The class:
ECE 118 is a class in which students are introduced to major topics related to computer interfacing such as parallel and serial interfacing, handshaking, D/A and A/D converters, busses, sensors, and actuators. Students are given weekly quizzes and a final on the material and are also expected to design, build, document, and demonstrate a project that implements the various interfacing topics presented in class.
The project:
It's only natural for a huge band geek to want to incorporate music whenever possible. My choice of projects was a no-brainer: I would make my computer play a Yamaha recorder.
Here is a schematic of the final circuit. The class is heavily hardware focused, so I attempted to complete the project with as little programming as possible--hence all the ICs.
Because of a limited budget, I used mostly components that I already had. The air compressor came from my car horn, which is capable of producing 138 decibels. This was clearly not the ideal compressor to use, but it was enough to get the project done without spending loads of money. As a result, the sound of the motor drowns out a lot of the recorder pitch as you can hear in the videos linked at the bottom of this page. You'll also notice that the speed of the motor changes with the pitch of the recorder to create the proper tone. This was done using pulse width modulation.
Read more about the project here.
The result:
Here are a few pictures of the final project:
Videos:
Theme from Back to the Future: .wmv .mov
