microcontroller and then read the pin
as you would any switch closure.
• PC joysticks use potentiometers to
proportionally measure the position of
the joystick. There are a variety of ways
of interfacing these to a microcontroller,
including via an analog-to-digital input
pin (if the controller is so equipped),
through a resistor and capacitor (a
simple form of go/no-go analog measurement), or a 555 timer where the
position of the potentiometer changes
the pulse width and/or duration of
the timer output. All three of these
techniques are fairly well documented
on a number of websites; use Google
or Yahoo to search for “IBM PC joystick interface” (without the quotes).
Abacom Technologies offers transmitters, antennas, and everything
in-between for radio communications.
• An Atari style joystick is a simple
switch contact controller. These are
among the easiest to interface to your
robot. Push the joystick up and the Up
switch closes. Push it to the left and
the Left switch closes. You connect
the wires for each switch to a
separate input pin on your robot’s
Lemos International specializes in Bluetooth, ZigBee, and RF data modems,
with numerous products in each category.
• Playstation remotes use a controller
for the Sony Playstation 2. You may use
wired or wireless controllers. The
controller outputs a complex digital
datastream that needs to be decoded
using a microcontroller. Lynxmotion sells
a low-cost adapter cable for the PS2
remote, so you don’t have to cut off the
connector and solder the wires directly.
They also provide a programming tutorial on interfacing the PS2 remote with
the popular Basic Atom microcontroller.
In addition to the sources listed
below, check out online and local hobby
store retailers that specialize in radio
control model airplanes and cars, where
you can find numerous transmitter/
receiver packages for operating R/C
servo motors via radio remote control.
Full resource of wireless
including data modules (receivers,
transmitters, transceivers), antennas,
RF remote control, and more.
Official Bluetooth technology
resource page. Includes several
technical papers for downloading.
64 SERVO 08.2008