Slashdot Mirror

WCityMike asks: "What is the origin of the cost of bandwidth? For instance, if I'm being charged for an apple, I know that, theoretically, the cost of that apple is going towards the purchase of apple seeds, the land on which the apple trees are grown, the fertilizer and water that helps the trees grow, and the salaries of those who pick the apples, clean them, box them, and send them to market. When an Internet provider charges someone hundreds of dollars in bandwidth costs because they were Slashdotted (or Farked) and their bandwidth use shot up, what costs have the Internet provider incurred, and why does it cost them what it does? Is there usually any sort of markup going on along the line, or are people just passing along their own expenses down the line to the end user?" It would be interesting to note the most important factor contributing to bandwidth costs. How much of the total costs are tied to infrastructure versus the human component (technicians, sysadmins, technical support and so forth)?

WCityMike writes "Blogger has been severely hacked into, with users' passwords and e-mail addresses being replaced with 'hacx0redbyme' or 'hax0redbyme.' Apparently, attempts to change your password or other information do not succeed due to a major database problem. Blogger currently has no official news: its main page simply apologizes for being down for repairs and its status blog has no information, probably suffering from the same accessing problem as other blogs. In the meantime, discussion, information, and advice is appearing on the weblogs of Anil Dash and Tom Coates, as well as this QuickTopic thread. Glad I use another journaling service." We usually try to avoid "Site X Hacked!" stories, but since this affects so many people - and, heh-heh, they don't have anywhere else to talk about it - here you go.

WCityMike writes "One of the programmers at Unsanity, maker of haxies, recently posted a rather shocking relevation on the company's weblog. He says that Mac OS X's Mach-O runtime ABI (Application Binary Interface) comes from a NeXTStep design for 68K processorts, and is not designed for the PowerPC architechture. Had they used the latter, things would have been approximately 10-12 percent faster. And supposedly, they can't fix it now without breaking all existing applications." The developer mentions there are workarounds in the newest GCC, but only for newly compiled programs.

WCityMike writes "This switch document for developers details the interface differences between Microsoft Windows and the Aqua interface used in Mac OS X. Written on a layman's level, it actually makes for pretty interesting reading!"

WCityMike writes "Amazon has quietly revoked the $50 rebate for Mac OS X 10.2 it was supposedly offering through September 3. The rebate form was updated to reflect this a few hours later. While theories as to why abound (including supposed involvement from Apple), some have reasonably pointed out that Amazon may not have expected as voluminous a response as they got, making the rebate a potentially major cash loss had it continued at that volume. People who already placed their orders should probably contact Amazon, while the rest of us can simply continue hoping Apple will offer its own 'rebate'." I think maybe it was a mistake; the rebate form I saw originally never had Mac OS X 10.2 on it.

WCityMike writes "Apple's decision to offer no upgrade fee to existing Mac OS X users caused a great deal of unrest amidst Macintosh users, but Amazon may have made the argument a bit moot by offering a $50 mail-in rebate, thus bringing the price down to $79 for all users. Check out their listing for 10.2, or the mail-in rebate form. I wonder if, when Apple notices all its orders are coming in through Amazon, they'll get the point?"

evilandi writes: "Spacewar, the world's first arcade game, is 40 years old this summer. Read this article at the BBC and play Spacewar using a Java emulator- remember, this was a two-player only game, designed in 1961 when programmers had friends who were in the same room! Spacewar, which was similar to Asteroids, later shipped as standard software for the PDP-1." Well, maybe the first electronic arcade game ;) -- or can anyone cite counterexamples?

Kzip sent us an interesting paper on script kiddies. It basically follows a log of a box being cracked and rooted, and then has tons of IRC logs with the responsible folks. A lot of insight into the mentality, but more important, the novice skill level required to do serious damage to many systems.

jhines sent us a nifty bit over at Wired about a Web design contest.. . the catch is the 5k maximum. The prize? 5120 cents ;) I won't enter: the best I could do was Slashdot's Light Mode.

