Electrical & Computer Engineering Classroom Innovations

First Experiences with the AVR ATmega32 Microcontroller



In the fall of 2013, the Electrical Engineering department at ** institution omitted ** reconfigured its microcontroller instructional laboratory to use the AVR ATmega32 microcontroller from Atmel for the first time. This change was prompted by pressure from students, who displayed considerable interest in the AVR family of processors due to its use in popular Arduino microcomputer systems. In response to this expressed interest from students, the microcontroller lab was redesigned around this new processor. Atmel’s ATmega32 is an 8-bit RISC processor, based on Harvard architecture. This new hardware replaced systems using Freescale’s S12 processor, which is a 16-bit CISC processor, based on Princeton architecture. Thus, this change was a fundamental shift on at least three axes of computer characteristics. Was this change a gain or a loss on each of those three axes? Experience this year with teaching the lab using the ATmega32 has been generally positive, and this paper reports that experience in making the switch from the S12 to the ATmega32. Despite the fundamental architectural differences between the former processor (S12) and the new processor (ATmega32), there are many similarities between the processors as well. The hardware features of the ATmega32 mimic the S12’s features almost exactly, although the ATmega32 generally contains less of each feature, such as memory, I/O ports, timing features, etc. Many of the resources of the S12 were unused and wasted in lab exercises in the past. The scaled-back ATmega32, with basically the same features but in less abundance, is a better match to the instructional needs of this lab. Students feel they are getting a more complete exposure to the ATmega32, since nearly all the resources of the processor have been used in lab exercises, whereas many of the resources of the S12 were ignored in lab assignments because they exceeded the needs of the lab. This paper will address the adaptations that were made in the structure and pedagogy of the microcontroller course to implement the change in processors from the S12 to the ATmega32. It will document some of the troubles and surprises encountered along the way, and should provide some guidance for others contemplating such a change in their microcontroller labs.


How to Cite: Carroll, C. (2014) “First Experiences with the AVR ATmega32 Microcontroller”, 2014 ASEE North Midwest Section Conference. 2014(1). doi: https://doi.org/10.17077/aseenmw2014.1012