Bruce Firmware on M5Stack: How to Flash It and Fix "CC1101 / nRF24 Not Found" (2026)

PINGEQUA Lab · Bruce firmware · 7 min read · Updated 2026-06-25

A brand-new RF cap that reports "not found" feels like dead hardware — but on M5Stack boards it almost never is. Here's the real cause, with the exact Bruce settings and pin values that fix it.

Quick answer If your M5Stack RF module shows "CC1101 not found" or "nRF24 not detected" in Bruce, the radio is almost never dead. The two most common causes: (1) you haven't flashed Bruce firmware yet — or you're on an old build with a known SPI/power bug — and (2) the BrucePins.conf pin map doesn't match your board. The fix: flash the current Bruce release (1.15, May 2026) at bruce.computer/flasher, set the correct pins, then in the app go to RF → Config → RF Module and pick CC1101 (on SPI / Legacy), and restart.

What is Bruce, and which devices does it support?

Bruce is an open-source offensive-security firmware for ESP32 devices, maintained by pr3y at BruceDevices/firmware. It runs on the M5Stack Cardputer, StickC Plus 1.1 / Plus 2, StickS3, M5Core / Core2, plus Lilygo T-Deck / T-Embed boards. It's the firmware that turns these handhelds into Sub-GHz (CC1101) and 2.4 GHz (nRF24L01+) RF tools — which is why a PINGEQUA RF cap needs Bruce flashed before the radios appear.

Step 1 — Flash Bruce (three ways, easiest first)

You do not need a desktop toolchain or COM-port wrangling.

Method How Best for
Web flasher Open bruce.computer/flasher in Chrome or Edge, plug in via USB, pick your board, click flash Everyone — no install
M5Launcher OTA Install M5Launcher, update Bruce over the air Quick updates on a flashed device
m5burner Flash from the M5Stack m5burner desktop app If you already use M5Burner

Pick the build that matches your exact board (e.g. m5stack-cardputer, m5stack-cplus2, m5stack-sticks3). Using the wrong board target is itself a cause of "not found." PINGEQUA also hosts an in-browser flasher at flash.pingequa.com for its boards.

Step 2 — Why "not found" happens (the real causes, in order)

Based on Bruce's own wiki and recurring GitHub issues, the error comes down to:

  1. Bruce not flashed, or an old/buggy build — by far #1. Some early builds (e.g. 1.12 / 1.13) shipped SPI-timing and power-management regressions that caused false "not found" on good hardware; updating fixes them.
  2. BrucePins.conf pin map wrong for your board — the radios are wired to chip-select/IRQ pins that must be declared correctly.
  3. Module not selected in the menu — Bruce defaults may not point at your external CC1101/nRF24 until you pick it.
  4. Wrong-model cap or poor seating — an ADV cap on a v1.1 (or a loose seat) never enumerates. See Cardputer ADV vs v1.1 compatibility.
  5. Config not applied to the right storage — on some devices BrucePins.conf must be edited in both the SD card and LittleFS, then the device restarted.
  6. A genuinely faulty module — rare, and the last thing to suspect.

Step 3 — The fix checklist

1. Flash / update Bruce to the latest build

Use bruce.computer/flasher and the correct board target. This alone clears the old-build SPI/power bugs.

2. Set the pin map (BrucePins.conf)

Bruce reads its radio pin assignments from BrucePins.conf. The radios won't enumerate until the chip-select (CS) and IO0 pins match your board's wiring.

Cardputer ADV pin values (for the PINGEQUA Cardputer ADV CC1101 + nRF24 caps):

Section CS pin IO0 pin
CC1101_Pins 13 5
NRF24_Pins 6 4

Two things people miss: edit BOTH copies — BrucePins.conf exists on the SD-card root and in the device LittleFS; Bruce reads one or the other depending on build, so set the same values in both and restart. And the easiest editor is the WebUI: on the device go to Files → WebUI, join your Wi-Fi, open the IP shown on screen in a browser (default login admin / bruce), edit brucepins.conf there, and force a restart.

The RF Pack S3 for StickS3 ships a quick-start card with the exact Bruce menu path and pin reference, so you skip this step.

3. Select the module in Bruce

Go to RF → Config → RF Module and choose CC1101 (on SPI). On boards/builds that need it, pick the (Legacy) driver — CC1101 (Legacy) and nRF24 (Legacy) — which uses the older, broadly-compatible SPI path.

