 In combination with the sprite-motion-related commands, it only took a single line of BASIC code to make a sprite move in the direction indicated by a connected joystick.A KEY command was available, which would set up the four function keys on the 64's keyboard to "enter" an arbitrary string.By default, these keys were set up to type commands like RUN, LIST, SPRDEF, GRAPHICS and others, but the user could change this using the KEY command in either direct mode or under program control.