A low-cost development platform to design digital circuits on FPGAs using open-source software and hardware tools

Abstract

The practical implementation of digital systems during the lab sessions of an undergraduate digital electronics course can be done using monolithic integrated circuits such as the TTL 7400 or CMOS 4000 series and breadboard wires to connect them into a protoboard, or using reconfigurable hardware devices such as the FPGAs. In the first approach, many students face difficulties in the wiring and testing processes due to the large number of wired connections that must be carried out, while in the second approach difficulties arise with the limited or restricted access that students have in order to use the software and hardware development tools needed to program the FPGAs. Frequently, in many schools of engineering and faculties, these tools are only available during the lab sessions and, after finishing each session, they are usually stored with no free access to them. Thus, students cannot practice freely to improve their digital electronics knowledge and skills. In order to try to overcome both problems, this work presents a low-cost development platform to design digital circuits on FPGAs that: 1) is easily replicable, 2) the number of wired connections is minimized, and 3) is based on the use of open-source software and hardware tools. Using such approach, students are able to work at home on the lab exercises before coming to the lab. Thus, during the lab sessions they can deepen the fundamental aspects of digital electronics instead of being focused on solving wiring mistakes.