1、功能说明

    /* 简单描述工程功能 */
        这个例程配置并演示使用EXIT外部中断及TIM定时器中断


2、使用环境

    软件开发环境：KEIL MDK-ARM V5.34.0.0
                  IAR EWARM 8.50.1
    
    硬件开发环境：    
        N32H473系列：
        基于评估板N32H473VEL7_STB V1.0开发
        N32H474系列：
        基于评估板N32H474VEL7_STB V1.0开发
        N32H475系列：
        基于评估板N32H475UEQ7_STB V1.0开发
        N32H482系列：
        基于评估板N32H482ZEL7_STB V1.0开发
        N32H487系列：
        基于评估板N32H487ZEL7_EVB V1.1开发


3、使用说明

    /* 描述相关模块配置方法；例如:时钟，I/O等 */
    系统时钟配置：
        N32H475/N32H482/N32H487:
            SystemClock：240MHz
        N32H474/N32H473:
            SystemClock：240MHz
            
    打印串口配置：
        N32H474/N32H473/N32H482/N32H487:
            USART：TX - PA9，RX - PA10，波特率115200
        N32H475：
            USART：TX - PA9，RX - PA15，波特率115200
    
    N32H487系列：
        EXIT：PA15为浮空输入模式，外部中断线 - EXIT_LINE15，开启外部中断
    N32H482/N32H475/N32H474/N32H473系列:
        EXIT：PA4为浮空输入模式，外部中断线 - EXIT_LINE4，开启外部中断
    
    TIM：预分频系数 - （SystemClock/50000-1），周期 - （50000-1），开启定时器中断

    /* 描述Demo的测试步骤和现象 */
        1.编译后下载程序复位运行；
        2.查看串口打印信息，定时器中断信息每1S打印一次，按下按键打印停止，再次按下则继续打印，表明程序运行正常；


4、注意事项



1. Function description
    /* A brief description of the engineering function */
    This routine configures and demonstrates the use of EXIT external interrupts and TIM timer interrupts

2. Use environment

    Software development environment: KEIL MDK-ARM V5.34.0.0
                                      IAR EWARM 8.50.1
    Hardware development environment:
        N32H473 series:
        Developed based on the evaluation board N32H473VEL7_STB V1.0
        N32H474 series:
        Developed based on the evaluation board N32H474VEL7_STB V1.0
        N32H475 series:
        Developed based on the evaluation board N32H475UEQ7_STB V1.0
        N32H482 series:
        Developed based on the evaluation board N32H482ZEL7_STB V1.0
        N32H487 series:
        Developed based on the evaluation board N32H487ZEL7_EVB V1.1
        

3. Instructions for use

	/* Describe related module configuration methods; for example: clock, I/O, etc. */
    System Clock Configuration:
        N32H475/N32H482/N32H487:
            SystemClock：240MHz
        N32H474/N32H473:
            SystemClock：240MHz
            
    Print Serial Port Configuration:
        N32H474/N32H473/N32H482/N32H487:
            USART：TX - PA9，RX - PA10, baud rate 115200
        N32H475：
            USART：TX - PA9，RX - PA15, baud rate 115200
    N32H487：               
        EXIT: PA15 is in floating input mode, and external interrupt line -exit_line15 is used to enable external interrupt
    N32H482/N32H475/N32H474/N32H473：               
        EXIT: PA4 is in floating input mode, and external interrupt line -exit_line4 is used to enable external interrupt
        
    TIM: Pre-dividing frequency coefficient - (SystemClock/1200-1), period - (1200-1), start timer interrupt
    /* Describes the test steps and symptoms of Demo */
    1. Reset and run the downloaded program after compilation;
    2. Check the serial port printing information. The timer interrupt information is printed every 1S.
       Press the button to stop printing, and press it again to continue printing, indicating that the program is running normally.

4. Attention
    None
