• SubGHz
  • Advanced
  • 10 min
  • Raw CDC

Recipe · Advanced · SubGHz

How to use the SubGHz Raw CDC adapter

The adapter wiki describes a SubGHz Raw CDC mode: a firmware-specific ASCII protocol over USB CDC to tune CC1101, start/stop raw reception, measure RSSI and transmit raw OOK timings.

CC1101 sub-GHz radio signal workflow.
This is the scriptable CC1101 path, not a clone of an existing desktop adapter protocol.

Wiring View

CC1101 BP adapter CSNCS GPIOSCKSCK GPIOMISOMISO GPIOMOSIMOSI GPIOGDO0data GPIOVCC3.3VGNDGND
Generated from the wiring summary: CC1101 to BP adapter.
Step 1

Workflow

  1. Configure the CC1101 pins and enter SubGHz Raw CDC adapter mode.
  2. Open the exposed USB CDC serial port from a terminal, Python script or custom tool.
  3. Start with receive/RSSI experiments before any transmit operation.
  4. Keep frequency, duty cycle and output power within local rules.

Serial protocol

Send ASCII commands over the adapter's USB CDC port, one per line ending with \n or \r\n.

CommandAction
V / ?Show adapter version / protocol help.
F433.920Tune to 433.920 MHz.
P433.920Apply the raw OOK/sniff preset at 433.920 MHz.
X21 / X00Enable / disable raw RX reporting.
XShow RX reporting state.
RMeasure peak RSSI.
G+350,-1050,+350,-350Transmit raw timings in microseconds.

Replace the example frequency as needed. Responses use OK for success, ERR:<reason> for errors, RAW:<timings> for received frames and RSSI:<value> for signal strength.

Timings are signed durations in microseconds: positive = mark/high, negative = space/low. TX requires an even number of timings, at least two. The payload also accepts a RAW: prefix, for example GRAW:+350,-1050,+350,-350.

Receive example

F433.920
X21

Incoming frames look like this; send X00 to stop reporting:

RAW:+350,-1050,+350,-350,+350,-1050
RSSI:-54

Result

What success looks like

Your host script can tune the radio, observe RSSI or receive raw OOK timing frames through the serial port.

Troubleshooting

  • Wrong CC1101 SPI or GDO0 pin selected during adapter setup.
  • CC1101 powered at 5V instead of 3.3V.
  • Wrong frequency band for the module or region.
  • Trying to decode Wi-Fi/BLE with CC1101; use the correct radio for the target band.

Next steps

  • Use normal SubGHz mode scan and receive first to validate the module.
  • Build a Python logger around the Raw CDC serial port.
  • Use LittleFS .sub workflows when replaying supported files from the firmware UI.

SubGHz Raw CDC adapter FAQ

What is the SubGHz Raw CDC adapter for?

It exposes the CC1101 over USB CDC with a small ASCII protocol for tuning frequency, enabling raw RX, reading RSSI and transmitting raw OOK timing sequences.

Why does this adapter not work with a standard desktop radio tool?

It is firmware-specific rather than an emulation of a common desktop protocol. Use a serial terminal, pyserial script or custom host tool that speaks its ASCII commands.

Which signals are suitable for Raw CDC experiments?

Use simple authorized OOK or raw Sub-GHz lab signals where timing matters more than high-level decoding. It is not intended for Wi-Fi, BLE or unrelated 2.4 GHz protocols.

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