[comp.unix.microport] Internal serial ports under AT&T 3.2

dave@pmafire.UUCP (Dave Remien) (02/26/89)

Remember all the flaming about internal serial ports (COM1 and COM2)
being unable to handle significant (i.e., over 2400) baud rates under
UNIX (Microport took most of the heat), where SCO had no problems? I've
been working on a 20Mhz AT&T 6386WGE (WGE!?) tower, and under AT&T V/386
3.2, the internal port can't reliably handle 1200 baud, on an unloaded
system.  An AT&T IPC-802 intelligent card can handle the serial I/O
without problems, but plugging an HP Paintjet into one of it's two
parallel ports causes the Wangtek 125Mb tape drive to fail, and then the
serial ports act weirdly (sometimes you can talk to 'em, sometimes you
can't).  Plugging the Paintjet into the internal parallel port,
everything works fine.  Thought I was going bananas, until I discovered
that. 




-- 
Dave Remien - WINCO Computer Engineering Group (only somewhat confused, now)
Work - 208-526-3523 Home - 208-524-1906 UUCP Path: ...!bigtex!pmafire!dave 
"How can you be in two places at once, when you're not anywhere at all..."

neighorn@qiclab.UUCP (Steve Neighorn) (02/27/89)

In article <595@pmafire.UUCP> dave@pmafire.UUCP (Dave Remien) writes:
>Remember all the flaming about internal serial ports (COM1 and COM2)
>being unable to handle significant (i.e., over 2400) baud rates under
>UNIX (Microport took most of the heat), where SCO had no problems? I've
>been working on a 20Mhz AT&T 6386WGE (WGE!?) tower, and under AT&T V/386
>3.2, the internal port can't reliably handle 1200 baud, on an unloaded
>system.  An AT&T IPC-802 intelligent card can handle the serial I/O
>without problems, but plugging an HP Paintjet into one of it's two
>parallel ports causes the Wangtek 125Mb tape drive to fail, and then the
>serial ports act weirdly (sometimes you can talk to 'em, sometimes you
>can't).  Plugging the Paintjet into the internal parallel port,
>everything works fine.  Thought I was going bananas, until I discovered
>that. 

Please no flames if I am entirely off-base, but I have encountered problems
relating to failing devices on machines I was asked to look at because of
conflicting interrupts. For example, the normal LPT1 interrupt is 7, and
the normal LPT2 interrupt is 5. Int 5 is also normally used by the Bell
Tech tape drive interface card, so there goes your 2nd printer port. Also,
I have seen network cards installed on Int 3 (Normally used for COM2) cause
problems with serial communications. In addition, problems can arise from
conflicting base addresses, ie Ethernet card and Tape card both strapped 
for 0x300H base address. You might try checking your interface cards and
of course the appropriate space.c files in your kernel config directory.

I am puzzled by all the serial port problems I read about in this group.
My 80386 Unix machine (catlabs) is connected directly with qiclab. I use
tip between the two machines all the time. qiclab also polls catlabs hourly
for the purpose of archiving certain newsgroups. All this is done at 9600
baud, and often at the same time a mouse is being used on catlabs. I
believe the problems exist, simply by the amount of traffic "serial woes"
seem to generate. I guess the problem is in some part installation 
specific.

If my ideas on conflicting interrupts and/or base addresses is old and
solved news to you, my apologies. I thought I would throw some of my
experiences with mis-behavin' machines into the ring.
-- 
Steven C. Neighorn           !tektronix!{psu-cs,nosun,ogccse}!qiclab!neighorn
Sun Microsystems, Inc.      "Where we DESIGN the Star Fighters that defend the
9900 SW Greenburg Road #240     frontier against Xur and the Ko-dan Armada"
Portland, Oregon 97223          work: (503) 684-9001 / home: (503) 645-7015

mark@intek01.UUCP (Mark McWiggins) (02/28/89)

Gosh, this makes me feel better.  Well, not better, but at least not so
alone ... :)

I have Enix 3.2 and AT&T 3.2.  I first installed Enix.  Had serial port
problems.  Couldn't run getty at all on the port; got a flickering DTR
light and "respawn is happening too rapidly; check this line in your
inittab."  Couldn't reliably dial out via uucp with my Telebit; sometimes 
it worked (usually just after a reboot), sometimes not.  Kermit mostly
worked fine, strangely enough, although I noticed that I couldn't change
line speeds without getting out of Kermit and back in.

We have an Everex tape drive, and Enix (distributed by Everex) comes with
a device driver for it.  I installed AT&T on a spare disk drive I have 
just to make sure I could transfer over the tape driver.  That worked fine.
I had a slight suspicion of hardware weirdness with my serial port, so
while I was at it tried running a getty on it and having someone dial in.
This worked fine.

So ... I backed up my data and installed AT&T on my big hard disk.  Running
uucico -x4 I get "lost line - error 0" and finally CALLER SCRIPT FAILED.
Kermit hangs when I do "set line /dev/tty00".

Can anybody recommend a NON-intelligent add-on serial port board that has
been shown to work with AT&T 3.2?  We just want to run mail/news, and other
access to the system will be via ethernet.

Thanks in advance for any help.  *sigh*
-- 

Mark McWiggins			UUCP:		uunet!intek01!mark
DISCLAIMER: I could be wrong.	INTERNET:	intek01!mark@uunet.uu.net
						(206) 455-9935

ebeser@wb3ffv.UUCP ( K3UHF) (03/04/89)

In article <396@intek01.UUCP>, mark@intek01.UUCP (Mark McWiggins) writes:
> 
> I have Enix 3.2 and AT&T 3.2.  I first installed Enix.  Had serial port
> problems.  Couldn't run getty at all on the port; got a flickering DTR
> light and "respawn is happening too rapidly; check this line in your
> inittab."  Couldn't reliably dial out via uucp with my Telebit; sometimes 
> it worked (usually just after a reboot), sometimes not.  Kermit mostly
> worked fine, strangely enough, although I noticed that I couldn't change
> line speeds without getting out of Kermit and back in.

I had the same problem with my serial port. The catch-22 was that getty
with a modem expected modem controls. The call to enix solved the problem.
I made a new node with the modem controls. It seems their drivers support
it. 

type:

mknod /dev/ttyM00 c 3 128

then respawn /usr/lib/uucp/uugetty ttyM00.

That will work fine.

> 
> So ... I backed up my data and installed AT&T on my big hard disk.  Running
> uucico -x4 I get "lost line - error 0" and finally CALLER SCRIPT FAILED.
> Kermit hangs when I do "set line /dev/tty00".
> 
I still haven't solved this problem. Anyone else?

mark@intek01.UUCP (Mark McWiggins) (03/06/89)

Bill Kennedy saves the day!  It turns out that there are subtle differences
in AT&T 3.1 UUCP, AT&T 3.2 UUCP, and Enix 3.2 UUCP, and that was what
tripped me.

Modem control was indeed the problem.  A friend running 3.1 sent me his
UUCP setup that worked without it; the setup sortof worked on Enix and
sortof worked a different way on AT&T 3.2.  Bleah!   I tried RTFMing
early on, but it seemed obscure on this point at best.

Mr. Kennedy also points out that Enix (and apparently Interactive as well)
needs DCD forced high (S53=0 on the Telebit), and that the tty permissions
have to be set correctly (666, or owned by UUCP).

Good luck to everyone else hacking his/her way through the RS232 jungle ... :)
-- 

Mark McWiggins			UUCP:		uunet!intek01!mark
DISCLAIMER: I could be wrong.	INTERNET:	intek01!mark@uunet.uu.net
						(206) 455-9935