ECE 477 Design Review Team 12  Spring 2007

The Portable Composer tm Allows a musician to explore and record their musical ambitions while traveling or at home. Utilizing a 37-key keyboard, the user will be able to play and record music. An SD/MMC card slot will allow the user to save their composition in MIDI format for further editing via computer software.

Project-Specific Success Criteria An ability to save recordings to an SD card (in MIDI file format) An ability to translate the keys pressed on the keyboard into requested notes An ability to play polyphonic sounds based on the user's input An ability to display and adjust settings via an LCD with soft-keys An ability to load and play back a previous recording

Component Selection Rationale Major Components DSP Flash Memory DAC LCD Power Battery Charger

Component Selection Rationale DSP – Analog Devices SHARC 21262 Full 32-bit IEEE Floating Point Support Extensive C++ Library Support High Data Throughput Sufficient I/O Flash Memory – ST Micro. M25P80 Compatibility With DSP High Capacity Easy To Reprogram Through SPI

Component Selection Rationale DAC – Texas Instruments TLV320DAC23 Designed For Portable Devices Built-In Amplifier Low Power Standard Interface Protocols

Component Selection Rationale LCD – Matrix Orbital MOP-AL404 Wide Format Four Rows High Contrast Backlight

Component Selection Rationale Power Supply – MAX1774 Switch-Mode Regulator Designed For Portable Devices Automatic Switch To Battery Power Dual Voltage Outputs Over-Current And Over-Volt Detection Battery Charger – DS2715 Charge Up To 10 NiMH Cells Failure Detection

Packaging Design Commercially Manufactured Half-Size Keys Spacious Interior Met Overall Size Requirements for Portability

Power Subsystem

Dual Output DC-DC Converter

Second DC-DC Converter & Battery Charger

DAC & Headphone Amplifier

LCD Interface

Keyboard Interface

DSP

DSP Power Connections

Support Components

PCB Layout

Top View

Bottom View

Inner Layers

DAC / Headphone Circuit

MMC Card Socket

Flash / Debug Jumpers

Power Connectors

Battery Charge Circuit

Main Power Converter

1.2 Volt Power Circuit

DSP – All Layers

DSP – Top Layer

DSP – Bottom Layer

DSP – Bottom Layer

DSP – Inner Layers

Octave Key Pad

Software Design/Development Status

Project Completion Timeline

Questions / Discussion