Quite a number of you out there are into Lego Mindstorms, as evidenced by the number of book reviews that have been sent my way. Below are a couple of reviews, one from Kurt DeMaagd and the other from Will Ware. Click below to get their take on the O'Reilly book The Unofficial Guide to Lego Mindstorms Robots. The Unofficial Guide to Lego Mindstorms Robots author Jonathan B. Knudsen pages 247 publisher O'Reilly & Associates rating 9/10 reviewer Will Ware & Kurt DeMaagd ISBN 1-56592-692-7 summary Get the most out of your Lego Mindstorms The Unofficial Guide to Lego Mindstorms Robots Review by Will Ware

Last year, Lego released their Mindstorms Robotics Invention System. Using this, children and adults can build simple robots whose behavior can be programmed. The Mindstorms system is a major contender for Coolest Toy on the Planet.

The system contains a RCX programmable brick containing an H8/300 microcontroller, some pushbuttons, a little LCD display, and connectors for motors and sensors (light and physical contact). The user writes a program using a graphical programming language on his Windows box, and downloads it to the RCX via infrared.

Not surprisingly, substantial reverse engineering (1, 2) has been done by hobbyists, and it is possible to develop Mindstorms programs on a Linux box and to download the RCX brick from Linux.

Now O'Reilly has joined the Mindstorms fray, with a book full of fun and useful information about how to build and program Mindstorms robots. The book describes four different robots: Hank is a bumper car robot, Trusty uses light sensors to follow a line along the floor, Minerva has a movable arm, and two identical robots play a game called RoboTag. Along the way, the author discusses the physics and mechanics of robots, programming issues, and the available development environments for Mindstorms.

What's Good? There are detailed building instructions for each of the robots, showing photos at various stages of construction. The designs are simple and appear mechanically sound. There are discussion of the physics and mechanics of tank treads, steering, gears, and other things.

The book's chapters sequentially step through several different software development environments. The first chapter starts with the Windows-based RIS environment that comes on the Mindstorms CDROM. Later chapters give programming examples for NQC (Not Quite C), pbFORTH, Visual Basic, and the legOS operating system, which uses an EGCS cross-compiler to target the H8/300. There are more development platforms available, but these give a good sense of what's possible in Mindstorms programming.

The book has dozens of useful URLs, for both official Mindstorm sites and unofficial hobbyist sites. I particularly liked the fact that the author was aware of some of the recent research in robotics. For instance there is some discussion of Rodney Brooks' subsumption architecture, which is used for the RoboTag robots.

Later chapters of the book often expand on designs from earlier chapters, building more sophistocated robots in an accessible, incremental fashion. For the more adventurous hobbyist, the final chapter talks about building your own sensors and actuators, and how to connect them to the RCX.

What's Bad? Some of the photos are too dark and lack contrast. It would also have been nice if the photography had been in color, but black-and-white photos kept the book more affordable.

This book is for the casual weekend robot-building tinkerer, and it never promised to discuss real-time embedded issues in depth. Still, a few topics might have merited at least brief mention. Systems with real-time multitasking must frequently arrange for synchronization and communication between tasks, using mutexes and mailboxes and the like, which brings the possibility of deadlocked processes. Another danger is that an aggressively efficient compiler will sometimes optimize away reads and writes to hardware registers. The fix is to declare such registers with the volatile keyword.

Review by Kurt DeMaagd

While Lego Mindstorms were officially released for a teenage crowd, they have become popular with a wide variety of technically competent people in many age groups. This widespread fascination has opened up a whole new world of opportunities for using Mindstorms. At the same time, the documentation and tutorial included with the Lego kits provide very little information about how to get the most out of the sets. This book fills the void by providing several start-to-finish robot designs, software to run them, and a wealth of other tips and tricks.

After a brief introduction to robotics and how Legos fit in, the author discusses the basics of using Mindstorms to create them. Both chapters present a problem, provide step by step building instructions, provide the necessary information to program the solution, and finally go into greater detail about the Lego features used to solve the particular problem.

While the chapters did an excellent job of presenting this information in general, they fell victim to a problem that would plague the entire book: some of the building diagrams were nigh unto unreadable. Attempting to build a robot based on fuzzy black and white photographs can be quite a chore. Fortunately, none of the robots were so complex that they robots were completely unbuildable.

