IR Transfer (Flipper Zero)

October 16, 2025 · View on GitHub

File transfer over infrared between two Flipper Zero devices using the NEC protocol for both control and data.

[WARNING] This repo is public for testing purpose only atm, It is not working properly as intented

✨ Features

  • Send / Receive any file from the SD card.
  • Robust, simple flow:
    • Filename sent first (null-terminated, no length field).
    • File size sent as 4 bytes big-endian.
    • File data sent byte-by-byte via NEC frames.
    • Final XOR checksum (over all data bytes) confirms success.
  • UI:
    • Landing: choose Send or Receive.
    • Send: file picker, status + progress bar, Send/Cancel.
    • Receive: target path, status + progress bar, Reset when idle, Cancel during activity.
  • Output folder: /ext/downloads (created automatically).
  • Name collision handling (suffix appended if needed).

📦 Requirements

  • Flipper Zero firmware repo (Momentum or official) with FBT toolchain.
  • This project lives under your firmware’s applications_user/ directory.

🚀 Install

cd <firmware-root>                    # e.g. ~/flipper/Momentum-Firmware
mkdir -p applications_user
cd applications_user
git clone https://github.com/WBP20/ir_transfer.git

🛠️ Build & Run

From the firmware root:

./fbt launch APPSRC=applications_user/ir_transfer

If you changed code and the build seems stale:

./fbt distclean
./fbt launch APPSRC=applications_user/ir_transfer

You might see an unrelated warning (e.g. an external app with a bad appid); it does not affect IR Transfer.

🧭 Usage

Sender

  1. Open the app → Send.
  2. Pick a file under /ext/....
  3. Press Send to start (press OK again to Cancel).
  4. On completion: status shows File sent.

Receiver

  1. Open the app → Receive (status: awaiting signal).
  2. During transfer: progress bar and Cancel (center button).
  3. After success: the file is saved to /ext/downloads/<filename> (suffix added if the name already exists).

📡 Protocol (NEC)

  • Filename: sent as bytes terminated by '\0' (no length).

  • Size: 4 bytes big-endian total size.

  • Data: 1 byte per NEC frame (simple and reliable).

  • Checksum: single-byte XOR of all data bytes, sent at the end.

  • Receiver workflow:

    • Write incoming bytes to temporary file /ext/tmpfile.

    • On checksum match:

      • Move to /ext/downloads/<original_name> (add suffix if needed).

    • On checksum mismatch:

      • Remove the temporary file and show error.

📂 Project Structure

ir_transfer/
├─ application.fam
├─ ir_main.c
├─ ir_main.h
├─ views/
│  ├─ landing_view.c/.h
│  ├─ sending_view.c/.h
│  └─ receiving_view.c/.h
├─ infrared/
│  ├─ infrared_transfer.c
│  └─ infrared_transfer.h
└─ utils/
   └─ draw_utils.h

🧰 Troubleshooting

  • Missing imports / unresolved symbols Ensure all .c files are matched by the sources globs in application.fam. Folder names are lowercase: views/, infrared/, utils/.

  • Include path / case sensitivity Use ../infrared/... and ../utils/... (not ../Infrared/ or ../Utils/).

  • Build noise from other apps External app warnings in your firmware tree don’t affect this app.

🗺️ Roadmap

  • Optional batching/optimizations while staying NEC.
  • (Future branch) Higher throughput mode (RAW/Manchester) with CRC/ACK.

📝 License

MIT 2.0