Page 59 - The Definitive Guide to Building Java Robots

Preston_5564C02.fm Page 40 Wednesday, September 14, 2005 5:42 AM

40 CHAPTER 2 ■ SERIAL COMMUNICATION

public static void main(String[] args) {
try {
StampSerialTest sst = new StampSerialTest();
System.out.println("From Stamp:" + sst.test((byte)101));
System.out.println("From Stamp:" + sst.test((byte)102));
} catch (Exception e) {
e.printStackTrace();
System.exit(1);
}
System.out.println("Done.");
}

}

Section Summary
The Stamp program and Java class created in this section were

• SerialEcho.bs2: This program resides in the microcontroller and will echo an “a” and “b”
depending on the commands sent to the controller.

• StampSerialTest.java: This class is designed to send and receive specific information to
the microcontroller on coordination with SerialEcho.bs2.
Once you have tested basic access to your microcontroller, now it’s time to extend on this
concept a bit and model your microcontroller, first by creating a generic one that can be used
for any type of microcontroller, and then by creating a version that corresponds precisely to
your Stamp program.

2.5 Modeling a Microcontroller with Java

While I could use the StandardSerialPort to send and receive data to and from a robot, this
makes it more difficult down the road as the robot’s capability increases. So, to begin you will
need a microcontroller. I choose the Parallax BASIC Stamp because it’s easy to program and
there are lots of examples and support available for this model.
The first Parallax BASIC Stamp comes in nine different versions, not including the OEM
versions. They come with 8, 16, and 32 I/O pins that operate from 4MHz to 50MHz and can be
programmed with up to 12,000 instructions. They are quite versatile and there are plenty of
examples of software on the Internet, as well as those provided from the manufacturer’s web
site at www.parallax.com.
The two pictured in Figure 2-6 and Figure 2-7 are the BASIC Stamp 2 and the Javelin Stamp.
The Javelin Stamp is the Java version. You can find all the program examples in this book for
the Javelin Stamp in Appendix 2. All other examples will be for the BASIC Stamp 2 since it’s the
most popular and, as I said earlier, there are more examples for this microcontroller at present.