Sierra Aircard 320U auto connect

I needed to setup my AirCard to be able to automatically connect to the internet.

1. Connecting to modem
Open a Linux terminal window connect to modem using command
minicom –s

AT command port uses standard settings 115200 bps and 8 bits none parity, 1 stop bit (115200-8N1)
Then, go to Serial port Setup and use : /dev/ttyUSB2 or /dev/ttyUSB3 ** depending of modem and firmware.
To verify modem is responding type ati5. It shows modem IMEI and Firmware.
Manufacturer: Sierra Wireless, Incorporated
Model: AirCard 320U
Revision: X1_4_5_0AP R5267 CNSZXD00000140 2012/07/02 13:48:56
IMEI: 357272044870768
FSN: CC40993248910
3GPP Release 8

2. Setup the APN
Verify if there is a profile created using command at+cgdcont?
+CGDCONT: 1,"IP","telstra.datapack","",0,0
+CGDCONT: 15,"IP","telstra.internet","",0,0

Most Branding cards have already a profile 1 created with standard APN. If there is not profile or SIM account uses a different APN. It is possible to modify or create a new profile using command
at+cgdcont =,"IP","APN".

Where “PID” is the profile id that identifies the profile, typically profile 1
The modem should respond with "OK"
Telstra: at+cgdcont=1,”IP”,”Telstra.datapack”
Telstra: at+cgdcont=15,”IP”,”Telstra.internet”

Optional step: To change the Authentication method with the Carrier you can use the following commands:
3. Set Radio On
When using the modem in different computers it could inadvertently have set the Radio off. To enable the Radio use command: at+cfun =1. After that, it should have power light on solid and Data light flashing. On CDMA modems use at!pcstate=1
Note: To set the radio off use command at+cfun=0 as a result the two lights will be off.
4. Establishing a manual connection
The following commands can be used to connect or disconnect on direct IP modems
To manual connect: at!scact=1,<pid>
To manual disconnect: at!scact=0,<pid>
Optional : Setting Auto connect in default profile.
Modem can auto connect after powering up or resets using the default profile.
To set a default profile use the following command: at!scdftprof=<pid> You can enable Auto connect in default profile using command: at!scprof=,"",1,0,0,0.

5. IP address obtained by carrier
To check the IP address obtained by modem from the network use: at!scpaddr=<pid> For Example to Check IP address on profile 1 use command: at!scpaddr=1

6. Passing the IP on the computer
Depending of the modem, it may not have the DHCP enabled by firmware.
ifconfig wwan0 up **
ifup wwan0

It will show wwan0 interface with same IP address s as shown in step 5.
** if it shows error "interface wwan0 not configured". We suggest adding the following lines in the interface file located: /etc/network/interfaces using any text editor
auto wwan0
iface wwan0 inet dhcp

7. Summary
Summary of command s to create a Profile and make a manual connection using profile 3

Summary of commands to create a Profile 3 and using Auto connect feature
at!scprof=3," ",1,0,0,0

8. Command to check modem status: at!gstatus?

Please Register.

If you wish to add comments.