From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dirk Behme <dirk.behme@googlemail.com>
Subject: Re: Noise causes gpio interrupt
Date: Fri, 26 Jan 2007 15:15:22 +0100
Message-ID: <45BA0CFA.5010409@googlemail.com>
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To: Arnold <abo_gwapo@yahoo.com>
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Arnold wrote:
> ... However when the interupt comes from a
> device and the transition of rise to fall is 20ns it
> could not detect that an interrupt occured. I also
> tried to increase the transition to 20ms and it was
> able to detect the interrupt. ...

Maybe http://www.ti.com/litv/pdf/spru767a, section 1.6 or 
page 28, can help:

"Because of the sample operation with the functional clock, 
the minimum pulse
width on the input GPIO to trigger a synchronous interrupt 
request is two times
the functional clock period. This minimum pulse width must 
be met before and
after any expected level transition detection."

Best regards

Dirk