Subject: Re: slow network, serial ports, or firewall?
To: None <firstname.lastname@example.org, port-pc532@NetBSD.ORG>
From: Phil Budne <email@example.com>
Date: 08/05/1996 16:31:27
Subject: slow network, serial ports, or firewall?
Date: Thu, 01 Aug 1996 19:54:33 -0500
From: Jon Buller <firstname.lastname@example.org>
Could it be a driver interaction between the two serial ports
on the same chip?
It's possible, although it's also possible that using channels on the
same chip could be beneficial (fewer interrupt events to process).
It should be easy enough to try it both ways.
You could also try my serial driver. The latest go-round uses
"hardware" soft interrupts (twiddles the ICU to generate the softint
for the scn driver, and avoids waiting until the next spl to level
zero) to reduce softint latency. The character reception interrupt is
driven by the RxRDY lines, and the ISR runs without masking any
interrupts, and then triggers a softint. The softint code then runs
and drains the ring buffers from each port into the line discipline
input routines. The driver also supports h/w flow control in the
chip, and allows you to set a port to 57600bps.
I also added an ifdef for SCNDEF_CFLAG which you can define to your
favorite combination of flags (defaults to TTYDEF_CFLAGS if not
The driver is available from