Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!sun-barr!cs.utexas.edu!uunet!pyrdc!gmu90x!gmuvax2!rauletta
From: rauletta@gmuvax2.gmu.edu (R. J. Auletta)
Newsgroups: comp.unix.ultrix
Subject: Re: ULTRIX problems, problems and problems
Summary: Modem Problems/Fifo Overflow (A likely fix.)
Message-ID: <2121@gmuvax2.gmu.edu>
Date: 1 Sep 90 15:12:14 GMT
References: <2039@gmuvax2.gmu.edu> <1990Aug30.131419.1831@dsuvax.uucp> <JOSEVELA.90Aug31232154@mtecv2.mty.itesm.mx>
Reply-To: rauletta@gmuvax2.UUCP (R. J. Auletta)
Distribution: na
Organization: George Mason Univ. Fairfax, Va.
Lines: 35

In article <JOSEVELA.90Aug31232154@mtecv2.mty.itesm.mx> josevela@mtecv2.mty.itesm.mx (Jose Angel Vela Avila) writes:
>>>>>> On 30 Aug 90 13:14:19 GMT, ghelmer@dsuvax.uucp (Guy Helmer) said:
>
>> In <2039@gmuvax2.gmu.edu> rauletta@gmuvax2.gmu.edu (R. J. Auletta) writes:
>
>>>the following errors are reported on the console and by uerf 
>>>occasionally after a dialin session is terminated.
>
>>>MESSAGE                                 dhu1, line4: recv. fifo overflow
>
>> We've had a couple of different 2400 baud modems on our MicroVAX,
>> and with both the machine would crank out the same errors
>> ("dhu0, line0: recv. fifo overflow").
>
>We have a problem like yours, we have a VAX 6310 running Ultrix 3.0, and if we

My original posting was in error. I thought I had set the configuration
for the Hayes modems such that it would not echo commands (ATE0)
but I had in fact not (ATE1), though I remember quite clearly doing
so. I have every reason to believe this was the problem.
(I thought I had already fixed it, so when it happen again....)

So now the modem is completely quiet waiting for a dial-in, with
tip setting it so it generates the necessary responses.

I am still curious though about the meaning of the fifo error, why
it is so important, and why some errors messages (from the kernel?)
are not buffered to the console (polled character I/O?).
This problem use to crop up with NFS errors. For the 5 seconds it
would take to print the error out at 30cps on a decwriter
the kernel would hold the processor, then give you about a second
to "do something" before the next error.


--R J Auletta