From owner-freebsd-hackers  Fri Aug 25 10:46:41 1995
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To: terry@cs.weber.edu (Terry Lambert)
From: dennis@et.htp.com (dennis)
Subject: Re: ISDN Anyone?
Cc: hackers@freebsd.org
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>> > There is actually a lot more promise in a 16550 or 16650 at 460800 bps.
>> > You only get 1/16th or 1/32th the number of interrupts.
>> 
>> Hmmm.  I find that the serial interrupt overhead is pretty intense at 115.2
>> even with a 16550.  You know some secret for doing this I don't?
>
>That's because it's being done wrong.
>
>You take the interrupt and poll like hell in the service routine to handle
>higher data rates.  You can do 115k on a non-FIFO'ed UART using this
>technique.
>
One interrupt per packet with a smart sync card.

db