
OSO BOOK C1
joeycastillo/The-Open-Book
For details on how to build, test and use Open Book, I've made documentation available here.

Lo-fi programmable guitar pedal based on pedalSHIELD MEGA by Electrosmash.
PedalSHIELD MEGA is an open-source printed circuit board by nablum, from the nablum/pedalSHIELD-MEGA repository on GitHub, published under the MIT licence. It is a 2-layer board of 62 × 122 mm with 38 parts on 66 nets, routed with 234 tracks and 48 vias.
Its parts include 15 resistors, 11 capacitors, 4 switches, 2 connectors and 1 IC. It belongs with the audio and music boards of this library.
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
Clone the repository:
git clone https://github.com/nablum/pedalSHIELD-MEGA.git
cd pedalSHIELD-MEGABuild the PCB with KiCad or order the board from a fab using the provided Gerbers.
Solder the components according to the Assembly Guide.
Upload an effect sketch to your Arduino MEGA using Arduino IDE.
Plug and play:
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 |
🔬 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.
Contributions are welcome! You can:
Please open a pull request against the main branch and follow the coding style of existing files.
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
Created by @nablum.
For questions or collaboration ideas, feel free to open an issue or reach out directly.
| Qty | Value | Footprint | References |
|---|---|---|---|
| 9 | 4.7k | pedalSHIELD_MEGA:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R3, R4, R6, R9, R10, R12, R13, R14, R15 |
| 5 | 6.8n | pedalSHIELD_MEGA:C_Rect_L7.0mm_W2.5mm_P5.00mm | C2, C5, C7, C8, C9 |
| 3 | 100k | pedalSHIELD_MEGA:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R5, R7, R8 |
| 3 | 4.7u | pedalSHIELD_MEGA:CP_Radial_D4.0mm_P1.50mm | C3, C6, C10 |
| 2 | 100n | pedalSHIELD_MEGA:C_Rect_L7.0mm_W2.5mm_P5.00mm | C1, C11 |
| 2 | 1M | pedalSHIELD_MEGA:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1, R2 |
| 2 | ~ | pedalSHIELD_MEGA:Jack_6.35mm_Neutrik_NMJ6HCD2_Horizontal | J1, J2 |
| 2 | ~ | pedalSHIELD_MEGA:SW_PUSH_104-0013-EVX | SW3, SW4 |
| 1 | 1M2 | pedalSHIELD_MEGA:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R11 |
| 1 | 270p | pedalSHIELD_MEGA:C_Rect_L7.0mm_W2.5mm_P5.00mm | C4 |
| 1 | 500k | pedalSHIELD_MEGA:Potentiometer_Piher_PT-10-H01_Horizontal | RV1 |
| 1 | ~ | pedalSHIELD_MEGA:DIP-8_W7.62mm_Socket_LongPads | U1 |
| 1 | ~ | pedalSHIELD_MEGA:SF17020F030221RL015 | SW1 |
| 1 | ~ | pedalSHIELD_MEGA:LED_D3.0mm | D1 |
| 1 | ~ | pedalSHIELD_MEGA:SW_SPDT_ 100SP1T1B1M1QEH | SW2 |
| 1 | ~ | pedalSHIELD_MEGA:LCD_OLED_SH1106 | LCD1 |
| 1 | ~ | pedalSHIELD_MEGA:Arduino_Mega2560_R3_Shield_pedalSHIELD_MEGA | A1 |
The 37 most common of 38 parts.
It measures 62 × 122 mm and has 2 copper layers, 1.6 mm thick.
38 parts. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
From the nablum/pedalSHIELD-MEGA repository on GitHub, at the commit this page was made from: the board is hardware/kicad/pedalSHIELD_MEGA.kicad_pcb and its schematic hardware/kicad/pedalSHIELD_MEGA.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).

joeycastillo/The-Open-Book
For details on how to build, test and use Open Book, I've made documentation available here.


hackclub/OnBoard
💡 Join 1,000 teenagers and make your first PCB with a $100 grant!


Ardumower/ardumower
Develop an open source robotic lawn mower (HW+SW reference platform)

CRImier/MyKiCad
My KiCad boards. Can't be bothered uploading individually anymore, so here you go.

