imux6ull 串口连接移远的4g模块EC200N，使用pppd拨号上网
1 设置内核支持pppd，打开pppd下的所有项，编译内核
Device Drivers —>[] Network device support —>[] PPP(point-to-point protocol) support
2 修改设备树对应的串口和控制端口（使用led模式），注意屏蔽这两个管脚其他功能
led6{label = "gprs_reset";gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;default-state = "off";};led7{label = "gprs_pwrkey";gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;default-state = "off";};
3 安装pppd
sudo apt install ppp
4 安装wvdial
sudo apt install wvdial
5 修改/etc/wvdial.conf，使用的是移动卡
[Dialer Defaults]Init1 = ATZInit2 = ATQ0 V1 E1 S0=0Init3 = AT+CGDCONT=1,"IP","3gnet"Modem Type = Analog ModemBaud = 115200New PPPD = yesModem = /dev/ttymxc1ISDN = 0Phone = *99#Password = cardUsername = cardAuto DNS = on
6 系统启动后，需要拉低power管脚500ms，模块才能开机
echo 1 > /sys/class/leds/gprs_reset/brightnesssleep 1echo 0 > /sys/class/leds/gprs_reset/brightness
7 启动wvdial
wvdial &
--> Initializing modem.--> Sending: ATZATZOK--> Sending: ATQ0 V1 E1 S0=0ATQ0 V1 E1 S0=0OK--> Sending: AT+CGDCONT=1,"IP","3gnet"AT+CGDCONT=1,"IP","3gnet"OK--> Modem initialized.--> Sending: ATDT*99#--> Waiting for carrier.ATDT*99#CONNECT--> Carrier detected. Waiting for prompt.--> Don't know what to do! Starting pppd and hoping for the best.--> Starting pppd at Thu Dec 22 16:58:43 --> Pid of pppd: 7164--> Using interface ppp0--> pppd: ▒▒G[02]▒▒G[02]--> pppd: ▒▒G[02]▒▒G[02]--> pppd: ▒▒G[02]▒▒G[02]--> pppd: ▒▒G[02]▒▒G[02]--> pppd: ▒▒G[02]▒▒G[02]--> local IP address 10.169.89.124--> pppd: ▒▒G[02]▒▒G[02]--> remote IP address 10.64.64.64--> pppd: ▒▒G[02]▒▒G[02]--> primary DNS address 120.196.165.7--> pppd: ▒▒G[02]▒▒G[02]--> secondary DNS address 221.179.38.7--> pppd: ▒▒G[02]▒▒G[02]
8 可以看到生成ppp0节点 ifconfig
ppp0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500inet 10.169.89.124 netmask 255.255.255.255 destination 10.64.64.64ppp txqueuelen 3 (Point-to-Point Protocol)RX packets 5 bytes 62 (62.0 B)RX errors 0 dropped 0 overruns 0 frame 0TX packets 6 bytes 101 (101.0 B)TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
8 关闭其他网络节点，设置默认路由为ppp0
route add default dev ppp0
9 ping 通外网
