Dell Latitude C840 - Manual (Page 64)

The keypad numbers and symbols are marked in blue on the right of the keypad keys.
l To enable the keypad, press . The light indicates that the keypad is active.
l To disable the keypad, press again.
l To temporarily disable the keypad so that you can use the other function of a dual-function key, press and the desired key, or press
and the desired uppercase letter or shift function of the key.
Keyboard Shortcuts
System Functions
Display Functions
Power Management
NOTE: When you connect an external PS/2 keyboard or PS/2 keypad to the computer, the integrated keypad is disabled.
NOTE: If you experience problems using a password, ensure that the numeric keypad is disabled.
Opens the Windows Security window
Enables and disables the numeric keypad
Enables and disables scroll lock
Switches the video image to the next display in the following sequence: the integrated display, an external monitor, and both displays
simultaneously
Increases brightness on the integrated display only (not on an external monitor)
Decreases brightness on the integrated display only (not on an external monitor)