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Date: Sat, 15 Nov 1997 15:23:09 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199711150423.PAA28278@godzilla.zeta.org.au>
To: bde@zeta.org.au, mouth@ibm.net
Subject: Re: Status of 650 UART support
Cc: hackers@FreeBSD.ORG
Sender: owner-freebsd-hackers@FreeBSD.ORG
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>>>Edge triggered interrupts are not a factor.
>>
>>Yes they are.
>
>In what way?

They force the interrupt handler to check all possible sources of the
interrupt, although 90-99% of the times there will only be one interrupt
source so returning after handling only one is best if checking the
others is expensive (as it is for separate ISA devices).

Bruce