[maemo-developers] Problem with three keys pressed

[From: Matan Ziv-Av]

On Sat, 5 May 2012, Paolo Iommarini wrote:

> I have a problem when three keys are pressed (I have the english keyboard).
> There are some keys combination that generates an additional key press.
> This seems a system bug.
>
> It can be reproduced in any textbox (like the contact search).
> If you press a+x+up arrow you'll see a "p".
>
> I noticed it while using the Game Gripper with the psx emulator: pressing 
> down+left+circle will end in a down+left+triangle+circle combination.
> I debugged the key-press-event and it is really getting a press event for the 
> key "p" (code 33).
>
> There are also other strange keys combination like
> a+x+return = ","
> a+x+. = "o."
>
> Can someone please test it and say if it's really a system bug?

This is a hardware issue. And there are more combinations revealing this 
issue. See for example here:

http://talk.maemo.org/archive/index.php/t-40806.html

I believe it is possible to recognize the fake key press/release events 
by analyzing the timing of those events, thus discarding these events 
and working around the hardware problem. But to my knowledge, noone has 
done it yet, and I do not expect anyone to actually do it.

-- 
Matan Ziv-Av.                         matan at svgalib.org