Archive for October, 2008

Android on Zoom

Thursday, October 30th, 2008

I had never touch Android before but it took only a day to get it running on a Zoom board. I think getting a new complete Linux setup running on a real device could be much harder although there were some bumbs on the way.

I mainly followed the instructions on the and on The JDK from my Debian Etch didn’t seem to work, so I had to download the JDK from and set up some environment variables. Once those were set the compilation succeeded without problems. I would have saved some hours if I had read the instructions properly in the first place.

The instructions were a bit vague on to do after the compilation was finished. Eventually I created the card.img that acts as a MMC/SD card and launched the emulator:

./out/host/linux-x86/bin/emulator -sdcard card.img -system out/target/product/ldp1/ -kernel ./prebuilt/android-arm/kernel/kernel-qemu

The emulator runs the real ARM root file system image with qemu so it fully matches the actual file system. The file system includes e.g. ssh so I could IRC with the terminal application but it doesn’t include e.g. cp, which seems a bit odd. The file system directory hierarchy looks completely weird and messy to me. It mounts a read only ramdisk as root and data, system and sdcard under it.

Android provides Android Debug Bridge (adb) that is capable of sending files to the root file system run by the emulator or giving you a remote shell, among other things. I used it to get more complete busybox there and tarred (no compression) the /data and /system directories to the fake MMC/SD card. If I had had a Linux setup that understands YAFFS file systems this would have been a bit easier since I could have used the original images directly without copying the content from the running emulator.

I set up an EXT3 root file system to a real SD card from the ramdisk, system and data tar balls and replaced the init.rc with init.omapldpboard.rc and booted the Zoom board with the uImage built separately according to the instructions.

The desktop (or home) is something new but the menus that open from the bottom actually seem quite traditional. The UI looks quite polished and is very responsive on the Zoom. Everything feels snappier than I would have expected. The Zoom doesn’t have WLAN and I didn’t find anything to set up the wired network with a quick search so I didn’t have a network connection.

I’m sure we’ll see interesting devices (in addition to G1) based on Android in the future.