# Arduino Mega 2560 R3 > High-pin-count Arduino board based on the ATmega2560 at 16 MHz with 256KB flash, 54 digital I/O pins, 16 analog inputs, and 4 hardware UARTs for complex projects. ## Quick Facts - **Brand:** Arduino - **Board Type:** dev-board - **Price:** ~$47.8 - **Product Readiness:** developer - **CPU:** ATmega2560 @ 16 MHz - **CPU Architecture:** AVR - **CPU Cores:** 1 - **RAM:** 8 KB - **Flash:** 256 KB - **Power:** 5V via USB or 7-12V DC barrel jack - **Operating Voltage:** 5V - **Dimensions:** 101.52 × 53.3 mm - **Weight:** 37g - **SD Card:** No ## Open Source - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes ## Compatible Firmware arduino, platformio ## Use Cases - prototyping - robotics - automation - education ## Components - **ATmega2560** (mcu): 8-bit AVR RISC microcontroller at 16 MHz with 256KB flash, 8KB SRAM, 4KB EEPROM, 54 digital I/O, 16 analog inputs — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-shop.adafruit.com%2Fproduct-files%2F191%2FATmega640-1280-1281-2560-2561-Datasheet-DS40002211A.pdf&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) ## Protocols - **UART**: TX0: D1, RX0: D0, TX1: D18, RX1: D19, TX2: D16, RX2: D17, TX3: D14, RX3: D15 - **SPI**: MOSI: D51, MISO: D50, SCK: D52, SS: D53 - **I2C**: SDA: D20, SCL: D21 - **ICSP** ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | D0 | UART0 RX | UART | digital-input, digital-output | | D1 | UART0 TX | UART | digital-input, digital-output | | D2 | Digital I/O, PWM, External Interrupt | — | digital-input, digital-output, pwm, interrupt | | D3 | Digital I/O, PWM, External Interrupt | — | digital-input, digital-output, pwm, interrupt | | D4 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D5 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D6 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D7 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D8 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D9 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D10 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D11 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D12 | Digital I/O, PWM | — | digital-input, digital-output, pwm | | D13 | Digital I/O, PWM, Onboard LED | — | digital-input, digital-output, pwm | | D14 | UART3 TX | UART | digital-input, digital-output | | D15 | UART3 RX | UART | digital-input, digital-output | | D16 | UART2 TX | UART | digital-input, digital-output | | D17 | UART2 RX | UART | digital-input, digital-output | | D18 | UART1 TX, External Interrupt 3 | UART | digital-input, digital-output, interrupt | | D19 | UART1 RX, External Interrupt 2 | UART | digital-input, digital-output, interrupt | | D20 | I2C SDA, External Interrupt 1 | I2C | digital-input, digital-output, interrupt | | D21 | I2C SCL, External Interrupt 0 | I2C | digital-input, digital-output, interrupt | | D50 | SPI MISO | SPI | digital-input, digital-output | | D51 | SPI MOSI | SPI | digital-input, digital-output | | D52 | SPI SCK | SPI | digital-input, digital-output | | D53 | SPI SS | SPI | digital-input, digital-output | | A0 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A1 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A2 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A3 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A4 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A5 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A6 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A7 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A8 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A9 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A10 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A11 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A12 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A13 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A14 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | | A15 | Analog Input / Digital I/O | — | analog-input, digital-input, digital-output | ## Available Software - **[Arduino IDE]()** (open-source) - **[PlatformIO]()** (open-source) ## Description ## Overview The Arduino Mega 2560 R3 is a microcontroller development board based on the ATmega2560 running at 16 MHz. With 54 digital I/O pins (15 PWM-capable), 16 analog inputs, and four hardware UARTs, it is the go-to Arduino board for projects that outgrow the UNO's pin count. The R3 revision brought compatibility improvements aligned with the Arduino R3 standard. The board provides 256KB of flash memory (8KB reserved for the bootloader), 8KB of SRAM, and 4KB of EEPROM — significantly more than the UNO-class boards. This makes it well suited for projects requiring large lookup tables, complex state machines, or data buffering. Power can be supplied via USB or through the onboard DC barrel jack accepting 7–12V. The 16 MHz crystal oscillator and USB connectivity via an ATmega16U2 USB-to-serial bridge (R3 revision) ensure reliable programming and communication through the standard Arduino IDE. The Arduino Mega 2560 R3 is officially released under open hardware licenses with schematics and design files publicly available, making it widely supported by shields, libraries, and third-party accessories. ## Where to Buy - [Arduino Store (US)](https://openhardware.directory/r?to=https%3A%2F%2Fstore-usa.arduino.cc%2Fproducts%2Farduino-mega-2560-rev3&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $47.80 - [Arduino Store (EU)](https://openhardware.directory/r?to=https%3A%2F%2Fstore.arduino.cc%2Fproducts%2Farduino-mega-2560-rev3&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — €52.80 - [DigiKey](https://openhardware.directory/r?to=https%3A%2F%2Fwww.digikey.com%2Fen%2Fproducts%2Fdetail%2Farduino%2FA000067%2F3476357&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $48.40 - [Mouser](https://openhardware.directory/r?to=https%3A%2F%2Fwww.mouser.com%2FProductDetail%2FArduino%2FA000067&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $48.40 - [Amazon US](https://openhardware.directory/r?to=https%3A%2F%2Fwww.amazon.com%2Fdp%2FB0046AMGW0&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $48.40 - [SparkFun](https://openhardware.directory/r?to=https%3A%2F%2Fwww.sparkfun.com%2Farduino-mega-2560-r3.html&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $48.40 - [Adafruit](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F191&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) — $48.50 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F191&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) - [datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-shop.adafruit.com%2Fproduct-files%2F191%2FATmega640-1280-1281-2560-2561-Datasheet-DS40002211A.pdf&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) - [wiki](https://openhardware.directory/r?to=https%3A%2F%2Fdocs.arduino.cc%2Fhardware%2Fmega-2560&ref=openhardware.directory&product=arduino-mega-2560-r3&source=md-export) ## Tags `arduino`, `atmega2560`, `avr`, `microcontroller`, `development-board`, `high-pin-count` ## Images ![Arduino Mega 2560 R3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/arduino-mega-2560-r3/1c2cb9565476.jpg) ![Arduino Mega 2560 R3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/arduino-mega-2560-r3/08a53736f135.jpg) --- [View full device page](https://openhardware.directory/devices/arduino-mega-2560-r3)