# Adafruit Feather 32u4 RFM69HCW 868/915 MHz > ATmega32u4 Feather board with RFM69HCW sub-GHz radio supporting 868/915 MHz with up to +20 dBm transmit power, AES-128 encryption, and 100mA LiPo charger for long-range IoT sensor networks. ## Quick Facts - **Brand:** Adafruit - **Board Type:** dev-board - **Price:** ~$24.95 - **Product Readiness:** developer - **CPU:** ATmega32u4 @ 8 MHz - **CPU Architecture:** AVR 8-bit - **CPU Cores:** 1 - **RAM:** 2.5KB SRAM - **Flash:** 32KB - **Power:** 5V + LiPo - **Operating Voltage:** 3.3V - **Dimensions:** 51 × 23 × 8 mm - **Weight:** 5.5g - **Antenna:** U.FL/IPEX ## Connectivity - **Lora:** RFM69HCW 868/915MHz SX1231 (FSK/OOK, not LoRa) ## Open Source - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes ## Compatible Firmware arduino ## Use Cases - iot - long-range-sensor-network - remote-sensor-nodes - sub-ghz-communication - prototyping ## Components - **ATmega32u4** (mcu): 8-bit AVR microcontroller at 8MHz, 3.3V, native USB, 32KB flash, 2.5KB SRAM. — [Datasheet](https://openhardware.directory/r?to=http%3A%2F%2Fwww.atmel.com%2FImages%2FAtmel-7766-8-bit-AVR-ATmega16U4-32U4_Datasheet.pdf&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) - **RFM69HCW** (sub-ghz-radio): HopeRF RFM69HCW 868/915MHz radio module based on SX1231, +13 to +20 dBm TX, AES-128, FSK/OOK modulation. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-shop.adafruit.com%2Fproduct-files%2F3076%2FRFM69HCW-V1.1.pdf&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) ## Protocols - **SPI**: MOSI: D16, MISO: D14, SCK: D15 - **I2C**: SDA: D2, SCL: D3 - **UART**: TX: D1, RX: D0 - **RFM69 packet radio**: ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | D0 | RX — UART Receive | UART | digital-input, digital-output | | D1 | TX — UART Transmit | UART | digital-input, digital-output | | D5 | D5 — GPIO / PWM | — | digital-input, digital-output, pwm | | D6 | D6 — GPIO / PWM | — | digital-input, digital-output, pwm | | D9 | D9 — GPIO / PWM / Analog | — | digital-input, digital-output, pwm, analog-input | | D10 | D10 — GPIO / PWM | — | digital-input, digital-output, pwm | | D16 | D11/MOSI — SPI MOSI | SPI | digital-input, digital-output | | D14 | D12/MISO — SPI MISO | SPI | digital-input, digital-output | | D15 | D13/SCK — SPI Clock / LED | SPI | digital-input, digital-output | | D2 | SDA — I2C Data | I2C | digital-input, digital-output | | D3 | SCL — I2C Clock | I2C | digital-input, digital-output | | D15 | A0 — Analog In | — | analog-input | | D4 | A1 — Analog In | — | analog-input | | D5 | A2 — Analog In | — | analog-input | | D12 | A3 — Analog In | — | analog-input | | D24 | A4/SDA — Analog In / I2C SDA | I2C | analog-input, digital-input, digital-output | | D25 | A5/SCL — Analog In / I2C SCL | I2C | analog-input, digital-input, digital-output | ## Description ## Overview The Adafruit Feather 32u4 RFM69HCW (868/915 MHz) combines the ATmega32u4 microcontroller with HopeRF's RFM69HCW radio module — a versatile sub-GHz transceiver based on the Semtech SX1231. The radio operates in the 868 MHz (Europe) or 915 MHz (Americas) ISM bands and can transmit at up to +20 dBm (100mW), achieving a range of approximately 350 meters in open space. The RFM69HCW supports AES-128 hardware encryption and is ideal for building private wireless sensor networks without a LoRaWAN gateway. It uses a simple packet-based protocol that Adafruit's RadioHead library makes easy to work with, supporting addressed packets, automatic acknowledgment, and mesh-style routing. Power management follows the Feather standard: a JST connector accepts a 3.7V LiPo battery, and a built-in 100mA charger keeps it topped up via the Micro-USB port. The 3.3V regulator provides 500mA for peripherals. An onboard u.FL connector allows attaching an external antenna for extended range beyond the included wire stub. With 20 GPIO pins, 10 analog inputs, 7 PWM outputs, and hardware Serial/I2C/SPI, this board is a capable platform for remote sensor nodes, weather stations, and any point-to-point or small mesh network needing reliable sub-GHz communication. ## Where to Buy - [Adafruit](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F3076&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) — 24.95 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F3076&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fadafruit%2FAdafruit-Feather-32u4-RFM-LoRa-PCB&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) - [wiki](https://openhardware.directory/r?to=https%3A%2F%2Flearn.adafruit.com%2Fadafruit-feather-32u4-radio-with-rfm69hcw-module%2Foverview&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) - [datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-shop.adafruit.com%2Fproduct-files%2F3076%2FRFM69HCW-V1.1.pdf&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) - [schematics](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-learn.adafruit.com%2Fassets%2Fassets%2F000%2F031%2F603%2Fmedium800%2Ffeather_schem.png&ref=openhardware.directory&product=adafruit-feather-32u4-rfm69hcw-868-915&source=md-export) ## Tags `feather`, `rfm69`, `sub-ghz`, `868mhz`, `915mhz`, `atmega32u4`, `iot`, `sensor-network`, `adafruit` ## Images ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/50cdedf15845.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/82a65e79c297.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/dc0682aaf0f4.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/4fa1154ebdc0.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/72850515fa8d.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/374ab482484b.jpg) ![Adafruit Feather 32u4 RFM69HCW 868/915 MHz](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-feather-32u4-rfm69hcw-868-915/74f602e12906.jpg) --- [View full device page](https://openhardware.directory/devices/adafruit-feather-32u4-rfm69hcw-868-915)