Imported from GitHub: nablum/pedalSHIELD-MEGA · commit 2df20f3 · license MIT

Description

Lo-fi programmable guitar pedal based on pedalSHIELD MEGA by Electrosmash.

README

A programmable guitar effects shield for Arduino MEGA, featuring OLED display, true-bypass footswitch, and DSP-ready input/output stages. Based on pedalSHIELD MEGA by ElectroSmash

📦 What’s Included

• ✅ KiCad project: schematic & PCB layout files for the hardware shield
• ✅ Arduino examples: boost, fuzz, delay, and other DSP sketches
• ✅ Bill of Materials: CSV file with component list and Mouser links
• ✅ Documentation: assembly guide, schematic diagrams, signal flow

🛠️ Assembly & Programming

1. Clone the repository:

   git clone https://github.com/nablum/pedalSHIELD-MEGA.git
   cd pedalSHIELD-MEGA
   

2. Build the PCB with KiCad or order the board from a fab using the provided Gerbers.

3. Solder the components according to the Assembly Guide.

4. Upload an effect sketch to your Arduino MEGA using Arduino IDE.

5. Plug and play:

   • Guitar IN → Input Jack
   • Output → Amp or Audio Interface
   • Power → USB or DC JACK.

🎛️ Example Effects

Each audio effect is implemented in a separate folder under firmware/effects/:

Effect Name	Description
BitCrusher	Reduces resolution and sample rate for lo-fi textures
Chorus	Modulates pitch with delay to create a thickening effect
ChorusOrVibrato	Blendable chorus and vibrato with adjustable depth
Clean	Transparent clean boost (reference circuit)
Distortion	Hard-clipping distortion effect
Echo	Simple digital delay with feedback loop
Fuzz	Saturated high-gain fuzz effect
MultiEffects	Combination of multiple effects in a single patch
OctaveCrusher	Bit reduction with added octave-up/down harmonics
Octaver	Mixes original with octave-down processed signal
Reverb	Simulates ambient reverb using delay-based algorithm
Tremolo	Volume modulation using a low-frequency oscillator
Vibrato	Pitch modulation effect for expressive shimmer

⚙️ Hardware Specs

• Compatible with Arduino MEGA 2560
• 128×64 I²C OLED display (SSD1306)
• True-bypass footswitch with relay
• Stereo audio jacks with analog preamp/output
• Powered via 12 V DC (center-negative)

❓ Troubleshooting

• OLED not lighting up → Double-check I²C wiring and 4.7k pull-up resistors.
• No audio output → Ensure signal chain is complete and shield is powered.
• Arduino upload fails → Check USB port, board selection, and serial permissions.

📚 Resources

• 🔬 pedalSHIELD-MEGA Documentation – ElectroSmash
  Official guide, schematics, theory of operation, and signal path details.

• 🧰 Assembly Guide – PDF
  Step-by-step instructions with images for building the pedalSHIELD‑MEGA hardware.

• 📦 u8glib – OLED Display Library
  Arduino graphics library used to drive the OLED screen (SSD1306, I²C).

• 💻 Arduino IDE Downloads
  Install the Arduino IDE to compile and upload code to the MEGA 2560.

🤝 Contributing

Contributions are welcome! You can:

• Submit new audio effects or improvements to existing sketches.
• Suggest hardware upgrades (e.g. better op-amps, analog filtering).
• Improve documentation or add new troubleshooting tips.

Please open a pull request against the main branch and follow the coding style of existing files.

📄 License

• Hardware (PCB files, schematics, BOM):
  Licensed under Creative Commons Attribution-NonCommercial 3.0 (CC BY-NC 3.0)

• Software (Arduino code, examples):
  Licensed under the MIT License

📬 Contact

Created by @nablum.
For questions or collaboration ideas, feel free to open an issue or reach out directly.