stm8串口与上位机进行通信，上位机先发送数据给单片机，单片机再将数据反馈给上位机(Stm8 serial communication with the host computer through the computer, sends the data to the MCU, MCU and data feedback to the host computer)

STM8 常用底层驱动，很好用，齐全(STM8 is often used to drive the bottom, very well used, complete)