Subject: Serial port overruns
To: port-mac68k <port-mac68k@NetBSD.ORG>
From: Bill Studenmund <wrstuden@loki.stanford.edu>
List: port-mac68k
Date: 12/06/1995 10:27:56
Howdy!

I'm trying to get an idea about the fifo overruns everyone's
been seeing with the latest serial code. Mainly, I'm trying to
figure out if the overruns are real or not.

So what kind of overruns are they? fifo overruns are chip-based
and ring overruns are software based. Also, what port are they
on, and are you using that port?

zs0a is the modem port
zs0b is the printer port

The nomenclature is left over from the fact that the sun port, from
whom the core code originates.

I'm asking these questions as last night I realized that the ROM
adb code might be freaking out the serial ports. I was editing a
file in vi in single-user mode, and got zs0b fifo overruns when I
pressed a key for an extended periond of time (longer than about
1/2 second). The wierd thing was that I didn't have anything happening
on the printer port at the time!

So I'm wondering how many of the people having fifo overruns while
ppp'ing are actually getting them on the port in use (remembering that
the modem is zs0a)?

Thanks!

Bill