A Controller For Robotics And Microcontroller Applications Instruction

Abstract

A controller board inspired by the Handy Board, but based on a pair of Atmel ATmega128’s, is discussed. Elements of the hardware design and input/output interfaces are detailed, including parallel and serial I/O, analog I/O, an LCD interface, and dc motor control interfaces. Firmware for hardware drivers written in AVR assembly language and a handshaking protocol for communications between the microcontrollers are also discussed.

The new controller board, designated Koios I, will first be used in our freshman introductory course – in lieu of the Handy Board – which involves learning about electrical and computer engineering through the design and control of robots. Koios I will also be used in our microcontrollers application course, in our senior capstone design course, and in independent research courses requiring a dedicated computer/controller.

Like the Handy Board, Koios I is being developed in an open-source manner. Schematics and firmware code listings are readily available on the web. The firmware for Koios I is written in AVR assembly language; however, user applications can be written in either assembly language or the C programming language via an AVR port of the open source C complier gcc.

Printed-circuit board layouts using surface mount devices are currently in progress; the results of which will be made available in the same manner as the schematics and code. Koios I is intended to be continually evolving and a USB interface for program download and an integrated development environment are planned for the near future.

Microcontrollers are found in the implementations of solutions to problems in many sub- disciplines of electrical and computer engineering as well as other fields of engineering and science. In deed, the applications of microcontrollers are taught in a variety of courses: electrical and computer engineering—microcontrollers and microprocessors, mechanical engineering—mechatronics, physics—instrumentation, and chemistry—process control. Within an ECE curriculum, microcontrollers can be applied in digital and computer courses, introductory courses, signal processing and controls courses, robotics courses and capstone design courses. Parten1 emphasizes the importance of microprocessor education to ECE students that first take a formal course on microprocessors followed by a design projects course where the focus is the application of microprocessors in embedded systems. Microcontrollers also find their way into various robotics courses2 and design contests such as the Trinity Firefighting Home Robot Contests3 and the IEEE Region 3 Student Hardware Contest4.

To serve this variety of applications, a microcontroller is best incorporated into a board that is flexible, provides a variety of interfaces, and is easy to employ. Fred Martin realized the value of such a board when he developed the Handy Board5, 6 as an outgrowth of the controller used