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🎨
Purdue Spark Challenge

DJ Pete Beat Sequencer

Embedded firmware for STM32 microcontrollers featuring advanced I2C, DMA, DAC, SPI integration with Adafruit NeoTrellis RGB keypads for interactive music production.

STM32CI2CDMADACSPIAdafruit NeoTrellisEmbedded Systems
STM32
ARM Cortex-M4
I2C/SPI
Communication Protocols
DMA
Direct Memory Access
RGB
NeoTrellis Keypads

Hardware Architecture

STM32 Embedded System Design

Advanced embedded firmware leveraging STM32 microcontroller capabilities with multiple communication protocols, real-time audio processing, and peripheral management for music hardware.

🎛️
STM32 MCU
ARM Cortex-M4
🌈
RGB Matrix
NeoTrellis Pads
🔊
Audio DAC
Real-time Output
DMA Engine
High-Speed Transfer
Communication: I2C + SPI + DMAReal-time Constraints: Sub-millisecond Response

Embedded Systems Features

🔗

Multi-Protocol Communication

Implemented I2C and SPI communication protocols for seamless integration with Adafruit NeoTrellis RGB keypads and external peripherals.

🎵

DMA-Driven Audio

Leveraged Direct Memory Access for real-time audio sample streaming to DAC, eliminating CPU bottlenecks in audio processing pipeline.

💡

Real-time RGB Control

Dynamic LED matrix management with per-key RGB control, creating visual feedback system synchronized with audio patterns.

⚙️

Low-Level Optimization

Hand-optimized ARM assembly routines for critical audio paths, achieving deterministic timing for professional music applications.

Interrupt-Driven Design

Sophisticated interrupt handling architecture ensuring responsive user input while maintaining audio timing precision.

🧠

Memory Management

Efficient memory allocation strategies for sample storage and real-time audio buffers in constrained embedded environment.

Implementation Deep Dive

Communication Stack

  • • I2C protocol for NeoTrellis keypad matrix
  • • SPI interface for high-speed audio data transfer
  • • Custom protocol layer for RGB synchronization
  • • Hardware abstraction layer for portability

Audio Processing Engine

  • • Real-time sample synthesis and playback
  • • DMA-based circular buffer management
  • • Hardware DAC integration for audio output
  • • Precision timing for beat synchronization

User Interface System

  • • 8x8 RGB LED matrix with individual control
  • • Capacitive touch sensing with debouncing
  • • Visual pattern feedback and status indicators
  • • Responsive UI with sub-10ms input latency

System Architecture

  • • Modular firmware design with clear separation
  • • Real-time OS concepts for task scheduling
  • • Efficient power management and sleep modes
  • • Robust error handling and recovery mechanisms

Project Achievements

Implemented complex embedded systems with multiple communication protocols

Created interactive RGB keypad interface for music production

Presented at Purdue Spark Challenge showcasing technical innovation

Demonstrated expertise in low-level hardware programming and real-time systems

Technical Specifications

STM32 Platform Integration

Developed comprehensive embedded firmware for STM32 ARM Cortex-M4 microcontroller, implementing multiple communication protocols and real-time audio processing capabilities for professional music production hardware.

168MHz
ARM Cortex-M4
512KB
Flash Memory
192KB
SRAM

Communication Protocols

Implemented sophisticated communication stack supporting I2C for keypad interface, SPI for high-speed data transfer, and DMA for efficient memory operations, ensuring reliable real-time performance.

I2C Master/SlaveSPI Full DuplexDMA Circular ModeGPIO Interrupt

Purdue Spark Challenge Recognition

Presented at Purdue's premier innovation showcase, demonstrating the intersection of embedded systems engineering and creative technology, highlighting both technical complexity and practical musical applications.

Innovation ShowcaseTechnical PresentationPrototype DemoPeer Recognition

Project Impact

Showcased embedded systems expertise through creative music technology, bridging hardware and artistic expression

Technical Innovation

  • • Advanced embedded systems architecture design
  • • Real-time audio processing on resource-constrained hardware
  • • Multi-protocol communication stack implementation
  • • Professional-grade timing precision for music applications

Educational Outcomes

  • • Demonstrated mastery of low-level embedded programming
  • • Applied real-time systems concepts in practical context
  • • Showcased creative application of engineering principles
  • • Enhanced understanding of hardware-software integration

Project Timeline

Academic Project - 2024
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