PHUN With...
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               (An introductory guide to those 
               mysterious green-screened monsters)              


Dumb terminals have been used with computers since the advent of mainframe
computers.  All that a dumb terminal is, is an input/output device that is
attached to a larger, more powerful computer via a serial connection, modem,
or other network connection.  There have been many different kinds of
terminals created since the idea first came into play.  Some of the more
popular ones were the Televideo Terminal, and Digital (DEC)'s VT 100, 102, and
400 terminals.  You can still find these terminals in libraries, stores,
colleges, and some offices.  Essentially, all that these terminals contain
is a CRT (Screen), a keyboard, and inside the body of the monitor, is a
circuitboard, which contains some ROM chips with some hard-coded programs
(This included information for some specific emulation functions, the setup
program, and the standard boot-up, connection, and self-test functions), as
well as a small amount of RAM (used for Input, Communication, and print
buffers), but there is also an area of EEPROM.  This, in conjunction with
the setup program, is going to be a major part of this article.

Why would you want to mess with these terminals?

Well, there are many reasons why one would want to mess with them, or at least
get familiar with them.  At stores, you might see one of these just out in the
open, and unattended.  Some stores i know of (such as Comp-USA), they have the
terminals on the sales floor so that sales people can look up prices, quantity
in-stock, and other information about the merchandise, in case a customer has
a question, or if they can't find what the customer wants (which happens so
often that you stand a better chance of finding it yourself).  Now, if only
you knew how to use it... Well, every place has their own software, and i can
not spend my time telling you the ins and outs of each individual software.
I've also seen these terminals in libraries, used for electronic card
catalogs.  Dumb terminals are easily distinguished by either a nasty Green,
amber, or white/grey screen, attached directly to a keyboard. You can find out
about each terminal and what kind of software is being run once you find one
of them logged in.

You need to find the set-up hotkey sequence.  Some of the DEC terminals just
use F3.  (if there's an F-key or other non-alpha-numeric key that seems to
have been torn off, there's a good chance that's the one you're looking for.
This was the case in a blockbuster video i was at a few weeks ago, where they
had a terminal up and running for Blockbuster patrons to look up rental
availability, new releases, up-and coming rental release dates, etc).  On
Televideo Terminals, There's always (or at least I've always seen) a key close
to the upper right hand corner of the keyboard, kind of where the F-keys are,
and it's labeled:

 Set Up
 -----------
 <something>

I can't remember what the option on the bottom of the key is, but you just
have to hit the Shift Key, and that key at the same time.

The Set-Up Menus
----------------
These vary drastically from one terminal to the next.  You're almost always
guaranteed to find out more about the software that the establishment you're
messing with is using, just by looking at the programmed macros.  If you're
feeling evil, write the settings down, and change them on that terminal.
You can usually change some normal system settings, such as Reverse Video
mode, Connection Speed, printing (if there's a printer), and in some cases,
you can access a log of keystrokes (hee hee!).  A very few terminals allow the
user to define their own custom emulation settings, allowing an advanced, and
properly informed user to set a Televideo terminal to handle VT, 3270, Prism,
and many others.  

Dumb terminals are great if you just want to hit some dial-up unix shell
accounts or get on bulletin boards.  You can usually hook a modem up directly
to it and go to town.  This works best with VT series terminals, because the
VT-100 + emulation settings are very similar to the ANSI codes that many BBSes
use.  If you don't have a VT terminal, most unix systems allow the user to
define the terminal type, and it will slip into that emulation mode.

This article doesn't really cover many specifics, other than to point out that
these pieces of equipment which have been labeled completely obsolete, still
have value and function, and not only to the hacker.  I wish it was possible
for me to show exactly how to get into setup (and what you can do once you're
in there) on as many different models as possible, but I can't, simply because
it's different for each brand, and between models.  Sometimes it's just fun
to hack around trying to find the cool little "secret" menus.
