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Q83064: Using ANSI.SYS /X to Remap Extended Keys

Article: Q83064
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:4.0,4.01,4.01a,5.x,6.0,6.2,6.21,6.22
Operating System(s): 
Keyword(s): msdos
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 4.0, 4.01, 4.01a, 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
=======

Microsoft MS-DOS version 4.0 introduced a new feature to the ANSI.SYS console
device driver, used by specifying the /X switch. With the /X switch, ANSI.SYS
can distinguish the extended keys (RIGHT ARROW, HOME, and so on) from the keypad
keys (with NUM LOCK off) on some extended keyboards. This allows you to redefine
the keys separately using ANSI escape sequences. Extended keyboards are also
called 101- or 102-key keyboards.

If you have an extended keyboard and want to redefine an extended key (or keypad
key) without also redefining the corresponding keypad key (or extended key) to
another character, you must load ANSI.SYS with the /X switch.

MORE INFORMATION
================

Non-ASCII keys (function keys, SHIFT keys, extended keys, and, when NUMLOCK is
off, the keypad keys) differ from the ASCII keys in that they send an
identifying code to the input buffer, followed by the key's value. ANSI.SYS
recognizes this and reads the input buffer a second time after receiving the
identifying scan code.

Most keyboards only send the 00H scan code for all non-ASCII keys. Many extended
keyboards send a scan code of 0EH (224 decimal) for the extended keys and a 00H
for the corresponding keypad keys. ANSI.SYS can only detect the difference
between extended and keypad keys with the latter type of keyboard.

The following example remaps both HOME keys to issue the DIR command on an
extended keyboard. In CONFIG.SYS:

  device=c:\dos\ansi.sys

In AUTOEXEC.BAT:

  set prompt= $e[0;71;"dir";13p $p$g

The following example remaps the HOME key on the number pad to issue the DIR
command, and the gray HOME key to issue the CLS command on an extended keyboard.
Add the following to the CONFIG.SYS file:

  device=c:\dos\ansi.sys /x

In AUTOEXEC.BAT, add the following:

  set prompt= $e[0;71;"dir";13p $e[224;71;"CLS";13p $p$g

NOTE: The lowercase "p" characters in the above command must be lowercase. In the
above commands, the space included before each dollar sign ($) is optional, and
is only added for clarity.

REFERENCES
==========

"Microsoft MS-DOS User's Guide and Reference," version 5.0, page 593

Additional query words: appnote 6.22 4.00 5.00 5.00a 6.00 6.20

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Keywords          : msdos 
Technology        : kbMSDOSSearch kbMSDOS400 kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS500 kbMSDOS401 kbMSDOS500a
Version           : MS-DOS:4.0,4.01,4.01a,5.x,6.0,6.2,6.21,6.22

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