EM7455/7430 configuration using AT commands

Hi, I am new to the EM7455/7430 modems. Can someone point me to a typical sequence of AT commands to set up the modem for cellular data transfer? I have a AT&T and Verizon SIM card.

Basically I like to know the sequence of AT commands to issue to the modem after powering up the modem with the SIM card installed.

Also what are the AT commands to do a firmware update on the modem? I do not plan to use the firmware download application supplied by Sierra.

Thanks a lot! :slightly_smiling_face:

on linux:
(should return with OK)

on the host
or NTWK manager will automatically bringup the session

assuming you already installed the Sierra drivers (GobiNet and GobiSerial)

to upgrade the FW either use the linux SampleApps packed with the SDK or we have oneclick tools for Windows.

Thanks for your reply.

The EM7455 modem is attached to our custom ARM board running Linux 3.6.5, and we will use our Linux application code to setup and control the modem, and this includes doing firmware upgrade.

So our Linux app only needs to issue a single AT command to activate data transfer? How about configuring it to use the SIM card and SIM card password and etc? Sorry for my many questions since this is the 1st time I am working with this modem. :frowning:

I assume the cellular side will get its IP address from the wireless DHCP server. For the local wwan port, if I want to assign it to use a static IP, do I do a ifconfig on that port?

Yes, i have already cross compiled and built the Gobi drivers for my kernel.

So doing firmware upgrade can only be done via the sampleApps or via the OneClick Windows tool? How can I cross compile the sampleApps for my ARM board? I looked through the code and it appears some lower level code is not provided in source code.


During testing do not enable the PIN code, other than this you don’t have to configure the SIM.
You can either control the modem with AT or QMI commands. The SDK has sample apps and docs how to compile it.

“So doing firmware upgrade can only be done via the sampleApps”
“How can I cross compile the sampleApps for my ARM board?”
make sure to read the SDK docs.
You can try the ARM precompiled sample app.

Thank you so much for your tips.

I have successfully cross compiled the sampleApps for ARM. I am using the LITE SDK.

Back to my question regarding configuring the modem on bootup… when the modem boots up with a SIM installed, it will automatically get its WAN IP address via DHCP by itself, or do I need to configure it to do so?

For SIM APN, don’t I need to configure it to the modem?

On embedded platforms you have to run DHCP or manually hardcode the IP to the interface with ifconfig.
Most PC distribution will launch dhcp automatically through network manager.

“For SIM APN, don’t I need to configure it to the modem?”
it depends on the carrier.
Verizon will populate the APN over the air. Our ATT SKU will default the APN to “broadband”
on some carriers you will have to program the APN.


May I know what is the AT command to program the APN?

it is on our AT guide.

I have been trying to find the product ID for the EM7455 and EM7430, but can’t seem to find it in the functional spec. Would you advise the product ID for these 2 modems? I believe the vendor ID is 0x1199.

Thanks again for all your wonderful help!

Linux lsusb shows the modem’s VID/PID.

Hi, I am reviewing the AirPrime EM74xx AT command reference document rev 3, but I cannot find the at+cgdcont command. Do you mean at+cgdcont command?

Also I like to reconfirm that firmware update cannot be done using AT commands on the EM74xx modems. I only can find the at!BOOTHOLD command that reset and hold the modem to wait for the firmware image to be download to the modem. But I can’t find the AT command to actually download the image to the modem.