Txt Msg DJ – Software DesignTxt Msg DJ – Software Design

By: Kyle Brown

Abstract: Everyone wants to dance to their favorite songs at a party, but

rarely do guests have much say in song selections and playlists. The Txt Msg DJ aims to make song selection at a party a more democratic process. The Txt Msg DJ is a standalone unit that creates and maintains a party playlist based on song requests sent from party guests via SMS. Guests can send text messages containing song names and the Txt Msg DJ will automatically parse messages, sort requests, and play the most popular. In addition to playing the song audio, the Txt Msg DJ will strobe lights in sync with the beat of the currently playing song. In order to maintain control of the party, users will be able to insert an SD card with predefined whitelisted and blacklisted songs.

Raspberry Pi Software Considerations

Raspberry Pi Software Considerations

UART RasPi Communication – Send/receive asynchronous commands and song requests

Track Identification – Quickly and accurately determine what the user “meant” to request

Track Playback – Retrieve songs from an online service, maintain a queue

Station Generation – Retrieve songs similar to recently played songs

Raspberry Pi Software SolutionsRaspberry Pi Software Solutions

UART RasPi Communication – Python and modified miniterm

Track Identification – Last.fm API track.search

Track Playback – MPlayer and Grooveshark, via gsclient plugin

Station Generation – Last.fm API track.getSimilar

Microcontroller Software Considerations

Microcontroller Software Considerations

GSM Module – Send/receive asynchronous SMS messages

DMX512/LED – Control lights in real-time with music

SD Card – Read config files once, on bootup

LCD Screen – Display current track information, as well as queue information

Microcontroller SolutionsMicrocontroller Solutions

GSM Module – Interrupt driven (UART from GSM module)

DMX512/LED – Interrupt driven using timer

SD Card – Run on initialization LCD Screen – Interrupt driven (UART from

Raspberry Pi)

SMS FlowSMS Flow

Light FlowLight Flow

SD Card FlowSD Card Flow

LCD Screen FlowLCD Screen Flow