Keyboard

The main way to enter commands and text information in Logo is via the computer keyboard. In many respects the keyboard in Logo operates like a typewriter: letters and numbers that are typed appear in the Listener window and are read into Logo workspace when you press ENTER. In this method you can type Logo commands and watch Logo perform the action you specify when you tell it to read and act on the commands by pressing ENTER.

Function Keys

Most computer keyboards contain special keys called function keys that begin with the letter F and are numbered from 1 to 10 or 1 to 12. The Windows operating environment utilizes these function keys to execute certain common commands. These commands work while you are using Logo as well. Consult your documentation for Windows for a listing of the function key commands.

Logo also built-in function key commands that operate when the function key is pressed in conjunction with the SHIFT key. These commands are: Logo allows you to change commands that will be executed when a function key is pressed in conjunction with the SHIFT key. Each SHIFT-function key combination is a system variable which can be defined to perform the Logo command you prefer. The system name FKEY.n is assigned to each function key where n represents the number of the function key. By changing the definition of FKEY.n you change the action performed when you press SHIFT and the specified function key.

The SHIFT+F2 key combination issues the SPLITSCREEN command. You can change the effect of this key combination by redefining the variable FKEY.2 using the Logo command MAKE.

MAKE "FKEY.2 "HELLO

causes the text HELLO to be printed when you press SHIFT+F2 and ENTER. For a command stored in a function key variable to be executed without the ENTER key being pressed, the ENTER character can be appended to the end of the command you assign. This can easily be done with the CHAR command.

MAKE "FKEY.2 WORD "DRAW CHAR 13

This causes the Logo command DRAW to be executed automatically when you press SHIFT+F2.