The first few chapters presented robots programmed with the default RIS programming environment. In chapter four and following, he shows how to program using languages such as Not Quite C, Forth, Sprit.ocx for Visual Basic--or optionally Visual C++ or another ActiveX-aware language--and legOS. Since much of these sections was documenting API's, it was certainly not the most exciting read, but it does provide concise, easily to reference documentation.

Not Quite C, as the name implies, is a C-like language that can be used to program Mindstorms robots. It overcomes many of the limitations of the default RIS programming environment, most notably the lack of variables. One of its biggest advantages is that it does not require the user to install a new version of the firmware on their RCX unit. In general, it provides an excellent balance between power and usability.

The remaining three means of programming presented in the book are fairly mediocre options. PbForth requires the user to download a new firmware version, and the language itself is very archaic in modern software development terms. Using Sprit.ocx is a viable option for people used to programming in Visual Basic or Visual C++, but the control structures are very clunky and non-intuitive. legOS, while it is probably the most powerful option, takes a significant amount of time to set up and develop applications with.

Two of the projects referenced while discussing the various programming languages were particularly interesting, both of which outlined infrared communication. The first program creates a simple remote control for controlling a robot via the IR port on the RCX. The other example, perhaps the most interesting in the book, was creating two robots who played tag with each other. These two robots also communicated with each other via their IR ports.

The last chapter, targetted toward the hard core Mindstorms users outlined how to create additional sensors for Mindstorms. It sketched out such possibilities as a passive light sensor, a Hall effect sensor (magnetic fields), and a touch multiplexor (allowing you to have more touch sensors than normally allowed on the RCS unit).

In general, the book provides a vast array building and programming tips, tricks, and methods. He gives basic information for the person who is just starting, and introduces the advanced user to the vast network of people and product that have made Mindstorms far more than a child's toy.

Purchase this book at fatbrain.

Table of Contents

• Preface

• 1. Welcome to MINDSTORMS
• What is a Robot?
• Mobile Robots
• What is MINDSTORMS?
• What Now?
• Online Resources

• 2. Hank, the Bumper Tank
• About the Building Instructions
• Building Instructions
• A Simple Program
• Wheels
• Bumpers and Feelers
• Gears
• Multitasking
• Online Resources

• 3. Trusty, a Line Follower
• Building Instructions
• Some Tricky Programming
• The Light Sensor
• Idler Wheels
• Using Two Light Sensors
• Online Resources

• 4. Not Quite C
• A Quick Start
• RCX Software Architecture
• NQC Overview
• Trusty Revisited
• Online Resources

• 5. Minverva, a Robot with an Arms
• Building Instructions
• Programming
• Directional Transmission
• Pulleys
• Mechanical Design
• Two Sensors, One Input
• Where am I?
• Online Resources

• 6. PbFORTH
• Replacement Firmware
• pbForth Overview
• About Forth
• pbFORTH Words
• An Expensive Thermometer
• Minerva Revisited
• Debugging
• Online Resources

• 7. A Remote Control for Minerva
• Two Heads are Better Than One
• The Allure of Telerobotics
• Building Instructions
• Programming the Remote Control
• Programming Minerva
• Online Resources

• 8. Using Sprit.ocx with Visual Basic
• You May Already Have Visual Basic
• About Spirit.ocx
• Calling Spirit.ocx
• Immediate and Delayed Gratification
• Programs, Tasks, and Subroutines
• Tips
• Retrieveing the Datalog
• Online Resources

• 9. RoboTag, a Game for Two Robots
• Building Instructions
• Subsumption Architecture
• Online Resources

• 10. LegOS
• About legOS
• Development Tools
• Hello, legOS
• Function Reference
• New Brains for Hank
• Development Tips
• Online Resources

• 11. Make Your Own Sensors
• Mounting
• Passive Sensors
• Powered Sensors
• Touch Multiplexer
• Other Neat Ideas
• What About Actuators?
• Online Resources

• A. Finding Parts and Programming Environments

• B. A pbFORTH Downloader

• C. Future Directions

• Index

Quite a number of you out there are into Lego Mindstorms, as evidenced by the number of book reviews that have been sent my way. Below are a couple of reviews, one from Kurt DeMaagd and the other from Will Ware. Click below to get their take on the O'Reilly book The Unofficial Guide to Lego Mindstorms Robots. The Unofficial Guide to Lego Mindstorms Robots author Jonathan B. Knudsen pages 247 publisher O'Reilly & Associates rating 9/10 reviewer Will Ware & Kurt DeMaagd ISBN 1-56592-692-7 summary Get the most out of your Lego Mindstorms The Unofficial Guide to Lego Mindstorms Robots Review by Will Ware

Last year, Lego released their Mindstorms Robotics Invention System. Using this, children and adults can build simple robots whose behavior can be programmed. The Mindstorms system is a major contender for Coolest Toy on the Planet.

