Mobile Robots Teach Machine-Level Programming

We feel strongly that a contemporary introductory course in machine organization and assembly language should focus on the essentials of how computers execute programs, and not be distracted by the complications of the extraordinarily sophisticated microprocessors that are available today. These essentials should form a strong base of knowledge from which students can draw as they continue their education in computer science. Ideally these goals should be attained in an environment that fosters experimentation and cooperation, and with the aid of projects that generate interest and enthusiasm among the students. We have developed and are currently teaching a course at New Mexico State University that meets many of these goals. The course concentrates on a simple but relatively complete microprocessor architecture, that of the Motorola 68HC11 processor. Three different teaching techniques are used to encourage experimentation and team work: learning sessions, simulator labs, and microprocessor labs. New concepts are introduced in learning sessions, which combine traditional lecturing with student exploration. The understanding of these new concepts is strengthened through labs and assignments. Simulator labs and assignments, which require interaction with a simulator of the Motorola 68HC11 microprocessor, focus on the 68HC11's instruction set architecture. Microprocessor labs and assignments, which essentially are designing and building sessions, focus on the use of a 68HC11 microprocessor to control a motorized vehicle. During microprocessor labs students populate printed circuit cards, build motorized vehicles (or other roboticized exotica), and design and implement assembly language programs that provide communication between a personal computer and a 68HC11 processor, and a 68HC11 processor and a motorized vehicle. We have found that the costs of running this course are minimal and the results are very favorable in terms of student enthusiasm and achievement.