1，使用pppd2.4.5版本，静态交叉编译pppd和chat后，将pppd，chat传到开发板中；
执行pppd命令如下：
代码： 全选
#pppd connect 'chat -v "" "AT" "" "ATDT*99# CONNECT"' user CARD password CARD /dev/ttyUSB0 115200 nodetach crtscts debug usepeerdns defaultroute
Warning: couldn't open ppp database /var/run/pppd2.tdb
[color=#BF0000]bbbbbbbbbbbbbbbbbbbbbbbbbb[/color]这里是我在源代码pppd/auth.C中添加的打印信息。
Fatal signal 11
Script chat -v "" "AT" "" "ATDT*99# CONNECT" finished (pid 1633), status = 0x7f
Connect script failed
Show the Channel's connect value: -1 //在调用chat时，不能分配到channel！
#代码： 全选
#sudo ./pppd connect '/home/user/mydisk/ww/chat -v "" "AT" "" "ATDT*99# CONNECT"' user CARD password CARD /dev/ttyUSB_utps_modem 115200 nodetach crtscts debug usepeer
[sudo] password for user:
Script /home/user/mydisk/ww/chat -v "" "AT" "" "ATDT*99# CONNECT" finished (pid 2236), status = 0x0
Serial connection established.
Show the Channel's connect value: 7 可以分配到channel，并且成功连接
qqqqqqqqqwwwwwwwwwwwwwwweeeeeeeeeeeeeee
using channel 1
Using interface ppp0
Connect: ppp0 <--> /dev/ttyUSB_utps_modem
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x559ef22b> <pcomp> <accomp>]
rcvd [LCP ConfReq id=0x0 <asyncmap 0x0> <auth chap MD5> <magic 0xf7f856> <pcomp> <accomp>]
sent [LCP ConfAck id=0x0 <asyncmap 0x0> <auth chap MD5> <magic 0xf7f856> <pcomp> <accomp>]
rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x559ef22b> <pcomp> <accomp>]
sent [LCP EchoReq id=0x0 magic=0x559ef22b]
rcvd [LCP DiscReq id=0x1 magic=0xf7f856]
……在开发板上使用AT命令测试转换后的3G模块：
代码： 全选
# echo ATDT*99#>/dev/ttyUSB0
# cat /dev/ttyUSB0 ATDT*99#
CONNECT 7200000
NO CARRIER