First time setup: MC7455 with raspberryPi3.


I bought couple Sierra Wireless Airprime cellular modem(MC7455). I have PCIe to usb adapter boards that is used to connect the modem to raspberry PI.
When i plug in, i see the modem identified by raspberry pi and i also see wwan0 and wwan1 interfaces but when i try sending AT commands to modem usig miinicom, i donot get any response.
How can i find if the driver on RPI is correct ? AT+GMR doesn’t return anythig so how do i find the ker version ?
Is there a user guide or steps for troubleshooting ?

Also i read the AT_command_Reference document for MC7455 and it says the commands are password protected and are different for each carrier. Does anyone know who is the contact as i purchased the modem’s from Digikey.

Thanks in advance.

Hi Sachin,

Generally when MC7455 module is connected to Linux machine, check the module detected or not. i.e. lsusb or lsusb –t
Once the module is detected, then provide this command to get the USB ports info : ls /dev/ttyU*
Any one of the USB port will be your AT port and provide that port number in Minicom. So that you can provide the AT commands.

For further any queries , Please contact your Technical support in SWI to provide you the solution.

Thanks and Regards,

Hi Rex,
Thanks for your response.

This line gave me the clue to check all devices and found our ttyUSB2 responded to AT commands.

The module is detected on the raspberrypi. It is listed as “Bus 001 Device 005: ID 1199:9071 Sierra Wireless, Inc.”

Here is what I found: Hope this helps other who are experiencing similar issues.
There are 3 ttyUSB devices listed - ttyUSB0,ttyUSB1,ttyUSB2.
I was able to get it working with ttyUSB2.


Hi Sachin,

You probably already know, but you can receive GPS/GNSS -messages (NMEA) from ttyUSB1.

Br, Karppa