Quirk worth knowing — "CC1101 only works after I open nRF24 first." On dual-radio boards that share one SPI bus, the CC1101 can fail to come up if you boot straight into it, because its init code assumes the SPI bus is already configured — opening the nRF24 first configures the bus, and then the CC1101 works (Bruce issue #1909). The hardware fix is buffered/isolated SPI so order doesn't matter — what the RF Pack S3's SN74 buffer does.

4. Re-seat and confirm the band

Power off, re-seat the cap firmly on the correct header, power on, and re-open the RF menu. Confirm your antenna and band match the module (a 433 MHz board is tuned for 433, not 868/915).

5. Still "not found"?

Now it's worth support. Include your device model, Bruce version, board target, and BrucePins.conf so the cause (almost always config) can be spotted fast.

Device-specific notes

  • Cardputer ADV (Hydra RF caps): flash latest Bruce, update brucepins.conf via WebUI, then force restart. The ADV uses its rear 2×7 header for SPI.
  • Cardputer v1.1 (3-in-1 module): plug-and-play on the v1.1 headers; flash Bruce, select CC1101/nRF24 in the RF menu.
  • StickS3 (RF Pack S3): use the m5stack-sticks3 Bruce build (native pin map) and the (Legacy) drivers. StickS3 support was stabilized in late-2025 → early-2026 Bruce builds (issue #2148) — so a current build matters here especially.
  • StickC Plus / Plus 2 (Stick RF 424): use the matching m5stack-cplus / cplus2 build.

FAQ

Why does Bruce say "CC1101 not found" / "nRF24 not detected"?
Most often the firmware isn't flashed (or is an old build with a known SPI/power bug), or the BrucePins.conf pin map doesn't match your board. Flash the current Bruce, fix the pins, select the module under RF → Config → RF Module, and restart. The module is rarely actually dead.
How do I flash Bruce without a desktop toolchain?
Use the official web flasher at bruce.computer/flasher in Chrome or Edge — plug in over USB, choose your board, click flash. No esptool, no COM-port setup.
What's the current Bruce version?
1.15, released 2026-05-25. Keep it current — several "not found" reports trace to outdated builds.
Should I pick "CC1101" or "CC1101 (Legacy)" in the menu?
Try CC1101 (on SPI) first; if the radio still isn't detected, switch to CC1101 (Legacy) (and nRF24 (Legacy)), which uses the older, more broadly compatible SPI driver path.
Do I edit BrucePins.conf on the SD card or internal storage?
Both can apply. If editing only one doesn't take effect, edit BrucePins.conf in both the SD card and LittleFS, then restart. The simplest editor is the on-device WebUI (Files → WebUI, open the IP in a browser, login admin / bruce).
What pin values does the Cardputer ADV use?
For the PINGEQUA Cardputer ADV CC1101 + nRF24 caps: CC1101_Pins → CS 13, IO0 5; NRF24_Pins → CS 6, IO0 4. Set these in BrucePins.conf (both copies) and restart.
Why does my CC1101 only work after I open the nRF24 first?
On dual-radio boards sharing one SPI bus, the CC1101's init assumes the bus is already configured; opening the nRF24 first sets up SPI, so the CC1101 then works (Bruce issue #1909). A board with buffered/isolated SPI (e.g. the RF Pack S3's SN74) avoids the ordering problem entirely.
My module says not found right after I bought it — is it defective?
Almost certainly not. Confirm you flashed Bruce, set the right pin map, and that the cap matches your exact device model (ADV vs v1.1). Hardware failure is the last thing to suspect.
Does a 433 MHz module work on 868/915 MHz?
The CC1101 chip covers those bands, but a 433-tuned board and antenna perform poorly elsewhere. Use a band-matched module and antenna.

Want a board that's Bruce-ready out of the box?

Each PINGEQUA M5Stack RF module ships with the pin map and menu path documented, so "not found" doesn't cost you an evening.

RF Pack S3 (StickS3) → Cardputer ADV — Hydra RF → Cardputer v1.1 — 3-in-1 →

Sources & further reading: Bruce firmware — BruceDevices/firmware, releases; CC1101 setup — Bruce wiki; "not found" reports — #2035, #1909, #2148. Versions verified June 2026 — check the releases page for the latest.

For authorized security testing and education only. Use RF hardware only on devices and frequencies you are permitted to operate. You are responsible for compliance with all applicable laws and radio regulations (e.g. FCC Part 15 in the US, CE/RED in the EU). "M5Stack", "Bruce" and "Flipper Zero" are referenced for compatibility; PINGEQUA is independent and not affiliated with or endorsed by their owners.

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