I have been playing with a Arduino microcontroller and robotics bits and pieces for a while now.
I'm still designing my first robot and wanted a two-way wireless capability, but until now they were either too expensive , or too basic .
BUT NOW I HAVE THE SOLUTION: The Pololu Wixel programable USB wireless module!
It comes in a variety of packages, the one I chose was the assembled combination deal, http://www.pololu.com/catalog/product/1338 (picture two ), which has a pair of modules and a mini USB cable for $42 USD + shipping. Or you can get a single module either assembled (with breadboard pins) or not for $21 or $20 (pictures three & four ).
So what can it do you ask?
Well to quote Pololu:
"The Pololu Wixel is a general-purpose programmable module featuring a 2.4 GHz radio and USB. The Wixel is based on the CC2511F32 microcontroller from Texas Instruments, which has an integrated radio transceiver, 32 KB of flash memory, 4 KB of RAM, and a full-speed USB interface. A total of 15 general-purpose I/O lines are available, including 6 analog inputs "
there are very flexible fancy uses, but for starters simply download one of six (and growing) precompiled, open-source 'apps';
a. Blink an LED (Wow you say sarcasticly ! - this is just an example/test app),
b. Wireless Serial, a bidirectional lossless serial link, either end can be USB, or UART,
c. USB to TTL Serial adapter (@ 3.3V), no need to get a FTDI cable/converter,
d. I/O Repeater, wirelessly send/receive up to 15 microcontroller I/O pin states,
e. Wireless ShiftBrite RGB LED control (http://www.pololu.com/catalog/product/1240) ,
f. Wireless tilt mouse, using an 3-axis accelerometer.
Details of these apps can be found at http://www.pololu.com/docs/0J46/9 .
There is also much more it can do, including a SDK, which I will mention in a later step.
You should note now its main flaw; IT IS NOT 5V I/O TOLLERANT (Argh!). However this is easily managed, but be carefull connecting it on 5V projects or you'll fry a pin. You have been WARNED!
The other flaw is that when on the breadboard you can't see the pinouts, they are on the bottom! They could have used longer pins, to clear the USB connector, on the opposite side, thus breadboardable with the pinouts facing up. Version 2 Mr Pololu? You could buy the unassembled version and get some longer header pins.
Next - What you need.
(some images courtesy of Pololu)
Step 1: What else do you need?
Of course you don't need a Wixel to proceed, this instructable will introduce you to most of the capabilities of a Wixel.
As I mentioned I have been learning the Arduino so I will be focusing on this platform, you could use Wixels with other microcontrollers, or just use the built-in TI CC2511F32 microcontroller, but I don't want to learn a new platform just now.
So you will need an Arduino or compatible microcontroller for the more complex examples. I have a Duemilanove, but a new Uno is good, or you can get cheap bare bones kits, just search instructables for 'Arduino' and you will see lots of options. See http://www.arduino.cc/ if you are unfamillier with this platform.
Note: This is not an Introduction to Arduino, again search and you will find many 'ables to help you out.
For the examples in the following steps you will need;
2 x Wixels, http://www.pololu.com/catalog/product/1336 ,
1 x USB A to Mini-B cable or adapters, http://www.pololu.com/catalog/product/130 ,
(or the Combo Deal http://www.pololu.com/catalog/product/1338 )
1 x Arduino microcontroller, with USB cable or programmer/FTDI cable to suit, http://www.pololu.com/catalog/product/1616
1 x Windows PC/Notebook with two USB ports (with Arduino software installed),
2 x Medium Prototyping breadboards (270+ points, but I'd get 400 points), http://www.pololu.com/catalog/category/28 ,
Various prototyping wires such as
(http://www.pololu.com/catalog/category/29 and/or http://www.pololu.com/catalog/category/68 ),
4 x AA batteries, either normal 1.5V AA, or rechargable 1.2V AA (http://www.pololu.com/catalog/product/1003 ),
1 x Four AA battery pack, with bare wires for breadboard connection,
This one has a switch built in http://www.pololu.com/catalog/product/1159
I have one without a switch, so I used this http://www.sparkfun.com/products/102 ,
(or a breadboard connectable 5V regulated DC source).
1 x 1.2k Ohm resisters,
1 x 2.2k Ohm resisters,
(If you're just starting & don't have resisters I recommend this kit http://www.sparkfun.com/products/9258, or get individual packs at http://www.futurlec.com/Res14W.shtml )
2 x Momentory pushbutton micro switches, http://www.pololu.com/catalog/product/1400 ,
4 x LEDs, any will do but two colours will look better, (http://www.pololu.com/catalog/product/1070 & http://www.pololu.com/catalog/product/1071 ),
Optional - only get these if you have another use for them:
1 x PIR Motion Sensor,
(or any which can run on 3.3V and has a digital out pin, Pololu have this one http://www.pololu.com/catalog/product/1635 but you will need to follow their instructions to run at 3.3V)
1 x 3 Pin male headers, http://www.pololu.com/catalog/product/965 & a pair of pliers to save the ouch factor.
Naturally if you're experienced, use whatever you have at hand.
In the next steps I will start with simple uses and expand to more complex examples.
Next - Setup the Wixels.
[Note: I have linked to Pololu above for simplicity, many of these components are also available elsewhere, use your favourite sources. I have no connection with Pololu apart from liking their products. (but happy to get any free samples though, Mr Pololu... ;). Ditto for Sparkfun, DFRobot, Littlebird and Futurlec etc.]