README.md

ArduinoNRF documentation

All project documentation lives here. Start with the project README for the overview and quick start.

Getting started & status

• COMPATIBILITY.md — OS support matrix (Windows / Linux / macOS) and real-board identity audit
• VALIDATION.md — what's verified on real hardware, timing, and how to reproduce it
• Release notes: the GitHub Releases page

Uploading

• uploads/hands_free_upload.md — button-less UF2 / serial-DFU on the maintenance CDC, UF2 drive-only mode, stale-port protection, and SWD-probe fallbacks
• platform/UPLOAD_BEHAVIOR.md — upload policy and behavior
• bootloaders/README.md — bootloader families

Debugging

• platform/ARDUINO_IDE2_USB_GDBSTUB.md — single-cable USB-CDC GDB-stub debugging in Arduino IDE 2
• examples/vscode/README.md — sample launch.json / tasks.json for VS Code + cortex-debug

Boards

• boards/README.md — per-board reference index
• platform/BOARD_SUPPORT_STATUS.md — support matrix
• platform/BOARD_SUPPORT_NOTES.md · platform/BOARD_FAMILY_MATRIX.md — family notes & matrix

Peripherals (subsystem drivers)

• platform/PWM_MULTI_MODULE.md — 4-module / 16-channel PWM facade, per-pin frequency, polarity, complementary pairs
• platform/RTC_DRIVER.md — low-level driver for RTC0/1/2 (compare + overflow IRQs)
• cores/arduino/NrfPower.h — power management: System ON sleep (WFI/WFE), low-power / constant-latency sub-modes, DCDC, RAM retention, SystemOFF + GPIO / NFC / USB wake sources
• cores/arduino/NrfNfcTag.h — NFC-A Type 2 tag emulation (NDEF URI / text), field detect IRQ, read count
• cores/arduino/NrfPeripherals.h — NrfRng (TRNG), NrfWdt (watchdog), NrfTemp (die temp), NrfQdec (rotary encoder), NrfTimer (TIMER0–4), NrfNvmc (flash erase/write), NrfPpi (peripheral routing), NrfEgu (software events + SWI on 6 channels), NrfComp (analog comparator), NrfMwu (memory watch unit), NrfGpioteOut (output channels for PPI use)
• cores/arduino/NrfMediaPeripherals.h — NrfQspi (external NOR flash), NrfPdm (MEMS mic), NrfI2s (digital audio). API complete; not verified on the reference ProMicro (no external flash/mic/codec wired) — boards with that hardware need their own verification pass.

Wireless stacks

• NimBLE (libraries/NimBLE/) — working. The vendored Apache Mynewt NimBLE host+controller runs on a bare-metal cooperative port. Advertising, connections, MTU exchange, and full GATT service/characteristic/descriptor discovery are verified on hardware against Windows (bleak/WinRT), Android (nRF Connect), and board-to-board. Exchange data over the built-in Nordic UART service with NimBLE::write() / NimBLE::onReceive(). See the BLE section of the project README and the NimBLESmoke, BLESend, and BLEReceive examples.
• Zigbee / 802.15.4. The future-facing onboard path is Nordic's official nCS Zigbee R23 add-on as a sidecar firmware flow for the nRF52840's own RADIO. The existing Arduino sketch path remains the external CC2530 module: flash it with the built-in CC-Debugger (libraries/CCDebugger/, no external programmer) and drive it with the separate ArduinoNRF-Zigbee library. Full guide: platform/ZIGBEE.md.
• Thread (OpenThread) — working IPv6 mesh on the nRF52840's own radio. Full OpenThread FTD on a bare-metal 802.15.4 driver, in the separate NiusThread library (the in-package libraries/Thread/ is a compatibility shim). HW-verified two-node mesh with UDP. Full guide: platform/THREAD.md.
• CC310 (CryptoCell 310) — working hardware crypto on the nRF52840. SHA-256, AES-CBC/CTR, ECDSA/ECDH P-256, TRNG on the accelerator (CRYS runtime) plus AES-GCM (Oberon), in the separate NiusCrypto library (the in-package libraries/CC310/ is a compatibility shim). HW-verified on ProMicro. Nordic binaries are fetched locally — see NiusCrypto's docs/VENDORING.md.
• Not yet an Arduino sketch library: libraries/Zigbee/ remains an experimental placeholder and returns ZIGBEE_NOT_VENDORED. Official onboard Zigbee starts with the nCS sidecar tools in tools/ncs_zigbee.

Platform reference (capabilities & truth)

• platform/HARDWARE_CAPABILITIES.md — what the core exposes
• platform/PWM_BEHAVIOR.md · platform/PWM_TIMER_BOUNDARIES.md — PWM model & frequency/resolution limits (multi-module summary; full model in platform/PWM_MULTI_MODULE.md)
• platform/POWER_ADC_NOTES.md — ADC / battery-sense behavior
• platform/BLE_WIFI_BOUNDARIES.md — BLE/WiFi facade boundaries (BLE is now a full NimBLE stack; WiFi remains out of scope on nRF52)
• platform/OFFICIAL_STACKS.md - Nordic official stack policy and version pinning
• platform/RADIO_POLICY.md - onboard RADIO ownership rules
• platform/THREAD.md — Thread (OpenThread) mesh on the native radio via the NiusThread library
• platform/ZIGBEE.md - official nCS Zigbee R23 sidecar plus the external CC2530 path
• platform/REFERENCE_COMPARISON.md — comparison vs pdcook/nRFMicro-Arduino-Core