介绍了Linux下的串口驱动的设计层次及接口, 并指出串口与TTY终端之间的关联层次(串口可作TTY终端使用), 以及Linux下的中断处理机制/中断共享机制, 还有串口缓冲机制当中涉及的软中断机制 -Linux serial driver level design and interface, and pointed out that the level of association between the serial TTY terminal (serial port can be used for TTY terminal), and interrupt handling mechanism under Linux/interrupt sharing mechanism, as well as the serial buffer mechanism involving soft interrupt mechanism