The system contains a RCX programmable brick containing an H8/300 microcontroller, some pushbuttons, a little LCD display, and connectors for motors and sensors (light and physical contact). The user writes a program using a graphical programming language on his Windows box, and downloads it to the RCX via infrared.

Not surprisingly, substantial reverse engineering (1, 2) has been done by hobbyists, and it is possible to develop Mindstorms programs on a Linux box and to download the RCX brick from Linux.

Now O'Reilly has joined the Mindstorms fray, with a book full of fun and useful information about how to build and program Mindstorms robots. The book describes four different robots: Hank is a bumper car robot, Trusty uses light sensors to follow a line along the floor, Minerva has a movable arm, and two identical robots play a game called RoboTag. Along the way, the author discusses the physics and mechanics of robots, programming issues, and the available development environments for Mindstorms.

What's Good? There are detailed building instructions for each of the robots, showing photos at various stages of construction. The designs are simple and appear mechanically sound. There are discussion of the physics and mechanics of tank treads, steering, gears, and other things.

The book's chapters sequentially step through several different software development environments. The first chapter starts with the Windows-based RIS environment that comes on the Mindstorms CDROM. Later chapters give programming examples for NQC (Not Quite C), pbFORTH, Visual Basic, and the legOS operating system, which uses an EGCS cross-compiler to target the H8/300. There are more development platforms available, but these give a good sense of what's possible in Mindstorms programming.

The book has dozens of useful URLs, for both official Mindstorm sites and unofficial hobbyist sites. I particularly liked the fact that the author was aware of some of the recent research in robotics. For instance there is some discussion of Rodney Brooks' subsumption architecture, which is used for the RoboTag robots.

Later chapters of the book often expand on designs from earlier chapters, building more sophistocated robots in an accessible, incremental fashion. For the more adventurous hobbyist, the final chapter talks about building your own sensors and actuators, and how to connect them to the RCX.

What's Bad? Some of the photos are too dark and lack contrast. It would also have been nice if the photography had been in color, but black-and-white photos kept the book more affordable.

This book is for the casual weekend robot-building tinkerer, and it never promised to discuss real-time embedded issues in depth. Still, a few topics might have merited at least brief mention. Systems with real-time multitasking must frequently arrange for synchronization and communication between tasks, using mutexes and mailboxes and the like, which brings the possibility of deadlocked processes. Another danger is that an aggressively efficient compiler will sometimes optimize away reads and writes to hardware registers. The fix is to declare such registers with the volatile keyword.

Review by Kurt DeMaagd

While Lego Mindstorms were officially released for a teenage crowd, they have become popular with a wide variety of technically competent people in many age groups. This widespread fascination has opened up a whole new world of opportunities for using Mindstorms. At the same time, the documentation and tutorial included with the Lego kits provide very little information about how to get the most out of the sets. This book fills the void by providing several start-to-finish robot designs, software to run them, and a wealth of other tips and tricks.

After a brief introduction to robotics and how Legos fit in, the author discusses the basics of using Mindstorms to create them. Both chapters present a problem, provide step by step building instructions, provide the necessary information to program the solution, and finally go into greater detail about the Lego features used to solve the particular problem.

While the chapters did an excellent job of presenting this information in general, they fell victim to a problem that would plague the entire book: some of the building diagrams were nigh unto unreadable. Attempting to build a robot based on fuzzy black and white photographs can be quite a chore. Fortunately, none of the robots were so complex that they robots were completely unbuildable.

