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From: Lowell Gilbert <freebsd-questions-local@be-well.ilk.org>
To: Miguel Barbosa =?iso-8859-1?Q?Gon=E7alves?= <m@mbg.pt>
Subject: Re: Disable FIFO on UART
References: <CAEdntmtta6LQ3U62sod8vGggTT5f1mqoWE0cf0wma=MCs-uvNA@mail.gmail.com>
Date: Mon, 06 May 2013 11:21:05 -0400
In-Reply-To: <CAEdntmtta6LQ3U62sod8vGggTT5f1mqoWE0cf0wma=MCs-uvNA@mail.gmail.com>
 ("Miguel Barbosa =?iso-8859-1?Q?Gon=E7alves=22's?= message of "Sun, 5 May
 2013 12:59:17 +0100")
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Miguel Barbosa Gon=E7alves <m@mbg.pt> writes:

> Back in FreeBSD 7 there was a flag to disable the FIFO on the sio
[...]
> Now with FreeBSD 8 which uses the UART device driver there's no option fo=
r that.
>
> I am looking to reduce the jitter I am getting on the serial port when
> connecting a GPS to the server.
>
> Can anyone help?

It looks do-able, although the interface is a bit more abstract and
covers a wider variety of hardware. You would probably need to contact
whoever's working on that driver these days.