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Date: Thu, 06 Feb 1997 18:07:16 -0800
From: Julian Elischer <julian@whistle.com>
Organization: Whistle Communications
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To: Paul Traina <pst@jnx.com>
CC: Bruce Evans <bde@zeta.org.au>, hackers@freebsd.org, bde@freebsd.org
Subject: Re: serial ports at 230k
References: <199702062052.MAA00639@base.jnx.com>
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Paul Traina wrote:
> 
> Good guess, but I'm actually trying out a 3COM ISDN TA that runs at 230k.
> 
>   From: Bruce Evans <bde@zeta.org.au>
>   Subject: Re: serial ports at 230k
>   >Does anyone have any experience with running 16550A's at 230kbps under FreeB
> >>SD?
>   >Yes, I know, the driver doesn't support it currently, but has anyone played?
> 
>   Not me.  I checked the PC16550D specs recently.  The maximum speed is
>   1.5Mbps like I remembered.
> 
>   If you only care about remote gdb throughput to an sio port on a
>   FreeBSD host, note that the protocol is non-streaming so it is limited
>   to 1 packet per clock tick (30Kbps effective throughput at best) by the
>   host's pseudo-DMA timeout routine.
> 
>   Bruce
exactly why I was looking at it
(3COM impact)