The popular AT89S8252 Flash Microcontroller Board published in the December 2001 issue of Elektor Electronics was developed for the ‘Microcontroller Basics’ course. Since then many thousands of the boards have been built. First, the bad news: Atmel have made the AT89S8252 obsolete! But now the good news: not only is the pin-compatible AT89S8253 a drop-in replacement, but it even offers enhancements over its predecessor.