3.8. Joystick and Joyswitch 3.8. Joystick and Joyswitch Stick which can be moved left, right, forward or backward,
etc. It uses potentiometers to sense the movement. Some
joysticks allow the stick to be twisted to allow communication of
3rd degree of freedom.
Since difficult to finely control position of cursor, a joystick
can be used to control velocity and direction of screen cursor,
rather than absolute position. Centre position plus small dead
zone around centre => zero velocity: cursor not moving.
Like the joystick but instead of potentiometers there are eight switches situated up, down, right, left, up-left, up-right, down-left, down-right. (Possible to have another switch activated when stick is pushed down.)
These switches cause the cursor to move an amount in correct direction. (See sample exam paper.)
Video games have this: two or four switches to indicate direction: cursor (gun, blaster, spaceship) moves in correct direction at set speed until switch is released. Some have variable speed facility.
