*BSD News Article 7709


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Newsgroups: comp.unix.bsd
Path: sserve!manuel.anu.edu.au!munnari.oz.au!spool.mu.edu!sol.ctr.columbia.edu!news.columbia.edu!cucbs.chem.columbia.edu!cucbs.chem.columbia.edu!russo
From: russo@cucbs.chem.columbia.edu (Thomas Russo)
Subject: [386BSD] /dev/com2 set to N,8,1 anyone? 
Message-ID: <RUSSO.92Nov14160143@cucbs.chem.columbia.edu>
Summary: I can't get slip to work at N,7,1, and can't get com2 to be N,8,1!
Keywords: SLIP problems com port 8 data bits frustration and so forth
Sender: russo@cucbs.chem.columbia.edu (Thomas Russo)
Organization: Center for Biomolecular Simulation, Department of Chemistry,
	Columbia University
Date: Sat, 14 Nov 1992 21:01:43 GMT
Lines: 81

Greetings all.  I have a problem getting my com port talking slip, to
a host which requires me to have com2 set at 38,400 baud, parity none,
8 data bits and 1 stop bit, with RTS/CTS handshaking.  I'm including a
lot of history and junk just in case it might provide a clue as to
what's wrong.  Please excuse the verbosity.  The Reader's Digest
version is this:

I am trying to set the com2 port to cs8, stty says it's set that way
but near as I can tell it's still communicating at cs7.  I'm at a loss
for what to do now.  Surely SOMEONE else runs slip at n,8,1?

Long-winded version:

I just got my 386 with 386bsd installed from the dist.fs floppy last
week.  I immediately tried running SLIP over a v.32bis/v.42bis,
38,400baud connection using the virgin 0.1 distribution, and of course
got the expected "silo overflows" and eventual hangs.  So I installed
the beta patchkit, rebuilt everything and tried again.  I also
installed the little patch posted here to enable RTS/CTS
handshaking.*Note below*

Now SLIP doesn't work at all.

It appears to be the case that the cisco terminal server that I'm
connecting to wants me to be talking at N,8,1, but near as I can tell
the com2 port (my 16550 is on com2, mouse on com1) will not set to cs8
no matter how hard I try and no matter what stty says it is set to.
Example:

stty cs8 -parenb -ixoff -ixon crtscts < /dev/com2
tip com2
<dial modem, start remote machine running slip>
~^Z
....start slip, ifconfig sl0, route add default, etc...

Then a ping of the remote machine gives lots of little blinking TD/RD
lights, but no received ICMP echos.

I should point out at this time that the same procedure DID work after
a fashion before I applied the beta patchkit, but of course only for a
few dozen Kbytes transferred.

Then I tried hooking up a plain old ascii terminal (actually a
Macintrash running zterm) to the com2 port (on which getty was NOT
running), set it to 38400,n,8,1 and did this:

stty cs8 -parenb crtscts -ixoff < /dev/com2
tip com2
<type lots of junk to see what comes up on the Macintrash screen>

What I get on the Mac is lots of garbage only mildly related to what
I'm typing into tip.  If I set the mac to n,7,1 I get what I type.

At this point I say "damn, the system's reset the cs8 flag" so I do:
~^Z
stty -a < /dev/com2

and GUESS WHAT?!?!  It says it is still set to cs8.

So what is going on?  Can anyone help?  Is this a known bug in the com
driver?  A feature?  A hardware problem?  Any suggestions for further
diagnostic procedures I should try to nail it down better?


-----* The RTS/CTS patch was posted here a few weeks ago by
andrew@werple.apana.org.au and amounts to commenting some stuff on
line 148, uncommenting other stuff on 489 and fixing what appears to
be a typo on line 403 of com.c (t_flags instead of t_cflag).  If
there's reason to suspect that this is causing my woes I'd love to
hear it.  But it seems unlikely to me, given the nature of the mods.
Maybe tonight when I get home I'll try booting the pl58 w/o
handshaking kernel I saved, to see if I can get cs8, if so, I'll beg
forgiveness for going off half-cocked here.  Of course then I have
another problem, 'coz I NEED handshaking...



-- 
Thomas Russo			russo@nile.chem.columbia.edu
Department of Chemistry and Center for Biomolecular Simulation
Columbia University