simple devices after reading this book.
The Arduino USB board uses an ATMega328. This is a
powerful chip processor that runs at 20 MHz. This is the
same speed as the BASIC Stamp II module we talked about
earlier and is only a fraction of the cost. It can hold more
lines of code than you’ll need in almost all cases, and
provides a high level of efficiency for a very reasonable
price.
There are a few choices with the Arduino and,
depending on the size of your project, you’ll need to make
some tough decisions. The most popular is the Arduino
Duemilanove (the one that has the ATMega328) and it
costs about $30. Power users will want to consider the
Arduino Mega with more I/0 pins for about $65. There is
also the Arduino mini (about $20), and the Arduino nano
($30-$60).
You can code the Arduino in a variety of languages,
though one of the most popular is Processing; it is based
on Java. Processing is easy to interface with hardware and
is no harder to learn than Basic (many think it’s easier).
The Arduino recap:
Pros:
- Low cost, very popular, lots of documentation, easy to
learn, good programming language, variety of shields
available.
Cons:
- There really aren’t low cost boards like the PICAXE $4
protoboard. However, this is not a problem since most
projects will call for a larger chip than an eight-pin variety.
Summary and Recommendation
Now that we’ve covered three of the main
microcontrollers, here’s what I would recommend. For small
projects and to just get started in basic microcontroller
usage, use the PICAXE 08 or 18-pin. For simple robots, use
a PICAXE board with the built-in motor driver. For all other
projects — especially those that are more complex or
someday will need more capability and flexibility — give
strong consideration to the Arduino family of products. SV
66 SERVO 03.2010