"unresponsive" keyboard

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Potato
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Iscritto: 06/04/2014

Sometimes my keyboard does not work, and the only thing that I can do that makes it work is to shut down the computer, turn off the power to it (and all the other peripherals), turn the power back on, and reboot. (Sometimes I have to do this two or three times.) It seems to be happening more often lately. This has happened with Trisquel v6, and now with v7. (I bought my computer and keyboard from ThinkPenguin, with version 6 already installed.) I would like to know what is causing this, and how to permanently fix it. Thanks.

lembas
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Iscritto: 05/13/2010

This also happens to me sometimes (on a non-TP computer). I've been trying to figure out what causes it but no success. For me it's enough to logout/login to make it work again.

Casey Parker
Offline
Iscritto: 02/05/2015

I've noticed the same. What kind of keyboard are you using? And
motherboard. Personally I'm using a Asus M5A57 board and a ... actually I
don't know who made my $5 keyboard.

On Fri Feb 20 2015 at 1:44:47 AM <name at domain> wrote:

> This also happens to me sometimes (on a non-TP computer). I've been trying
> to
> figure out what causes it but no success. For me it's enough to
> logout/login
> to make it work again.
>

lembas
Offline
Iscritto: 05/13/2010

This is an old HP laptop. Since this seems to happen on different hardware, my bet is it's a software issue.

doolio
Offline
Iscritto: 12/31/2013

I have suffered from this issue too running T6 on a Libreboot X60s and had to resort to what Lembas has had to do.

amenex
Offline
Iscritto: 01/03/2015

With a former used motherboard, I, too had to follow a ritual to restore keyboard access: Shut down, unplug power cord, press & hold start button, restore power, restart ... and sometimes repeat.

A newer used motherboard has a dead PS2 connection (never worked for me) so I applied a USB keyboard that occasionally stops responding, notably while booting up, but at other times, too. I just wiggle the USB connection ... if that's unsuccessful, I unplug it and plug it back in, and it works again. No need for a restart.

Those were and are Trisquel installations. One more example: On a Dell Inspiron, the USB mouse occasionally exhibits this behavior. That laptop has a feature that allows the built-in touchpad to be shut off when the USB mouse is plugged in, so I can unplug the USB mouse and plug it back in to revitalize it. Without that feature in effect, unplugging the mouse shuts down the *XP OS. Other USB ports are getting flaky, but I have to be careful about disconnecting those willy-nilly, so I follow the hardware protocol by asking nicely beforehand.

Sometimes, a cheap mouse's wiring may fail. I keep a number of spares handy. Keyboards don't get moved around much, but their wires could break, too.

Bottom line: serial ports are flaky and may become corroded, perhaps because their gold plating has been worn off. Remember that copper oxide is a semiconductor and its presence in an electrical connection will introduce a breakdown forward/backward voltage drop that will interfere with the serial communications protocol.

None of this has anything to do with software.

marioxcc
Offline
Iscritto: 08/13/2014

> Remember that copper oxide is a semiconductor and its presence in an electrical connection will introduce a breakdown forward/backward voltage drop that will interfere with the serial communications protocol.

You are confusing different concepts.

Breakdown voltage refers to a property of materials (when in a specific setup) that behave as insulators, and it's the voltage at which dielectric breakdown happens. After breakdown happens and while the current is enough, it will behave as a conductor (some materials are damaged by this, but others recover completely or almost so, such as SF6 and that's why it's used in switchgear). The voltage drop through an insulation in this condition becomes much lower (remember, now it behaves as a conductor) than the breakdown voltage (in practical cases, at least). This is why fluorescent lamps and arc welding machines (based on dielectric breakdown of the contained gas and air, respectively) need a large inductance or an electronic power supply to limit current, but a relatively large voltage to start the arc.

Semiconductor devices such as diodes are also said to have a “breakdown” operating mode: for diodes it's when they are reverse biased and there is significant current. However, we're not talking here of diodes or any other semiconductor device. It takes special preparation to make a material behave as a semiconductor in a meaningful way, even as a diode, whic is the simplest semiconductor device. Even galena radios required a carefully made contact for the primitive diode. Oxidation of copper electrodes makes the connection worser but it still obeys ohm's law.

Just a normal brown coat of copper oxides won't insulate a connection. It's normal to see working cable splices like that.

Maybe you have a hardware problem, but if so, then it's a different problem than what the other users here have, because theirs is temporarily solved by restarting and a bad contact won't become good by restarting the computer.

Regards.

onpon4
Offline
Iscritto: 05/30/2012

Well, that makes me feel better. This has happened to me, too. I assumed it was something wrong with my keyboard. I guess not.

When it happens, I usually use Onboard until it starts working again (usually a few minutes later).

amenex
Offline
Iscritto: 01/03/2015

marioxcc said:

> You are confusing different concepts.<

Not so fast; look here: http://savethenbn.com/res/CopperOxide.pdf

The specified contact resistance of a USB connector is 0.030 ohm. Let's say that the copper oxide rectifier at the copper/copper-oxide/copper junction has a 0.3 volt forward voltage drop. The equivalent resistance for a 0.5 amp signal current would then be 0.3 V/0.5 A equals 0.600 ohm, twenty times the specified contact resistance of 0.030 ohm.

amenex
Offline
Iscritto: 01/03/2015

Trisquel has a role, perhaps unintended.

Today my *inXP laptop's USB ports ceased functioning ... the USB mouse would not work where I usually plug it in, and nowhere else, for that matter. Then the touchpad stopped working; *inXP would not boot, not even past the black screen ...

Then I tried plugging in my Trisquel LiveUSB flashdrive, which booted up without hesitation, revealing that the mouse worked OK, even though plugged into that troublesome USB port. So I shut Trisquel down and tried *inXP again ... whereupon it started right up, mouse and all, as if nothing had happened.