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Date:      Thu, 23 Feb 2006 13:42:39 -0800
From:      Maksim Yevmenkin <>
To:        Norbert Koch <>
Subject:   Re: does ukbd delay break scan codes?
Message-ID:  <>
In-Reply-To: <000001c6379d$63036d80$4801a8c0@ws-ew-3.demig.intra>
References:  <000001c6379d$63036d80$4801a8c0@ws-ew-3.demig.intra>

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> I still do not know where it comes from,
> but what I found so far is,
> that the usb keyboard (or ukbd driver)
> seems to delay the break codes for
> keys with prefix E0 (which may or may not
> have anything to do with my problem).
> E.g., I press Keypad-Enter and see
>   E0 1C E0
>         ^prefix
>      ^make code
>   ^prefix
> and nothing else. As soon as I press
> e.g. Enter (any key works) I see
>   9C 1C 9C
>         ^break code
>      ^make code
>   ^delayed break code.
> Does anyone have an idea where that
> may come from?

i see this to on week old -current. if ukbd(4) delays break code then 
this might explain state synchronization problem with kbdmux(4). i guess 
we should start digging into ukbd(4), starting with ukbd_interrupt() to 
see why this happening.

> Could it be a possible bug in ukbd's
> conversion code?

could be

> (BTW: I compared ukbd.c of RELENG-4
>  against RELENG-6. There are no
>  significant differences)

have you tried to look at other bsd's (i.e. netbsd for example)?

> My usb keyboard is a Cherry RS6000.

i do not think this has anything to do with the keyboard. i have 
ps/2-to-usb converter and use ps/2 keyboard with it, and, it has exactly 
the same problem.


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