Ansi.sys

Ansi.sys is an enhancement of the "CON" device driver built into Command.com. It can be used to modify the default display colours, the starting position of the cursor, and the mapping of keys. It can also be used to change the video mode.

Syntax

Ansi.sys can only be loaded in Config.sys using a Device or DeviceHigh statement:

Device=[Path]Ansi.sys [/X] [/K] [/R] or
DeviceHigh=[Path]Ansi.sys [/X] [/K] [/R]

[Path]	The full path. Default is the root directory of the start-up drive (usually C:/)
/X	Enables remapping of the extended keys on a 101-key keyboard.
/K	Causes a 101-key keyboard to behave as an 84-key keyboard.
/R	Reduces the scrolling speed when long documents are printed to the screen.

Notes

For reasons beyond my comprehension, the designers of ANSI.SYS decided that all commands issued to it would be prefixed with the ASCII code assigned to the "Esc" key followed by an opening square bracket ( [ ). Unfortunately, the designers of Command.com had already reserved the "Esc" key as a means of cancelling the current command line. It is thus impossible to send an ANSI.SYS command directly from the DOS command line. Three ways to overcome this rather peculiar conflict have been developed:

• Use the PROMPT command along with the "$E" special character.
  Although primarily used for generating fancy/informative prompts, usually in Autoexec.bat, the PROMPT approach is handy for quick-and-dirty testing of sequences from the command line. After using PROMPT this way, don't forget to reset the prompt when done!

  For examples, see PROMPT.

• As mentioned above, entering the "ESC" character on the command line causes the command to be cancelled. However, when a file containing the "ESC" character is copied to the screen (using the TYPE or COPY filename CON commands) or is encountered in a batch file, the character is accepted for what it is and the command/statement is processed without a hitch. Thus Ansi.sys sequences can be sent to CON either via a text file or a batch file. In either case it is necessary to use a text editor that can handle the "ESC" character.

  Text Editor	To enter the "ESC" character	Displays as:
  Edit	Ctrl-P followed by "ESC"

Examples

1. 1. Use EDIT to create Keys.txt:
      [0;46;"COPY"p[0;32;"DIR c:\data"p
      (where is inserted using Ctrl-P followed by Esc)
   2. Copy Keys.txt to the screen using either:
      TYPE Keys.txt or
      COPY Keys.txt CON

   Or

2. 1. Use EDIT to create Keys.bat:
      ECHO [0;46;"COPY"p
      ECHO[0;32;"DIR c:\data"p
   2. Run the batch file by entering "Keys" at the command line prompt.

Either way, the keys will now be (re)assigned.

The Codes

In all the following, "Esc" indicates the character associated with the "Escape" key on the keyboard. This cannot be entered directly because Command.com interprets this keystroke as a request to abort the command currently being entered.

Ansi.sys codes ARE case specific.

Character Attributes and Colours

Cursor Positioning

Miscellaneous

To change the Display Mode:

Keyboard Layout Codes

Ansi.sys can be used to remap the keys of the keyboard. Any key can be redefined to any one or more characters of the extended ASCII character set.
Typical applications of this facility include:

• Assignment of "non-standard" characters to unused keys
• Assignment of text phrases to unused keys (including DOS commands)
• Complete remapping of the keyboard - for special data entry functions or obscure foreign language use, perhaps.

Syntax

keycode	The code(s) associated with the given key. Many keys use a code of two numbers separated by a semicolon and these must be used in full.
string	The ASCII code for a single character, or a text string (of one or more characters) enclosed in inverted commas

Examples

1. To assign á to the Alt-F1 key:
   "Esc"[0;104;193p

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