I have a 3G dongle (ITON EW4.2) used on an embedded linux system.When I plug it in to the USB interface and dial for the first time,it
use the /dev/ttyUSB0 to communicate AT command and works well.Then I hang it up, and dial again, this time the device change to /dev/ttyUSB2 to communicate AT command ,so I have to modify my AT char script ,use ttyUSB2 ,even though, it doesn't work well, fail to dial.When I re-plug the device ,it dials succeed again.
Below is what the terminal print. Is there anybody come across the problem the same as me ?What is the reason and how to resolve??
my ppp option file
Code: Select all
"hide-password
persist
nodetach
holdoff 0
connect-delay 100
noauth
/dev/ttyUSB0
115200
debug
defaultroute
ipcp-accept-local
ipcp-accept-remote
usepeerdns
crtscts
lock
noccp
noipdefault
active-filter outbound
demand
idle 300
user ctnet@mycdma.cn
password vnet.mobi
mtu 1490
mru 1490
connect '/bin/chat -v -t10 -f /var/usb3g.chat'"
Code: Select all
ECHO ON
ABORT 'NO DIAL TONE'
ABORT 'NO ANSWER'
ABORT 'NO CARRIER'
ABORT 'DELAYED'
ABORT 'COMMAND NOT SUPPORT'
'' 'AT'
'OK' 'ATZ'
'OK' "ATQ0 V1 E1 S0=0 &C0 &D2"
#'OK' 'AT+CGDCONT=1,"IP","#777"'
#
SAY 'dial...'
'OK' 'ATD#777'
'CONNECT' ''
Code: Select all
"hide-password
persist
nodetach
holdoff 0
connect-delay 100
noauth
/dev/ttyUSB2
115200
debug
defaultroute
ipcp-accept-local
ipcp-accept-remote
usepeerdns
crtscts
lock
noccp
noipdefault
active-filter outbound
demand
idle 300
user ctnet@mycdma.cn
password vnet.mobi
mtu 1490
mru 1490
connect '/bin/chat -v -t10 -f /var/usb3g.chat'"
Code: Select all
ECHO ON
ABORT 'NO DIAL TONE'
ABORT 'NO ANSWER'
ABORT 'NO CARRIER'
ABORT 'DELAYED'
ABORT 'COMMAND NOT SUPPORT'
'' 'AT'
'OK' 'ATZ'
'OK' "ATQ0 V1 E1 S0=0 &C0 &D2"
#'OK' 'AT+CGDCONT=1,"IP","#777"'
#
SAY 'dial...'
'OK' 'ATD#777'
'OK'
I need your help ,thanks.