![Basic functions of Modem](https://images-na.ssl-images-amazon.com/images/G/01/x-locale/common/grey-pixel.gif)
RS232 or RS485 interface, can’t be used at one time
2G Frequency: GSM850/900,DCS1800/1900, 2G GSM/GPRS
Work Mode: TCP and UDP Client
Supports register packet and heartbeat packet
Can be remote configurated via SMS
Support multi work modes : SMS transmission mode,network transmission mode and httpsD mode
Support basic instruction set and extension instruction set
Hardware flow control RTS/CTS