1. Txt Msg DJ – Constr Anal 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 Text Message DJ aims to make song selection at a party a more democratic process. The Text Message 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 Text Message DJ will automatically parse messages, sort requests, and play the most popular. In addition to playing the song audio, the Text Message DJ will strobe lights in sync with the beat of the currently playing song.

2. Block Diagram

3. Micro Design Constraints
3 UART/USART (RasPi, GSM, DMX 512)
2 SPI - 250kBaud (SD Card, LCD)
>1 PWM (LED)
1 ATD (Audio Equalizer)
8 GPIO (Diagnostic LEDs)
JTAG Programming and Debugging

4. Microcontroller Comparison
ATxmega64A3U
PIC24EP512GP806
8/16bit
32 Mhz
64k Flash
4k SRAM
DMA Controller – Drastically reduces CPU load
Experience with architecture
Better documentation
Cheaper
Fits all design constraints
16-bit
70 Mhz
512k Flash
64k SRAM