Radio Shack Mobile Robot manual Coprocessor Network Expansion, Communications

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Coprocessor Network Expansion

The complete application note for coprocessor expansion can be found on our website at:

www.robotics.com/arobot/projects.html

A coprocessor is one of the most powerful expansions that can be added to ARobot. A coprocessor can remove time consuming tasks from the master processor, leaving it for higher level routines. The coprocessor could be used to add a ring of sonar range finders, read a time consuming compass, proc- ess video images, control motors, etc. Any microprocessor, embedded PC, or computer can be used as a coprocessor. A Basic Stamp II is an excellent choice because it doesn’t need any external circuitry to communicate with ARobot’s controller. The Basic Stamp II can also be programmed by plugging it into ARobot’s controller which eliminates the need for a programmer.

Communications

ARobot’s controller can communicate in a serial fashion with the coprocessor using the dedicated co- processor network pin (P8 on the Basic Stamp) or by using any other unused pin(s). A program on the coprocessor will receive commands from the master (ARobot’s controller) and respond accordingly. Review the coprocessor command summary to see how commands must be constructed to prevent communication conflicts.

Basic Stamp II Coprocessor

Multiple Basic Stamp II Coprocessors

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Contents Assembly and User Guide ARobot Mobile Robot Connectors Introduction About ARobotBasic Stamp II Control Computer What You’ll Need Feature ListTechnical Specifications Precautions Controller Component LocatorGlossary of Terms Glossary of Terms Glossary of Terms Assembly Overview Parts Quantity Description Used ForAbout Screw, nut, and washer sizes Parts Motor Brackets Sanding PaintingPaint Primer Finish CoatWhiskers SummaryHow it Works Whisker Detail Full Scale Whisker Wire Pattern Drive Motor and Brackets Encoder Sensor Front Wheel Assembly Steering Motor and Rear Wheels Steering Motor Mounting Wheel and Axle Steering System Controller Board Battery Pack Don’t install batteries yetSummary Don’t install batteries yet Body Cable Finishing Up Basic Stamp II Installation About the Controller BoardProgramming PC Editor/Downloader Software Cable to your PCUSB Port Programming NotePrograms Steering Adjustment Program STRAIGHT.BS2Test Program TEST.BS2 Wander Program WANDER.BS2About the Controller Board Power On/Off Switch Reset ButtonBatteries Speaker LED indicatorsDrive Motor and Encoder Push Buttons and Jumpers switchesSteering Motor Example !1M11200E7 Coprocessor Command SummaryCoprocessor Communication Rules RC Servo Motor and Steering Motor ControlHexadecimal, Binary, Bytes, Words, etc Body Connector J8 Battery Connector J9Serial Port J12 PinoutDrive Motor Connector J10 RC Servo Motor Connectors J2-J5Powerful Connector J11 Voltage 12 volts Maximum Current 500ma PinoutExpansion Port RC Servo Motor Signals Expansion Connector J1Expansion Port Circuit Examples Digital/Power Output Switch Input ExampleDigital Inputs Sensor Input ExampleBasic Stamp II light sensor example code Analog InputsCommunications Coprocessor Network ExpansionUsing Other Controllers Using ARobot’s controller as a coprocessorCabling between ARobot’s controller and another controller Suggested Reading Component Suppliers Small Parts Sava IndustriesStock Drive Products SuperCircuitsWeb Sites Internet Robot ResourcesNewsgroup NameDescription Internet News GroupsTroubleshooting Arrick Robotics Warranty InformationRobotics.com