The first few chapters presented robots programmed with the default RIS programming environment. In chapter four and following, he shows how to program using languages such as Not Quite C, Forth, Sprit.ocx for Visual Basic--or optionally Visual C++ or another ActiveX-aware language--and legOS. Since much of these sections was documenting API's, it was certainly not the most exciting read, but it does provide concise, easily to reference documentation.

Not Quite C, as the name implies, is a C-like language that can be used to program Mindstorms robots. It overcomes many of the limitations of the default RIS programming environment, most notably the lack of variables. One of its biggest advantages is that it does not require the user to install a new version of the firmware on their RCX unit. In general, it provides an excellent balance between power and usability.

The remaining three means of programming presented in the book are fairly mediocre options. PbForth requires the user to download a new firmware version, and the language itself is very archaic in modern software development terms. Using Sprit.ocx is a viable option for people used to programming in Visual Basic or Visual C++, but the control structures are very clunky and non-intuitive. legOS, while it is probably the most powerful option, takes a significant amount of time to set up and develop applications with.

Two of the projects referenced while discussing the various programming languages were particularly interesting, both of which outlined infrared communication. The first program creates a simple remote control for controlling a robot via the IR port on the RCX. The other example, perhaps the most interesting in the book, was creating two robots who played tag with each other. These two robots also communicated with each other via their IR ports.

The last chapter, targetted toward the hard core Mindstorms users outlined how to create additional sensors for Mindstorms. It sketched out such possibilities as a passive light sensor, a Hall effect sensor (magnetic fields), and a touch multiplexor (allowing you to have more touch sensors than normally allowed on the RCS unit).

In general, the book provides a vast array building and programming tips, tricks, and methods. He gives basic information for the person who is just starting, and introduces the advanced user to the vast network of people and product that have made Mindstorms far more than a child's toy.

Purchase this book at fatbrain.

Table of Contents

• Preface

• 1. Welcome to MINDSTORMS
• What is a Robot?
• Mobile Robots
• What is MINDSTORMS?
• What Now?
• Online Resources

• 2. Hank, the Bumper Tank
• About the Building Instructions
• Building Instructions
• A Simple Program
• Wheels
• Bumpers and Feelers
• Gears
• Multitasking
• Online Resources

• 3. Trusty, a Line Follower
• Building Instructions
• Some Tricky Programming
• The Light Sensor
• Idler Wheels
• Using Two Light Sensors
• Online Resources

• 4. Not Quite C
• A Quick Start
• RCX Software Architecture
• NQC Overview
• Trusty Revisited
• Online Resources

• 5. Minverva, a Robot with an Arms
• Building Instructions
• Programming
• Directional Transmission
• Pulleys
• Mechanical Design
• Two Sensors, One Input
• Where am I?
• Online Resources

• 6. PbFORTH
• Replacement Firmware
• pbForth Overview
• About Forth
• pbFORTH Words
• An Expensive Thermometer
• Minerva Revisited
• Debugging
• Online Resources

• 7. A Remote Control for Minerva
• Two Heads are Better Than One
• The Allure of Telerobotics
• Building Instructions
• Programming the Remote Control
• Programming Minerva
• Online Resources

• 8. Using Sprit.ocx with Visual Basic
• You May Already Have Visual Basic
• About Spirit.ocx
• Calling Spirit.ocx
• Immediate and Delayed Gratification
• Programs, Tasks, and Subroutines
• Tips
• Retrieveing the Datalog
• Online Resources

• 9. RoboTag, a Game for Two Robots
• Building Instructions
• Subsumption Architecture
• Online Resources

• 10. LegOS
• About legOS
• Development Tools
• Hello, legOS
• Function Reference
• New Brains for Hank
• Development Tips
• Online Resources

• 11. Make Your Own Sensors
• Mounting
• Passive Sensors
• Powered Sensors
• Touch Multiplexer
• Other Neat Ideas
• What About Actuators?
• Online Resources

• A. Finding Parts and Programming Environments

• B. A pbFORTH Downloader

• C. Future Directions

• Index

Quite a number of you out there are into Lego Mindstorms, as evidenced by the number of book reviews that have been sent my way. Below are a couple of reviews, one from Kurt DeMaagd and the other from Will Ware. Click below to get their take on the O'Reilly book The Unofficial Guide to Lego Mindstorms Robots. The Unofficial Guide to Lego Mindstorms Robots author Jonathan B. Knudsen pages 247 publisher O'Reilly & Associates rating 9/10 reviewer Will Ware & Kurt DeMaagd ISBN 1-56592-692-7 summary Get the most out of your Lego Mindstorms The Unofficial Guide to Lego Mindstorms Robots Review by Will Ware

Last year, Lego released their Mindstorms Robotics Invention System. Using this, children and adults can build simple robots whose behavior can be programmed. The Mindstorms system is a major contender for Coolest Toy on the Planet.

