SubGhzD (Sub-GHz Decoder) is a passive receiver app for decoding OOK/AM sub-GHz remote control signals from gate remotes, garage door openers, doorbells, home automation devices, and similar ISM-band transmitters. It identifies the protocol and displays decoded data in a scrolling list.

• Frequency: Default is 433.92 MHz. Adjustable via the encoder knob or on-screen numpad for other ISM bands (e.g., 315 MHz, 868 MHz).
• RF Amp (0 or 1): Enables/disables the internal RF amplifier. Use with care on strong signals.
• LNA gain (0–40): Low-noise amplifier gain. See Receive Quality Issues.
• VGA gain (0–62): Variable-gain amplifier gain. See Receive Quality Issues.
• Clear: Clears the decoded signal list from the screen. Does not affect the log file.
• Log: When checked, decoded packets are written to a timestamped CSV file on the SD card: LOGS/SUBGHZDLOG_YYYYMMDD_HHMMSS.CSV. The file header is ; Type; Bits; Data;.

Each decoded packet appears as a row with three columns: Type (protocol name), Bits (frame bit length), and Age (seconds since last received). The list deduplicates by signal content — repeated transmissions from the same remote update the age counter rather than adding new rows.

Selecting a row opens a detail view showing the protocol type, serial number, button code, counter value, and any additional decoded fields for that protocol.

For KeeLoq and Superrollo signals the detail view always shows the Fix code and the Encrypted hop value. The decrypted Hop value and the Save button are only shown when a matching manufacturer key is found in KEELOQKEYS/MFCODES. Without the key, the signal is received and displayed but cannot be decrypted and cannot be saved for retransmission.

When the Save button is available, it saves the decoded remote data to KEELOQREMOTES/<name>.KEELOQ on the SD card for use with the KeeLoq TX app.

45 protocols are currently implemented, covering fixed-code and some rolling-code (KeeLoq) systems across the 300–868 MHz ISM bands:

Princeton, Bett, CAME, CAME Atomo, CAME Twee, Chamberlain Code, Clemsa, Doitrand, Dooya, FAAC, Gate TX, Holtek, Holtek HT12X, Holtek HT6P20B, Honeywell, Honeywell WDB, Hörmann, IDO, Intertechno V3, KeeLoq, Kingates Stylo 4K, Linear, Linear Delta 3, Magellan, Marantec, Marantec24, Mastercode, Megacode, Nero Radio, Nero Sketch, Nice FLO, Nice FLO RS, Phoenix V2, Power Smart, Security+ V1, Security+ V2, SMC5326, Somify Keytis, Somify Telis, Star Line, X10, Legrand, Gangqi, Restaurant Pager, Superrollo (GW60/HCS361).

Note: Hörmann BiSecure (FM-based) is recognized but not implemented in this app as it requires FM demodulation.

Superrollo GW60 remotes use the HCS361 rolling-code chip with a 67-bit OOK frame at Te=450 µs. SubGhzD decodes these signals and displays them as protocol type Superrollo.

Full workflow:

1. Tune to 433.92 MHz and press the Superrollo remote button.
2. The signal appears in the list as Superrollo, 67 bits.
3. Open the detail view — Fix code and Encrypted hop are always shown.
4. If a Superrollo entry exists in KEELOQKEYS/MFCODES, the decrypted Hop value and the Save button also appear.
5. Press Save, enter a filename — the decoded remote is saved to KEELOQREMOTES/<name>.KEELOQ.
6. Open KeeLoq TX, load the file, and transmit.

Without a valid manufacturer key in MFCODES, steps 4–6 are not available. See KeeLoq TX for the MFCODES file format.

The Log checkbox state is saved to rx_subghzd.ini on the SD card when App Settings is enabled in the global Settings menu.