                             VT_TERM
                     A Simple VT-100 Emulator

Background:

Back in 1989 I needed to test out a communications library.  Not
having any other idea of what to do and having a VT-100 reference
card handy, I wrote a VT-100 terminal emulator.  It only took
about 4 hours and was so handy that I later went back and spent
another morning adding simple file transfer capabilities.  The
company I worked for at the time did automation for the oilfield
and pipeline industry, and we used to give folks VT_TERM to use
with the monitor port we liked to hang on our equipment.  It's
small (27K), robust (never had it crash) and supports everything
a VT-100 does with the exception of double-high and double-wide
characters.  The sequences are accepted, they just don't do
anything.  It will show the PF1 - PF4 indicators, but I don't
think I put in any way to send the keys (sorry, but it *was*
just a quick test program).  There's also no online help.


Operation:

VT_TERM is a simple DOS executable and can be run from FILER on
the HP200LX.  There are no command line arguments.  It will
display a version message for about 2 seconds, then go to the
main screen.  The bottom line of the screen is the status /
control line and can be in one of three modes.  All program
control is via the function keys.  The three modes and the
function key assignments for each mode are as follows.


Status mode:

The program will always start in STATUS mode.  In this mode, the
status line starts out as:

F1-HDX F2-CLS F3-BRK F4-XFER   F9-DUMP F10-EXIT | VT100 FDX

On the left you have the function keys and their effects, on the
right are the status indicators.  This line shows that the
program is currently in VT100 mode and Full Duplex.

The function keys have the following effects:

<F1>  will put the program in Half-Duplex mode
<F2>  will clear the screen
<F3>  will send a line break to the Host system.
<F4>  This opens a pop-up window that lets you choose one of the
      few available transfer options - basically just ASCII up or
      download, plus a capture capability.
<F9>  This will take you to the next command mode, known as DUMP 
      mode.  DUMP mode is explained below.
<F10> The <F10> key will *always* exit you from VT_TERM.  There
      is *NO* verification or warning, so do be careful.  

The status indicators are:

VT100 / VT52  - mode indicator
FDX / HDX     - Duplex mode - Full or Half
^             - A caret character will be displayed while SHIFT
                is down.
CAP           - will be displayed while CAPS lock is on.
PF1 - PF4     - If VT_TERM receives the correct sequences, PF1 -
                PF4 indicators will be displayed.


Dump mode:

Pressing <F9> while in STATUS mode will put the program in DUMP
mode.  In dump mode the status line shows the hex values for the
last eight bytes received from the HOST and sent by the TERMinal. 
The only status indicator is FDX / HDX, and the only labeled
function key is <F9> for moving to COMM mode (explained below). 
<F10> is, as always, active and will exit the program.  Dump mode
is handy when you're trying to get systems to communicate.


Comm mode:

Pressing <F9> from DUMP mode takes you to COMM mode.  In Comm
mode, you control all of the communications settings.  The status
line shows the active function keys, what setting they control,
and the current value.  Pressing a function key steps the setting
to the next available value.  The function keys and their
settings are (startup defaults shown):

F1-PORT(1)     - This controls which port is used - COM1 or COM2.

F2-BAUD( 9600) - Available baud rates are:
                  110, 300, 600, 1200, 2400, 4800, 9600, 19200.

F3-PAR(N)      - Parity - valid settings are:
                  (N)one, (O)dd, (E)ven, (M)ark, and (S)pace

F4-DATA(8)     - Number of data bits - 5, 6, 7, or 8

F5-STOP(1)     - Number of stop bits - 1 or 2

F6-VT100       - Terminal emulation mode - VT100 or VT52

F9-STATUS      - Pressing F9 takes you back to STATUS mode.

As always, <F10> will exit the program.


Summary:

That's it, a simple little VT100 terminal emulator that works on
the HP and just about any other machine I've ever tried.  You may
use it and may give copies to others, but you may *NOT* charge
for the program or include it in a collection for sale.

Send comments, suggestions, good jokes, and maybe a postcard to:

Steven Van Dyke
7918 N. Central
Kansas City, MO 64118-1417

70611.2147@compuserve.com  (or just 70611,2147 if you're on CIS)


