Easy reprogramming, comes pre-loaded with the UF2 bootloader, which looks like a USB storage key.When used in Circuit Python, the 2 MB flash acts as storage for all your scripts, libraries and files. You can use the SPI Flash storage like a very tiny hard drive. 2 MB QSPI Flash storage chip is included on board.Next to the reset button there is an RGB NeoPixel that can be used for any purpose. One green power LED, two RX/TX LEDs for data being sent over USB, and a red LED connected.

Four indicator LEDs and one NeoPixel, on the front edge of the PCB, for easy debugging.It can also act like an HID keyboard or mouse. When used to act like a serial device, the USB interface can be used by any computer to listen/send data to the METRO, and can also be used to launch and update code via the bootloader. Native USB, there’s no need for a hardware USB to Serial converter as the Metro M4 has built in USB support.There’s a hardware SPI port, hardware I2C port and hardware UART. METRO has 25 GPIO pins, 8 of which are analog in, and two of which is a true analog out.The METRO will automagically switch between USB and DC. The 2.1 mm DC jack has an on/off switch next to it so you can turn off your setup easily.

Power the METRO M4 with 7-9 V polarity protected DC or the micro USB connector to any 5 V USB source.

Floating point support with Cortex M4 DSP instructions.

It’s got analog pins where you expect, and SPI/UART/I2C hardware support in the same spot as the Metro 328 and M0. This Metro is the same size as the others, and is compatible with many shields. To start off the ATSAMD51 journey it has a classic ‘Arduino compatible’ shape and pinout. Your code will zig and zag and zoom, and with a bunch of extra peripherals for support, this will for sure be your favorite new chipset. This Metro is like a bullet train, with it’s 120 MHz Cortex M4 with floating point support. The most powerful Metro at this time, the Adafruit Metro M4 featuring the Microchip ATSAMD51.

Metro 4 download