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From: Barry Lustig <barry@Lustig.COM>
Date: Thu,  6 Feb 97 14:55:53 -0800
To: Joe Greco <jgreco@solaria.sol.net>
Subject: Re: serial ports at 230k
cc: pst@jnx.com (Paul Traina), hackers@freebsd.org
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>  > Does anyone have any experience with running 16550A's at 230kbps under
>  FreeBSD?
> Yes, I know, the driver doesn't support it currently, but has
>  anyone played?
>  
>  Yes.  Take a standard serial card and replace the 1.8432MHz crystal with
>  a 3.6864 MHz crystal..  ;-)  Your "115200" speed will magically run at
>  230.4Kbps.
>  
>  I did it a long time ago, and if you're not one for soldering, I may have
>  a pair of souped up cards if you're interested in buyin' em...  or you can
>  go get the Hayes ESP serial cards.
>  

  I know that Zyxel (www.zyxel.com) sells a 2 serial 1 parallel add-on board (16550) with the clock selectable via jumper.  It can do 1X, 2X, or 4X on the clock.  Their ISDN TAs run the DTE at up to 460800, so they needed a solution.


barry