1、功能说明
    1、通过EXTI线来触发时间戳。

2、使用环境

    软件开发环境：KEIL MDK-ARM V5.34
                  IAR EWARM 8.50.1
				  
    硬件开发环境：
        基于全功能板N32H497ZGL7_EVB V1.0开发

3、使用说明
    
    系统配置:
        1、时钟源：LSE
        2、EXTI中断IO：PB8
        3、串口配置：
                    - 串口为USART1（TX：PA9  RX：PA10）:
                    - 数据位：8
                    - 停止位：1
                    - 奇偶校验：无
                    - 波特率： 115200 
    使用方法：
        编译后烧录到评估板，把PC13连接到PB8，上电后，串口每隔1S会打印时间戳输出。

4、注意事项
    无


1. Function description

    1. The timestamp is triggered by the EXTI line.

2. Use environment

    Software development environment: KEIL MDK-ARM V5.34
                                      IAR EWARM 8.50.1
									  
    Hardware development environment:
        Developed based on the full-function board N32H497ZGL7_EVB V1.0

3. Instructions for use

    System configuration:

        1. Clock source: LSE
        2. EXTI interrupt IO: PB8
        3. Serial port configuration:

                            - Serial port: USART1 (TX: PA9 RX: PA10) :
                            - Data bit: 8
                            - Stop bit: 1
                            - Parity check: None
                            - Baud rate: 115200

    Instructions:
        After compiling, it is burned to the evaluation board. After connecting PC13 to PB8, the serial port will print timestamp output every 1S after power-on.

4. Attention
    None
