这是一个集串口通讯、数据库管理、文件管理和打印机管理于一体的VC程序，很值得初学VC者好好借鉴。-This is a collection serial communications, database management, document management and printer management integrates the VC Program, is worth learning from VC properly.

CH341是一个USB总线的转接芯片，通过USB总线提供串口、打印口或者并口。 在串口方式下，CH341提供串口发送使能、串口接收就绪等交互式的速率控制信号以 及常用的MODEM联络信号，用于将普通的串口设备直接升级到USB总线。 -CH341 is a USB bus adapter chips, provided through the USB serial bus, printer port or parallel port. In serial mode, CH341 Send