Synthesizer (Drum Machine Project)

This repository contains a ESP-32 based Syntheziser as a proof of concept board for the extension of the IES Elctronics Lab Drum Machine. The Project contains:

• Hardware design files (KiCad schematics, PCB, symbols, footprints, and 3D models)
• Firmware experiments for an ESP32-S2 using PlatformIO and Arduino framework
• Production export files (BOM, pick-and-place, netlist)
• LTspice simulation files for signal and quantization analysis

Project Structure

• Synthesizer.kicad_pro, Synthesizer.kicad_sch, Synthesizer.kicad_pcb: Main KiCad project
• Power.kicad_sch, Human_IO.kicad_sch: Additional schematic sheets/modules
• DrumMachine.pretty/, Sythezizer.pretty/: Custom footprint libraries
• 3D Modells/: 3D models used by KiCad
• Code/Synthesizer/: ESP32-S2 firmware workspace (PlatformIO)
• production/: Manufacturing exports (bom.csv, positions.csv, designators.csv, netlist.ipc)
• Simulations/: LTspice simulation setups and results

Hardware

Tooling

• KiCad 8 or newer recommended
• Optional: LTspice for simulation files in Simulations/

Open the PCB Project

1. Open KiCad.
2. Open Synthesizer.kicad_pro.
3. Verify custom footprint libraries are available:
   • DrumMachine.pretty/
   • Sythezizer.pretty/
4. If 3D models are missing, map paths to files in 3D Modells/.

Fabrication Outputs

Manufacturing data for production via JLC PCB is available in production/:

• bom.csv: Bill of materials
• positions.csv: Pick-and-place coordinates
• designators.csv: Reference designator mapping
• netlist.ipc: IPC netlist export

Firmware (ESP32-S2)

Firmware code is in Code/Synthesizer/ and uses PlatformIO. The Project is intended for 3rd Semester Students, therefore the Code is intended to be simple and easy to undesrtand without prior Coding experience.

Requirements

• VS Code + PlatformIO extension
• Or PlatformIO Core CLI (pio) installed
• USB data cable for ESP32-S2 board

Platform and Board Settings

From Code/Synthesizer/platformio.ini:

• Platform: espressif32
• Framework: arduino
• Board: esp32-s2-saola-1
• Monitor/upload speed: 460800
• USB CDC enabled on boot (ARDUINO_USB_CDC_ON_BOOT=1)

A custom board file also exists at Code/Synthesizer/boards/Synth.json.

Build and Upload

From Code/Synthesizer/ run:

pio run -e onetimeConversionTimeDelta
pio run -e onetimeConversionTimeDelta -t upload
pio device monitor -b 460800

If auto-port detection fails, set upload_port and monitor_port in platformio.ini.

Notes

• Most source files in src/ are standalone experiments/tests.
• test-DAClib pins the platform to a specific platform-espressif32 release URL in platformio.ini.
• One source name differs by case (cosineTest.cpp in folder vs CosineTest.cpp in config). If your OS/toolchain is case-sensitive, align these names.

Simulation

Simulations/ includes LTspice assets such as:

• QuantizationPWM.asc
• FFT/log/raw outputs for waveform and quantization studies

License

This project is licensed under the MIT License. See the LICENSE file for details.