Removing the Ubuntu 11.04 launcher bar

In Ubuntu 11.04 (Natty Narwhal):

• Click the far top-left button to bring up the search dialog.
• Type "login" without the quotes and click on "Login Screen".
• Change "Select Ubuntu as default session" to "Select Ubuntu Classic as default session".
• Log out and back in.

Congratulation, you have removed the abomination. Prepare for 11.10 where they will no doubt remove Ubuntu Classic as an option.

Acekard 2i

I recently acquired an Acekard 2i for use with my DS Lite. I ordered the Acekard from r4i.co.uk (who are actually quite cheap for a lot of accessories) and got a 2GB microSD card for an extra £1 in the bundle. They also have other bundles with larger cards (or no card). The microSD card is needed because it's where you put all your precious files. There is meant to be a microSD reader in the bundle but I didn't receive one, I'm waiting for a response from them on that. Below is my quick guide to getting yourself up and running if you decide to get one for yourself. It's quite easy really.

Some features of the Acekard 2i in brief:

• No DS flashing or passkey/passme/passwhatever device needed.
• Supports all current DS variants (right now that's DSi, DSL, IDSL, DS and IDS).
• Supports any brand of microSD card (unlike some older devices which had timing constraints). There is a size limit, but I can't seem to find it on the site, I believe it was around 32GB.
• Older devices required software to be recompiled or patched for each different device it was run on, the Acekard handles this automatically.
• Can be used as a passkey in order to boot slot-2 flashcarts (for GBA experimentation), including the 3in1 cart. No need to worry about manually flashing your image to the slot-2 cart because the Acekard does this automatically when you boot a GBA ROM.
• Supports soft-reset, Download Play, and Wifi.

In terms of ethics, I know what you're thinking: "But Kemp, surely you don't condone playing pirated ROMs of DS games?" And no, no I don't. Sure, the Acekard has that capability, but this is one of those things I buy just to mess around with homebrew, and usually try to write a bit of my own at some point. The DS has a lot of nice features including two screens, one of which is a touchscreen, and wifi capability. Who wouldn't want to have a poke around on that? If you want help using it to play pirated games then you need to go find help somewhere else.

Setting up the Acekard 2i

The first thing you need to do is go and buy yourself a microSD card if you didn't order one along with the Acekard itself. It requires one for its own software, and you can't really do much without your own files anyway.

You should download either the official OSMenu software, or the alternative AKAIO software (which is a branch of the official software and widely regarded to be superior). This should be placed in the root of your microSD card. At this point insert the microSD into the Acekard and the Acekard into your DS, boot it, and check it works. If it hangs at the "Loading" screen then you didn't copy the software correctly.

That's basically it for the system software. Check out the options available, and make sure to change the options restricting the file types shown (you want the "All files" option).

Adding homebrew

I created a folder called "homebrew" in the root of the microSD card for this purpose. To get going you simply have to copy the .nds file for the program to this folder, boot up AKAIO, navigate to the homebrew folder, and click the file. It should be launched and (hopefully) work nicely. In general you can ignore any instructions to use DLDI to patch the software, as the Acekard handles this automatically for you.

Some nice software I've used:

• Moonshell (everyone knows this)
• DSNotes (I can't seem to find an "official" page)
• Pocket Physics

Writing homebrew

A good run-through for this is at CoderJoe.net. Surprisingly, this is one of the few times (the only time?) I've seen a cross-compiler toolchain that is easier to set up in Windows than in Linux. Well wonders never cease?

Adding Python

The good bit ;-) Download the dspython binary and copy it to your homebrew directory. This will automatically run the script at /python/main.py when it is executed, so create a "python" directory in the root of your microSD card and place a script there. As an example you can download the framebuffer demo given on the dspython site. At some point I will write a browser type script to place there that allows you to select another script to run.

