前言

对于4G模块上网拨号上网有很多方法，本文针对PPP的拨号说明，至于USB串口驱动配置，请查看前面的文章：4G模块驱动移值。

一、PPP的下载和交叉编译

ppp库文件可以去http://ppp.samba.org/下载最新版本

1、解包

# tar zxvf  ppp-2.4.7.tar.gz

2、配置

# cd ppp-2.4.7

# ./configure

3、编译

# make CC=arm-hismall-linux-gcc

注意：arm-hismall-linux-gcc为交叉编译器

二、ppp的内核配置和ppp拨号

1、配置内核支持ppp

# make ARCH=arm CROSS_COMPILE=arm-hismall-linux- menuconfig

[*] Device Drivers →

[*] Network device support →

[*] PPP (point-to-point protocol) support

2、编译内核

# make ARCH=arm CROSS_COMPILE=arm-hismall-linux- uImage

3、ppp拨号

把编译出的pppd/pppd和chat/chat拷贝到linux板中的/usr/sbin/下

通过几个不同的配置文件，在拨号的时候选择相应的配置文件，现将配置文件列举如下：

FILE：/etc/ppp/peers/bc82-pppd

#Modem path, like /dev/ttyUSB3,/dev/ttyACM0, depend on your module, default path is /dev/ttyUSB3

/dev/ttyUSB1 115200

#Insert the username and password for authentication, default user and password are test

user "" password ""

# The chat script, customize your APN in this file

connect '/usr/sbin/chat -s -v -f /etc/ppp/peers/bc82-chat-connect'

# The close script

disconnect '/usr/sbin/chat -s -v -f /etc/ppp/peers/bc82-chat-disconnect'

# Hide password in debug messages

hide-password

# The phone is not required to authenticate

noauth

# Debug info from pppd

debug

# If you want to use the HSDPA link as your gateway

defaultroute

# pppd must not propose any IP address to the peer

noipdefault

# No ppp compression

novj

novjccomp

noccp

ipcp-accept-local

ipcp-accept-remote

local

# For sanity, keep a lock on the serial line

lock

modem

dump

nodetach

# Hardware flow control

nocrtscts

remotename 3gppp

ipparam 3gppp

ipcp-max-failure 10

# Ask the peer for up to 2 DNS server addresses

usepeerdns

FILE：/etc/ppp/peers/bc82-chat-connect

ABORT "BUSY"

ABORT "NO CARRIER"

ABORT "ERROR"

#ABORT "NO ANSWER"

TIMEOUT 10

"" AT

"OK-+++\c-OK" ATH0

OK ATE0

OK ATI;+CESQ;+CPIN?;+COPS?;+CEREG?;+CGREG?;&D2

#china unicom's apn is 3gnet

#OK AT+CGDCONT=1,"IP","3gnet",,0,0

#OK ATD*99#

#China mobile APN

OK AT+CGDCONT=1,"IP","cmnet"

#OK ATDT*99***1#

OK ATD*99#

CONNECT ""

FILE：/etc/ppp/peers/bc82-chat-disconnect

TIMEOUT 5

ABORT "ERROR"

ABORT "NO DIALTONE"

ABORT "NO CARRIER"

#SAY "\nSending break to the modem\n"

"" "+++\c"

OK "ATH0"

SAY "\nGoodbay\n"

编辑好这几个文件之后，便可以通过pppd进行拨号：

#  pppd call  bc82-pppd &

如果拨号成功会有以下信息打印出来：

此时通过ifconfig命令查看网卡就有一个ppp0网卡出现，就可以用模块连接到互联网了