这部分代码是使用函数的重定向使printf函数输出到usart1-This part of the code is the printf function using the function redirect output to usart1

基于stm32zet6的printf重定向，能在串口上用printf语句显示需要显示的内容(Printf redirection based on stm32zet6 can display the content that needs to be displayed with printf statement on the serial port.)