arcNET网络协议转串口的程序。基于C8051F040.20 mA电流环通讯-arcNET network protocol to serial program. Based on C8051F040.20 mA current ring communication

COM20020D是ARCNET控制芯片，本程序示范了其使用方法-COM20020D is ARCNET controller chip, this program demonstrates the use of methods