Sunday, September 11, 2011

Always Check the Lowest Common Denominator

I've been going through some rounds with Asus tech support/customer service the last couple of months. Two RMA's and a brand new unit later, I have resolved the issue. I must admit it is a slightly embarrassing fix. It is a true example of making a mountain out of a mole hill in the technology industry.

I can't believe I missed this fix for so long, I can't believe my older brother who works on computers didn't think of it sooner, but really - I'm pissed off that the Asus repair facility didn't think of this before replacing the motherboard and screen in the netbook.

This morning I had the bright idea to boot up the T101mt again, but this time after I hit the power button I press function+f6 to toggle the brightness setting on the screen up. Sure enough the screen clicked right back on.


I don't think I have ever felt so stupid. It appears the recently added backlight code for Enlightenment was simply turning of the T101MT's internal display by default.

This is just a friendly reminder to everyone else out there that when debugging something - don't just skip over the lowest common denominator. It could save you a world of headache.

~Jeff Hoogland

15 comments:

  1. Thanks for figuring that out. I'm glad there's an easy fix.

    Now the question is why it happened to the T101MTs and not to every other backlight in the world. I still suspect ACPI, which is complicated at best and malicious by design.

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  2. Don't worry Jeff, this happens sometimes, even for genius :) (i'm pretty sure Bill Gates would agree!)

    Anyway, i think your first reaction was like... This (shame on Iron Sheik :P) -> http://www.youtube.com/watch?v=4HeSsfSmwSk

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  3. Most obvious is always the hardest to find. Congrats for working this out. In the meantime I tested latest Bodhi on Acer Aspire One 522, hope it will be useful. To properly boot, you need nomodeset option in grub menu entry, otherwise you'll get only colour garbage on the screen. Choosing Laptop/Netbook results in SEGV every few seconds. It's little better in the Desktop profile, but there's sometimes SEGV during logout. And after few reboots netbook hanged before BIOS, but the screen wasn't whole black, there was blinking cursor on it.

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  4. Wow petrek sounds like something is wrong there in a bad way! Please open a support ticket on our forum if you'd like help debugging :)

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  5. Ok, hope that this netbook will not sing to me in a thin voice "I was burned to make you happy" ;) And to be honest, I even managed to segfault terminal in debian stable, so maybe all this is only my luck or (seg)fault ;)

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  6. Same thing happened on a friends asus netbook. She was running windows 7. Don't ya just hate it when that happens?

    By the way, I love bodhi Linux! You guys have done an outstanding job! Thanks!

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  7. This is also a major reason I don't delete Windows if it is already included in a computer purchase. It lets me quickly know if something is Linux specify.

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  8. ".... Windows if it is already included in a computer purchase": ditto, though I do delete it and just leave the recovery partition as proof; the OS gives me proof of payment for codec, font licensing/use of etc.

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  9. Running Windows has actually been bad news for me. I was once given a new laptop by my school. Everything worked with Debian but one day some colored lines showed up from a defective cable. Running Windows also showed the colored lines and TURNED WIFI OFF. To turn it back on, I had to boot Windows, make it attach to a network and hard off the laptop by holding the power button down or yanking the battery. There are lots of other horror stories about Windows deleting grub, etc.

    To avoid these problems, I only buy hardware I know will work with gnu/linux and pave Windows over out of the box. I can check that hardware works by researching online or by going to a store an booting a CD or USB drive. If it does not work, I take it back and tell the store why. A computer that only works with Windows is not a working computer.

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  10. Jeff anyone that has been working with trouble shooting computers for a while has had one of these moments. I believe that is why Webster's Dictionary allowed in Homer Simpson's famous "Doh!" On the bright side you have some new components and a fresh outlook.

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  11. Been there with the t101mt. I was pretty sure I'd killed it too. A lot of frantic button pushing went on.

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  12. Hehe, I've done my share of this, too. Once I thought I was being persecuted in a Windows-only place for using Linux... had them check dhcp settings etc. -- until I noticed some funny guy had removed my ethernet cable (might be the janitor or something...)

    Well, well... happens all the time... with new distro versions, even and specially with the recent releases, my hardware gets unrecognized. In this case, I know it's not the hardware's fault: older legacy Nvidia drivers are not compatible with recent Xorg versions.

    Regarding Bodhi, congratulations on an excellent work. If I may suggest, and sorry if it already has them, it would be good to have meta-options to install more commonly used software. It's ok to make a lean distro, but most people will want e.g. Libreoffice.

    Also, you might want to base it on Debian; I perceive Ubuntu as changing a little too fast for distros which are based on it.

    Again, a most impressive work and let's hope Bodhi attracts more users to Enlightenment, which in turn will help it advance faster.

    Sp.Bob

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  13. Bob, Couldn't agree with you more on the software packs. We have two of them on our software center - http://www.bodhilinux.com/software/doku.php

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  14. I've gotta side with those here calling out ACPI, but I've also gotta add one to that: APIC.

    In my case, it wasn't a graphics issue, but rather a couple of systems with Realtek 8139 & 8169 NICs (ethernet adapter, onboard) that would fire up just fine, grab an IP address from DHCP, and then all traffic would halt altogether. Diagnostics looked good, except that nothing was pingable, even the outside of eth0 which should be no different than pinging localhost.

    I discovered this problem on Ubuntu-10.04, and have seen it present in several Ubuntu based distros since.

    the trick to fix it? edit /etc/default/grub and replace the default boot line (quiet splash) with: verbose noacpi acpi=off ipv6.disable=1

    this puts the boot into debug mode, disables the buggy APIC, kills ACPI so that the BIOS cannot interfere with device power management, and disables IPv6, which is known to cause problems in Sooooo many apps. Around my work, we have to kill IPv6 because it causes BackupExec Remote Agent for Linux to fail.

    Anyways, yeah, I could see an ACPI change causing a problem like that, but in this case, it looks like the Backlight module is definitely the culprit.

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