Control 2 servos with an Atari Joystick

Discussion in 'The Projects Forum' started by jonman24680, Sep 11, 2009.

  1. jonman24680

    Thread Starter New Member

    Sep 11, 2009
    This is my first post on this forum.

    I am working on my senior design and am running into a problem with controlling servos. I want to start off saying that I want to build the circuit not just buy a controller. I figure I can start off by controlling 1 of the servos then the other one will be just a copy.

    I want to also say that I have never messed with servos before. I have read a lot about them and know what they do and how they do it. What I need help with is the actual control circuit. I want to be able to move the Joystick to the right position and the servo smoothly turns clockwise as a certain speed, then release the joystick and it stops, I also want to be able to move the joystick to the left position it the servo smoothly turns counter-clockwise.

    If it is not possible to make it turn smoothly then I will be ok with a little jerky motion but the smoother the better, since I am trying to aim the servos at something.

    Also some information about an Atari 2600 Joystick: It gives logic 1s when the joystick is pressed in that dirrection.

    Thank you in advance for any information/help with this.

  2. beenthere

    Retired Moderator

    Apr 20, 2004
    That joystick simply closes a light duty switch when moved. You could use that switch to control an external relay that actually puts voltage (and a much larger current) to the motor.

    It's not a servo control as it is simply on/off.
  3. jonman24680

    Thread Starter New Member

    Sep 11, 2009
    I think I understand what you are saying but how would I make it turn counter-clockwise when the other direction is pressed? Also what would that relay look like since I have to use servos for a later part of my project?
  4. blueroomelectronics

    AAC Fanatic!

    Jul 22, 2007
    Servos generally need a microcontroller to do anything fancy. Which microcontroller will you be using?
  5. jonman24680

    Thread Starter New Member

    Sep 11, 2009
    I was hoping that I wouldn’t have to use a microcontroller. But if it is a must could you give me any suggestions? Also I guess I would need a 2 channel one, I’m trying to keep cost really low as I am a poor college student.
  6. Steve C

    Active Member

    Nov 29, 2008
    I think your best bet is a motor attached to a gearbox. The switches will control relays in a 5-wire configuration. If you can't find cheap gearbox motors at your local hobbyshop, I would "imagine" that you can convert a hobby servo by eliminating ALL of the control circuitry and hooking up the DC motor straight to your power source.

    The reason I think this is the way to go is because that joystick is digital, not analog. So no need to go with something nearly so complex as servo control. And the gearbox should limit jerky motion.

    The cost should be seriously cheap. Atary joystick, battery or wallwart, two gearbox motors, and four relays that are rated for the same voltage as the motors.


    and if the joystick switches are spdt, and your motor current requirements are low, you don't even need the relays.
  7. Wendy


    Mar 24, 2008