Adafruit Metro M4 feat. Microchip ATSAMD51

Micro USB
Micro USB port powers the Metro M4 with 5V at about 500mA and provides the USB data/programming connection; Adafruit notes the USB input has a fuse that trips temporarily above about 1000mA.
Type · power usb dataVoltage · 5V USB input; draw up to about 500mA combined between Vin, 5V and 3.3V supplies when USB-powered.
DC jack
5.5mm/2.1mm centre-positive DC jack for external board power; Adafruit states this is one of the two primary power inputs.
Type · power inputVoltage · 6V-12V input recommended on the DC jack; up to about 800mA between 5V and 3.3V supplies, and 2A from Vin, per Adafruit.
3V
Output from the onboard 3.3V regulator for peripherals and logic reference.
Type · power outputVoltage · 3.3V output, 500mA peak per Adafruit; board logic is 3.3V.
5V
Output from the 5V regulator when DC jack powered, or from USB when USB powered.
Type · power outputVoltage · 5V output, about 500mA peak from USB or about 800mA peak from DC jack per Adafruit.
GND

Start wiring

USB · 3.3 V

Confirm the data interface matches your host board.

Module pins: 5V, Vin, GND. Schematik maps them to your board in the app.

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Position

Type

Function

Voltage

Micro USB

power usb data

Micro USB port powers the Metro M4 with 5V at about 500mA and provides the USB data/programming connection; Adafruit notes the USB input has a fuse that trips temporarily above about 1000mA.

5V USB input; draw up to about 500mA combined between Vin, 5V and 3.3V supplies when USB-powered.

DC jack

power input

5.5mm/2.1mm centre-positive DC jack for external board power; Adafruit states this is one of the two primary power inputs.

6V-12V input recommended on the DC jack; up to about 800mA between 5V and 3.3V supplies, and 2A from Vin, per Adafruit.

power output

Output from the onboard 3.3V regulator for peripherals and logic reference.

3.3V output, 500mA peak per Adafruit; board logic is 3.3V.

power output

Output from the 5V regulator when DC jack powered, or from USB when USB powered.

5V output, about 500mA peak from USB or about 800mA peak from DC jack per Adafruit.

GND

ground

Common ground for all power and logic connections.

0V reference.

Vin

power input output

Higher of the DC jack or USB voltage; can be used as the raw input/output rail described by Adafruit.

Vin is the DC jack voltage when DC is connected, e.g. 9V, or 5V when only USB is connected.

#0 / RX

digital uart

GPIO #0 and Serial1 hardware UART receive input.

3.3V logic.

#1 / TX

digital uart

GPIO #1 and Serial1 hardware UART transmit output; also used as I2S SDI on this board according to Adafruit's I2S mapping.

3.3V logic.

#2-#12

digital gpio

General-purpose digital GPIO pins; Adafruit notes all pins except SCL can do PWM output, with pins also usable as interrupt inputs.

3.3V logic.

#13 / L

digital gpio led

GPIO #13, PWM-capable, connected to the red LED marked L next to the USB jack.

3.3V logic.

SDA / A6

i2c analog

I2C Wire data pin; also available as analogue input A6. Adafruit notes no pull-up is fitted by default.

3.3V logic; external I2C pull-up of about 2.2K-10K may be needed.

SCL / A7

i2c analog

I2C Wire clock pin; also available as analogue input A7. Adafruit notes no pull-up is fitted by default.

3.3V logic; external I2C pull-up of about 2.2K-10K may be needed.

analog dac gpio

Analogue input A0 and true analogue output DAC channel; also digital I/O.

0V to 3.3V analogue output range per Adafruit.

analog dac gpio

Analogue input A1 and true analogue output DAC channel; also digital I/O.

0V to 3.3V analogue output range per Adafruit.

A2-A5

analog gpio

Analogue input pins that are also usable as digital I/O pins.

3.3V logic / analogue input range scoped by board logic.

SCK / MOSI / MISO

spi gpio

Hardware SPI pins connected to the 2x3 header; Adafruit says they can also be used as everyday GPIO but are best kept free for high-speed hardware SPI.

3.3V logic.

I2S pins

i2s audio

Fixed I2S peripheral mapping: pin 8 SDO/data out, pin 1 SDI/data in, pin 3 bit clock, pin 9 word select, and pin 2 master clock.

3.3V logic.

SWD header

debug

2x5 0.05 inch pitch SWD debug/programming interface exposed on the board.

3.3V debug interface implied by ATSAMD51 board logic.

Pinout

Start wiring

Arduino

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Add-ons

Pi Pico