PLAYLIST CREATION VIA BREATHALYZEREddie BertotMMI593 – DSP for Embedded Audio DevicesSpring, 2010

WHAT IS IT??? An alternative approach to musical playlist

creation via human-computer interaction (HCI). Specifically, a specialized protocol is discussed and implemented as the interface between an iPhone/iPod-Touch and an external gas-sensing circuit. A user first interacts with the system through a graphical UI and a basic breathalyzer. Values from the breathalyzer are analyzed and the device queues a playlist based on a predetermined set of predicates.In a nutshell: Depending on how inebriated you are, your iPod/iPhone plays different music

BASIC OPERATION:

USER INTERFACE First, hook

everything up and give the breathalyzer 9-12VDC

Press “Upload BAC Level” and blow through the unit – a value shows

Then generate a playlist!

MEDIA PLAYBACK The “Import Playlist”

button is pressed, and playback begins

Play/Pause and Skip

Current song is shown

INFO PAGE In case you don’t

know what to do…

ON THE INSIDE…

SIGNAL FLOW

THE PROTOCOL For transmission of data to iPhone, a binary

protocol was used. Its design was based primarily around the iPhone audio hardware: Slew Rate (frequency) limitations Capacitive nightmare

HOW DOES IT KNOW?!

It’s rough, but it works. Believe me. I’ve used it.

Demonstration