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Linux says "unknown scancode" for all keys

From Justin Ekis

Answered By: Thomas Adam, Karl-Heinz Herrmann, Benjamin A. Okopnik

Hello I went to look at the kernel messages with dmesg today, but surprise! All that I got was line after line of this:

keyboard: unknown scancode e0 64

dmesg and /var/log/messages are just about useless, flooded with that.

It's the same scancode every time too. the command showkey -s shows that my wireless keyboard does send an extra scancode after each key along with the normal scancodes. This is apparently some kind of status notification. I was surprised that the keyboard worked at all since it required a special driver under Windows so I almost expected something like this.

[Thomas] You did not tell us which distribution you are running. Not that it really matters, but each distribution has a slightly different way of handling console keymaps.

Oh yes, sorry. I'm running Slackware 9.1

[Thomas] You should ensure, regardless that:

/etc/console/bootmap.gz

is correct, but I suspect it is since you were able to write us the e-mail.

If you're running debian, it is just a case of doing:

dpkg-reconfigure console-data

However, your errors are usually indicative that your keyboard mappings are off. The only thing I would have suggested is that you used loadkeys and dumpkeys, and if that doesn't work to define the keycodes yourself, via keymaps and setkeycodes( .

Strange, there is no directory called /etc/console here. I'm sure my keymap is good though. Other than the warning the keyboard works flawlessly and it doesn't happen when I use a standard keyboard. I prefer my wireless one though.

[K.-H] Well -- I've no idea how to change the keymap -- but if the keyboard is basically working and the only annoying thing is the flooded syslogs how about dropping these messages? As what kind of syslog messages are they logged? kernel? info level or higher? The old syslogd has restricted options to accept or dump messages of a particular type (not content filter). I know that SuSE 9.x offered a new improves syslogd as an alternative -- so that might even be able to do some fancy filtering on the message content (and dump your keycode warning). Won't help for the boot-log but /var/log/messages won't be floded anymore.

To read the boot log /var/log/boot.msg without the garbage you can run grep with negative filter like:

grep -v "your keycode" /var/log/boot.msg | less

The keyboard works but I don't like my log being made so huge by all that junk.

I went to look at the kernel messages with dmesg today, but surprise! All that I got was line after line of this:

keyboard: unknown scancode e0 64

dmesg and /var/log/messages are just about useless, flooded with that. It's the same scancode every time too.

[Ben] I just had a similar problem, although it wasn't a flood as it is for you; perhaps 10 of these messages every hour. Before I could get around to fixing it, I upgraded my kernel from 2.6.3 to 2.6.5 - and the problem went away. So, even though I can't take credit for finding the solution (or even the exact problem), there it is.

The "scan codes", as far as I could tell, were being generated by some kernel driver seeing a signal from a piece of hardware with which it wasn't completely familiar and spitting out the unknown signal as a "scan code". In my case, I'm pretty sure that it was the new Synaptics touchpad - which definitely required a new driver.

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