In 2009 I developed my first automated cultivation chamber for growing gourmet mushrooms. It consisted of a controller that modulated a humidifier to alter the humidity level, a heater to alter the temperature, and an exhaust fan to evacuate excess carbon dioxide. At the time, I was producing some of my first practical uses of the C programming language, nearly a decade after learning the basics. This was also my first of many automation projects using the ATMega168 microcontroler, and on my first Arduino board, the Duemilanove. Although I still use ATMega MCUs today, at the time, the scope of what I wanted to do required more connectivity and processing power. Therefore, I utilized a serial connection to a computer running linux, which hosted a control interface on a web server. However, in 2012 the Raspberry Pi was released. It was the first of its kind, offering a 700 Mhz processor that could run a full distribution of Linux, 17 general purpose input/outputs (GPIOs), SD card storage, HDMI/VGA output, and USB connectivity, all for under $30. With it now being attainable to reduce the size of my control system down to the equivalent of a deck of playing cards, I tasked myself with redesigning the code to work on this new hardware.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!