                Full-Screen Editor for DX-FORTH
                -------------------------------

                      *** IMPORTANT ***

  After editing a screen, Ctrl-K must be pressed to UPDATE
  the changes.  This is a safeguard as there is no backup
  copy of the source file being editing.  Until Ctrl-K is
  pressed, the screen may be restored to its previous state
  using Ctrl-L.


INSTALLATION:

DX-FORTH for CP/M must be configured for your terminal before
using the full screen editor.  See DX-FORTH.TXT for further
details.


INVOKING:

The screen editor is invoked typing SED.  If the editor is not
resident it is automatically loaded from the disk file SED.SCR.

If you mainly use screen files you may want to add EDIT as a
synonym for SED e.g. AKA SED EDIT

DX (COM or EXE) comes pre-loaded with the screen editor.


COMMANDS:

 SED  ( n | -- )

   Enter the full screen editor, selecting screen n for
   editing.  If no screen number is specified, then the screen
   last LISTed is used or, in the case a LOAD error, the screen
   and position where the error occured.

   Note: If the screen number is out of range, then the highest
   screen available is used.  If the size of the screen file
   was zero when EDIT was called, it will be extended by one
   block.

 L  ( -- )          List

   Lists the current screen.  The screen number is obtained
   from the variable SCR which is set by LIST, EDIT or when a
   LOAD error occurs.

 N  ( -- )          Next

   Increment the screen number in variable SCR then list it.

 B  ( -- )          Back

   Decrement the screen number in variable SCR then list it.

 LS ( -- )          List Swap

   Perform SWAP-FILE and list the screen specified by SCR.


EDITOR COMMANDS:

1. Cursor movement

Ctrl-E   Move cursor up
Ctrl-X   Move cursor down
Ctrl-D   Move cursor right
Ctrl-S   Move cursor left
Ctrl-I   Move cursor 4 places to the right (TAB)
Ctrl-Q   Move cursor to the upper left of the screen

2. Editing

Ctrl-G   Delete character to the right of the cursor
Ctrl-H   Delete character to the left of the cursor
Ctrl-T   Erase all characters to the right of the cursor
Ctrl-O   Insert space at the current cursor position
Ctrl-Y   Delete the current line. Lines below cursor are moved
         up one position. Pop a line from circular buffer into
         the bottom line
Ctrl-N   Insert blank line. Lines below cursor are moved down
         one position. Push bottom line to the circular buffer
Ctrl-W   Split the current line at the cursor position
Ctrl-F   Join the next line at the cursor position
Ctrl-A   Copy the contents of the current line to the one-line
         buffer
Ctrl-P   Copy the contents of the one-line buffer to the
         current line
Ctrl-K   Update all changes made to the screen

3. Miscellaneous

Ctrl-C   Move to the next screen
Ctrl-R   Move to the previous screen
Ctrl-J   Jump to another screen
Ctrl-B   Redraw the screen. Used if the screen has become
         garbled e.g. after displaying blocks containing binary
         data
Ctrl-L   Reload the current file block
Ctrl-V   Toggle between insert or overwrite mode
Ctrl-U   Exit the editor
Ctrl-Z   Multi-function command
         S - clear the screen contents
         B - clear the circular buffer contents
         I - insert a blank screen at the current position
         D - delete the current screen copying it to the buffer
ESC      Toggle between normal and graphics mode

4. Utilities

The following commands are available from the EDITOR vocabulary

 IMPORT  ( n1 n2 -- )

   Copy screens n1 thru n2 from the secondary file inserting
   them beginning at screen SCR of the current file.

 EXPORT  ( n1 n2 -- )

   Copy screens n1 thru n2 from the current file inserting
   them beginning at screen SCR of the secondary file.

IMPORT and EXPORT assume two screen files are currently open
and SCR of the target file has been set (SCR may be viewed with
FYI).  After the operation, target SCR is set to the last block
written plus 1.

5. Notes

In the DOS version of the editor, the arrows keys, PgUp, PgDn,
Home, Insert and Delete keys may be used in addition to the
usual control-key sequences.

COPY COPIES EXPAND (found in earlier versions of the editor)
are redundant as the ability to insert or delete screens is now
available from Ctrl-Z.

To extend a screenfile, enter EDIT then jump to the desired
screen number using Ctrl-J.  Alternatively, truncating/
extending a screenfile may also be done from the Forth
environment using FILEBLOCKS.

A special graphics mode has been added.  It is toggled via the
ESC key and allows graphic characters to be entered from the
keyboard.  It is intended to allow the insertion of PC symbols
or graphic characters into quoted strings.  Refer to
DX-FORTH.TXT for a table of keys and their corresponding codes.
To exit graphics mode, press ESC again.

