Numeric Keypad Behavior in VT Emulation

  • 7021747
  • 02-May-2008
  • 31-Mar-2018


Reflection for UNIX and OpenVMS version 13.0 through 14.x
Reflection for HP version 13.0 through 14.x
EXTRA! X-treme version 9.x


This technical note explains how the numeric keypad functions when you are connected to a UNIX or OpenVMS host as a VT terminal. This information may be of particular interest if pressing keypad keys results in garbage characters displaying instead of numbers.


What Determines Keypad Behavior?

When you are connected to a UNIX or OpenVMS host and press keys in the numeric keypad, what gets transmitted to the host depends on:

  • The terminal type you have configured in your session.
  • The keypad mode that is set by the host.
  • Any keyboard mapping you may have configured in EXTRA! or Reflection.

These factors are explained below.

Terminal Type

If your terminal type is not properly set for your host, the keypad may not transmit the expected values. Where you check terminal type settings depends on your emulation product and version.


Click Setup > Terminal > Terminal Type tab to check your configuration.

What you set in Terminal Setup is also used as a basis for terminal type negotiation when the Telnet connection is established. To check or set a different value, click Connection > Connection Setup > More Settings. If the host does not accept this value during Telnet negotiation, the Terminal default (on the Advanced tab) is used.


Click Options > Settings > Connection > General. In Terminal Type Negotiation, select "Use only the following type" and enter an appropriate value (such as VT220) in the field.

Keypad Mode

The numeric keypad mode is set by your host application. In normal numeric mode, the keypad transmits numbers. In application mode, the keypad transmits escape sequence codes. (How the host sets the keypad mode may depend on your terminal type.)

To check your current keypad mode in Reflection, click Setup > Terminal > Keyboard tab.

The host changes the keypad mode by sending certain codes (such as ESC=, ESC>, CSI?77h, or CSI?66l). For more details about escape sequence control codes, see KB 7021621.

Keyboard Mapping

If the numeric keypad key mappings are changed in your Reflection settings file or EXTRA! session file, then any keypad mode escape sequences from the host can be effectively ignored. For more information on mapping the keypad keys in Reflection to always transmit numbers, see KB 7021608.

Additional Information

Legacy KB ID

This document was originally published as Attachmate Technical Note 2346.