Adafruit Feather 32u4 RFM69HCW (868/915 MHz) - image 1
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Adafruit·Dev Board

Adafruit Feather 32u4 RFM69HCW (868/915 MHz)

Feather-format development board combining the ATmega32u4 microcontroller with an RFM69HCW 868/915 MHz packet radio for low-power sub-GHz wireless applications.

Starting from

$24.95

Compatible Firmware

Specifications

ArchitectureAVR
CPU Cores1
Clock Speed8MHz
Flash32KB
GPIO Level3.3V
AntennaU.FL/IPEX
Storagenone
Dimensions51.0 × 22.8 × 8mm
Weight5g

Components

8-bit AVR microcontroller with native USB, 32KB flash, 2KB SRAM, running at 8MHz on 3.3V

HopeRF RFM69HCW sub-GHz packet radio transceiver operating at 868/915 MHz with up to +20 dBm output and AES-128 encryption

Microchip MCP73831 single-cell LiPo/LiIon battery charger IC providing up to 100mA charge current via USB

Bus Interfaces

I2C
SCL: D3SDA: D2
SPI
CS: D10SCK: D15MISO: D14MOSI: D16
UART
RX: D0TX: D1

GPIO Map

D0
RX — UART Receive
digital-inputdigital-output
UART
D1
TX — UART Transmit
digital-inputdigital-output
UART
D2
SDA — I2C Data
digital-inputdigital-output
I2C
D3
SCL — I2C Clock
digital-inputdigital-outputpwm
I2C
D4
Radio RST
digital-inputdigital-output
GPIO
D5
GPIO / PWM
digital-inputdigital-outputpwm
GPIO
D6
GPIO / PWM
digital-inputdigital-outputpwm
GPIO
D7
Radio IRQ
digital-input
GPIO
D8
Radio CS
digital-inputdigital-output
SPI
D9
GPIO / PWM
digital-inputdigital-outputpwm
GPIO
D10
SPI CS / PWM
digital-inputdigital-outputpwm
SPI
D11
GPIO / PWM
digital-inputdigital-outputpwm
GPIO
D13
LED / PWM
digital-inputdigital-outputpwm
GPIO
D14
MISO — SPI
digital-inputdigital-output
SPI
D15
SCK — SPI Clock
digital-inputdigital-output
SPI
D16
MOSI — SPI
digital-inputdigital-output
SPI
A0
Analog Input 0 (D18)
digital-inputdigital-outputanalog-input
GPIO
A1
Analog Input 1 (D19)
digital-inputdigital-outputanalog-input
GPIO
A2
Analog Input 2 (D20)
digital-inputdigital-outputanalog-input
GPIO
A3
Analog Input 3 (D21)
digital-inputdigital-outputanalog-input
GPIO
A4
Analog Input 4 (D22)
digital-inputdigital-outputanalog-input
GPIO
A5
Analog Input 5 (D23)
digital-inputdigital-outputanalog-input
GPIO

Overview

The Adafruit Feather 32u4 RFM69HCW is a compact, all-in-one development board that pairs the popular ATmega32u4 microcontroller with an HopeRF RFM69HCW 868/915 MHz packet radio transceiver. Built on Adafruit's Feather form factor, it brings long-range sub-GHz wireless communication to a tiny, breadboard-friendly package, making it ideal for sensor nodes, wireless telemetry, and mesh network deployments where low power consumption is critical.

The ATmega32u4 is an 8-bit AVR microcontroller running at 8 MHz with 32KB of flash and 2KB of SRAM. It features native USB support, eliminating the need for a separate USB-to-serial chip and enabling USB HID, CDC, and MIDI device emulation out of the box. The 3.3V operating voltage ensures compatibility with modern sensors and radio modules without level shifting.

The RFM69HCW radio module operates in the 868 MHz (Europe) and 915 MHz (North America) ISM bands, delivering up to +20 dBm output power and a receiver sensitivity of –120 dBm. It supports packet-based communication with built-in AES-128 encryption, CRC error checking, and RSSI measurement, making it well suited for point-to-point links, star topologies, and mesh networks using libraries such as RadioHead or the Adafruit fork of LowPowerLab's RFM69 library.

Conforming to the Feather specification, the board measures 51.0 × 22.8 × 8 mm and includes a built-in 100 mA LiPo charger (MCP73831), a JST PH connector for a 3.7 V LiPo battery, and Micro-USB for programming and charging. Mounting holes and a U.FL/IPEX antenna connector complete the hardware. The board is fully supported by the Arduino IDE and PlatformIO, and Adafruit publishes open-source schematics and PCB layout files.

Use Cases

4

Resources

Where to Buy

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