The TApxVT100Emulator Class

Hierarchy Properties Methods

Unit:

AxTerm

Description:

The TApxVT100Emulator class emulates a Digital Equipment Corporation (DEC) VT100 terminal. It also supports some common extensions to the normal VT100 escape sequence set, namely support for multiple colors and support for inserting, erasing, and deleting characters.

The TApxVT100Emulator class provides support for the standard VT100 terminal modes. These are as follows:

·Line feed/newline: whether the line feed character inserts a new line or merely advances the cursor to the next line with a possible scroll.

·Cursor key mode: whether the cursor movement keys send application mode sequences or cursor mode sequences.

·ANSI/VT52 mode: whether the terminal interprets ANSI escape sequences or the restricted VT52 sequences.

·Column mode: whether the terminal displays 80 or 132 characters across.

·Scrolling mode: whether the terminal jump scrolls or smooth scrolls. Although the VT100 emulator maintains this setting, all scrolling is performed with jump scrolls.

·Screen mode: whether the display is normal or reverse-imaged.

·Origin mode: whether the home position for the cursor obeys the current scrolling region or not.

·Wraparound mode: whether the terminal wraps the cursor to column 1 of the next line when a character is displayed in the final column.

·Auto repeat: whether keys auto-repeat or not when held down.

·Interface mode: whether the terminal displays with 240 or 480 scanlines. Although the VT100 emulator maintains this setting, it does not perform any action when it changes.

·Graphic processor option: whether the terminal uses its GPO. Although the VT100 emulator maintains this setting, it does not perform any action when it changes.

·Keypad mode: whether keys on the numeric keypad send numeric characters or escape sequences.

There are several escape sequences sent by the host computer to which the VT100 terminal must respond. The VT100 emulator sends these responses:

Request
Response
Cursor position report
The position of the cursor (<Esc>[ row ; col R)
Status report
Terminal OK (<Esc>[0n)
What Are You?
Base VT100, no options (<Esc>[?;0c)
Identity request
VT100 acting as VT52 (<Esc>/Z)