🎛️ BLE Macro Pad

ESP32 wireless macro pad with 12 buttons, a rotary encoder, and an OLED

12 configurable macro actions · Rotary volume control · OLED feedback · Bluetooth LE

A small DIY shortcut pad for media controls and everyday keyboard macros.

---

About

This is a BLE macro pad built around an ESP32, a 128 × 64 SSD1306 OLED, 12 pushbuttons, and a bare rotary encoder. The idea is simple: keep the shortcuts and media controls I use most on a small wireless device.

Every macro has its own function (b1() through b12()), so changing a shortcut is straightforward.

Important

Arduino IDE ESP32 board package: version 2.0.17. Use ESP32 by Espressif Systems v2.0.17 for this project. The current firmware does not compile with newer core versions.

The schematic shows the planned PCB connections. The firmware GPIO array still needs to be updated to match the board before flashing.

🖼️ Hardware Design

01 / Circuit Schematic

Electrical connections between the ESP32, buttons, OLED, and rotary encoder.

02 / PCB Layout

Board routing, component placement, and copper traces.

03 / PCB 3D View

Preview of the assembled board before fabrication.

🚀 Features

• Bluetooth LE keyboard: Send keyboard shortcuts and media-control commands wirelessly.
• Customizable macros: Dedicated b1()–b12() functions make actions easy to edit.
• Rotary encoder: Turn to adjust system volume up or down.
• OLED feedback: Show the last triggered action on a 128 × 64 monochrome display.
• Press-and-hold repeat: Configurable repeat interval for assigned button inputs (currently 300 ms).
• Expandable firmware: Reserve unused macros for application shortcuts, home automation, or future ESP-NOW integrations.

🧩 Components

Component	Purpose
ESP32 development board	Main controller + BLE
SSD1306 OLED, 128 × 64, I²C	On-device feedback
Bare EC11-style rotary encoder	Volume control
Momentary pushbuttons	Custom macros (up to 12 planned)
Custom PCB	Final electrical assembly

🎮 Button Layout

The schematic uses 12 independent pushbuttons. Each button connects between its GPIO and GND and is read with INPUT_PULLUP.

Button	GPIO (PCB schematic)	Default firmware action
SW1	GPIO 13	Up arrow
SW2	GPIO 25	Down arrow
SW3	GPIO 36 (VP)	Left arrow
SW4	GPIO 12	Right arrow
SW5	GPIO 39 (VN)	Space
SW6	GPIO 26	Next track
SW7	GPIO 34	Previous track
SW8	GPIO 14	Play / pause
SW9	GPIO 33	Custom
SW10	GPIO 35	Custom
SW11	GPIO 15	Custom
SW12	GPIO 18	Custom

Other connections: The OLED uses I²C; the rotary encoder is intended for volume control. Refer to the schematic for their PCB connections.

Note

These GPIOs are taken from the PCB schematic, not the prototype firmware's older buttons[] array. Update that array before flashing. GPIO 34–39 are input-only and don't have internal pull-ups on the ESP32, so buttons on GPIO 34, 35, 36 and 39 will need external pull-up resistors. Double-check the final netlist before ordering the board.

🛠️ Firmware Setup

1. In Arduino IDE Boards Manager, install ESP32 by Espressif Systems — 2.0.17. Do not upgrade the board package for this firmware; newer versions do not compile it.
2. Install these libraries:
   • BleKeyboard (ESP32 BLE Keyboard)
   • Adafruit GFX Library
   • Adafruit SSD1306
   • Wire (included with the ESP32 Arduino core)
3. Open the project sketch and select the correct ESP32 board and port.
4. Update the sketch GPIO assignments to match the schematic, and confirm the OLED I²C address (0x3C).
5. Upload the sketch, then pair the device named BLE Macro PAD with a BLE-capable host.

Caution

The hardware and firmware have not yet been tested together on the finished PCB. Check the schematic, power connections and encoder direction before regular use.

🧠 Customizing Macros

Each button has a small dedicated function. For example:

void b6() { bleKeyboard.write(KEY_MEDIA_NEXT_TRACK); printAction("NEXT TRACK"); }

To change a macro, edit the corresponding bN() function. printAction() sends a message to both the Serial Monitor and the OLED.

For the encoder, customize:

void encoderClockwise() {
  bleKeyboard.write(KEY_MEDIA_VOLUME_UP);
  printAction("VOLUME UP");
}

void encoderCounterClockwise() {
  bleKeyboard.write(KEY_MEDIA_VOLUME_DOWN);
  printAction("VOLUME DOWN");
}

Notes

This is a work in progress. Once the PCB is assembled, I’ll update the pin mapping and add photos and test results.

---

Built with ESP32 and Arduino C++.