ATSAMD21G18 ARM Cortex M0 processor, clocked at 48 MHz and at 3.3V logic, the same one used in the new Arduino Zero. This chip has a whopping 256K of FLASH (8x more than the Atmega328) and 32K of RAM (16x as much)!
This chip comes with built in USB so it has USB-to-Serial program & debug capability built in with no need for an FTDI-like chip.
Power the METRO with 7-9V polarity protected DC or the micro USB connector to any 5V USB source. The 2.1mm DC jack has an on/off switch next to it so you can turn off your setup easily. The METRO will automagically switch between USB and DC.
METRO has 25 GPIO pins, 12 of which are analog in, and one of which is a true analog out. There's a hardware SPI port, hardware I2C port and hardware UART. Logic level is 3.3V
Easy reprogramming, comes pre-loaded with the UF2 bootloader, which looks like a USB storage key. Simply drag firmware on to program, no special tools or drivers needed! It can be used to load up CircuitPython, PXT MakeCode or Arduino IDE (it is bossa-compatible)

Technical Details

Product Details

Product Dimensions

Package Dimensions
Width : 2 inch
Height : 1 inch
Length : 3 inch

Item Weight: 3.04 ounce (View shipping rates and policies)
Shipping Weight: 3.04 ounce (View shipping rates and policies)

ASIN : B071P145RG