Subject: Re: Serial changes 1.1-current
To: None <perry@piermont.com>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: port-i386
Date: 05/03/1996 21:28:34
On Fri, 03 May 1996 21:01:41 -0400 
 "Perry E. Metzger" <perry@piermont.com> wrote:

 > Sun 3/60s have far superior serial hardware to PC serial hardware. PC
 > serial controllers are nearly the worst imaginable. Getting the things
 > to operate well is very hard -- the Linux folks had to alter the
 > entire tty driver to do it.

*cough* *spew coffee*

The Zilog 8530 *SUCKS*  I'd take a 16550 over it *ANY* day!  :-)

Now, 16550 on an ISA card may very well chomp rocks, but that's probably 
due to the i386's (hardware) lame-o interrupt system :-)

The 16550-alike on my hp380 (the one with the FIFO ... there's also a 
16550-alike for the hp300s without a FIFO, found on earlier models) can 
do 38.4k without much of a problem at all.

There are other things that can be done to the NetBSD kernel to improve 
serial performance as a whole, and they've been discussed on tech-kern 
before.

----save the ancient forests - http://www.bayarea.net/~thorpej/forest/----
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
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