Since these machines ran a custom OS based on the Lisp programming language, the layout has a few peculiar features:
- Since Lisp is heavy on parentheses, the keys next to 'P' produce parentheses without having to press Shift.
- The keyboard has an unusual amount of modifiers and extra "shift" keys which allow to type extra characters or have more levels of key bindings.
- There are "Network" and "Local" keys to switch between a local or remote prompt.
Other special features include:
- The key next to 'A' is captioned Rubout and behaves like an extra backspace or delete key.
- The other backspace sits one row lower than on PC keybaords and is a small key.
IO System of the Lisp Machines (1981)
(see pages 276.. in the LIP MACHINES MANUAL (3rd ed;1981) ).
Buttons on the keyboard
- PAGE Enter a page separator.
- RUB OUT delete character to the left.
There are no control charecters as in ASCII, so CONTROL just sets the control-modifier bit.
If SHIFT is pressed along with CONTROL and/or META, it sets the hyper modifier-bit!
Example: Pressing CONTROL-SHIFT-A does not produce C-A instead of C-a, but H-A.
The code-table on page 279 shows not all characters and symbols on the Space Cadet keyboard. However, the 4 hands and I-IV are present. See also pages 287/288. For an example how to use the hands symbols, see p. 437.