Adafruit METRO 328 without Headers
ATmega328-based Arduino-compatible board with GPIO, analog inputs, hardware UART, SPI, I2C, timers, and PWM. Includes USB-serial converter. Ships without headers.
Pinout
- VIN / DC jack input
External DC input for powering the METRO; Adafruit states 7-9V polarity-protected DC or 5V from micro USB.
Type · powerVoltage · 7-9V DC on external input, or 5V from micro USB per Adafruit product page - 5V
5V board rail; product page states 5V logic and a 5V regulator with peak current limits.
Type · powerVoltage · 5V - 3.3V
3.3V regulator output; product page states a 3.3V regulator with peak current limits and optional 3.3V logic conversion by jumper.
Type · powerVoltage · 3.3V - GND
Board ground rail for shields, headers, USB, and external circuits.
Type · groundVoltage · 0V - Digital I/O D0-D13
ATmega328P digital GPIO header group; Adafruit states the METRO has 20 GPIO pins and is Arduino UNO R3 shield/pin compatible.
Start wiring
USB · 3.3 V
Confirm the data interface matches your host board.
Module pins: VIN / DC jack input, 5V, 3.3V, GND, Digital I/O D0-D13, PWM outputs, Analog inputs A0-A5. Schematik maps them to your board in the app.
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