There is a serious lack of documentation, but if you check out their svn tree then there are a some demos. In general though, the functions are named exactly the way they are in libnds (see above), so any documentation and demos for that should be fairly easily translatable into Python (within the constraints of what has been wrapped).

Final notes

As usual, GBATemp.net ran a good review of the device.

If anyone needs a picture for something I've mentioned then add a comment and I'll see what I can do.

OL's eeePC

Overlord has put up a post detailing how he got his eee PC 900 set up with Ubuntu (an eee PC specific version that somehow still requires a lot of modification to work properly). Looks like a useful post, otherwise the info is scattered around in different places. He updates it as he finds things, so check back occasionally just in case =P

LyX Crashes Under Ubuntu Hardy

Application: LyX
Distribution: Ubuntu 8.04 - Hardy Heron
Problem: Crashes opening valid .lyx files

I had a problem recently where LyX was crashing every time I attempted to open a file (through both the file open dialog and double-clicking a .lyx file). After some hunting around Google I found the following solution.

It turns out that the problem was a version mismatch with another package I wouldn't have even thought of looking at. I like to have all the repositories checked in my software sources list, as do a fair few people it seems, and this was the source of the problem. In Hardy Backports is version 4.4 of the Qt libraries, and LyX does not like them at all. The problem seems to be particularly focused around the loading of eps images, which are almost every document I produce, thus the near-constant crashing. I managed to force a document open by launching in excess of 100 instances of it simultaneously, but that's so ridiculous I don't think anyone could think of it as a workaround.

Anyway, the solution is to uninstall any qt4 related packages (do a search for qt in Synaptic and they will be fairly obvious), and uncheck Hardy Backports. LyX and Skype will be removed when you do the uninstall, so put those back on afterwards and they'll bring in the correct version of the Qt4 libraries.

This also solved a problem I was having with GnuCash's icon not displaying. This was fixed on two computers via this method, so I don't think it was coincedence.


I will add some links to relevant discussion when I have a moment free.

More Audio in Ubuntu

The first part of this is an addition to my earlier post on audio in Ubuntu. If you want a bit more detail about what you're doing with that fix then check out the original source, which also has some other useful links. After applying the fix I had problems with my sound crackling rather more than I like to hear. If you have similar problems then check out the Dmix page on the ALSA wiki, specifically the "Still Hearing Stuttering?" and "Comments" sections near the bottom. I haven't tried that extra modification myself (I was in the middle of something at the time and just disabled mixing again), but it looks promising and easy to do. That page is a goldmine of information about modifying your setup so it may be worth taking a bit of extra time to read through.

Ok, with that out of the way, how about visualisations in Rhythmbox? I use that as my audio player and I'm quite happy with it except it only has two visualisations available (I don't use them much, but they do amuse me so I like to have a few). Luckily information on this is easy to find and it turns out you need to install the libvisual-0.4-plugins package. I had a slight problem with one of them causing Rhythmbox to crash, but that may just be my setup as I don't recall seeing any warnings.

Enjoy :-)

Audio In Ubuntu

This is one for those of you fed up of only being able to play sound from one source at a time in Ubuntu. In fact, only being able to have one application open that may want to play sound.

"Hmmmm... I want to watch this video clip. Oh wait, I'm playing music so I can't. I know, I'll pause the music. Oh, still no luck. Stop the music? Oh, freakin' great. I'll just completely close the music player shall I?"

"I can't play music, what's going on there? Oh, I know, I had a flash animation open in my browser several hours ago and it hasn't released the sound device yet..."

Anyway, there's a new blog here which has all the answers you need (the only answer you need to be precise).

Enjoy your new freedom :-)

Loopback Partitions

I guess moaning about Wubi previously pretty much guaranteed it would fail on me, and true to form it has. I don't know if this is actually a Wubi issue or a Gutsy development issue as I haven't had much time to check out reports yet, but I figured I'd present an easy solution for an easy problem, just in case you hadn't done this before.

