🎛️ MacroPad DIY V1

A custom 9-key macropad with rotary encoder and OLED display, powered by Arduino Pro Micro.

✨ Features

• 9 mechanical keys with customizable macros (shortcuts, git commands, key combinations)
• EC11 rotary encoder for volume control with mute/unmute toggle
• 1.3" OLED display with fixed header (name + clock), animated volume bar, and visual feedback for each key press
• Clock sync from PC via USB Serial
• Volume sync from PC for an always-accurate volume bar
• Anti-flood and noise protection to prevent Arduino lockups

🔧 Hardware Components

Component	Specification	Notes
Arduino Pro Micro	ATmega32U4 5V/16MHz	Native HID support (keyboard/mouse over USB)
OLED Display	1.3" SH1106 I2C	I2C address: 0x3C (verify with I2C scanner)
Rotary Encoder	EC11E12 (5 pins)	4 pulses per detent, with built-in push button
Mechanical Switches	Cherry MX (x9)	Any variant (Red, Blue, Brown, etc.)
Keycaps	Cherry MX compatible (x9)	Any profile (OEM, DSA, SA, etc.)
Perfboard / PCB	Optional	Recommended for encoder soldering
DuPont Wires	Male-to-Male	For breadboard/PCB connections

🔌 Wiring Diagram

Arduino Pro Micro Pin Table

Component	Component Pin	Arduino Pin	Notes
Encoder CLK	A (left, 3-pin side)	0 (TX)	Hardware interrupt ✓
Encoder DT	B (right, 3-pin side)	1 (RX)	Hardware interrupt ✓
Encoder GND	C (center, 3-pin side)	GND
Encoder SW	Either pin (2-pin side)	14	Mute button
Encoder SW GND	Other pin (2-pin side)	GND	Interchangeable
Display SDA	SDA	2 (SDA)	I2C - dedicated pin
Display SCL	SCL	3 (SCL)	I2C - dedicated pin
Display VCC	VCC	VCC	5V or 3.3V depending on display
Display GND	GND	GND
Key 1	One pin	4	Other pin to GND
Key 2	One pin	5	Other pin to GND
Key 3	One pin	6	Other pin to GND
Key 4	One pin	7	Other pin to GND
Key 5	One pin	8	Other pin to GND
Key 6	One pin	9	Other pin to GND
Key 7	One pin	15	Other pin to GND
Key 8	One pin	A0	Other pin to GND
Key 9	One pin	A1	Other pin to GND

⚠️ IMPORTANT: Pins 2 and 3 are reserved exclusively for the I2C display. Do NOT connect any other components to these pins.

Wiring Notes

• All Cherry MX switches have 2 pins: one goes to the designated Arduino pin, the other to GND
• Multiple components can share the same GND pin on the Arduino
• The EC11 encoder has 3 pins on one side (rotation) and 2 pins on the other (button). The center pin on the 3-pin side is always GND
• If the volume direction is reversed, swap pins 0 and 1 in the code: Encoder myEnc(1, 0);

⌨️ Macro Map

Key	Action	Shortcut	Use
1	Screenshot	Win+Shift+S	Partial screen capture
2	Task Manager	Ctrl+Shift+Esc	Opens Task Manager
3	Open CMD	Win+R → cmd → Enter	Opens Command Prompt
4	Git Status	git status + Enter	Repository status
5	Git Pull	git pull + Enter	Pull latest changes
6	Git Commit & Push	git add . && git commit -m "" && git push	Places cursor between quotes for commit message
7	Format Document	Shift+Alt+F	Auto-format (VS Code)
8	Search in Files	Ctrl+Shift+F	Global search (VS Code)
9	Toggle Comment	Ctrl+/	Comment/uncomment line (VS Code)
Encoder	Volume	Rotation	Volume up/down
Encoder Press	Mute	Press	Toggle mute/unmute

📦 Installation

1. Arduino IDE Setup

1. Open Arduino IDE
2. Go to Tools → Board
3. Select Arduino Leonardo

   ⚠️ The Arduino IDE does not natively recognize the Pro Micro. If "Arduino Pro Micro" is not listed in the board menu, select Arduino Leonardo instead — it is 100% compatible since both boards use the same ATmega32U4 chip.

4. Select the correct COM port under Tools → Port

2. Arduino Libraries

Install the following libraries via Tools → Manage Libraries:

• Adafruit GFX Library
• Adafruit SH110X
• HID-Project
• Encoder

3. Upload the Sketch

1. Open macropadDIY.ino in the IDE
2. Click Upload

Upload troubleshooting: The Pro Micro may require a double reset to enter bootloader mode. If the upload fails with "Access denied" or similar errors:

1. Click Upload in the IDE
2. When the console shows "Sketch uses XXX bytes..."
3. Quickly connect RST to GND twice (touch, release, touch, release in under 1 second)
4. The IDE detects the bootloader and completes the upload

4. PC Sync Script (Python)

The Python script sends the current time and real system volume to the macropad.

Requirements:

pip install pyserial pycaw comtypes

Manual launch:

pythonw "path/to/sync_time.py"

Included .bat files:

File	Function
start_sync.bat	Starts the script in background (no window)
stop_sync.bat	Stops the script
macropad_sync.bat	For automatic startup with Windows

Auto-start on boot:

1. Press Win + R
2. Type shell:startup and press Enter
3. Copy macropad_sync.bat into the folder that opens

🖨️ 3D Printed Case

The case is designed to house all components. STL files for 3D printing are located in the /3d-models/ folder.

Recommended settings: PLA or PETG, 0.2mm layer height, 20% infill.

💡 Assembly tip: You may need to slightly file down the corners of the key grid to fit it into the bottom case. Sand gradually and test fit frequently.

📁 Project Structure

macropadDIY/
├── codebase/             
│   ├── macropadDIY
│      └── macropadDIY.ino # Main Arduino sketch
├── sync_time.py           # Python script for time & volume sync
├── start_sync.bat         # Start sync in background
├── stop_sync.bat          # Stop sync
├── macropad_sync.bat      # For Windows auto-startup
├── wiring-schema.fzz      # Wiring schema
├── 3D projects/             # STL files for the case
│   ├── case-top.stl
│   └── case-bottom.stl
└── README.md              # This documentation

🐛 Troubleshooting

Display not turning on:

• Check SDA (pin 2) and SCL (pin 3) connections
• Try the alternate I2C address 0x3D in the code
• Reset the Arduino after connecting the display

Volume goes crazy or only moves in one direction:

• Check encoder solder joints (especially the 3 rotation pins)
• Add 100nF ceramic capacitors between pin A/GND and pin B/GND
• Verify the encoder pins are on 0 (TX) and 1 (RX)

"Access denied" error during upload:

• Close the Serial Monitor and any program using the COM port
• Stop sync_time.py with stop_sync.bat
• Perform a double reset (RST → GND twice)

Clock shows --:--:

• The sync_time.py script is not running
• Start it with start_sync.bat
• Make sure no other program is using the COM port

Keys type wrong characters:

• Check the Windows keyboard layout (the sketch is optimized for US International)
• Special characters (&, ", /) may vary depending on the layout

📷 Gallery

🎥 Demo

video-demo.mp4

📄 License

MIT License