keyboard problems

keyboard problems

[Thomas Graichen]

i have a little keyboard problem on my blueberry imac with the
standard usb keyboard: whenever i type something very quickly
followed by space the typed in will be repeated before the
space (best example: i want to type "cd " and get "cdcd ")
- this gets a bit annoying - does anybody have the same
problem (or even a fix for it) ? - is it more a soft-
wareproblem (i hope :-) or maybe a hardwareproblem ?
(i had it on all kernels from 2.2.x to 2.4.0-testx)

a lot of thanks in advance

t

p.s.: it appears both on the console and under x - so it has
      to - if software - a problem in the kbd driver

--
thomas.graichen@innominate.de
technical director                                       innominate AG
clustering & security                                networking people
tel: +49.30.308806-13 fax: -77 web: http://innominate.de pgp: /pgp/tgr

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keyboard problems

[Thomas Graichen]

looks like this one got lost too - so here it is again ...

i have a little keyboard problem on my blueberry imac with the
standard usb keyboard: whenever i type something very quickly
followed by space the typed in will be repeated before the
space (best example: i want to type "cd " and get "cdcd ")
- this gets a bit annoying - does anybody have the same
problem (or even a fix for it) ? - is it more a soft-
wareproblem (i hope :-) or maybe a hardwareproblem ?
(i had it on all kernels from 2.2.x to 2.4.0-testx)

a lot of thanks in advance

t

p.s.: it appears both on the console and under x - so it has
      to - if software - a problem in the kbd driver

--
thomas.graichen@innominate.de
technical director                                       innominate AG
clustering & security                                networking people
tel: +49.30.308806-13 fax: -77 web: http://innominate.de pgp: /pgp/tgr

** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/

Re: keyboard problems

[Nelson Abramson]

Thomas Graichen wrote:

> i have a little keyboard problem on my blueberry imac with the
> standard usb keyboard: whenever i type something very quickly
> followed by space the typed in will be repeated before the
> space (best example: i want to type "cd " and get "cdcd ")
> - this gets a bit annoying - does anybody have the same
> problem (or even a fix for it) ? - is it more a soft-
> wareproblem (i hope :-) or maybe a hardwareproblem ?
> (i had it on all kernels from 2.2.x to 2.4.0-testx)

This is a well known issue with the usb keyboard driver.  It was a a
relatively lengthy thread a few months ago with no (AFAIK) solution,
other than "will be fixed in the future".

It has to do with depressing three keys at a time.  It takes a little
getting used to, but now, except for the occasional moment of serious
energy, I no longer strike three simultaneous keys on my Sawtooth.

HTH
--Nelson Abramson


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Re: keyboard problems

[David A. Gatwood]

On 1 Aug 2000, Thomas Graichen wrote:

> i have a little keyboard problem on my blueberry imac with the
> standard usb keyboard: whenever i type something very quickly
> followed by space the typed in will be repeated before the
> space (best example: i want to type "cd " and get "cdcd ")
> - this gets a bit annoying - does anybody have the same
> problem (or even a fix for it) ? - is it more a soft-
> wareproblem (i hope :-) or maybe a hardwareproblem ?
> (i had it on all kernels from 2.2.x to 2.4.0-testx)

I believe I've experienced this as well.  As I recall, it occurs when two
non-modifier keys are pressed nearly simultaneously.  I suspect the issue
is that the driver is seeing a key up event and passing it on, and then at
a higher level, the kernel is getting confused because it gets two key
downs followed by two key ups, and proceeds to turn them all into bytes at
the tty level or something similar, instead of ignoring the key up events.

Probably the easiest fix would be to modify the driver to send a key up
event when a second key is pressed, even if the first key hasn't been
pressed, then to ignore the very next key up event for that first key....
Just a thought.  Of course, it's critical that such a change exclude the
modifier keys, so....  Not sure how easy that would end up being.

I'm not sure how to implement that sort of change beyond a conceptual
view, though, as I haven't really looked at Linux's USB drivers much.


Later,
David

---------------------------------------------------------------------
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It seems secure at first glance.
Then you read your mail.


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Re: USB keyboard problems - cdcd

[Hollis Blanchard]

Thomas Graichen wrote:
>
> i have a little keyboard problem on my blueberry imac with the
> standard usb keyboard: whenever i type something very quickly
> followed by space the typed in will be repeated before the
> space (best example: i want to type "cd " and get "cdcd ")
> - this gets a bit annoying - does anybody have the same
> problem (or even a fix for it) ? - is it more a soft-
> wareproblem (i hope :-) or maybe a hardwareproblem ?
> (i had it on all kernels from 2.2.x to 2.4.0-testx)

This is well-known (at least for people with USB keyboards). Interestingly,
it *only* seems to happen with the old Apple USB mini keyboard (the fullsize
is too new; haven't heard anything about it).

The problem only seems to happen when some (not all) groups of three keys
are hit too quickly. It could be because this keyboard physically allows you
to press more keys simultaneously, or it could be driver-related (or both).

The only solution for now seems to be type "cd " one key a time.

-Hollis

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Re: keyboard problems

[Paul Mackerras]

Thomas Graichen writes:
>
> i have a little keyboard problem on my blueberry imac with the
> standard usb keyboard: whenever i type something very quickly
> followed by space the typed in will be repeated before the
> space (best example: i want to type "cd " and get "cdcd ")
> - this gets a bit annoying - does anybody have the same
> problem (or even a fix for it) ? - is it more a soft-
> wareproblem (i hope :-) or maybe a hardwareproblem ?
> (i had it on all kernels from 2.2.x to 2.4.0-testx)

It's simply a bug in the USB keyboard driver.  It just means that the
driver isn't coping with the "overflow" code that the keyboard sends
when it has too many keys depressed at once.

--
Paul Mackerras, Senior Open Source Researcher, Linuxcare, Inc.
+61 2 6262 8990 tel, +61 2 6262 8991 fax
paulus@linuxcare.com.au, http://www.linuxcare.com.au/
Linuxcare.  Support for the revolution.

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Re: keyboard problems

[Thomas Graichen]

Paul Mackerras <paulus@linuxcare.com.au> wrote:

> Thomas Graichen writes:
>>
>> i have a little keyboard problem on my blueberry imac with the
>> standard usb keyboard: whenever i type something very quickly
>> followed by space the typed in will be repeated before the
>> space (best example: i want to type "cd " and get "cdcd ")
>> - this gets a bit annoying - does anybody have the same
>> problem (or even a fix for it) ? - is it more a soft-
>> wareproblem (i hope :-) or maybe a hardwareproblem ?
>> (i had it on all kernels from 2.2.x to 2.4.0-testx)

> It's simply a bug in the USB keyboard driver.  It just means that the
> driver isn't coping with the "overflow" code that the keyboard sends
> when it has too many keys depressed at once.

any chance of this getting fixed in the next time ? - any patch
around to try ? (because it's close to unuseable for me this
way :-)

t

--
thomas.graichen@innominate.de
Technical Director                                       innominate AG
Clustering & Security                                networking people
tel: +49.30.308806-13  fax: -77                   http://innominate.de

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