Pbforth; Replacement Firmware; Pbforth Overview; About Forth - LEGO MINDSTORMS Robots Manual

http://www.sonic.net/~rci/transmission.htm
This page, created by Michael Powell, describes the basic principle of the directional transmission with detailed photographs.
Ben's Lego Creations
http://www.pobox.com/~benw/lego/
This page contains some fascinating robots created by Ben Williamson. A modified version of Ben's FetchBot arm was used as Minerva's grabber arm. These robots are mechanically superlative;
check them out.
"Where am I?"—Systems and Methods for Mobile Robot Positioning
http://www-personal.engin.umich.edu/~johannb/position.htm
Johann Borenstein's book about mobile robot navigation can be downloaded from this site as an Adobe Acrobat PDF file. The whole book is 13 Mb, which is a little hefty for my dial-up Internet
connection, but a free book is a free book. It's gotten good reviews from the MINDSTORMS online community.
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pbFORTH

In this chapter:

• Replacement Firmware

• pbFORTH Overview

• About Forth

• pbFORTH Words

• An Expensive Thermometer

• Minerva Revisited

• Debugging

• Online Resources

In Chapter 4, Not Quite C, I described how NQC allows you to get around many of the limitations of RCX Code, the programming environment that comes with RIS. Even NQC, however, has its
limitations. Even though you finally have the use of variables, you're limited to 31 of them. Furthermore, you can't put your own data on the display, which would be very useful for debugging. In
this chapter, I'll talk about pbFORTH (Programmable Brick Forth), a piece of software that gives greater access to the memory, display, and other resources in the RCX. pbFORTH allows you to
program your robots using Forth, an established language that is suitable for small systems like the RCX.
This chapter will get you up and running with pbFORTH by covering the following topics:
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