Adafruit Feather 32u4 FONA

Feather is the new development board from Adafruit, designed to be thin, light, and portable. The Adafruit Feather 32u4 FONA combines an Arduino-compatible microcontroller with an audio, SMS, and data-capable cellular module, built-in USB and battery charging.

At its core, it features an ATmega32u4 clocked at 8 MHz with 3.3V logic, 32K of flash, 2K of RAM, and built-in USB for programming and debugging without the need for additional chips. It supports USB device functions like mouse, keyboard, and MIDI.

This board includes a connector for any 3.7V Lithium polymer battery (minimum 500mAh recommended for operation) with built-in battery charging through microUSB at 500mA.

Dimensions and specs:

• Measures 2.4" x 0.9" x 0.28" (61mm x 23mm x 7mm)
• Weight: 8.2 grams
• ATmega32u4 @ 8MHz with 3.3V logic
• 3.3V regulator with 500mA peak output
• USB bootloader and serial debugging
• 20 GPIO pins, 7 PWM pins, 10 analog inputs
• Hardware Serial, I2C, and SPI support
• 500mA Lipoly charger with status LED
• Pin #13 red LED
• Power enable pin for 3.3V regulator
• 4 mounting holes and reset button

The cellular module is the SIM800 quad-band GSM module capable of:

• Global GSM 2G network coverage (850/900/1800/1900MHz)
• Voice calls with external speaker and microphone support
• SMS messaging
• GPRS data (TCP/IP, HTTP)
• FM radio broadcast reception
• AT command interface with auto-baud detection
• Bluetooth client interface with SPP and audio

Required accessories (not included):

• 2G Mini SIM card (T-Mobile or resellers recommended in USA)
• 500mAh or larger Lipoly battery
• MicroUSB cable for charging
• External antenna (slim sticker-type preferred) and necessary adapters
• External electret microphone and 8 Ohm speaker for calls

See the tutorial for schematics, usage instructions, and more.