1、 sketch

TX2 There is no default EC20（4G modular ） The driver .

Connect usb after , Use lsusb Check to see EC20 Of vid and pid, But you can't surf the Internet , So it needs to be transplanted EC20 The driver

Bus 001 Devide 004: ID 2c7c:0125

2、4G Drive Brief

In the moving away manual 《Quectel_WCDMA&LTE_Linux_USB_Driver_User_Guide_V1.8.pdf》 in , There are drive types supported by various models of modules .
among EC20 Three types of drivers are supported , Namely ：USB Serial、GobiNet、QMI WWAN

2.1 USB Serial

Drive will usb Convert to serial port , stay /dev Hypogenesis ttyUSB0、ttyUSB1、ttyUSB2…… Equal serial port , These serial ports can be used AT Orders and PPP Dial-up Internet access ;
PPP（ Point to point agreement ） Used in dialing MS and PC Data interaction between the two 、 negotiation . At the beginning of the dialing process, the first thing to start is PC and MS direct PPP The process , After successful dialing , Still need to rely on PPP Protocol pair IP Packets are encapsulated to transmit data .

2.2 GobiNet

GobiNet：GOBI qualcomm Gobi No linewidth