We sure love the ATmega328 here at Adafruit, and we use them a lot for our own projects. The processor has plenty of GPIO, Analog inputs, hardware UART SPI and I2C, timers and PWM galore - just enough for most simple projects. When we need to go small, we use a Metro Mini or a Trinket M0, but when size isn't as much of a concern, we reach for an Adafruit METRO.
New! We've updated this product to our Adafruit Metro 328, a fully assembled Arduino-compatible. If using with the Arduino IDE, select "Arduino UNO" in the board selection drop down.
This is the Adafruit METRO with headers. It comes with headers soldered on. It's a fully assembled and tested board with through-hole headers attached. If you don't want a Metro with the headers attached for super-slimness, check out our Metro without Headers.
METRO is the culmination of years of playing with AVRs: we wanted to make a development board that is easy to use and is hacker friendly. At the heart is an ATmega328P, with 32KB of flash and 2KB of RAM, running at 16 MHz. It comes with the Optiboot bootloader already installed, and is Arduino IDE compatible.
We also include 4 rubber bumpers to keep it from slipping off your desk. Metro shown with our 12x capacitive touch shield attached just to demonstrate the headers, but that shield is not included!
- ATmega328 microcontroller with Optiboot (UNO) Bootloader
- USB Programming and debugging via the well-supported genuine CP2104
- Input voltage: 7-9V (a 9VDC power supply is recommended)
- 5V regulator can supply peak ~800mA as long as the die temp of the regulator does not exceed 150*C
- 3.3V regulator can supply peak ~150mA as long as the die temp of the regulator does not exceed 150*C
- 5V logic with 3.3V compatible inputs, can be converted to 3.3V logic operation
- 20 Digital I/O Pins: 6 are also PWM outputs and 6 are also Analog Inputs
- 6-pin ICSP Header for reprogramming
- 32KB Flash Memory - 0.5K for bootloader, 31.5KB available after bootloading
- 16MHz Clock Speed
- Compatible with "Classic" and "R3" Shields
- Adafruit Black PCB with gold plate on pads
- 53mm x 71mm / 2.1" x 2.8"
- Height (w/ barrel jack): 13mm / 0.5"
- Weight: 19g
- Derivative of "Arduino UNO R3 Reference design"
- Open source hardware files on github!
- As of March 30, 2018 we now have changed this item to be an Arduino-compatible Adafruit Metro 328 with SiLabs CP2104 USB serial chip
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