The backstory is I grabbed the latest package updates (beta Gutsy gives me up to a couple hundred a day) and later ended up hard-resetting the system after a lockup that refused to be fixed another way. At this point serious alarm bells are ringing (especially if you have rebuilt three corrupt partition tables on two machines at various points). Anyway, no corrupt partition table this time, but Ubuntu refused to boot with Grub giving a message about "unknown device string". XP was still fine so I booted into there while I considered my options. Not knowing enough about Grub configuration to fix the obvious error I decided to directly mount the disk image under Windows and grab some files I needed that way. Unfortunately I couldn't make this work as it insisted the image wasn't formatted (I had already installed the Ext2 IFS so that wasn't the problem afaict). In the end I copied the entire image onto my USB drive and took it home, where I used the easy solution:

sudo mkdir /mnt/temp_home
sudo mount -o loop -t ext3 home.virtual.disk /mnt/temp_home
cd /mnt/temp_home

Oh look, there's all my files. One happy Kemp :-) Now to fix the booting problem...

Wubi Dangers

So yesterday I had a rather tense time trying to help Overlord fix his laptop. He covered the story in his blog but I figured I'd blog the solution we came up with here too for everyone's benefit.

He had installed Wubi (warning: read this first and remember it is an unofficial beta product) on his new laptop and it was all working fine. That is until the next morning when he switched his machine on to find it stuck in a loop running the POST, searching for an OS, failing to find it, and rebooting to start the process again.

The first thing to do was obviously a Google search, which resulted in several hits. The first hit gave us a vital clue: partition boot sector corruption was occurring. After some fiddling this eventually triggered a memory of a similar experience I had once with Wubi causing partition table corruption after a lockup and unsafe reboot. That time I had used a tool to manually recreate my partition table (luckily I didn't have a complex setup) and write a functioning boot sector to the relevant location. That wasn't an option this time as the tool wasn't immediately available, so I suggested my old backup option. This involved using the XP install disc to fix the corrupted boot sector via the Recovery Console. I only had an XP Pro install disc and the installation on the laptop was XP Home, but luckily that isn't an issue for this type of operation. The first thing we tried was chkdsk to find any obvious filesystem errors, but this did nothing. Running map showed why: the filesystem type could not be detected (a previous data gathering mission [not mentioned above] with an Ubuntu Live CD was able to extract the filesystem type strangely). Knowing that the most likely cause of the troubles was the partition boot sector being corrupted, the next program to run was fixboot, which confirmed the corruption, detected the filesystem as NTFS, and wrote out a new (supposedly working) copy of the boot sector. With fingers crossed we rebooted and waited... only for it to continue happening. Suppressing some combination of cursing and tears we booted once again into the Recovery Console for another try. Again the first thing to be run was chkdsk and this time it actually did something and mentioned fixing some errors, though it didn't say what they were. At this point I was silently praying it knew what it was doing because if it had picked up the wrong filesystem type it could be happily trashing the files on it. map was then run again and still no filesystem type being shown for that partition ("I have a bad feeling about this", praying again I wasn't right about chkdsk being bad). As a last ditch we ran fixboot again (again, seriously, fixing this was enough to induce OCD in someone) and then map and... WOOT! The filesystem was shown as NTFS. Crossing our fingers again for the reboot we waited for the POST stuff to happen and then... Windows. Lovely lovely Windows. I never thought I'd say that. Overlord understandably purged all trace of Wubi from his system and vowed never to use it again.

I think the magic combination was the fixboot-chkdsk-fixboot, though I can't be sure. I certainly don't want to have to do this again.

I should note that I am using Wubi on my machine here (not only that, but running Ubuntu Gutsy beta under it) and I have only had the problem resulting from the lockup-reboot, but I may very well have just been lucky. Basically, an OS with reverse-engineered drivers for a badly documented filesystem with no journalling/transactions available running under a beta installer/loader isn't the best thing to have on your machine. You have been warned.