School Education New method and equipment for teaching digital logic computer organization to high-school students At the Computer Architecture and VLSI Design laboratory of the Institute of Computer Science of FORTH we are developing hands-on educational equipment and methodology for teaching Digital Logic and Computer Organization to High-School students. The Foundation for Research and Technology - Hellas (FORTH) is a leading public Research Center in Greece, operating under the Ministry of Development and Investments, and collaborating very closely with the University of Crete. Besides research and development work, FORTH has also been and is heavily involved in educational activities. With our 30-year background in designing simple hardware for high performance computing, and based on our 10-year experience in teaching digital design and computer organization to first-year students at the University of Crete using our own custom-made lab equipment, we are now developing novel hands-on hardware devices that we believe will be appropriate for teaching those same subjects to high-school students. The degree by which Computer Science and Engineering have now penetrated our lives requires that students be educated about computers since high or even elementary school. This education must include the basic notions of digital logic and how computers operate (computer organization), and this topic is our target. Our experience has shown that it may be better to teach these topics in a novel manner, different from the traditional way in which "Digital Design" is being taught, and this is what we want to try in this project. We believe that education should use "hand-on" methods as much as possible, and that guides us in what we do: same as in other sciences, like physics, it is very important for children and students to touch prototypes, play with them, and see how they operate. We want to do precisely that: create an educational laboratory space that school students will be visiting, and where they will perform themselves laboratory exercises under the guidance of researchers as well as their own teachers. FORTH already has a long experience in organizing visits by school classes to our research laboratories, of which we have been receiving many per year, for decades now. During these visits, students see demonstrations of systems and technologies, listen to presentations, have the opportunity to discuss with researchers, with the goal of understanding the applications of technology in modern life. In our Institute, we have also organized focused visits, e.g. on computer and internet safety, robotics, the history of computers, women in research, etc.
The new method and equipment or the last 10 years, at the Institute of Computer Science of FORTH, we have been building 3 generations of successively improved custom educational lab equipment, which we have been using at our closely-collaborating University of Crete for teaching Digital Design with an introduction to computer organization to first-year (Junior)
University students The corresponding first-semester course starts with simple switch logic: http://www.ics.forth.gr/~kateveni/120/11f/lab00_switches.html continues with relay logic: http://www.ics.forth.gr/~kateveni/120/11f/lab02_relays.html#dec3r and with chips-based circuits, and culminates with an educational board: http://www.ics.forth.gr/~kateveni/120/11f/lab11_dpath.html#lab_proc that displays all address and data values in the datapath of a very simple processor,allows students to activate control signals by first pushing switches, and then to build the control section of the processor using their own chips so as toenable this computer to execute real programs.
Our experience during these 10 years has shown to us that the fundamental concepts of "how computers are built" are simple enough to be taught to high-school students (and could even start from elementary school), and that is what we now want to develop. We have recently strarted developing a new generation of educational boards and kits for this purpose, based on a novel concept. The new concept on which we base this generation of educational lab equipment relies on our observation, during the last 10 years, that the concept of Random Access Memory (RAM) is: (a) of central importance, (b) not immediately obvious to a teenager, and (c) easy to explain if one starts with crossbar-shaped wires with jumpers (and diodes) at the crosspoints that store a "1" value. The junior students in our University class required considerable effort in order to grasp the concepts of: (encoded) addresses, (decoded) word-lines, data words as memory contents, and bit-lines. In turn, these concepts of addresses versus data are of central importance to all of computer science and programming. Also, notice that a Read-Only Memory (ROM), which is the first step towards a RAM, is in fact the truth table of an arbitrary combinational circuit. Thus, instead of starting to teach digital design in the traditional way using AND - OR - NOT gates, we now want to experiment teaching it to high-school students in this novel way, teaching the folowing two concepts first: (1) crossbar-shaped wires form a ROM - use this ROM to control a 7-segment display; and (2) a binary tree of relay switches forms a decoder - use it to decode an arbitrary user code that drives the ROM, then displaying the desired decoded message (this is the introduction to address decoding). We are planning for three pieces of equipment: (a) a board for familiarizing the student with electric circuits; (b) a crossbar-ROM; and (c) a device that emulates a programmable ROM or a RAM and allows the student to build larger systems - even a simple processor. We have built a prototype of (a) and one of (b), and we are now developing a prototype of (c). (a) (b) The crossbar ROM (b), is better described, with related photographs, here.
