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Compaq DEC Text Processing Utility AA-PWCBD-TE User Manual

Page 140

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DECTPU Terminal Support
B.1 Using Screen-Oriented Editing on Supported Terminals

132-Column Mode

Only terminals that set the DEC_CRT mode bit and the advanced video mode
bit can alter their physical width from 80 columns to 132 and back. All other
terminals keep the physical width that is set when you enter the editor.

For the DECTPU screen manager to behave predictably on GIGI terminals, you
should report the terminal width as 84 to OpenVMS systems. Use the DCL
command SET TERMINAL/DEVICE=VT100 to set the proper terminal width.

Autorepeat ON/OFF and Auxiliary Keypad Enabling

To take advantage of the SET (AUTO_REPEAT) built-in procedure or to
enable the auxiliary keypad for applications mode, the terminal must be set
to DEC_CRT3, DEC_CRT2, DEC_CRT, or VT100. Use the DCL command SET
TERMINAL/DEVICE=characteristic to set the terminal.

Control Sequence Introducer

DECTPU can use one 8-bit control sequence introducer (CSI) to introduce a
terminal control sequence. (Usually you use the 2-character combination of the
ESCAPE key and the left bracket ( [ ).) To take advantage of this feature, set your
terminal to DEC_CRT2 mode. The Compaq VT300-series and VT220 and VT240
terminals currently support this feature.

Cursor Positioning

If your terminal sets the DEC_CRT mode bit, DECTPU assumes that when
control sequences that position the cursor to row 1 or column 1 are sent to the
terminal, the 1 can be omitted. If your terminal does not behave correctly when it
receives these control sequences, you must turn off the DEC_CRT mode bit. Some
foreign terminals may not be fully compatible with DECTPU and may exhibit this
behavior.

Edit Mode

Terminals that are operating in edit mode allow the editor to take advantage
of special edit-mode control sequences during deletion and insertion of text
for optimization purposes. Some current Compaq terminals that support edit
mode include the VT102, the VT220, the VT240, the VT241, and VT300-series
terminals.

8-Bit Characters

ANSI terminals operating in 8-bit mode have the ability to use the supplemental
characters and control sequences in the DEC Multinational Character Set. The
Compaq VT300-series and the VT220 and VT240 terminals currently support
8-bit character mode. If you have the 8-bit mode bit set, DECTPU designates
the DEC Multinational Character Set into G2 and invokes it into GR. For
more information on how your terminal interacts with the DEC Multinational
Character Set, refer to the programming manual for your specific terminal.

Scrolling

DECTPU uses scrolling regions only for terminals that have the DEC_CRT mode
bit set. On other terminals, DECTPU repaints the window when a scroll would
have been used (for example, when a line is deleted or inserted).

Video Attributes

When you set the video attributes of windows, markers, or ranges, only those
attributes supported by your terminal type give predictable results. Most ANSI
CRTs support reverse video. However, only terminals that support DEC_CRT
mode with the advanced video option (AVO) have the full range of video attributes
(reverse, bold, blink, underline) that DECTPU supports.

B–2 DECTPU Terminal Support