
ATmega2560-based board with 54 digital I/O pins (15 PWM), 16 analog inputs, 4 hardware UARTs, 16 MHz, and USB-B. A large I/O count makes it suitable for projects that exhaust Uno pins. Discontinued — the Adafruit Grand Central M4 is a current alternative.

Pins 1–40
Pins 41–80
Pins 81–82
4 grouped source records are expanded into separate logical pads where unambiguous; physical placement is not implied.
External input supply rail for the Arduino Mega 2560 board, from the official Arduino Mega 2560 documentation/pinout.
Regulated 5V board rail exposed on the Mega 2560 headers.
3.3V board rail exposed on the Mega 2560 headers.
Ground reference pins exposed on the Mega 2560 headers.
Reset input exposed on the board headers.
Digital I/O header pins for the Arduino Mega 2560 board; the official pinout groups these pins and marks their alternate functions.
Analogue input header pins for the Arduino Mega 2560 board.
I2C/TWI interface pins exposed on the Mega 2560 headers.
SPI signals exposed via the ICSP header and alternate digital pins on the Mega 2560.
Hardware serial UART transmit/receive pairs exposed on the Mega 2560 headers.
Analogue reference pin exposed on the board header.
| Pin | Type | Function | Voltage |
|---|---|---|---|
| VIN | Power | External input supply rail for the Arduino Mega 2560 board, from the official Arduino Mega 2560 documentation/pinout. | board external input rail, see official Arduino Mega 2560 documentation |
| 5V | Power | Regulated 5V board rail exposed on the Mega 2560 headers. | 5V |
| 3V3 | Power | 3.3V board rail exposed on the Mega 2560 headers. | 3.3V |
| GND | Ground | Ground reference pins exposed on the Mega 2560 headers. | 0V |
| RESET | Control | Reset input exposed on the board headers. | |
| D0-D53 | GPIO | Digital I/O header pins for the Arduino Mega 2560 board; the official pinout groups these pins and marks their alternate functions. | 5V logic board family |
| A0-A15 | Analog | Analogue input header pins for the Arduino Mega 2560 board. | analogue input range follows board reference, see Arduino documentation |
| SDASCL | I2C | I2C/TWI interface pins exposed on the Mega 2560 headers. | 5V logic board family |
| MOSIMISOSCK | SPI | SPI signals exposed via the ICSP header and alternate digital pins on the Mega 2560. | 5V logic board family |
| TX0RX0, TX1RX1, TX2RX2, TX3RX3 | UART | Hardware serial UART transmit/receive pairs exposed on the Mega 2560 headers. | 5V logic board family |
| AREF | Analog | Analogue reference pin exposed on the board header. |
Logical bank 1
Logical bank 2
Logical bank 3
4 grouped source records are expanded into separate logical pads where unambiguous; physical placement is not implied.
External input supply rail for the Arduino Mega 2560 board, from the official Arduino Mega 2560 documentation/pinout.
Regulated 5V board rail exposed on the Mega 2560 headers.
3.3V board rail exposed on the Mega 2560 headers.
Ground reference pins exposed on the Mega 2560 headers.
Reset input exposed on the board headers.
Digital I/O header pins for the Arduino Mega 2560 board; the official pinout groups these pins and marks their alternate functions.
Analogue input header pins for the Arduino Mega 2560 board.
I2C/TWI interface pins exposed on the Mega 2560 headers.
SPI signals exposed via the ICSP header and alternate digital pins on the Mega 2560.
Hardware serial UART transmit/receive pairs exposed on the Mega 2560 headers.
Analogue reference pin exposed on the board header.
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