1 、 Interface feature: compatible interface with EIA/TIA RS-232C,
　　 RS-422/485 standard
2 、 Electric interface: RS-232C interface DB25 hole-type connector,
　　 RS-422/485 interface 4-bit terminal or RJ-11 port
3 、 Transmission media: twisted-pair cable or shielded cable
4 、 Working mode: asynchronous half or full duplex
5 、 Signal indication: a dual color signal indication light indicating TD,
　　 RD data
6 、 Isolation: isolation voltage 3500VRMS 500VDC sequence
7 、 Power supply: serial port electricity stealing at RS-232 end.
　　 External power supply connecting at RS-422/485 end