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			VTED
		KEYBOARD DISPLAY EDITOR

     VTED is a very basic editor for use on any keyboard
display terminal. It has only seven special function keys which
are used for editing: Cursor-up, Cursor-down, Cursor-right,
Cursor-left, Rubout, EOL, and EOS.
The philosophy of this editor is simple:
What you see is what you get!  In other words, whatever appears
on the display screen is what is in your file.  For instance, there
are never any extraneous characters on the screen such as Backslashes
or the echoes of rubbed out characters. When a rubout is hit, the
cursor backs up over the last character typed and deletes it. If
the cursor is at the beginning of a line and a rubout is typed,
then the <CR> is deleted from the file and the cursor is placed
at the end of the previous line.

The following is a description of the operating proceedures
of VTED:

Starting VTED:

	.RUN VTED

	FILE NAME?	(User now types name of file to
			be created or edited)

			If the file already exists, VTED
			will respond with:

	FILE ALREADY EXISTS
	DO YOU WANT TO: PROOF, APPEND, OR OVERWRITE?

			(The user should now answer with a "P",
			"A", or "O".)

VTED options:

1)	If the file name supplied by the user did not previously
	exist, then the screen will go blank signaling that the editor
	is ready to accept text.  From this point on all text entered
	through the keyboard is put into the specified file.

2)	If the file specified by the user already exists on the disk,
	then the user has three options available:

   A)	The user may OVERWRITE the existing file.  This
	causes a new file to be started with the specified name, and
	the old file is renamed to a file with the same name but a 
	unique extension.  The screen will then go blank signaling
	that the editor is ready to receive text.

   B)	The user may APPEND text to the end of the specified
	file.  This causes the specified file to be opened and 
	scanned to it's end.  The editor will type out the last
	five lines previously entered into the file, and will start
	accepting text to be appended to the end of the file.

   C)	The user may PROOF the specified file.  This option
	causes the specified file to be renamed to a file with the
	same name and a unique extension.  Then a new file with the
	specified name is opened.  This file is empty at the start,
	and the internal buffer of the editor contains all of the text
	from the original file.  The user can proof the original
	file by using the Cursor Control keys to scan through the
	file a line at a time, making edits when necessary.  The screen
	goes blank at the start when the editor is ready to receive editing commands.

VTED Commands:

Cursor-up
	Position the cursor at the end of the previous line. All
	text which is passed over is placed in the internal buffer
	of the editor. This text can be added to the file again with
	the Cursor-right or the Cursor-down commands.

Cursor-down
	Add text up until the next <CR>
	from the internal buffer to the end of the file.
	If there is no text in the internal
	buffer then this command will do nothing.

Cursor-left
	Move the cursor left over one word. Put all text passed over
	into the internal buffer.  If the cursor is at the start of
	a line, move the cursor to the end of the previous line.

Cursor-right
	Move the cursor right one word.  A word of text is taken from
	the end of the internal buffer and is added to the end of the
	file.

Rubout
	Rubout one character to the left.  The cursor will be moved
	to the left one space and that character will be deleted from
	the file. The rubbed-out character will not be placed into
	the internal buffer of the editor. If the cursor is at the
	start of a line, the <CR> will be deleted form the file
	and the cursor will be moved to the end of the previous line.

EOL
	Erase through the end of the current line, including the
	<CR> at the end of this line.  This key is used for deleting
	a whole line at a time instead of using multiple rubouts.

EOS
	Erase through the end of the file.  This command is used
	to delete all text from the current cursor position through
	the end of the file.  Any text in the internal buffer is
	also deleted.  Because of the severity of this command,
	VTED requires that two EOS characters be typed before
	any deleting is performed.

Inserting text with VTED:

	Text is inserted into the file by moving the cursor to the
	desired location with the Cursor moving commands, and then
	just typing the text to be inserted.

Deleteing text with VTED:

	Text is deleted by positioning the Cursor at the end of the
	word to be deleted, and then typing a Rubout for each character
	to be deleted.

Exiting from VTED:

	To Exit from VTED the user types a <CNTRL>C.  This will
	cause the editor to close out the file, appending any text in
	the buffer to the text already entered.

Upper and Lower Case Characters:

	VTED always accepts both upper and lower case characters.  However
	on terminals such as the VT-05 where the keyboard is both upper and
	lower case and the screen is only upper case, VTED will simulate
	upper case characters by placing a "^" in front of all upper case charactrers.
	This allows the typist to see if a character was entered as an upper
	or lower case character at a glance.  If the terminal being used
	is capable of displaying both upper and lower case characters, then
	the user should turn on lower case mode before starting the editor
	(Use the monitor command "SET TTY LC").  Likewise, if the
	terminal being used does not have an upper and lower case keyboard
	then the user should also give the "SET TTY LC" command
	to signal the editor not to put a "^" in front of every upper case
	letter. (VT-06's fall into this catagory).

VTED Design Goals

   A)	VTED was written to be used by the casual computer user.
	Since there are only a limited number of commands which are
	graphic in nature, VTED is easy to learn and easy to
	remember even if the computer is used very infrequently.
   B)	VTED is best suited for a terminal running at 300 baud
	or greater.
   C)	With the upper and lower case
	capabilities built into the editor, VTED is an excelent
	entry program for RUNOFF text.
   D)	VTED does automatic checkpointing of the file that is being
	created.  The file is kept on the disk on a line by line basis.
	Thus if the system crashes during an editing session, the only
	information that is lost should be any partially typed
	lines.

VTED Quirks:

   A)	VTED will not let the typist enter a <LF>. If the
	<LF> key is struck, VTED rings the terminal's bell
	and turns the <LF> into a <CR>. This feature exists
	because RUNOFF gets very ill when it sees a <LF>
	and no preceeding <CR>.
   B)	VTED will not allow a FORM FEED (<CNTRL>L)
	to be entered unless it is preceeded by a <CR> or another
	FORM FEED. If an attempt is made to enter a FORM FEED
	incorrectly, VTED will ring the bell and insert a <CR>
	before the FORM FEED.
   C)	VTED tries to determine the baud rate at which the terminal
	is operating.  This is done by timing the typeout of a string
	of characters.  If the system is heavily loaded, this calculation
	may not be correct. To insure that the correct number
	of fill characters will be used for the higher speed terminals,
	the user should set the correct filler class before starting
	VTED. This is done with a "SET TTY FILL n"
	command, where n is: 0 for 300 baud or less, 1 for 600 baud,
	2 for 1200 baud, and 3 for 2400 baud.
   D)	Since VTED is simulating uppercase characters by typing
	an uparrow in front of each uppercase character, the editor
	must run in "no echo" mode and must do it's own echoing.
	This sometimes causes a delay in the echoing of typed characters
	on a heavily loaded system. Hopefully the experienced typist
	will not notice this lag in echoing.