[comp.dcom.modems] Need tty000 modem help

jbm@uncle.UUCP (John B. Milton) (11/12/88)

In article <4242@pitt.UUCP> anthony@pitt.UUCP (M. Anthony Kapolka 3) writes:
[describes modem setup]
>When I set it up (via /etc/inittab) with a getty, everything seems fine.
>When someone calls in, however, the modem picks up the phone and then
>promptly hangs up on the caller.
>
>If the modem receives a call without being connected to tty000 (ie the
>serial cable unplugged) it answers just fine.  If I then plug in the
>cable (with a getty sitting on the port) everything then works.
>(Gosh, maybe all I need is a trained monkey!)
When init spawns the getty, it hangs on opening the line until it gets CD
from the modem. The getty's open then succeeds and the getty wakes up. If the
cable is flaky or the CD line is floating, or something else causes CD to jump
or go away, the getty gets a SIGHUP and the getty dies. One way around these
problems is to create another set of /etc/gettydefs lines:
remove HUPCL and add CLOCAL. This is getting ugly, but whatever works. You 
may need to check /etc/profile to make sure the line doesn't get dropped by
a stty there.

[describes cable fudging]
>Any help would be appreciated... I don't have a break out box and this
>has just gotten too strange for me.  Surely someone else has had this 
>problem.
With one of those cheapy 5 LED jobs, you can diagnose 90% of all problems.
These are also good at reflecting signal strength in the brightness of the LED.
Like UNIX, the simplest tools are the most valuable.

[describes OS version]

>Also, does anybody out there have an auto-bauding getty working?

I have a very modified modem-ctl (was posted to the net) called prtty. It does
autobauding by letting a talkative modem TELL it what the speed is:

CONNECT
CONNECT 1200
CONNECT 2400

It then exec()s a "getty -h line speed". I have had this program out on beta
test for a while, with only minor complaints. I want to re-write it to be 
state driven, but I should post it as is first since I've got so many irons in
the fire as it is.

John
-- 
John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu
(614) h:294-4823, w:764-4272;  MS-DOS is a beautiful flower that smells bad!

gil@limbic.UUCP (Gil Kloepfer Jr.) (11/16/88)

In article <4242@pitt.UUCP> anthony@pitt.UUCP (M. Anthony Kapolka 3) writes:
[describes modem setup]
>When I set it up (via /etc/inittab) with a getty, everything seems fine.
>When someone calls in, however, the modem picks up the phone and then
>promptly hangs up on the caller.

[John Milton gives one explanation]

Another reason why this can happen is that when a Hayes compatible modem
is in verbose mode, and a caller calls in, the CONNECT xxx message is
sent to the 3B1 and is subsequently echoed back to the modem.  If this
happens fast enough on some modems (ie. the "C" in "CONNECT" gets sent back
to the modem before the whole CONNECT xxx message is displayed), the modem
will think you are aborting the call.  I wouldn't have even mentioned this
except that it happened to me!

No flames on config, etc. please.  This was one of many ways I tried to get
this particular modem to work right on the 3B1.  After hours of fighting with
the modem, I sold it.

One more question -- Has anyone (successfully) gotten a cheap 300/1200/2400
baud modem to work right with the 3B1.  I am using a Microcom (borrowed) which
has a braindamaged autobaud system.  I would like to hear what needs to be
done to set it up, and what the price is.  If I get a lot of personal
responses, I'll summarize.

--------
Gil Kloepfer, Jr.          U-Net: {decuac,boulder,talcott,sbcs}!icus!limbic!gil
ICUS Software Systems      Voice: (516) 968-6860 [H]   (516) 746-2350 x219 [W]
P.O. Box 1                 Internet:  gil@icus.islp.ny.us
Islip Terrace, NY  11752   "Life's a ...  well, you know..."

jeff@tekcsc.MKT.TEK.COM (Jeff Beadles) (11/18/88)

In article <392@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes:
 In article <4242@pitt.UUCP> anthony@pitt.UUCP (M. Anthony Kapolka 3) writes:
 [describes modem setup]
 >When I set it up (via /etc/inittab) with a getty, everything seems fine.
 >When someone calls in, however, the modem picks up the phone and then
 >promptly hangs up on the caller.
 
