Thanks to all those who replied. That question has probably been answered
many many times, but I am new to the mailing list and I needed to set up a
modem.
Here are some responses/suggestions I have received:
================================================================================
FROM Chris:
(He saw that answer somewhere)
I've got a DEC 3000-300 running OSF/1 v1.3A, and a MultiTech MultiModemV32
modem. I've got ttyd0 configured successfully, and the modem functions as
it should, including it hanging up on logout. To accomplish this, I was
only successful with a Digital BC22E-25 cable (none of my "null modem"
cables did everything as this cable did, but I didn't try too hard to
reconfigure them, either). I found the BC22E-25 cable laying around, so
I grabbed it and tried it.
*** NOTE: THIS IS NOT THE SETUP FOR AN OUTGOING MODEM, JUST INCOMING. ***
*** I will start work on the outgoing modem configuration soon. ***
I have made the following modifications to my system:
to /etc/inittab, commented out one line and added the next:
#modem:23:respawn:/usr/lib/uucp/uugetty -r -t 30 ttyd0 9600 #UUCP
modem:23:respawn:/usr/sbin/getty ttyd0 M19200 vt100
^^|^^^
This means use the M19200 entry in /etc/gettydefs
to /etc/ttys, I verified ttyd0 line:
ttyd0 none none # modem line
to /etc/gettydefs, I added/modified the lines below (note the initial
login prompt (yes?) for the M19200 line - keeps folks guessing what kind of
system this is):
...
M19200# B19200 HUPCL CS8 # B19200 SANE IXANY TAB3 HUPCL #yes? #M19200
...
7bit.19200# B19200 HUPCL CS7 CLOCAL # B19200 SANE PARENB CS7 ISTRIP IXANY TAB3 C
LOCAL #login: #7bit.19200
7bit.M19200# B19200 HUPCL CS7 # B19200 SANE PARENB CS7 ISTRIP IXANY TAB3 HUPCL #
login: #7bit.M19200
I sent the following command to the modem to use the default settings, plus
answer on 3rd ring, use Xon/Xoff, let modem respond to Xon/Xoff and
pass them through, set normal mode modem control to Xon/Xoff,
and talk to the serial port at 19200bps:
first command sets it current, second command stores it in EEPROM.
# echo "AT&FS0=3&E5&E7&E11$SB19200&W" > /dev/ttyd0
# echo "AT&FS0=3&E5&E7&E11$SB19200&W0" > /dev/ttyd0
and restarted getty:
# kill -1 1
You should now be able to see the following process on your system:
root 13860 0.0 0.3 240K 88K d0 I + 13:37:14 0:00.05 /usr/sbin/getty
ttyd0 M19200 vt100
If the above process number then goes into a login: state without anyone having
dialed-in, something is wrong.
I also verified that /dev/ttyd0 is set as follows:
# file /dev/ttyd0
/dev/ttyd0: character special (24/2) VS_SLU #0 terminal #2
modem_control on
^^ This is most important.
The modem should answer as expected, when you log in, use the stty -a
command to
verify your terminal settings are as you expect, and you should be in business.
================================================================================
>From the archives:
summary of modem info
----------------------------------------------------------------------------
In response to the volume of requests I'm getting for "excellent summary",
here's a summary I received of info on setting up modems on the alpha.
Hope this helps some of you.
Subj: SUMMARY: hanging a modem off an alpha
Hi,
apologies for taking so long to post this summary.
The basic answers are (1) use the serial line, stty 38400, the stty
speed only has to be *higher* than the modem speed, not equal to it;
(2) to set up the modem, use the detailed instructions provided by
Steve Madsen, posted below. thanks Steve! (3) some of the alphas also
have an integral modem port, which supports speeds up to 19.2 Kbaud,
in addition to the solution of using the regular serial line, which
supports up to 38400.
Thanks to those who provided responses!:
-----------------------------------------------------------------------
Subject: Re: V.Fast modem on alpha/OSF1
>
> I would like to run a V.Fast modem (baud rate 28,800) on our
> alpha 3000/600s, running OSF1 V2.0. Does the alpha support
> this speed over the serial line (i.e. does 'stty 28800' work?)?
First off, you wouldn't want to merely set the port to 28,800 bps
anyway. Virtually all new modems, especially the fast ones, support some
sort of data compression protocol built into the hardware. In order for
this data compression to work well at high speeds, the modem needs to get
the data fast enough so that the compression time doesn't impact the "true"
data rate (14,400 or 28,800, whatever you're using). The newer protocols
(v.32bis I believe) can achieve ideal compression ratios up to 4:1, which
means that for it to reach this sort of throughput, you need to set the
port speed to 4x the connection speed. In this case, a 28,800bps modem
would have to have a port set to 115,200bps in order to achieve the maximum
throughput (which is really theoretical).
