USB2BLE MIDI Bridge

This project converts USB MIDI signals from Yamaha Digital Piano to Bluetooth MIDI (BLE MIDI), enabling wireless MIDI connectivity.

Tested on Yamaha YDP-144.

Hardware Requirements

• ESP32-S3 DevKitC board
• USB Type A breakout board
• Yamaha Digital Piano (with USB MIDI support)

Wiring Instructions

Connect the USB Type A breakout board to ESP32-S3 as follows:

• USB D+ → GPIO20
• USB D- → GPIO19
• USB VCC → 5V
• USB GND → GND

Usage

1. Connect the hardware according to the wiring instructions
2. Flash the program to ESP32-S3
3. Connect a USB cable between the piano and the USB breakout board
   • Piano side: Standard USB-B port
   • Breakout board side: USB-A port
4. Turn on Bluetooth on your mobile device/tablet and search for the MIDI device
5. Start using - the piano's MIDI signals will now be transmitted via Bluetooth to the connected device

Build and Flash

idf.py -p /dev/your_usb_to_serial_port flash

Flash Prebuilt Release Firmware

Download firmware files from the latest GitHub Release.

Recommended: single merged binary

Download:

• usb2ble_midi_bridge_merged.bin

Install esptool if needed:

python -m pip install esptool

Flash it at offset 0x0:

python -m esptool --chip esp32s3 -p /dev/your_usb_to_serial_port -b 460800 \
  --before default_reset --after hard_reset \
  write_flash --flash_mode dio --flash_size 8MB --flash_freq 80m \
  0x0 usb2ble_midi_bridge_merged.bin

On macOS the serial port is usually like /dev/cu.usbserial-120 or /dev/cu.usbmodem*.

Advanced: separate binaries

Download:

• bootloader.bin
• partition-table.bin
• usb2ble_midi_bridge.bin

Flash them with explicit offsets:

python -m esptool --chip esp32s3 -p /dev/your_usb_to_serial_port -b 460800 \
  --before default_reset --after hard_reset \
  write_flash --flash_mode dio --flash_size 8MB --flash_freq 80m \
  0x0 bootloader.bin \
  0x8000 partition-table.bin \
  0x10000 usb2ble_midi_bridge.bin