Sunday, May 1, 2016

Notes on the Gobi2000 in a Thinkpad X100e

The Qualcomm Gobi2000 is an internal Mini PCI Express 3G modem. It was used in a variety of machines including the Lenovo Thinkpad X100e.
It's a bit unintuitive to set up (to say the least) so I decided to write this post. Maybe it'll help someone else out there.

So right off the bat unless you're a Verizon customer do NOT just install the driver from Lenovo's site because it will default to loading Verizon's firmware. See: https://support.lenovo.com/en/en/documents/migr-75433

If you already did you can uninstall and follow the instructions above or you can open the file: C:\ProgramData\QUALCOMM\QDLService2k\Options2k.txt and edit it.

The text file contains the path to 3 binary blobs which get loaded into the card's ram when the driver loads. Apps.mbn, AMMS.mbn and UQCN.mbn 
You just need to change which directory the images are loaded from. \1 is the Verizon firmware. For a full list see the support link above.
Note that to load the generic UMTS firmware you need to load Apps.mbn and AMMS.mbn from \UMTS and UQCN.mbn from \6 because consistency was not the developers' strong suit.

Also unless you're on a CDMA network that doesn't use a SIM card and requires an activation procedure instead do NOT install "Mobile Broadband Activation" either.

DO Install "Hotkey Features Integration" http://support.lenovo.com/en/en/downloads/migr-74261. As far as I could tell it's the only way to enable the WWAN antenna. Fn+F5 brings up the radio power controls. It's also a separate executable so you can create a shortcut for it if you like. The naming is pretty straightforward, look through the installation folder in Program Files.

A note on all the abbreviations you can come across while setting up a 3G connection:
UMTS is the name of the whole 3G network technology, WCDMA is the name of the radio access layer used by UMTS networks. From a setup perspective they're pretty much interchangeable. HSDPA or HSUPA are high speed data services offered on a UMTS network. HSDPA offers faster download and HSUPA offers faster upload speeds. Together they are often referred to as HSPA. HSPA+ and Advanced HSPA+ are further iterations of this technology that offer even faster speeds.
And of course GPRS and EDGE are considerably slower data services running on a 2G GSM network.

Unlike Huawei or ZTE modems the Gobi2000 doesn't have a straightforward way to set which network and data service it should prefer. The automatic selection will be fine in most cases but sometimes you just want to force the setting. Like let's say the 3G network's signal is really weak and flaky but it's still faster than the 2G network that has good signal.
Apparently there is a method with the slow and clumsy Lenovo Access Connections tool but from what I can tell the setting doesn't persist.

I'm fairly certain the Lenovo tool just issues a manual network selection AT command. You can do that yourself (you can even add it as a pre-connection command to the Windows mobile broadband connection. It's there on one of the properties pages)
You can tell the modem to connect to a network by name but it's a better idea to use the network ID because carriers will sometimes name their 2g and 3g networks differently.

AT+COPS=1,2,"#####",0 (where ##### is the network id) will connect to the 2G network of the carrier

AT+COPS=1,2,"#####",2 will connect to the 3G network

To get the network ID you can issue AT+COPS=? to do a network scan (it will take a while) the 5 digit numbers in the list will be the network IDs

You can query the current operating mode with AT$QCSYSMODE?

On the 2G network I got simply GSM as the reply
On the 3G network WCDMA + HSDPA + HSUPA (which Windows listed as HSPA in the network list)
On another 3G network simply WCDMA (which Windows listed as UMTS)

You can also query the current network with AT+COPS?
You'll get something like +COPS: 1,0,"Network-Name",2

Note that the modem will return ERROR for most commands if it doesn't see a SIM card or if the radio is powered off.


UPDATE: It turns out that you have to use the terrible, slow, memory-hog Lenovo Access Connections tool anyway. The built-in Windows connection manager just gives a nondescript connection failed error every time :-(

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