Category Archives: Netbook

It’s an ENTS Miracle

The second worst thing about this time of year is the static charges that build up due to the complete lack of humidity. The worst thing about this time of year for a geek is the hardware you kill because of those static charges.

I almost killed my netbook today. I’d just finished burning a CD with a USB attached external and when to close the burning app and *ZAP*. Hurt like all hell and the netbook immediately powered off. I unplugged the USB drive and fired up the netbook, all seemed OK. I’d zapped the thing in the past and it’d been just fine so I wasn’t too worried at first.

And then the back-light cut out just after I remarked that “I’m surprised I haven’t killed this thing yet”. 2 minutes later, the back-light comes on again. It cycles back and forth time and time again, each time the on period becoming shorter and the off period becoming longer.

Out of an amazing stroke of luck one of the other guys in the hackspace today not only had an Acer Aspire One 110 with him, but he also knew his way around an oscilloscope too. I pulled my netbook apart and we attached my LCD module to his Aspire One and let it ride for a while. It behaved perfectly. So we started thinking the issue wasn’t with the back-light but either the power provided by the motherboard or with the dimming signal sent to the display module. With Matt’s netbook still powering my display we spent some time noodling around with the oscilloscope and with the help of possibly the correct data-sheet for the LCD module we verified that the LED back-light was powered by +5V and the brightness is controlled by a +3.3V PWM signal. Once we determined what the cause of the problem was, either the +5V line cutting out or the +3.3V signal getting mangled we could route around the problem. If it was an LED power problem then I could borrow some +5V from the USB lines to the webcam. If the +3.3V PWM signal was borked I could just wire the +3.3V line that fed the LCD module to the brightness control line and deal with a permanently-100%-bright LCD. With all that determined we shut down Matt’s netbook and connected my LCD module to the internals of my netbook.

I fired it up and waited for it to fail. And waited…. and waited… and it hasn’t happened since. I put everything back together and it’s been behaving. All that planning and geekery and I don’t even get to claim to be responsible for the resurrection of this netbook. Apparently I have a self-healing netbook. It’s an ENTS miracle.

A fix!

Disabling a udev rule that calls part of libata and does some other magic seems to prevent the HSM Violation. This is a temporary workaround until the kernel bug is resolved. Infohere.

For the record, this is on an Acer Aspire One ZG5 with a SuperTalent FEM32GF13M 32GB SSD running Debian/Squeeze and 2.6.30-2-686.

Good way to start the day

[ 121.816110] ata2: lost interrupt (Status 0x58)
[ 121.820044] ata2: drained 2048 bytes to clear DRQ.
[ 121.823588] ata2.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
[ 121.823697] ata2.00: BMDMA stat 0x4
[ 121.823821] ata2.00: cmd c8/00:08:d5:2c:ce/00:00:00:00:00/e1 tag 0 dma 4096 in
[ 121.823829] res 58/00:08:d5:2c:ce/00:00:00:00:00/e1 Emask 0x2 (HSM violation)
[ 121.824093] ata2.00: status: { DRDY DRQ }
[ 121.824240] ata2: soft resetting link
[ 121.996468] ata2.00: configured for UDMA/100
[ 121.996507] ata2: EH complete

To be fair, I noticed it last night but I didn’t bother looking into it. When time allows today, I guess.

Netbook Upgrades

A few months ago I was having issues with the keyboard on my Netbook. I found some keys just simply took more pressure than others to register a hit and I found that results of my typing looked like I was from myspace.

Ebayed a new keyboard with a standard layout instead of the international layout and that problem was solved.

Shortly after that, the power adapter bit it. Ordered a new brick in through a local shop and all is well. Bonus is this one uses a double barrel cord instead of a triple barrel cord and is physically smaller so it’s easier to pack around.

And last but not least, I picked up an 9-cell extended battery from DealExtreme. I found that the 3-cell that came with my AA1 just wasn’t enough to be willing to leave the house without the power adapter. Now instead of 2ish hours of battery life I can run around with 6+. Not bad for $55.

