Subject: Re: High serial port (output) speeds
To: None <port-sparc@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: port-sparc
Date: 10/23/1999 01:00:55
> The main advantage you get from deliberately using X16 mode is that
> the input logic can use the extra ticks to clean up an input signal
> by taking multiple samples and integrating them -- [some chips do
> this], but I no longer recall offhand if the 8530 did it too.

I've also seen it said that it allows the chip to time its sample to
fall more precisely in the middle of the bit time.  Personally I find
this latter possibility less plausible, as by trivially rearranging the
division counter chain you can get that benefit - or something very
close to it - even at X1....

In any case, nobody disagrees that there *is* a benefit to using X16.
That's why my patch does so whenever it's possible to do so and still
achieve the requested baudrate. :-)

					der Mouse

			       mouse@rodents.montreal.qc.ca
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