# Adafruit Feather nRF52840 Express > Feather board with nRF52840 ARM Cortex-M4F at 64MHz, BLE 5.0, native USB (CDC/HID/MIDI/MSC), 1MB flash, 256KB SRAM, 2MB QSPI flash, 21 GPIO, SWD debug, and LiPo charging. Supports Arduino and CircuitPython. ## Quick Facts - **Brand:** Adafruit - **Board Type:** dev-board - **Price:** ~$24.95 - **Product Readiness:** consumer - **CPU:** Nordic nRF52840 ARM Cortex-M4F - **CPU Architecture:** ARM Cortex-M4F - **CPU Cores:** 1 - **RAM:** 256 KB - **Flash:** 1 MB - **Power:** 5V via Micro USB or 3.7V LiPo via JST connector - **Operating Voltage:** 3.3V - **Dimensions:** 51mm × 23mm × 7.2mm - **Weight:** 6g - **Antenna:** Built-in PCB antenna ## Connectivity - **Bluetooth:** BLE 5.0 ## Open Source - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes ## Certifications FCC, IC, TELEC ## Compatible Firmware circuitpython, arduino ## Use Cases - ble-beacons - wearable - usb-hid - iot-sensor-platform - prototyping ## Components - **nRF52840** (mcu): ARM Cortex-M4F at 64 MHz with 1 MB flash, 256 KB SRAM, Bluetooth 5.0, native USB, up to +8 dBm. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Finfocenter.nordicsemi.com%2Fpdf%2FnRF52840_PS_v1.1.pdf&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) - **GD25Q16C** (flash): 2 MB QSPI NOR flash for CircuitPython code and storage. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.gigadevice.com%2Fdatasheet%2Fgd25q16c%2F&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) ## Protocols - **I2C**: SDA: GPIO25, SCL: GPIO26 - **SPI**: MOSI: GPIO15, MISO: GPIO14, SCK: GPIO12 - **UART**: TX: GPIO6, RX: GPIO8 - **USB** - **Bluetooth LE** - **I2S** ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | GPIO4 | A0 — DAC/ADC | ADC | analog-input, dac, digital-input, digital-output, pwm | | GPIO5 | A1 — ADC | ADC | analog-input, digital-input, digital-output, pwm | | GPIO30 | A2 — ADC | ADC | analog-input, digital-input, digital-output | | GPIO28 | A3 — ADC | ADC | analog-input, digital-input, digital-output | | GPIO2 | A4 — ADC | ADC | analog-input, digital-input, digital-output, pwm | | GPIO3 | A5 — ADC | ADC | analog-input, digital-input, digital-output, pwm | | GPIO27 | D5 — GPIO/PWM | — | digital-input, digital-output, pwm | | GPIO11 | D6 — GPIO | — | digital-input, digital-output, pwm | | GPIO7 | D9 — GPIO/PWM | — | digital-input, digital-output, pwm | | GPIO26 | D10 — GPIO/PWM | — | digital-input, digital-output, pwm | | GPIO15 | D11 — MOSI | SPI | digital-input, digital-output | | GPIO14 | D12 — MISO | SPI | digital-input, digital-output | | GPIO12 | D13 — SCK | SPI | digital-input, digital-output | | GPIO25 | SDA — I2C | I2C | digital-input, digital-output | | GPIO26 | SCL — I2C | I2C | digital-input, digital-output | | GPIO6 | TX — UART | UART | digital-input, digital-output | | GPIO8 | RX — UART | UART | digital-input, digital-output | ## Available Software - **[CircuitPython]()** (open-source) - **[Arduino]()** (open-source) ## Description ## Overview The Adafruit Feather nRF52840 Express is the flagship Bluetooth Feather board, built on the Nordic Semiconductor nRF52840 SoC — the most capable chip in the nRF52 family. Running at 64 MHz with an ARM Cortex-M4F core, hardware floating-point, 1 MB of flash, and 256 KB of SRAM, it provides substantially more resources than the earlier nRF52832-based Feathers, plus the addition of native USB. The native USB in the nRF52840 is a standout feature: unlike the nRF52832 which required a USB-Serial bridge chip, the nRF52840 supports USB CDC, HID, MIDI, and Mass Storage natively. This enables the Feather to appear as a USB drive for CircuitPython drag-and-drop coding, emulate a keyboard or mouse, or act as a MIDI instrument — all simultaneously. The UF2 bootloader makes firmware flashing as easy as copying a file. Bluetooth 5.0 LE provides extended range (up to 4x the range of BLE 4.2 via coded PHY), 2x higher throughput (2 Mbps PHY), and supports advertising extensions. The radio achieves up to +8 dBm transmit power. Twenty-one GPIO pins expose 6 twelve-bit ADC channels, up to 12 PWM outputs across three modules, hardware SPI, UART, I2C, and I2S. A 2MB QSPI flash stores CircuitPython code and assets. A SWD debug connector (2×5 0.05" pitch), USER switch, NeoPixel, red LED, 4 mounting holes, and JST LiPo connector with integrated charger complete the hardware. FCC, IC, and TELEC certified. Compatible with all Feather Wings. ## Where to Buy - [Adafruit](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F4062&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) — 24.95 ## Resources - [product page](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F4062&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F4062&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) - [documentation](https://openhardware.directory/r?to=https%3A%2F%2Flearn.adafruit.com%2Fintroducing-the-adafruit-nrf52840-feather&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fadafruit%2FAdafruit-nRF52840-Express-PCB&ref=openhardware.directory&product=adafruit-feather-nrf52840-express&source=md-export) ## Tags `ble`, `bluetooth-5`, `nrf52840`, `cortex-m4`, `feather`, `adafruit`, `usb-hid`, `circuitpython`, `arduino`, `swd` ## Images ![Adafruit Feather nRF52840 Express](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-nrf52840-express/a52fd7266905.jpg) ![Adafruit Feather nRF52840 Express](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-nrf52840-express/13ae6768f661.jpg) --- [View full device page](https://openhardware.directory/devices/adafruit-feather-nrf52840-express)