UNIX variants on HP Jornada Palmtops

We covered this a bit at the 2600 meeting last night. I don't have a lot of time to go into detail, but here's a quick breakdown.

Asmodian X got me hooked on Windows CE Palmtops back in late 1997. I picked up a floor model HP 300LX for cheap, and actually used it as my main computer (including Dialup BBS, Telnet, Mail, and web browsing) for quite a while. It was more than sufficient for typing my papers for class and interfacing with the UNIX servers. Asmo also had a Casio Cassiopeia running CE, so we tinkered with this stuff a LOT back in the day.

Later, at DefCon 6, we'd run into a guy with an HP 620LX. That thing had a full color screen and a significant boost in memory, not to mention sound recording ability. This all sounds cheesy now, but it blew away the devices we had with their four or 16-color greyscale screens.

As time has progressed, I've also acquired an HP 320LX (same as 300LX but with a backlit screen and more RAM), a Jornada 680e (Refurbished Dutch Railways model) and a Jornada 720.

The HP300's are currently packed away somewhere, but the Jornadas are alive and well.

I was considering NetBSD and Linux for this project, but I found out that the NetBSD project for these pretty much died once they could say "it boots!" You have to use a serial cable for the console. In other words, it's useless until someone ports wscons and some device drivers. So, I chose JLime Linux, which is still in active development -- the kernel build on my 720 (Mongo branch) is less than two weeks old!

To install JLime, you need a CF card that's at least 128MB. You create 3 partitions:

1. FAT partition usable from within Windows CE
2. ext2 partition for Linux to run from
3. Swap partition for virtual memory

You copy the bootloader, boot configuration file and zImage (kernel, etc) to the FAT partition, and then uncompress the jLime userland onto the ext2 partition. Since the files were compressed with bzip2 and BSD's tar utility doesn't know what to do with that, I had to uncompress it before using tar. Make sure you run tar as root (or with sudo) and with "xpf" or "xvpf" to retain the file permissions and ownership of the userland image.

Once you insert the card into the PDA and run the boot loader, all of the PDA's memory will be completely wiped, so all files and data on it will be lost. Windows CE stays in ROM so when you reboot, Windows CE will be back in initial setup mode.

I actually put the boot loaders and zimages for both the J680e and the J720 on the FAT partition, created two different ext2 partitions, and left one shared swap partition on my 2GB CF card. Had I been thinking, I would have made a third ext2 for a shared home directory between the two PDAs.

Right now, here's the status of them:
Jornada 680 running jLime (Donkey):

• Boots Linux, loads fine.
• The keymap is completely trashed (dutch keyboard layout) so I can't login.
  
• Apparently, the J680 can "suspend" while running jLime.
  

Jornada 720 running jLime (Mongo)

• Boots Linux
• Runs X with IceWM
• Various X Apps work fine (MiniMO Browser, aterm, etc)
• Recognizes PCMCIA Ethernet and 802.11b/g wireless cards
• Can't seem to use the network, even when configured properly (dhcp doesn't get an address, wireless cards can't associate to open, unencrypted networks, etc)
• Cannot go into suspend mode properly. The backlight stays on, limiting battery life.
• After halting, the PDA can't reboot without a hard reset (removal of main and backup battery at the same time)

So, it looks like jLime has a little ways to go yet, but it's a functional UNIX environment, at least on my Jornada 720. I just wish I could get the networking piece to work properly. I could almost live without a suspend mode, since many of my other laptops don't particularly like to suspend, either.