Sunday, February 2, 2014

Getting OpenWrt to boot and wireless network to work

I'm back home, and a it's time to get things up and running here.

Our first goal is to get the system up and running with wireless support. We are going to do the testing using tftp boot and an image with embeded root file system.

I have spent a little time trying to learn the structure of OpenWrt and how devices are configured. Created a dts file for our device with the hardware specific parts and changed some of the boot scripts to support the device.

Building the image works fine, and it boots. So we are off to a good start here. For some reason I get decompress errors when booting from the uboot command line, but it works fine when booting from tftp on the main uboot menu (option 1). We might address that later, and find out whats wrong. But for now we are fine with just booting the normal way.

And after digging around a bit, I find out that while the SoC is supported, but the wlan is not. Which leaves us with a few options, use the proprietary driver (and therefore also a old kernel), write a driver for the wifi or use the uClinux environment that Kingston used. For now, I will go for the latter.

I guess I should have checked this out before spending a lot of time on preparing everything else for the image. So no OpenWrt, for now. Time to get a SSH server to our modified stock image.

And last, but not least. My pal Larry has created an OpenWrt wiki page for the device. My device seem to have a different flash chip (and 16MB to play with), but thats all I have to comment on it. Well, that and of course to say good work.

So thats it for now I will try to make an flashable image or something similar next time. Yes, and I almost forgot, I also want to use the device for tethered shooting with automatic backup to the SD-card and/or online services. I got this NOOK HD+ for cheap, and I decided that it would make a great device when shooting tethered. I could of course just do that using a Raspberry PI, since that already works fine, but whats the fun in that.


  1. Hi, the source code of wifi driver for MT7620N SoC is available (although not GPL'd) from a project repository at googlecode called "rt-n56u" (which also supports rt-n14u, whose SoC is mt7620n). Porting that piece of code to OpenWrt would be an easy way to make wlan work.

  2. Awesome, thanks John. I'll look into it when I get time.