Using a Telebit T-3000 modem on UNIX

Configuring the T-3000 modem

All modems should have been configured for you. In case the configuration is obliterated, here is how to do it.

Ensure that the A/B switch on the front of the modem is OUT, e.g. in A. Also ensure that the T/D is in the OUT position.

Type these commands. The "#..." text represents comments -- don't type this.

	at			# Wake up modem.  It should say "OK"
	at&f0			# Recall configuration 0
	att			# Use touch-tone dialing (atp for pulse)
	atl1			# Lower speaker volume
	at&c2			# Pulse DCD on hangup
	at&d2			# Drop call when DTR drops
	at&r3			# CTS handling
	at&s2			# pulse DSR on disconnect
	atx4			# Detect busy signals
	ats0=0			# Disable auto-answer
	ats58=2			# RTS/CTS flow ctl
	ats51=6			# Lock speed at 38400 baud (Sun-4, SGI)
-or-	ats51=5			# Lock speed at 19200 baud (Sun-3)
	at&w			# Write configuration into EPROM
	at&v?			# To view current configuration

Be sure that you have a 9-wire (or 12-wire) "full modem control" male-to-male cable.

Using a configured modem on a Sun

To initiate SLIP, run:

stip -s b394

This is typically done in /etc/rc.local.

To get access to the raw modem, to use it as a terminal, run:

tip dialer

and proceed with the section "Placing a call using the raw modem".

Using a configured modem on an SGI

To access the raw modem, to use it as a terminal, run:

cu -l ttyd2

and proceed with the section "Placing a call using the raw modem".

Placing a call using the raw modem

Type RETURN, "at" (the letters A and T, no quotes), and RETURN to wake up the modem. It will respond with "OK".

You can now given modem commands. The most usual one is to place a call. To call the 328 Annex Terminal Server from an ARL-APG internal phone, type:


while from an outside line, type:


This is a 10-line rotary.

If it works, you should get an acknowledgement message of "CONNECT 14400". If no message appears, press RETURN once to awaken the Annex terminal server. You will need to log in with your user name. The Annex password is the password in effect on your "mail home" machine. Use "rlogin" to access a network host.

To disconnect, log off the network host. Then give the command "hangup" to the Annex terminal server. The modem should confirm the disconnect with the message "NO CARRIER". Type


to force the modem to hang up your phone line. You should get an "OK".

To exit the TIP/CU program, type RETURN ~. RETURN. (Return, tilde, period, return). You should get your normal UNIX prompt back.

Note that for this example, no attempt has been made to use the "built-in" autodial features of the TIP/CU program, because (a) the versions of the program we have available don't know about the peculiarities of the T-3000 modems, and (b) because some extra workstation configuration is necessary.

When using TIP/CU, to download a file

It is necessary to run /bin/sh on the remote UNIX machine (such as VMB), because TIP/CU will send /bin/sh style commands across the modem on your behalf. You must also indicate that tabs should not be converted to spaces. Run:

sh stty tabs

Then you can use the TIP/CU command to retrieve a file:

~%take filename

Note that TIP/CU will spit out [hostname] after you type the percent sign, so that what is on your screen will look like:

~[IRIS]%take filename

When you are finished retrieving files, exit from /bin/sh using the "exit" command. If you type control/D instead, TIP/CU will blather half a screenful of error messages on your screen.

Also note that this only works for TEXT files. If you need to send a binary file, you must convert it to a printable form first, with UUENCODE. After moving it, the binary can be retrieved with UUDECODE.

TIP/CU document a ~%put command as well, but this does not work on SGI machines. You will need to write a tape to send data back to work.

Configuring SunOS 4.1.1 software

Follow the instructions in wolf:/d/mike/slip/slip-4.1-beta.README on how to install the kernel modifications to support SLIP.

Compile and install the "STIP" program from the sources in wolf:/d/mike/slip/stip.

Add these entries to the Sun's /etc/remote file:

dialer:dv=/dev/ttya:br#38400: b394:dv=/dev/ttya:at=hayes:pn=2786891:br#38400:du:\ :sa=\ :ls=/d/mike/.slip-b394

Changing the (ls) login script filename as appropriate, and set source IP address (sa) for your workstation. Destination address (da) is for bldg 394, and is for bldg 328. (br) is the baud rate, and should match the speed specified on the ats51= command given to the modem earlier. Note that a Sun-3 needs to run at 19200, while a Sun-4 can operate at 38400.

(sm) is the subnet mask, and won't change. (rt) means install default route when SLIP comes up, and you always want that. (du) means that this is a dial up line.

Edit /etc/rc.local on the Sun to add (after line 17) an automatic invocation of

# Initiate SLIP connection rm -f /var/spool/uucp/LCK* /usr/brl/bin/stip -s -v b394 &

if you desire your machine to establish network connectivity every time you power up your workstation. I run my machine this way. On those rare occasions where the phone is in use, or I know I won't be using the link at all, I just turn the power off to the modem before booting the Sun.

For safety's sake, I comment out these lines (not all adjacent):

##ifconfig -a netmask + broadcast + > /dev/null

#if [ -f /usr/lib/sendmail -a -f /etc/ ]; then # (cd /var/spool/mqueue; rm -f nf* lf*) # /usr/lib/sendmail -bd -q1h; echo -n ' sendmail' #fi

These lines need to be UN-commented:

if [ -f /usr/etc/syslogd ]; then echo 'starting system logger' rm -f /dev/log syslogd fi

At the end of /etc/rc.local, add these lines:

# ARL daemons if [ -f /bin/screenblank ]; then /bin/screenblank; (echo -n ' screenblank')>/dev/console fi

if [ -f /usr/mdqs/lib/mdqsdaemon ]; then rm -f /usr/spool/mdqs/qtmp/* (cd /usr/mdqs/lib; ./mdqsdaemon&) >/dev/console 2>&1 & echo ' mdqs' > /dev/console fi

In the file /etc/rc.boot, add this line after line 39:

# MJM mod: permit /etc/hostname.aa0 to define hostname *before* interfaces.

And then change line 61 from:

if [ "$1" != "xx0" ]; then to if [ "$1" != "xx0" -a "$1" != "aa0" ]; then

Comment out line 71:

##ifconfig -ad auto-revarp up

Then run these (substituting your own hostname on the ECHO command):

mv /etc/hostname.le0 /etc/.hostname.le0 echo > /etc/hostname.aa0

To finish installation, be sure to run:

chmod 666 /dev/ttya chown uucp /var/adm/aculog chown uucp /usr/spool/uucp

Configuring SGI IRIX 3.3.? software

Ensure that the dial&button box is wired to the DB-9 connector labeled "Serial 1". Ensure that the Telebit T-3000 modem is wired to the DB-9 connector labeled "Serial 2", and that the appropriate cable has been used. (pins 1-8 straight through, DB-9 pin 9 to DB-25 pin 20).

As root, run /usr/sbin/vadmin to configure ttyd1 (Port 1) as the dial & button box, and ttyd2 (Port 2) as "Off". (Port 2 will show as "modem" if it's been preconfigured for you).

Edit /usr/lib/uucp/Devices to have this as the first line:

Direct ttyd2 - 38400 direct

where the first word is capitalized, and the others are not.

After this point, vadmin will show Port 2 as a "modem", rather than "off". Now run:

chmod 666 /dev/ttyd2

You should be ready to run.

Please send E-mail to if you discover difficulties.

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