Turns out a recent update to ChromeOS has added GSM support for the Gobi 3G chip that’s in the Cr-48, and it’s working just great.

Since some people seem to want to run their Cr-48 on AT&T and so on, I figured I should share. Turns out, it’s really easy to enable. You need to be in developer mode, but that’s pretty much the only requirement. As usual, you do this totally at your own risk and I’m not responsible for anything that might go wrong. Basically, the standard disclaimer crap. With that said, here’s the howto:

1. Pop your SIM card into the slot under the battery (must be a full-size SIM, microSIMs you’ll just lose in there, fine if you use an adaptor though)
2. Make sure you’ve enabled developer mode – do this by flipping the switch under your battery
3. Once you’re booted into developer mode and logged in, press Control-Alt-T
4. This opens crosh, a limited command shell. Since we’re in developer mode, we can get a full shell. Type the word shell and press enter.
5. You’ll get a shell that starts with ‘chronos@localhost / $’. Once you’ve got this, we can type in the command that flips over to GSM.
6. Type the following command: modem_set_carrier “Generic UMTS”
7. Wait a couple of minutes, then you can exit the shell by typing exit twice.
8. Your 3G should be usable assuming you have an active service plan on that SIM card, and that ChromeOS knows your APN settings.

This is all totally unfinished right now, I just saw that the changes had shipped in a recent update and decided to see if they worked, turns out they do. However, there are a few drawbacks:

• Your APN details have to be part of a hardcoded list list in flimflam, you can see this list here.
• Your carrier name won’t appear in the UI, nor will any usage details. Don’t complain if you run up a huge bill, same deal here as tethering when it comes to data usage.
• It’s totally experimental, so it might break totally unexpectedly.

If you’d like to switch back to Verizon Wireless, do the above again but instead of “Generic UMTS” use “Verizon Wireless”. There are a few more options here that you can try, but I don’t know if they work. Feel free to give them a shot. “AT&T”, “T-Mobile” and “Vodafone” are also valid options.