Re: Sequence of zeros (0000...) appears without key pressed

Moe Trin schrieb:
On Sat, 27 Jan 2007, in the Usenet newsgroup comp.os.linux.hardware, in article
<epf5pl$g5$1@xxxxxxxxxxxxxxxxxxxxxxxxx>, Juergen wrote:

Allodoxaphobia, I tried another keyboard (from Dell, USB) and connected
it to the USB port only. My normal keyboard is a USB keyboard connected
to the PS/2 using an adapter.
The generation of zeros remains ...

So it's not likely to be the keyboard

Could it be that the mainboard might have a problem,

Yes. The keyboard connects to the computer using a five or six pin
connector, moving "data" as serial bits. On the motherboard, there is a
converter chip - originally a 8048 or 8049 microcontroller, later included
in the "Super I/O" chip, later still moved into the South Bridge chip.
These are soldered to the motherboard, and are not easily repairable.

that I did something wrong in the keyboard settings

I don't think so - but you might use a keyboard sniffer to find out.
Under XFree86, there was an application called

[compton ~]$ whatis xev
xev (1x) - print contents of X events
[compton ~]$

but you may also have

[compton ~]$ whatis dumpkeys showkey
dumpkeys (1) - dump keyboard translation tables
showkey (1) - examine the codes sent by the keyboard
[compton ~]$

(Try 'apropos key' and see if there is another helpful program.) Each key
action (press and/or release) sends an 8 bit pattern over the serial link.
The shift key is just another key, so your string of zeros is something
simulating the press/release of the zero key. Note that the zero key on
the top of the keyboard sends a different code than the zero key that is
part of the numeric keypad. Note that you may need to be 'root' to run
showkey as it is reading hardware directly.

or I got some Trojan horse, root-kit, ...?

It would be a most unusual type of Trojan or root-kit. I'd suggest this is
also _highly_ unlikely.

That's good news!

Another thing to try would be to get out of X, (you're probably using a
GUI login, so try pressing the left 'ALT' and 'CTRL' and 'F2' keys together
to get to a text console - press the left 'ALT' and F7 or F9 key [depending
on how many mingettys are running] to return to X), and see if you have the
random zeros there as well. If yes, I'd suspect the South Bridge chip, but
if not, you've got something strange in your X setup.

Old guy

I did something like this: My system uses the grub boot-loader. So I
directly went to the command prompt of grub and waited quite a while. No
zeros! This afternoon, I found a solution to keyboard related problems
in the current X-server keyboard driver "kbd", see reply with subject

"Solved (?): Sequence of zeros (0000...) appears without key pressed"

in this thread for futher details. Hopefully, changing to the "keyboard"
driver solved my problems ...

This is very much in line with what you guessed. I will make use of the
tools you adviced if my problems come back again! I hope this solution
remains stable, otherwise it's probably really a mainboard problem.

Moe Trin, thanks for your very helpful comments and hints!


Yours, Juergen
.

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