1、功能说明
    1、此例程展示了CM4内核下的WWDG复位功能。

2、使用环境

    软件开发环境：KEIL MDK-ARM V5.34
    		  IAR EWARM 8.50.1

    芯片支持：
        N32H785
        N32H785EC
        N32H787  	  

3、使用说明

    系统配置
        1、时钟源：HSI+PLL
        2、系统时钟频率：   
		    M7核 600MHz  M4核 300MHz
      3、指示灯：PA1(LED1)  PA3(LED3)  
             
    测试步骤与现象：

        1、编译后将CM7和CM4的工程程序分别下载到开发板并复位运行。
		2、上电后，指示灯LED3不停的闪烁。说明窗口值刷新正常，代码正常运行。
        3、当把systick_delay_ms()函数参数改成小于或者大于窗口值时，整个系统将一直处于复位状态。LED1亮。

4、注意事项
    1、当窗口值很小时，系统处于频繁的复位状态，此时，容易引起程序无法正常下载。本例程中在开启WWDG前加了1秒延时来避免这个现象。当然也可以不用延时，直接将BOOT0引脚拉高即可正常下载。 

1. Function description

   This example shows  WWDG reset function in the condition of CM4.
    
2. Development environment

    Software development environment: KEIL MDK-ARM V5.34
    		                      IAR EWARM 8.50.1
    
    Supported chips:
        N32H785
        N32H785EC
        N32H787       

3. How to use

    System Configuration:
        1. Clock source: HSI+PLL
        2. System Clock frequency: 
            M7 Core：600MHz  M4 Core：300MHz
     3、PA1(LED1)  PA3(LED3)  

    Test steps and phenomenon：
	   1. After compiling, download the program of CM7 and CM4 projects respectively and reset, the program start running；
       2. The indicator LED3 keeps flashing，It means that the window value is refreshed normally and the code is running normally.
       3. When the parameter of the systick_delay_ms() function is changed less than or greater than window value,  the entire system will always be in the reset state. LED1 is on.

4. Attention
    1. When the window value is very small, the system is in a frequent reset state, and at this time, it is easy to 
       cause the program to fail to download normally. In this routine, 1s delay is added before WWDG is 
       turned on to avoid this phenomenon. Of course, without delay, you can directly pull up the BOOT0 pin to download normally.