In practice, however, I generally get 1750 cps on a link that is
capable of 1440 cps, which works out to 1.2:1 compression. For a 28,800
modem, you should be able to get away with 38,400bps on your serial port
and still get good performance.
Now for why this matters... Alphas, at least our 3000/300, are
only capable of serial speeds up to 38,400. Or, stty only understands
speeds up to 38,400. So even though ideal conditions state you would want
115,200, you can't get that without special hardware.
> Also, if anyone has a set of instructions for hanging a modem
> off an alpha, please could you send me a copy?
Assuming this is for dial-in work, here's what you need to do:
Edit /etc/gettydefs and add a line similar to this:
dialin# B38400 HUPCL CS8 # B38400 HUPCL CS8 #login: #dialin
What this means: B38400 is the speed label (38,400bps). HUPCL
simply tells getty to stop asserting modem control on last close (whatever
that means). You need it, though. CS8 means use 8-bit characters. dialin
(the first one) is the label used for this entry, which we need when we
reference it from /etc/inittab. The last one is the label that getty will
go to if it cannot get a connection using these parameters. (Here we
aren't going to worry about stepping down to a slower rate.)
Next, edit /etc/inittab and add an entry for the serial port so you
can login:
dialin:23:respawn:/usr/sbin/getty -h /dev/tty00 dialin vt100
-h is not really needed. It's on our system because it works and I
got sick of messing around with it once I got it working. /dev/tty00 is
your serial port. dialin is the same label we used in the /etc/gettydefs
above. vt100 is the line discipline we wish to use (vt100 is pretty
standard for dial-in connections).
Now restart init by sending it a HUP signal. This will cause it to
reread the /etc/inittab file, where it will find your new entry for your
dial-in line, and start a getty for it.
One word about new modems: generally, a modem that can lock its
rate (the rate at which we are communicating to the serial port) needs to
be somehow told what the rate is before it can lock to it. They do this by
synchronizing to the rate the last AT command was issued at. If you can't
send AT commands to your modem by using 'echo AT >/dev/tty00' for some
reason (ours always tells us "operation would block"), you will need to do
it from a PC. MAKE sure that the speed on that PC is set to the speed you
want to use on your Alpha, otherwise things won't work.
Make sure when you set your modem up you configure it to use a
locked rate, use hardware flow control, use data compression, use error
correction, and then SAVE those parameters to the modem's non-volatile RAM.
Also make sure it's saved in the spot which is auto-loaded when the modem
first powers on (some modems have two save spots).
I know this sounds like a lot, but it should be all you need to
know to get your modem up and running for dial-in service on your Alpha.
Good luck!
-----------------------------------------------------------------------------
> I would like to run a V.Fast modem (baud rate 28,800) on our
> alpha 3000/600s, running OSF1 V2.0. Does the alpha support
> this speed over the serial line (i.e. does 'stty 28800' work?)?
> If not, does anyone know another way to support a v.fast modem ---
> e.g. is there a special card one can buy, or are there any plans
> at DEC to include this speed in future operating system upgrades?
>
> Forgive me if parts of these queries seem stupid or obvious, I
> don't know much about modems, serial lines or stty.
>
> Also, if anyone has a set of instructions for hanging a modem
> off an alpha, please could you send me a copy?
>
> Thanks very much for any pointers,
The DEC 3000 Model 600 has an integral modem port that supports speeds up to
19.2Kbps. The serial lines are actually implemented using a Zilog Z85C30
UART.
You may be able to find a third-party serial board that will run faster, or
you might even find a TurboChannel modem card (but I doubt it).
The DECpc AXP 150 and the Digital 2100 Model 500 systems both have EISA/ISA
capability, but at the present time, there is no support in DEC OSF/1 for
any modem cards as a direct peripheral.
There will be future "PC-like" systems (due out before the end of this year)
that will have the PCI bus, and in the fullness of time, there might be some
modem card support, but I certainly couldn't commit to it.
As for hanging modems off regular serial lines, it's typically no big deal,
as long as the modem is well-behaved. What you'll probably find lacking
(by comparison to PCs with Windows and fax software) is the easy to use kind
of interface that the PC world has come to take for granted.
Hope this is some help..
Tom
===============================================================================
In a nutshell:
connect the modem
(check cable (dos cable should work))
check inittab (setup as necessary (you will need 1 line for your modem))
check uugettydefs (you probably will not have to change this file)
do : init q
modem should show some signs of activity.
you could probably run setup and choose #6 UUCP and that would be the
easiest way.
I would look in a manual
================================================================================
Received on Thu May 02 1996 - 05:42:29 NZST