haf700-lcd

Drive the Cooler Master HAF 700 EVO case LCD from Linux — no Windows, no MasterPlus.

The HAF 700 EVO's front LCD is the panel the vendor's MasterPlus app controls on Windows only. This tool gives you full control from Linux: show any image, GIF, or video on it, and screenshot what's currently displayed.

How it works (the TL;DR of the reverse-engineering)

The HAF 700 EVO LCD isn't a dumb display — it's a tiny rooted Android device (Android 4.4.2 on an RDA8810 ARM SoC, 480×480 screen) that hangs off your motherboard's USB as Cooler Master USB ID 2516:01c1. Its second USB interface is a standard ADB (Android Debug Bridge) interface.

All MasterPlus does is:

1. transcode your image/GIF/video into a 480×480 H.264 MP4,
2. adb push it into the on-panel display app (com.magic.box), and
3. update one Android shared-preference so the app plays your file.

haf700-lcd does exactly that, from Linux, with adb + ffmpeg. No custom USB protocol, no driver, no reverse-engineered firmware — it's just an Android device you talk to with adb.

As far as I can tell this is the first public tool to drive this panel from Linux. If you find an earlier one, please open an issue — I'd love to link it.

Requirements

• Linux (tested on Ubuntu)
• adb — sudo apt install android-tools-adb (or your distro's android-tools)
• ffmpeg + ffprobe — sudo apt install ffmpeg
• The HAF 700 EVO front-panel USB cable plugged into a motherboard USB header (it usually is)

The panel ships rooted (it has su), which is what lets the app's protected files be written.

Install

git clone https://github.com/Kyzcreig/haf700-lcd
cd haf700-lcd
chmod +x haf700_lcd.py
# optional: symlink onto your PATH
sudo ln -s "$PWD/haf700_lcd.py" /usr/local/bin/haf700-lcd

No Python dependencies beyond the standard library (it shells out to adb/ffmpeg).

Usage

# verify the panel is detected
haf700-lcd info

# show an image / gif / video (auto-cropped to fill the square, NO black bars)
haf700-lcd show my-art.png
haf700-lcd show loop.gif
haf700-lcd show clip.mp4

# letterbox instead of crop (keeps the whole frame, adds bars)
haf700-lcd show wide.jpg --fit contain

# loop a still / short gif for N seconds (default 6)
haf700-lcd show logo.png --seconds 10

# capture what's currently on the panel (it's an Android framebuffer!)
haf700-lcd screenshot proof.png

# undo the last `show`
haf700-lcd restore

info output

HAF700 LCD detected:
  adb serial : 1234567890ABCDEF
  android    : 4.4.2  (device codename: etau)
  Physical size: 480x480
  currently showing: 1799990001.mp4

How show works internally

1. ffmpeg transcodes the source to a 480×480 H.264 baseline MP4 at 25 fps. The default --fit cover scales-to-fill and center-crops so there are no black bars; --fit contain letterboxes instead. Stills and short GIFs are looped to fill the requested duration.
2. adb push lands the MP4 on the panel, then (as root via the panel's su) it's copied into /data/data/com.magic.box/files/ with the right owner/mode.
3. The currentType key in com.magic.box's shared_prefs/magic.xml is rewritten to point at the new file (the existing 29-byte config header is preserved; only the trailing length-prefixed filename changes).
4. The display app is restarted (am force-stop + am start) so it re-reads the pref and loops your content.

Protocol notes (for the curious / for porting)

See PROTOCOL.md for the full reverse-engineering writeup: USB descriptors, the ADB interface signature, the com.magic.box file/pref mechanism, the currentType byte layout, and the com.rdamicro.pcdatareceiver package that handles the hardware-monitor display modes.

Caveats / not-yet-done

• Image / GIF / video display: working. ✅
• Clock & hardware-monitor display modes (CPU temp etc.) use a different currentType header and the com.rdamicro.pcdatareceiver package — not yet mapped. PRs welcome.
• Only tested on one HAF 700 EVO (2024). Other Cooler Master cases/coolers that use the same MagicBox Android panel may work as-is — reports welcome.

Development

The hardware-coupled commands need a real panel, but the tricky logic — the currentType (magic.xml) codec and the ffmpeg "no black bars" filter — is pure and unit-tested. CI runs them plus a CLI launch smoke test on every push:

python -m pytest -v        # 12 tests, no hardware needed

License

MIT — see LICENSE.

Disclaimer

Not affiliated with or endorsed by Cooler Master. "HAF", "MasterPlus", and "Cooler Master" are trademarks of their respective owner. Use at your own risk; this writes to the panel's Android storage via its own (vendor-shipped) root shell.