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From: Matt Schulte <matts@commtech-fastcom.com>
Date: Tue, 16 Nov 2010 10:13:22 -0600
Message-ID: <AANLkTi=grehSnfWzCDtSXXmNb=-NAwbHHJ_P1XPyOuw8@mail.gmail.com>
Subject: Re: [PATCH] Documentation about RS485 serial communications
To: Pavel Machek <pavel@ucw.cz>
Cc: Claudio Scordino <claudio@evidence.eu.com>, Greg KH <gregkh@suse.de>,
        Nicolas Ferre <nicolas.ferre@atmel.com>, linux-serial@vger.kernel.org,
        Grant Edwards <grant.b.edwards@gmail.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Alan Cox <alan@lxorguk.ukuu.org.uk>
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On Tue, Nov 16, 2010 at 8:30 AM, Pavel Machek <pavel@ucw.cz> wrote:
> Hi!
>
>> Documentation about RS485 serial communications
>
> I have seen hardware (kontron pmc-6l) that was capable of switching
> between RS232, RS485 and one other standard by software.
>
> Is such hw common? If so, should we have standard interface?

In my opinion this type of card is not that common.  Generally
speaking the achievable baud rates for this type of multi-protocol
card are very limited because of limitations of the transceiver chips.
 It seems that most of the time people would rather have a faster
serial port than one that does several different voltages.

Matt Schulte