The system contains a RCX programmable brick containing an H8/300 microcontroller, some pushbuttons, a little LCD display, and connectors for motors and sensors (light and physical contact). The user writes a program using a graphical programming language on his Windows box, and downloads it to the RCX via infrared.

Not surprisingly, substantial reverse engineering (1, 2) has been done by hobbyists, and it is possible to develop Mindstorms programs on a Linux box and to download the RCX brick from Linux.

Now O'Reilly has joined the Mindstorms fray, with a book full of fun and useful information about how to build and program Mindstorms robots. The book describes four different robots: Hank is a bumper car robot, Trusty uses light sensors to follow a line along the floor, Minerva has a movable arm, and two identical robots play a game called RoboTag. Along the way, the author discusses the physics and mechanics of robots, programming issues, and the available development environments for Mindstorms.

What's Good? There are detailed building instructions for each of the robots, showing photos at various stages of construction. The designs are simple and appear mechanically sound. There are discussion of the physics and mechanics of tank treads, steering, gears, and other things.

The book's chapters sequentially step through several different software development environments. The first chapter starts with the Windows-based RIS environment that comes on the Mindstorms CDROM. Later chapters give programming examples for NQC (Not Quite C), pbFORTH, Visual Basic, and the legOS operating system, which uses an EGCS cross-compiler to target the H8/300. There are more development platforms available, but these give a good sense of what's possible in Mindstorms programming.

The book has dozens of useful URLs, for both official Mindstorm sites and unofficial hobbyist sites. I particularly liked the fact that the author was aware of some of the recent research in robotics. For instance there is some discussion of Rodney Brooks' subsumption architecture, which is used for the RoboTag robots.

Later chapters of the book often expand on designs from earlier chapters, building more sophistocated robots in an accessible, incremental fashion. For the more adventurous hobbyist, the final chapter talks about building your own sensors and actuators, and how to connect them to the RCX.

What's Bad? Some of the photos are too dark and lack contrast. It would also have been nice if the photography had been in color, but black-and-white photos kept the book more affordable.

This book is for the casual weekend robot-building tinkerer, and it never promised to discuss real-time embedded issues in depth. Still, a few topics might have merited at least brief mention. Systems with real-time multitasking must frequently arrange for synchronization and communication between tasks, using mutexes and mailboxes and the like, which brings the possibility of deadlocked processes. Another danger is that an aggressively efficient compiler will sometimes optimize away reads and writes to hardware registers. The fix is to declare such registers with the volatile keyword.

Review by Kurt DeMaagd

While Lego Mindstorms were officially released for a teenage crowd, they have become popular with a wide variety of technically competent people in many age groups. This widespread fascination has opened up a whole new world of opportunities for using Mindstorms. At the same time, the documentation and tutorial included with the Lego kits provide very little information about how to get the most out of the sets. This book fills the void by providing several start-to-finish robot designs, software to run them, and a wealth of other tips and tricks.

After a brief introduction to robotics and how Legos fit in, the author discusses the basics of using Mindstorms to create them. Both chapters present a problem, provide step by step building instructions, provide the necessary information to program the solution, and finally go into greater detail about the Lego features used to solve the particular problem.

While the chapters did an excellent job of presenting this information in general, they fell victim to a problem that would plague the entire book: some of the building diagrams were nigh unto unreadable. Attempting to build a robot based on fuzzy black and white photographs can be quite a chore. Fortunately, none of the robots were so complex that they robots were completely unbuildable.

