Main features：
>Support mobile EC20 / ec200t-lte module 2g 3g 4G dial-up Internet access；
>Support dual network port 1wan + 1lan or 2lan mode, can be selected through the page, support WAN port connection to the external network;
>Support WiFi sta mode, can choose to use STA to connect the superior route to connect to the external network;
>The system supports serial data transparent transmission mode by default, and supports server type TCP / mqtt board side as client side;
>Support RS232 / RS485 working mode, optional;
>Support RS485 working mode to select transmission direction automatically;
>It supports wide power input dc9-36v, and ultra-low energy consumption is only 2W;
>Board level built-in multi-level anti surge protection circuit, isolation circuit;
>Industrial grade stable SIM card holder;
>The system supports RS232 / RS485 data transparent transmission mode by default, and supports server type TCP / mqtt, and the board side is client side;
>It can provide IO pin using block diagram, users can program and write RS232 / RS485 data, and develop transmission protocol or firmware by themselves;
