3B1 only echoes one character for every several typed

Prentiss Riddle riddle at woton.UUCP
Thu Jun 30 01:37:13 AEST 1988


Last week I posted this question:

>> Description: The 3B1 only echoes one character for every several typed
>> at the console.  Apparently most of the characters typed are in fact
>> received, but only a few are echoed.  A reboot fixes the problem. 
>> 
>> This happens to us intermittently on several of our machines (running
>> 3.5, if it makes a difference).  Is this a known problem?  Can anyone
>> offer an explanation or a fix? 

Here are excerpts from the replies.  (Thanks, everybody.)
----------------------------------------------------------------------
Date: 23 Jun 88 14:15:37 PDT (Thu)
From: cs.utexas.edu!ut-sally!ames!ucsd!elgar!ford (Mike "Ford" Ditto)

I have seen this happen when the 3b1 is being bombarded by rs-232
input (such as from a babbling getty and/or a smart modem with
command-echo turned on).  Try disconnecting whatever is plugged into
the serial port(s) and see if the problem goes away.

					-=] Ford [=-
----------------------------------------------------------------------
Date: Fri, 24 Jun 88 09:15:14 EDT
From: cs.utexas.edu!tut.cis.ohio-state.edu!ihnp4!ihlpe!dopey

The one thing I've seen which causes this is when background processes
are running and reading from tty.  Might be worth checking - could be a
simple problem. 

The difficulty is getting the machine to do a "ps" when it only reads
every n'th character. 

I've had this problem particularly from remote logins where I'm using
UA, hang up, and come back; both UA and getty end up running.  Ugh. 

James C Blasius   att!ihlpe!dopey
----------------------------------------------------------------------
Date: 23 Jun 88 06:45:15 CDT (Thu)
From: cs.utexas.edu!marque.mu.edu!roger (Roger Abrahams)

I had this problem when I attempted to communicate with another machine, a
real Convergent Miniframe.  After a uucp, the machine would behave as you
described.  I attributed this to some failure in the uucp communication that
left the on-board modem in a weird state.

The cure was to install the "uucicio" form the 3.51a "fixdisk".  Note that
this is the ONLY thing I installed.  I did not install the new "Unix" kernal
from the fixdisk...
						- Roger
----------------------------------------------------------------------
Date: Fri, 24 Jun 88 12:53:23 EDT
From: cs.utexas.edu!tut.cis.ohio-state.edu!osu-cis!att!mtune!sfsup!usenet

I'm interested in a summary of what you find out.  I've had the problem
happen, particularly when somehow the system seems to get hosed and
have another shell or login process running on the same window or
terminal (on a remote terminal).  Not sure how it happens.  Rebooting
is needed for the login case; killing the shell works in the other
case.  Also I've had characters echoed but not given to the process -
this latter only happens in mailx.  Here the only solution is to
printout the message before sending it or to input the message using a
screen editor (I use emacs).  mailx seems to put the terminal into some
strange modes, and the editor counteracts them. 

Dave Kallman, AT&T, attunix!dkk, (201)658-2238
----------------------------------------------------------------------
-- Prentiss Riddle ("Aprendiz de todo, maestro de nada.")
-- Opinions expressed are not necessarily those of my employer.
-- riddle%woton.uucp at cs.utexas.edu  uunet!ut-sally!cs.utexas.edu!woton!riddle



More information about the Unix-pc.general mailing list