The first few chapters presented robots programmed with the default RIS programming environment. In chapter four and following, he shows how to program using languages such as Not Quite C, Forth, Sprit.ocx for Visual Basic--or optionally Visual C++ or another ActiveX-aware language--and legOS. Since much of these sections was documenting API's, it was certainly not the most exciting read, but it does provide concise, easily to reference documentation.

Not Quite C, as the name implies, is a C-like language that can be used to program Mindstorms robots. It overcomes many of the limitations of the default RIS programming environment, most notably the lack of variables. One of its biggest advantages is that it does not require the user to install a new version of the firmware on their RCX unit. In general, it provides an excellent balance between power and usability.

The remaining three means of programming presented in the book are fairly mediocre options. PbForth requires the user to download a new firmware version, and the language itself is very archaic in modern software development terms. Using Sprit.ocx is a viable option for people used to programming in Visual Basic or Visual C++, but the control structures are very clunky and non-intuitive. legOS, while it is probably the most powerful option, takes a significant amount of time to set up and develop applications with.

Two of the projects referenced while discussing the various programming languages were particularly interesting, both of which outlined infrared communication. The first program creates a simple remote control for controlling a robot via the IR port on the RCX. The other example, perhaps the most interesting in the book, was creating two robots who played tag with each other. These two robots also communicated with each other via their IR ports.

The last chapter, targetted toward the hard core Mindstorms users outlined how to create additional sensors for Mindstorms. It sketched out such possibilities as a passive light sensor, a Hall effect sensor (magnetic fields), and a touch multiplexor (allowing you to have more touch sensors than normally allowed on the RCS unit).

In general, the book provides a vast array building and programming tips, tricks, and methods. He gives basic information for the person who is just starting, and introduces the advanced user to the vast network of people and product that have made Mindstorms far more than a child's toy.

Purchase this book at fatbrain.

Table of Contents

• Preface

• 1. Welcome to MINDSTORMS
• What is a Robot?
• Mobile Robots
• What is MINDSTORMS?
• What Now?
• Online Resources

• 2. Hank, the Bumper Tank
• About the Building Instructions
• Building Instructions
• A Simple Program
• Wheels
• Bumpers and Feelers
• Gears
• Multitasking
• Online Resources

• 3. Trusty, a Line Follower
• Building Instructions
• Some Tricky Programming
• The Light Sensor
• Idler Wheels
• Using Two Light Sensors
• Online Resources

• 4. Not Quite C
• A Quick Start
• RCX Software Architecture
• NQC Overview
• Trusty Revisited
• Online Resources

• 5. Minverva, a Robot with an Arms
• Building Instructions
• Programming
• Directional Transmission
• Pulleys
• Mechanical Design
• Two Sensors, One Input
• Where am I?
• Online Resources

• 6. PbFORTH
• Replacement Firmware
• pbForth Overview
• About Forth
• pbFORTH Words
• An Expensive Thermometer
• Minerva Revisited
• Debugging
• Online Resources

• 7. A Remote Control for Minerva
• Two Heads are Better Than One
• The Allure of Telerobotics
• Building Instructions
• Programming the Remote Control
• Programming Minerva
• Online Resources

• 8. Using Sprit.ocx with Visual Basic
• You May Already Have Visual Basic
• About Spirit.ocx
• Calling Spirit.ocx
• Immediate and Delayed Gratification
• Programs, Tasks, and Subroutines
• Tips
• Retrieveing the Datalog
• Online Resources

• 9. RoboTag, a Game for Two Robots
• Building Instructions
• Subsumption Architecture
• Online Resources

• 10. LegOS
• About legOS
• Development Tools
• Hello, legOS
• Function Reference
• New Brains for Hank
• Development Tips
• Online Resources

• 11. Make Your Own Sensors
• Mounting
• Passive Sensors
• Powered Sensors
• Touch Multiplexer
• Other Neat Ideas
• What About Actuators?
• Online Resources

• A. Finding Parts and Programming Environments

• B. A pbFORTH Downloader

• C. Future Directions

• Index

Derek Glidden writes "Not Quite C is a C-like programming language for programing the Lego RCX brick that runs on Linux! This sort of programming is a lot easier than the funky visual interface Lego supplies. (Plus, did I mention it runs on Linux?)" amazing what ya stumble on over at FreshMeat, isn't it?