With the above issues resolved I’m finding I like the netbook more and more. I spend less time on my workstation at home, and I leave the work-laptop at work unless I’m going on the road for more than a few days. I’d tried out Ubuntu Netbook Remix 9.04 and it’s stuck. I like the netbook launcher over default gnome. This has definitely been one of my more successful toy purchases to date.

On TMPFS on the Acer Aspire One

I’ve found FireFox3 to be rather slow on mouse and a bit of reading shows that it’s primarily due to how disk i/o heavy FF3 is. SQLite backed this and that, it’s more than the poor little SSD can take. However with 1.5gb of ram there is a solution. TMPFS!

I’ve mounted a ram-backed TMPFS and run Firefox, Thunderbird, Liferea and Pidgin out of there. It’s made a huge difference. I started with the instructions from here, and have since modified the setup over the last week.

Step by step, this is what it would take to recreate what I’ve done. As your regular, browsing user:
$ mkdir ~/.tmpfs

Then as root add the following to /etc/fstab, modifying it for your username, uid, and gid:
my-tmpfs /home/$USERNAME/.tmpfs tmpfs size=200M,noauto,user,exec,uid=1000,gid=100 0 0

With that done I modified the shell script to read as follows:
# Change this to match your correct profile

cd "${HOME}/.tmpfs_backup"
if test -z "$(mount | grep -F "${HOME}/.tmpfs" )"
mount "${HOME}/.tmpfs"

if test -f "${HOME}/.tmpfs/.unpacked"
rsync --exclude='Cache' --exclude='.unpacked' --exclude='lock' -r "${HOME}/.tmpfs/" .
cd "${HOME}/.tmpfs"
cp -r ${HOME}/.tmpfs_backup/* . && touch .unpacked

I named it tmpfs_rsync and put it in ~/bin. That’s right, no more tar for this guy. I found that after adding Thunderbird, Liferea and Pidgin into the mix, I was creating a sufficiently large enough tarball that performance would drop through the floor every 5 minutes as it backed up the tmpfs. Speaking of every 5 minutes, the respective crontab line for my user:
*/5 * * * * ~/bin/tmpfs_rsync

Make the script executable, and execute it once to mount the tmpfs and create the .unpacked lock-file of sorts:
$ chmod u+x ~/bin/tmpfs_rsync
$ ~/bin/tmpfs_rsync

With that done, all that’s left is to copy what you want to the tmpfs, then symlink it back in place. In the case of Liferea:
$ mv .liferea_1.4 ~/.tmpfs/liferea
$ ln -s ~/.tmpfs/liferea_1.4 .liferea_1.4

I repeated the above for Firefox, Thunderbird, and Pidgin and bob was my uncle. Make sure tmpfs_rsync executes once before shutdown and everything is backed up.

There are a dozen aborted posts under drafts

All of which I want to finish, none of which probably will be. I think Ze is right, if you have a neat idea just throw it out there now. To hell with trying to release it when it’s ready just punt it out the door and see what happens.

There’s stuff in there I would liked to have written about at the time, and I could do some small posts about them but I don’t know that it’s all that engaging to do so. So fuck that noise.

I saw Richard Fucking Stallman, a few weeks back, give a talk on how Copyright harms society. Nothing unexpected, I got to ask a question and he interrupted me as I pretty much expected he would.

A few days later I bought an Acer Aspire One. Upgraded it to 1.5gb of ram and soldered in a bluetooth adapter. Wiped whatever the hell distro they put on there and installed Debian Sid. Happy times.

The Soekris is coming along, it’s doing all routing at home quite handily and I’m working on asterisk. Once that’s done I think it’s time to ditch the personal cellphone. I’m tired of giving rogers money. The number will be ported to the VOIP account and people who don’t get the new mobile contact number immediately will have to accept voicemail and email as contact options for me.

Further to that, I think it’s time to ditch the equipment at the colo. Nothing I do right now justifies a half-rack of equipment, I could do everything I do currently in a rented VM, so that’s the plan.

It certainly does sound like I’m trying to cut expenses, and that’s because that’s exactly what I’m trying to do. I had a plan for this year, I think it’s about time I made it happen.

Other news, the Golf was broken into this week. They got away with a flashlight and a couple of car chargers. Fuck them and everyone who questions my carrying the tactimurse.

Time to stay angry.