 [John Milton gives one explanation]
 
 Another reason why this can happen is that when a Hayes compatible modem
 is in verbose mode, and a caller calls in, the CONNECT xxx message is
 sent to the 3B1 and is subsequently echoed back to the modem.  If this
 happens fast enough on some modems (ie. the "C" in "CONNECT" gets sent back
 to the modem before the whole CONNECT xxx message is displayed), the modem
 will think you are aborting the call.  I wouldn't have even mentioned this
 except that it happened to me!

Well, here's how I have worked around this.  First, set the modem so it
does not return result codes, nor echo.  (ATE0Q1)  This will allow it to
answer (dial-in) calls ok.  In your chat script for calling, use something
like this:   ATE1Q0 OK ATDTxxxxxx NNECT ...  
This will turn the echo on, so you can tell if it's connected or not.
Then, set the modem so it will reset on DTR toggle.  (For a 2400 hayes, I
believe that it's &D?  (not sure)  On a 'Blazer, it's ATS52=2

Hope this helps,

		-Jeff Beadles


-- 
Jeff Beadles  IDG Customer Support Center  Tektronix, Inc.
jeff@tekcsc.mkt.tek.com -or-               POB 1000
 ..!tektronix!tekcsc.mkt.tek.com!jeff      Wilsonville, OR. 97070 MS 63-171
Newsgroups: unix-pc.general,comp.dcom.modems
Subject: Re: Need tty000 modem help
Summary: 
Expires: 
References: <4242@pitt.UUCP> <417@uncle.UUCP> <392@limbic.UUCP>
Sender: 
Reply-To: jeff@tekcsc.UUCP (Jeff Beadles)
Followup-To: 
Distribution: na
Organization: Tektronix, Inc.  Wilsonville, Or.
Keywords: 

In article <392@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes:
 In article <4242@pitt.UUCP> anthony@pitt.UUCP (M. Anthony Kapolka 3) writes:
 [describes modem setup]
 >When I set it up (via /etc/inittab) with a getty, everything seems fine.
 >When someone calls in, however, the modem picks up the phone and then
 >promptly hangs up on the caller.
 
 [John Milton gives one explanation]
 
 Another reason why this can happen is that when a Hayes compatible modem
 is in verbose mode, and a caller calls in, the CONNECT xxx message is
 sent to the 3B1 and is subsequently echoed back to the modem.  If this
 happens fast enough on some modems (ie. the "C" in "CONNECT" gets sent back
 to the modem before the whole CONNECT xxx message is displayed), the modem
 will think you are aborting the call.  I wouldn't have even mentioned this
 except that it happened to me!

Well, here's how I have worked around this.  First, set the modem so it
does not return result codes, nor echo.  (ATE0Q1)  This will allow it to
answer (dial-in) calls ok.  In your chat script for calling, use something
like this:   ATE1Q0 OK ATDTxxxxxx NNECT ...  
This will turn the echo on, so you can tell if it's connected or not.
Then, set the modem so it will reset on DTR toggle.  (For a 2400 hayes, I
believe that it's &D?  (not sure)  On a 'Blazer, it's ATS52=2

Hope this helps,

		-Jeff Beadles


-- 
Jeff Beadles  IDG Customer Support Center  Tektronix, Inc.
jeff@tekcsc.mkt.tek.com -or-               POB 1000
 ..!tektronix!tekcsc.mkt.tek.com!jeff      Wilsonville, OR. 97070 MS 63-171

ebd@cup.portal.com (Elliot B Dierksen) (11/19/88)

I have a 2400 baud called a Smart One 2400X that works fine for in & out
traffic with autobaud. The way i did it is the modem is set to quiet mode
E0 Q1 normally. when i need to call out, i send the command to the modem
to turn the responces back on. when i release the modem (drop DTR), it
is set to reconfigure from NVRAM. It hiccups slightly with the Unix PC
ATE package though. ATE removes to lock file before it releases the port
so the modem never resets. then login starts trying to get OK onto my
system. if anyone has any comments on that... I'm all ears!!

Elliot Dierksen
ebd@cup.portal.com