> I'm working on a StyleWriter printer driver for NetBSD-mac68k [...]

> What I'd like to figure out is:  what could the printer possibly be
> doing to the serial port that would bring down the system?  Does
> 'stty -echo' mean that absolutely nothing will be echoed, or could
> certain incoming binary data cause the printer and the serial driver
> to start chatting at full speed?  (I suspect that could cause the
> symptoms I see...)

"stty -echo" is not a global disable.  In particular, if ECHONL is set,
some things will be echoed even if ECHO is not set.  Depending on
whether your kernel has the fix for PR 1922, it will echo either
newlines or everything but newlines.  (Check /sys/kern/tty.c around
line 1768; a line "(!ISSET(tp->t_lflag, ECHONL) || c == '\n')) ||" is
the buggy version - the == should be !=.)

Of course, if ECHONL isn't set, this can't be what's wrong.

> This is with a -current kernel supped a couple of weeks ago.

Hm, I don't recall just when that fix got committed, but I _think_ you
should have it; the PR is dated Jan 10, and I think the fix went in
pretty promptly.  Unfortunately query-pr doesn't seem to find closed
PRs even if you ask for them by number - or at least I haven't managed
to persuade it to - so I can't ask for it and look at the audit trail
to see when it was closed....

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu